Areas 1, 2, 3, 4, 6, 7, 8, 14, 16, 18, 19, 22 Test Completion Options: Option 1: All: Fill & Download for Free

This is EXACTLY the same situation I found myself in before Level 2 last year. Here is a detailed breakdown of how I spent each of my days during that period in what I believe is the best way to pass on your first try. This is my advice for using Schweser or other review materials, in my opinion the CFA Readings are too obtuse and will take you way too long with only 60 days left.Just as a note: whenever I say “Readthrough”, I always wrote down every relevant formula as I went. Although most of the task was reading the actual sections, I'm not especially math savvy and this helped with my review at the end. Also, you will notice that most sections are read through quite quickly. While not ideal, it is the best option in this case.Day 1 — Readthrough 1/3 Ethics(Take your time here, Ethics is one of two key sections)Day 2 — Readthrough 1/3 EthicsDay 3 — Readthrough 1/3 EthicsDay 4 — Readthrough 1/2 AlternativesDay 5 — Readthrough 1/2 AlternativesDay 6 — Readthrough 1/2 EconomicsDay 7 — Readthrough 1/2 EconomicsDay 8 — Readthrough 1/4 Equity(This is our other key section, really focus here)Day 9 — Readthrough 1/4 EquityDay 10 — Readthrough 1/4 EquityDay 11 — Readthrough 1/4 EquityDay 12 — Readthrough 1/2 DerivativesDay 13 — Readthrough 1/2 DerivativesDay 14 — Readthrough 1/2 CorpFinDay 15 — Readthrough 1/2 CorpFinDay 16 — Readthrough 1/3 FRA(While not at the same level of importance as Ethics and Equity, FRA is a close second and is very important fr Level 2)Day 17 — Readthrough 1/3 FRADay 18 — Readthrough 1/3 FRADay 19 — Readthrough 1/2 Portfolio ManagementDay 20 — Readthrough 1/2 Portfolio ManagementDay 21 — Readthrough 1/2 QuantDay 22 — Readthrough 1/2 QuantDay 23 — Readthrough 1/3 Fixed IncomeDay 24 — Readthrough 1/3 Fixed IncomeDay 25 — Readthrough 1/3 Fixed IncomeFor all of the above section, I was working full time (fortunately I have no children) and would study from 6pm — 1130pm every night, depending on the section.Day 26 — Review all of your written formulas for 3 to 4 hours until some have worked their way into your head.Day 27 — Take 1/2 Schweser Practice Exam and Review AnswersDay 28 — Take 1/2 Schweser Practice Exam and Review AnswersDay 29 — Take 1/2 Schweser Practice Exam and Review AnswersDay 30 — Take this day to recharge and simply find out which areas you did worst in, ordering them from #1 — #10 with #1 being your worst sectionDay 31 — Practice Quizzes on Problem Area #1 and Review your FlawsDay 32 — Practice Quizzes on Problem Area #1 and Review your FlawsDay 33 — Practice Quizzes on Problem Area #1 and Review your FlawsDay 34 — Practice Quizzes on Problem Area #2 and Review your FlawsDay 35 — Practice Quizzes on Problem Area #2 and Review your FlawsDay 36 — Practice Quizzes on Problem Area #3 and Review your FlawsDay 37 — Practice Quizzes on Problem Area #3 and Review your FlawsDay 38 — Practice Quizzes on Problem Area #4 and Review your FlawsDay 39 — Practice Quizzes on Problem Area #5 and Review your FlawsDay 40 — Practice Quizzes on Problem Area #6 and Review your FlawsDay 41 — Practice Quizzes on Problem Area #7 and #8 and Review your FlawsDay 42 — Practice Quizzes on Problem Area #9 and #10 and Review your FlawsDay 43 — Take 1/2 Schweser Practice Exam and Review AnswersDay 44 — Take 1/2 Schweser Practice Exam and Review AnswersDay 45 — Reread Ethics FullyDay 46 — Take 1/2 Schweser Practice Exam and Review AnswersDay 47 — Take CFA Official Practice Exam Timed and Complete with a full review of your problem areas.Day 48 — Take this day to recharge and, again, find all of the areas you are still having trouble with and list the worst 5 from #1 to #5Day 49 — Quiz and Review Problem Area #1Day 50 — Quiz and Review Problem Area #2Day 51 — Quiz and Review Problem Area #3Day 52 — Quiz and Review Problem Area #4Day 53 — Quiz and Review Problem Area #5Day 54 — Reread all of your formulas again for 3 or 4 hours today, you should be familiar with them all at this point.Day 55 — Take 1/2 Schweser Practice Exam and Review AnswersDay 56 — Take 1/2 Schweser Practice Exam and Review AnswersDay 57 — Take CFA Official Practice Exam Timed and Complete with a full review of your problem areas.Day 58 — Light review of your choice, try to relax and enjoy your life. Spend some time with friends in between reviewsDay 59 — Same as aboveDay 60 — Test! Congrats, you have worked your butt off!

After reading other people answers here i thought i would try to write maximum questions for helping students and now i am writing for the same .Edit : Some people are questioning if the facts provided here are genuine or not and why would i do this to help others and increase competition. Firstly why would not someone want to help fellow students, just look at the comments!I gave my paper on 19 May 2017 ( 2nd slot ) . I tried to do all questions as fast as possible and i completed my paper in 2 hours . Then i wrote as many questions as i can for telling here .Physics :In SHM at position of maximum displacement what is minimum( options were velocity , K.E. , acceleration )Velocity of an object with respect to itself in mirrorWhich of the following has highest elasticity ? ( Options Copper Glass Rubber or Steel )Kinetic Energy relation with temperature in an atom ( Directly proportional to T )A question of Ring Electric field direction at a point in its planeVelocity of COM when two bodies are moving due to gravitational attraction ( ans is zero )Formula of debroglie wavelengthRatio of radius of two particles in magnetic field ( using formula r=mb/bq)Bullet gets embedded in a block , find final velocity ( momentum conservation )On melting density of water ( options : decreases , increases , constant , depends on mass )A bullet is moving in a train of acceleration a vector , what is acceleration with respect of man on ground ( options were a , a+g , a-g , -a)Question on finding first maxima for single slitElectric Field of Ring formula based questionThis one was somewhat tricky , it was given that An EM wave is incident on an atom , if electrons are forced to vibrate in frequencies different than natural frequency then which electrons will have highest frequency ( options were like inner shell , outer shell .. )Simple Pascal Law formulaBody rolling down inclined plane find accelerationElectric field of Infinite sheet = mg ( this is solution , question was to find sigma for which this happens , i hope you got the idea )Magnetic field between two infinite long wires ( directions and data was given )Work Energy theoremFinding phase difference from path difference ( for finding wavelength equation of travelling wave was given )Value of g 32 km above earth surface ( useful data was given )This was one more tricky question , a pipe filled with air was given then it starts rotating what will the pressure at curved surface ( less than p , more than p , same , depends upon radius …. p was initial pressure )Simple YDSE question only formula substitutionU=3nrt was given find Cp/CvA simple question on Buoyancy where weight and apparent weight was givenA simple question on vector laws , four options were given we had to tell incorrect one ( options were like A.(B+C) = A.B+A.C ,,, and some more )Another question on electric field of two half rings of opposite charge densitiesEasy Moment of Inertia QuestionNLM questionPotential energy = mghFree Expansion temparture change ( ans 0 )Kinematics simple question ( relative motion )Projectile question ( on max height )A question on errorsCapacitance in an AC circuit for max power ( 1/wc = wL )A question on optics .. refractive index decrease what happens to focal length and resolving powerA bob was filled with water with a hole , as time passes water gets less , what happens to time periodOther 3 questions were too simple so i skipped them as diagram was thereNow lets come to ChemistryNo. of Proton and neutrons in O2-Nessler Reagent used for identification of which reagent ( NH4+)Multimolecular layers found in ( Physisorption )pH of a buffer solution , equal conc of salt and acid was given ( Ans was simply pka)Leaving group ability of I- , Cl- , F- , Br-Suspension of slaked lime in H20 is called ?One simple solid state questionThis one was tricky : K4[Fe(CN)6] is a ( options were mixed salt , double salt , normal salt , complex salt )Aspartame is ? { Options were something like sweetener drugs etc )Simple question in solution only delta T = Kb* m was asked only formula not even value was asked ..Ecell of a reaction ( Reduction potentials were given like Zn-> ZN2+ and Cu->Cu+ )Mole concept simple questionHVZ reaction used for ? ( alpha halo acids )seperation of crude oil into its fraction requires ? ( options were evaporation , distillation and some more )Cyclohexane stability order ( options were boat , chair , half chair , twisted )Spin magnetic moment of electronWhy Xe forms fluoridesTwo compound given relation between them asked ( option diastereomers , identical , enantiomers )Ionic Formula based questionSurface Tension question on work doneNernst Equation simple questionConformersIUPAC simple questionBe2C hydrolysis produces ( options were c2h2 , ch4 , and two more )Iodoform test identificationPeriodic table easy questionThermochemistry easy question just like asked in this year mainsWhat is Alizarin ( options were some dyes , i marked azo dye )Other questions were too easy so i did not write them also i was running out of time as i was left with 30 minutes for bonus question so i skipped writing questions in which structure or diagram were givenMaths was so easy that i did not find it worth to write , extremely easy only one question was somewhat good which wasA probability ditribution was given with P(X=x) = 1/(e*x! ) find mean of X ( options were e , 1/e , 0 and one other which i forgot )I completed bonus questions also in 15 minutes and wrote bonus questions also for you ,Spin only Magnetic Moment of [COF4]-2A reaction follows Langmuir Adsorption isotherm . What will be the order of reaction with respect to reactant at high pressure ( options were 1 , 0 ,2 ,3 )How many electrons in CL- have magnetic moment zeroA long calculation based question on depression in freezing pointPower in travelling wave string formula ( [math]0.5 u w^2 A^2 v[/math] )Square given find magnetic field at centre ( four wires were passing through corner direction was given )A boy is rotating a ball with charge q , now magnetic field is turned on in vertical direction what will happen to tension in string ( decrease , increase , depends on direction , const )A simple question with answer helical path with increasing pitchAgain maths was very easy here no point in writing . I submitted my exam and left exam centre 8 mins before completion . My computer got disconnected also two times but my data was not lost neither was time . If you have any other doubts comment down below , hope my answer could help you in some way in your exams . Just go there and do question fastly , do not waste time!!Finally my score was 374 , I lost marks in english because i did not know any antonym synonym type questions i marked randomly in those . There were 2–3 questions in maths whose answers was also not matching with any choice . My marks in mains were 256 .Now i have to go to study for advanced wish me luck for it :) .Edit 1 : Chemistry is updated now . Regarding my memory power , no i did not remember every question i wrote them behind my admit card as i know they take rough pad ;) . My whole admit card was filled and no space was left so i could not go for english ( sorry for that )Edit 2 : I did not write maths but i will try to remember some questions .Integration of [math]logx[/math] ( ans [math]xlogx -x[/math] )Two points of triangle given , centroid given , find other pointA equation in complex number was given modulus was asked ,, I put i (square root -1 ) in it and it satisfiedTangent of a parabola was given like [math]y=2x +c[/math] , c was asked ( use information of slope )In probability questions on dices was asked one was out of four dice one is heads on both side , now we toss a coin four time it show always what i probability it was bad coin ?Another question of probability which came in my bonus was very easy , probability of less than 5 was asked given number is oddIn P&C a question was asked which had two bags 5 balls in each no. of ways to choose 6 balls if we have to choose atleast two from bothA good hyperbola question was asked . From centre asymptotes were made , then make any tangent on hyperbola let it cut them on P and Q , OP*OQ was asked where O is centre in terms of a and b ( options were [math]a^2 + b^2[/math] , [math]a^2-b^2[/math] etc )A determinant question was asked where answer was zero .A quadratic question was asked where roots was given and a relation between roots was asked in terms of a , b and c ( it was easy just sum and product formula )A simple linear differential equation question , divide by x and it becomes LDE just solve it .Another differential equation question , easier than previous one , just shift x and y and you get answer .A circle with centre at origin and radius 2 was given , find equation of chord of contact from [math](4,0)[/math]A trigonometry equation was given , just change [math]cos^2[/math] into [math]sin^2[/math] and it becomes a quadratic in sin , solution was asked in [math][0,2pi][/math]A very good question was asked in height and distance , i could not solve it but i eliminated two options . It was something like a point A was given and B was given elevation of both were 30 and 60 to a tower but A and B was not on a line B was some distance ahead and above of A .. Height of tower was asked . As i had eliminated two options i marked randomly rather than solving and wasting time on it .In bonus questions a function was given as [math]f(x^2) = x^5[/math] , find derviative at x=4A simple Limits question which could be solved by applying L hospital two times or series expansion[math]\int_{-2}^{2}[1-x^2][/math]A simple question on algebra . Basic concept of Modulus of a fuctionDifferentiation of [math](sin\theta +cos\theta )/(sin\theta -cos\theta )[/math]A problem involving concept of products of slope = -1 for perpendicular linesA question of 3D in which equation of a plane was asked and a point on it was given a line perpendicular to it was also givenA good question on area in which area between a parabola its tangent at a point and x axis was askedA question on AM>GM was also asked the question was to find minimum value of (a+b)/c + (b+c)/a + (c+a/b) , first it looked unsolvable to me but then it striked to me that whenever we can not find max min by differentiating or by traditional methods go for AM >GM .. after splitting terms we can easily reach answer .Value of sin15 degree was askedFinally feel free to ask any other doubts in comments i will try to update here as i can not comment and No , i did no solve any mock tests before bitsat . I have stopped studying after mains .Update : No questions from Metallurgy were there in my slot . I did not use any special pen , simple black ball point pen and admit card .

VERY LONG answer [32+ pages].HCoV-19 (SARS-CoV-2) is very infectious (Each person infects 1.4–6.77 others), but rarely fatal for healthy people age 0–59 (maybe <1%).Recovered people may have 20-30% (or more) lung damage. One patient needed a double lung transplant. Even if you don’t die, COVID-19 scares many doctors.Flu doesn’t usually cause so much life-long lung damage.Main danger for people under 60 is pre-existing conditions - high blood pressure, diabetes, hypertension, heart disease, and cerebrovascular disease (maybe 6–23% fatality for people age 60+ or with pre-existing conditions).Most infected people show no symptoms (possibly 40–70%, but we need better studies). Diamond Princess cruise ship: 62% of infected people leaving the ship showed no symptoms. In Italy, 44% of laboratory-confirmed cases have been asymptomatic.Of people with symptoms, fever is more common at age 20–59 (85–91%) than at age 0–19 and 60+ (70–81%). Roughly 9–30% have no fever.Healthy children and teens can be infected. One study (N=2,141) shows3.0–10.6% severe/critical cases. Possible lung damage after recovery.94.2% (2,016/2,141) asymptomatic, mild, or moderate cases.It’s rare for them to be hospitalized, but if they are, it’s just as bad as for old people.Young adults ages 20-44 rarely have fatal cases, but ~20% of symptomatic cases require hospitalization, and ~2-4% require ICU.Kills more men (64%) than women (36%).Mask usage: Chinese advice is “Wear masks in public”.Coronavirus can travel twice as far as official ‘safe distance’ (4.5 meters) and stay in air for 30 minutes. (3/9/20) May stay in air for 3 hrs (3/17/20).HCoV-19 half-life on Cardboard is 3.5 (2–5) hrs. Be careful receiving packages. If package has been touched within 24-48 hrs, maybe use a disinfectant wipe (or wet soapy cloth). (3/9/20–3/17/20)Some pets can catch HCoV-19 (cats, dogs, tigers). Hong Kong is placing pets in veterinary surveillance or quarantine for 14 days if someone has HCoV-19. (3/4/20)How long does immunity last? UNKNOWN.Common cold coronaviruses usually confer weak immunity, which often fades within a year. MERS & SARS immunity lasts many years.Impact of HCoV-19 is similar to OC43 (one of four other mild “common cold” coronaviruses, 15% severe, 0.2% death), but more fatal for older people.HCoV-19 is the virus name (formerly known as SARS-CoV-2, 2019-nCoV, or “novel coronavirus”).COVID-19 is the name for the disease if you have symptoms.It’s very confusing. I don’t like the HIV/AIDS naming approach where the virus and the disease have different names.Other good sources to read:(1–2) Tomas Pueyo has amazing diagrams in his two Medium posts. Best analysis I’ve seen. Warning: Some historical dates and numbers in his diagrams and text are incorrect/out-of-date, but the essence of his concepts is good.(a) Coronavirus: Why You Must Act Now (3/11/20)(b) Coronavirus: The Hammer and the Dance (3/19/20)(3) Best introductory COVID-19 video I’ve seen (3/21/20).Takes you step by step through an illness - mild, moderate, severe, and critical. Some information is out-of-date/incorrect, but it’s a great start.This is what having the novel coronavirus looks like pic.twitter.com/mu7Sj1pq28— Tech Insider (@techinsider) March 22, 2020For people with a strong scientific background, read #4, 5, & 6:(4) Unlike #1–3 which were produced by non-experts…and have many minor errors and out-of-date information, this is 99–99.9%+ accurate (as far as I can tell).---Novel 2019 Coronavirus SARS-CoV-2 (COVID-19): An Updated Overview for Emergency Clinicians---I made three short collections of excerpts at:(4a) Some cool tables & diagrams (Easy to read for everyone)https://www.quora.com/q/coronavirus/Novel-2019-Coronavirus-SARS-CoV-2-COVID-19-An-Updated-Overview-for-Emergency-Clinicians-03-23-20-EB-Medicine/comment/1471753(4b) When to Test, Lung Ultrasound instead of CT, Drugs, Vaccineshttps://www.quora.com/q/coronavirus/Novel-2019-Coronavirus-SARS-CoV-2-COVID-19-An-Updated-Overview-for-Emergency-Clinicians-03-23-20-EB-Medicine/comment/1471880(4c) Interesting tidbitshttps://www.quora.com/q/coronavirus/Novel-2019-Coronavirus-SARS-CoV-2-COVID-19-An-Updated-Overview-for-Emergency-Clinicians-03-23-20-EB-Medicine/comment/1471927(5) Tirumalai Kamala's answer to What is the big deal about the new coronavirus, COVID-19? is good to read about top unanswered issues.(6) Dr. Muge Cevik has curated a collection of favorite papers (78) in a multi-thread tweet (Jan 28, Feb 28, Mar 22) from 1,250+ HCoV-19 papers. Mitchell Tsai's share in COVID-19: Top 25 - MTPeople age 20–54 have low fatality (0.1–0.8%), but many are hospitalized (14.3–28.3%) or need an ICU (2.0–10.4%).- Yes, Young People Are Falling Seriously Ill From Covid-19 (Bloomberg, 3/18/20)- ATAndyBiotech on twitter- Ed Taboada's answer to As a medical professional, what is your biggest concern about COVID-19?How bad is COVID-19 if you have a severe case?Read A Medical Worker Describes Terrifying Lung Failure From COVID-19 — Even in His Young Patients — ProPublica (3/21/20). Many more details than I’ve posted here. Scary. Chinese doctors were reporting similar scary experiences in January. It’s why people put Wuhan under quarantine on Jan 23. Often stories from doctors were censored so that people wouldn’t panic.“I spoke to a respiratory therapist there [New Orleans], whose job is to ensure that patients are breathing well. He works in a medium-sized city hospital’s intensive care unit…Since last week, he’s been running ventilators for the sickest COVID-19 patients. Many are relatively young, in their 40s and 50s, and have minimal, if any, preexisting conditions in their charts. He is overwhelmed, stunned by the manifestation of the infection, both its speed and intensity. The ICU where he works has essentially become a coronavirus unit.”‘I have patients in their early 40s and, yeah, I was kind of shocked. I’m seeing people who look relatively healthy with a minimal health history, and they are completely wiped out, like they’ve been hit by a truck. This is knocking out what should be perfectly fit, healthy people. Patients will be on minimal support, on a little bit of oxygen, and then all of a sudden, they go into complete respiratory arrest, shut down and can’t breathe at all.’“It’s called acute respiratory distress syndrome, ARDS. That means the lungs are filled with fluid. And it’s notable for the way the X-ray looks: The entire lung is basically whited out from fluid. Patients with ARDS are extremely difficult to oxygenate. It has a really high mortality rate, about 40%. The way to manage it is to put a patient on a ventilator. The additional pressure helps the oxygen go into the bloodstream.“Normally, ARDS is something that happens over time as the lungs get more and more inflamed. But with this virus, it seems like it happens overnight. When you’re healthy, your lung is made up of little balloons. Like a tree is made out of a bunch of little leaves, the lung is made of little air sacs that are called the alveoli. When you breathe in, all of those little air sacs inflate, and they have capillaries in the walls, little blood vessels. The oxygen gets from the air in the lung into the blood so it can be carried around the body.“With our coronavirus patients, once they’re on ventilators, most need about the highest settings that we can do. About 90% oxygen, and 16 of PEEP, positive end-expiratory pressure, which keeps the lung inflated. This is nearly as high as I’ve ever seen. The level we’re at means we are running out of options.“It first struck me how different it was when I saw my first coronavirus patient go bad. I was like, Holy shit, this is not the flu. Watching this relatively young guy, gasping for air, pink frothy secretions coming out of his tube and out of his mouth. The ventilator should have been doing the work of breathing but he was still gasping for air, moving his mouth, moving his body, struggling. We had to restrain him. With all the coronavirus patients, we’ve had to restrain them. They really hyperventilate, really struggle to breathe. When you’re in that mindstate of struggling to breathe and delirious with fever, you don’t know when someone is trying to help you, so you’ll try to rip the breathing tube out because you feel it is choking you, but you are drowning.”- A Medical Worker Describes Terrifying Lung Failure From COVID-19 — Even in His Young Patients — ProPublica (3/21/20).The US news cycle is slowly discovering the stuff which encouraged people to put Wuhan under quarantine on Jan 23. COVID-19 can be MUCH worse than most flus and colds. We’re lucky it doesn’t affect kids very much.Just because you don't feel sick, doesn’t mean you are safe to other people.“March 10 estimate by a group of scientists, published in the Annals of Internal Medicine, of the incubation period of the virus.As Vox’s Brian Resnick explains, “you can see that nearly everyone who develops symptoms of Covid-19 shows them around 10 to 15 days after the infection, and the majority get symptoms by around five days.”- 11 coronavirus charts everyone should see (Vox, 3/17/20)How to make your own masks.Do-It-Yourself (DIY) hand sanitizer not recommended.Laboratory tests by City University showed 80-90% of the function of regular surgical masks for filtering aerosol and droplets.- Make your own mask: Hong Kong scientists reveal temporary solution to shortage (2/14/20)“Mixing it at home, you can't control how the alcohol gets diluted in the final product. If you don't use enough aloe gel, it will dry out the skin on your hands, which can cause it to crack or bleed (the same is true if you just pour rubbing alcohol on your skin).But if you don't use enough alcohol, the final product won't be as effective at killing germs as store-bought hand sanitizer -- rendering it basically useless according to some experts.You can also contaminate your batch with bacteria by not using clean tools to mix it together.”- No, you shouldn't make your own hand sanitizer (CNET, 3/5/20)Update 3/24/20: HCoV-19 may be active on surfaces for 17 days or longer.Please watch the news for further updates."SARS-CoV-2 RNA was identified on a variety of surfaces in cabins of both symptomatic and asymptomatic infected passengers up to 17 days after cabins were vacated on the Diamond Princess but before disinfection procedures had been conducted"- CDC says coronavirus survived in Princess Cruise ship cabins for up to 17 days after passengers left (CNBC, 3/24/20)- Public Health Responses to COVID-19 Outbreaks on Cruise Ships... (CDC)What should I do when receiving packages or shopping?Mitchell Tsai's answer to Hello I'm not trying to panic but my question is I ordered a package from China before the outbreak is this package safe for me to open once it gets here I know a lot of people are wondering the same thing? in Coronavirus WatchWhat happens to kids?New American Academy of Pediatrics study (3/18/20)3.0–10.6% severe/critical cases. Possible lung damage after recovery.94.2% (2,016/2,141) asymptomatic, mild, or moderate cases.WHO-China Joint Mission report:~49% critical patients die~15–20% severe patients become critical- https://www.who.int/docs/default-source/coronaviruse/who-china-joint-mission-on-covid-19-final-report.pdf (2/24/20)- New analysis of coronavirus risk: Young adults are not invincible - STAT- Epidemiological Characteristics of 2143 Pediatric Patients With 2019 Coronavirus Disease in China (American Academy of Pediatrics, 3/18/20)Also posted as Mitchell Tsai's answer to What scientific studies have been done on kids with COVID-19?Soap works better than hand sanitizer.Why Soap Works (New York Times - 3/13/20)Update 3/13/20: History of HCoV-19.New info shows cases back to Nov 17 - a Hubei resident age 55 (first seafood market case was Dec 8), and they are still tracking backward to “person zero” - maybe infected Nov 14 (or earlier).- China’s first confirmed Covid-19 case traced back to November 17 (3/13/20)Genetic studies by four research groups estimate HCoV-19 infected “patient zero” in Aug-Nov 2019.----Conclusion: Wuhan seafood market transmission was probably caused by people who were already sick with COVID-19. Not from food eaten there.“Patient zero" could have caught it at the Wuhan seafood market Aug 1 - Nov 7, 2019, and then they (or other people) could have come back in December.Note: Longer history and genetic information towards the end of this answer.How does HCoV-19 (SARS-CoV-2) compare to 1918 Spanish Flu and Seasonal Flu?- graph is based on older 2/11/20 data (N=44,672)- mitchelltsai on Twitter (mitchelltsai on Twitter) (picture is from a Tweet by Seb Allaman - @AllamanSeb)- Newer 2/22/20 data (N=55,924) has CFR 3.8% (was 2.3%), and Age 80+ 21.9% (was 14.8%)- 11 coronavirus charts everyone should see (Vox, 3/17/20)At peak shedding, people with HCoV-19 emit over 1,000X more virus than SARS, which explains the rapid spread of HCoV-19.Infected people develop antibodies quickly (6-12 days), which may be why 80% of people infected do not develop severe disease.- People 'shed' coronavirus early, but most likely not infectious after recovery (3/9/20)A mathematical model suggests maybe 26% (0–32%) of people catch HCoV-19 from others who haven't had any symptoms yet (in a model with R = 2.5).Update 3/16/20: European CDC says other models suggest 48–62% asymptomatic transmission.In Italy, 44% of laboratory-confirmed cases have been asymptomatic.- Disease background of COVID-19 (ECDC)Analysis of serial intervals in 425 cases. Data from a cluster of cases in Germany suggest the proportion might be higher than 26%.- The Contribution of Pre-symptomatic Transmission to the COVID-19 Outbreak (3/2/20)In Singapore and Tianjin, infection was transmitted 2.55 and 2.89 days before symptom onset (on average).Estimated serial intervals are shorter than incubation periods, suggesting pre-symptomatic transmission.“The mean incubation period was 7.1 (6.13, 8.25) days for Singapore and 9 (7.92, 10.2) days for Tianjin. Both datasets had shorter incubation periods for earlier-occurring cases.The mean serial interval was 4.56 (2.69, 6.42) days for Singapore and 4.22 (3.43, 5.01) for Tianjin.We inferred that early in the outbreaks, infection was transmitted on average 2.55 and 2.89 days before symptom onset (Singapore, Tianjin).The estimated basic reproduction number for Singapore was 1.97 (1.45, 2.48) secondary cases per infective; for Tianjin it was 1.87 (1.65, 2.09) secondary cases per infective.”- Transmission interval estimates suggest pre-symptomatic spread of COVID-19 (3/2/20)How can we control the spread of HCoV-19?This mathematical model estimates…"To achieve control of 90% of outbreaks, 80% of contacts needed to be traced and isolated for scenarios with a reproduction number of 2.5"- Feasibility of controlling COVID-19 outbreaks by isolation of cases and contacts (2/28/20)- Coronavirus: Why You Must Act Now (Tomas Pueyo, Medium)Can I catch HCoV-19 from breathing the air near a sick person? Yes.Coronavirus can travel twice as far as the official ‘safe distance’ (4.5 meters) and stay in the air for at least 30 minutes. A bus passenger was infected 30 min after a sick passenger left the bus.This paper has been officially retracted (see below), possibly for politcal reasons.The coronavirus that causes Covid-19 can linger in the air for at least 30 minutes and travel up to 4.5 metres – further than the “safe distance” advised by health authorities around the world, according to a study by a team of Chinese government epidemiologists.Their work was based on a local outbreak case on January 22 during the peak Lunar New Year travel season. A passenger, known as “A”, boarded a fully booked long-distance coach and settled down on the second row from the back.They said the study proves the importance of washing hands and wearing face masks in public places because the virus can linger in the air attached to fine droplet particles.“Our advice is to wear a face mask all the way [through the bus ride],” they added.- Coronavirus can travel twice as far as official ‘safe distance’, study says (South China Morning Post, 3/9/20)“A paper by Chinese researchers suggesting that the coronavirus could spread farther than previously assumed through fine droplets has been retracted.On March 10, the journal posted a “statement of retraction” signed by its editorial department, without offering any reasons.The researchers also found that none of those passengers who wore face masks were infected, a finding that they said supported China’s decision to ask people to wear a mask in public whether or not they show respiratory symptoms.Before the retraction, a doctor in Beijing involved in the diagnosis and treatment of coronavirus patients told the South China Morning Post the study had left some questions unanswered.For instance, the passengers sitting immediately next to the carriers were not infected, though they were most exposed to the disease-bearing droplets known as aerosols.“Our knowledge about this virus’s transmission is still limited,” he said.- Journal retracts study on how far coronavirus can spread through droplets (Inkstone, 3/10/20)What are COVID-19 symptoms?New York Times posted a great overview article.- What Does the Coronavirus Do to the Body? (New York Times, 3/11/20)Please read. It contains many details I don’t talk about in this answer.“Here’s what scientists have learned about how the new virus infects and attacks cells and how it can affect organs beyond the lungs.”What Does the Coronavirus Do to the Body? (New York Times, 3/11/20)Excerpts from Mitchell Tsai's answer to What are the symptoms of Coronavirus?Most people have fever (87.9%), dry cough (67.7%), and fatigue (38.1%).(a) Only 4.8% have nasal congestion. It’s rare.(b) Only 11.4% have chills, unlike flu.(c) Only 13.6% have headache.(d) Some people just have intestinal upset (5.0% nausea/vomiting, 3.7% diarrhea). No fever, cough, or fatigue. It’s not common, but it happens.- https://www.who.int/docs/default-source/coronaviruse/who-china-joint-mission-on-covid-19-final-report.pdf (WHO-China mission final report, 2/24/20)“Anosmia, the loss of sense of smell, and ageusia, an accompanying diminished sense of taste, have emerged as peculiar telltale signs of Covid-19, the disease caused by the coronavirus, and possible markers of infection.On Friday, British ear, nose and throat doctors, citing reports from colleagues around the world, called on adults who lose their senses of smell to isolate themselves for seven days, even if they have no other symptoms, to slow the disease’s spread.Dr. Clemens Wendtner, a professor of medicine at the Academic Teaching Hospital of Ludwig-Maximilians University of Munich, said that the patients regained their ability to smell after a few days or weeks, and that the loss occurred regardless of how sick they got or whether they were congested. Using nasal drops or sprays did not help, Dr. Wendtner said.Now, Mr. Berry said, he literally cannot smell the coffee.“Even with a clear nose, I just realized I couldn’t smell the food that I was cooking, and I couldn’t taste the food that I was making,” said Mr. Berry, a tattoo artist based in Orlando, Fla. He was cooking a plantain dish with onions and vinegar, yet he could not smell it.”- Lost Sense of Smell May Be Peculiar Clue to Coronavirus Infection (New York Times, 3/22/20)Fever seems more common in age 20–59 (85–91%, 77–97%) than in age 0–19 and 60+ (70–81%, 48–91%).Proportion of people without fever (N=1,286, Shenzen, China, 3/3/20):Age 0–9: 30% (15–52%) no feverAge 10–19: 25% (9–54%)Age 70+: 22% (9–45%)- Epidemiology and Transmission of COVID-19 in Shenzhen China: Analysis of 391 cases and 1,286 of their close contacts) (3/3/20)N=55,924 (cases in China until 2/22/20…from page 12):“typical signs and symptoms include: fever (87.9%), dry cough (67.7%), fatigue (38.1%), sputum production (33.4%), shortness of breath (18.6%), sore throat (13.9%), headache (13.6%), myalgia or arthralgia (14.8%), chills (11.4%), nausea or vomiting (5.0%), nasal congestion (4.8%), diarrhea (3.7%), and hemoptysis (0.9%), and conjunctival congestion (0.8%).”- https://www.who.int/docs/default-source/coronaviruse/who-china-joint-mission-on-covid-19-final-report.pdf (WHO-China mission final report, 2/24/20)Note: Many people in 2010s-2020s have body temperatures below 98.6° F (37° C).(a) 98.2° F (36.8° C) for young people(b) 97.7° F (36.4° C) for healthy older people (94–99.6° F).Know your own body temperature.“Normal body temperature is not a single number, but rather a range of temperatures. The average normal body temperature is most often said to be 98.6° F (37° C). This may have been correct when it was first determined 150 years ago. But our bodies have changed.More recent research suggests that the average adult body temperature is about one degree lower, 97.5° F (36.4° C). Older adults often have an even lower body temperature without it indicating any health problems.However, recent studies indicate that 98.2° F (36.8°C) is a more accurate average, and in older individuals it may be about 1°F lower. One small study even suggested that in healthy older patients, body temperature ranged from 94° F to 99.6° F, with an average of 97.7° F.”- When is body temperature too low? - Harvard Health (1/29/20)- Influenza kills more people than coronavirus so everyone is overreacting, right? Wrong — and here’s whyHow long before most people notice COVID-19 symptoms?Median times:Five days to be short of breath.Seven days to hospitalization.Eight days to severe breathing trouble.Perhaps 50–70% of infected people never show symptoms.Some people take 24, 26, 34, …, 94 days to show symptoms.This mathematical analysis estimates only 1% will display symptoms after a 14-day quarantine, but there is a chance.Incubation Period (from N=181 study)Median 5.1 (4.5-5.8) days to show symptoms97.5% in 11.5 (8.2-15.6) daysHypothetically:After a 14-day quarantine, 1% will display symptoms afterwardsAfter a 7-day quarantine, 21% will display symptoms- Coronavirus sufferers symptom-free for five days on average – study (Guardian, 3/9/20)- The Incubation Period of COVID-19 From Publicly Reported Confirmed Cases (Annals of Internal Medicine, 3/10/20)“The median time from their first symptoms to when they became short of breath was five days; to hospitalization, seven days; and to severe breathing trouble, eight days.”- Coronavirus Live Updates: Offers of Help Go Unanswered by China as Death Toll Grows Again (New York Times, 2/7/20)The Diamond Princess cruiseship is one of the rare examples where everyone was tested (all 3,711 people), regardless of whether they showed symptoms.- 62% (476/768) who tested positive showed no symptoms- 9% (80, 8 in Japan, 72 in other countries) later showed symptoms: US (46), Australia (10), Hong Kong (5), UK (4), Russia (3), Israel (3), Canada. 14 of the US people showed symptoms right off the boat.- so it’s down to 53% (410/768) asymptomatic (as of 3/9/20)Proportion of individuals infected by SARS-CoV-2 showing symptoms among passengers of the Diamond Princess ship (with 95% credible interval).- Adjusted age-specific case fatality ratio during the COVID-19 epidemic in Hubei, China, January and February 2020 (3/4/20)Age-group data from 4 countries:- ATAndyBiotech on twitter- Ed Taboada's answer to As a medical professional, what is your biggest concern about COVID-19?Korean age-group data from Wed 3/11/20 (N=7,755):Age 80+ 7.20% CFRAge 70–79 4.35%Age 60–69 1.46%Age 30–59 <1% (8/3,358)Age 0–29 0% (0/2,718)Overall 0.77%Male 1.19%Female 0.52%Average is heavily weighted(a) age 20–29 women(b) more females- Robin Daverman's answer to Why does Italy seem to be the most affected country by the Coronavirus?Italy age-group data from Sun 3/15/20 (N=13,323):- Coronavirus Disease 2019 (COVID-19) in Italy (JAMA, 3/17/20)- COVID-19 Case-Fatality Rate and Characteristics of Patients Dying in Italy (JAMA, 3/23/20)China age-groups - Old 2/11/20 data (N=44,672):- https://github.com/cmrivers/ncov... (2/16/20)China age-groups - Old 2/11/20 data (N=44,672):IFR (Infection Fatality Ratio) = deaths/all-infected-people-with-and-without-symptoms - includes asymptomatics, AND adjusted for underreporting.CFR (Case Fatality Rate) = deaths/symptomaticIFR for age 0–29 is lower than CFRIFR for age 30–59 is about the same as the CFRIFR for age 60–80+ is higher than CFROverall IFR 1.6% (1.4-1.8%) vs CFR 2.4% (2.1–2.8%)Age 0-9 .0094%10-19 .022% (0–0.082%) vs CFR 0.25% (0–1.3%)20-29 .091% (0.03–0.2%) vs CFR 0.22% (0.04–0.51%)30-39 .18%40-49 .4%50-59 1.3%60-69 4.6% (3.8-5.4%) vs CFR 3.8% (3.1–4.7%)70-79 9.8% (8.2-12%) vs CFR 8.5% (6.9–10%)80+ 18% (14-22%) vs CFR 15% (12–18%)- 11 coronavirus charts everyone should see (Vox, 3/17/20) - Adjusted age-specific case fatality ratio during the COVID-19 epidemic in Hubei, China, January and February 2020 (3/4/20)China age-groups - Old 2/11/20 data (N=44,672):Newer 2/22/20 data has Age 80+ 21.9% (was 14.8%) but China didn’t release age-group data for age 0–79, so this is still the best set of China age-group data.- Tirumalai Kamala's answer to What is the big deal about the new coronavirus, COVID-19? (2/17/20)- https://github.com/cmrivers/ncov/blob/master/COVID-19.pdf (2/17/20)China age-groups - Newer 2/22/20 data (N=55,924)WHO-China Mission report: CFR increased in 2/22/20 data (N=55,924) vs 2/11/20 data (N=44,672):CFR 3.8% (was 2.3%)Male 4.7% (was 2.8%)Female 2.8% (was 1.7%)No Co-morbidity 1.4% (was 0.9%)Age 80+ 21.9% (was 14.8%)CFR dropped over time from 17.3% (people admitted in 1/1-10) to 0.7% (people admitted after 1/31). Why?(1) In Jan, people got to the hospital an average of 15 days after infection. By late Feb, they got to the hospital in only 2–3 days (on average).(2) China learned better ways to keep people alive. After 7 weeks, they were on their 6th version of national patient care guidelines.- Partial summary at https://www.quora.com/q/lktjmwgkoxgvdzpp/WATCH-World-Health-Organization-delivers-update-on-the-coronavirus-as-it-continues-to-spread/comment/1361305 - Mitchell Tsai's share of "WATCH: World Health Organization delivers update on the coronavirus as it continues to spread" in COVID-19 and SARS-CoV-2 (Tue 2/25/20 8 am PT)- https://www.who.int/docs/default-source/coronaviruse/who-china-joint-mission-on-covid-19-final-report.pdf (WHO-China report, 2/24/20)Can you be reinfected? Unknown. Probably yes.If HCoV-19 is like the four other mild coronaviruses (which are probably responsible for 1/4 of all “common colds”), you can be reinfected.HCoV-19 appears similar to OC43, the strongest of the four, but seems to be more fatal for older people.(1) 4 mild coronaviruses circulate in people: OC43, 229E, HKU1, and NL63.(2) Mostly OC43 and 229E(3) OC43 is the strongest, and requires intensive care for 15%.(4) Asymptomatic: 18% OC43, 35% 229E(5) Death rate: ~0.2% (US Flu is ~0.1%)(6) Can get reinfected.- Mitchell Tsai's share of "Experts envision two scenarios if new coronavirus isn't contained - STAT" in COVID-19 and SARS-CoV-2How long is HCoV-19 active on packages (cardboard), door knobs (steel, copper), and in the air?Short version:Air: 3 hoursCardboard: 1 day, 2 days to be undetectableSteel: 2–3 days, 4 days to be undetectablePlastic: 3 days, 4 days to be undetectable- How long can the novel coronavirus survive on surfaces and in the air?(Economist diagram, 3/19/20)Excerpts from Mitchell Tsai's answer to How long does CoV19 last on surfaces?Update 3/21/20: These half-lives have changed since the 3/9/20 preprint. They come from the NEJM 3/17/20 final version.Boldface numbers are visual estimates from small graphs.Regular numbers are from text in the paper.HCoV-19 half-lives:Copper 0.8 hrs (0.43–1.3 hrs)Aerosol 1.1–1.2 hrs (0.64–2.64 hrs)Cardboard 3.5 hrs (2–5 hrs)Steel 5.6 hrs (4.5–7 hrs)Plastic 6.8 hrs (5.5–8.5 hrs)- Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1 | NEJM (NEJM final correspondence, 3/17/20)Mask Advice: Since there’s so much random mask advice…(1) Official WHO recommendations (1/29/20): https://www.thebeijinger.com/sites/default/files/advice-on-the-use-of-masks-2019-ncov.pdf(2) Other observationsMasks are NOT enough if around very sick people.In an early Chinese surgery case, all 14 people in the surgery area caught HCoV-19 even with masks & gowns. Masks are NOT enough, since the virus can infect the eye area. Goggles and full face shields are now used in hospitals around very sick people.How useful is a mask in public to help keep you healthy?Update 3/9/20: Coronavirus can travel twice as far as official ‘safe distance’ (4.5 meters) and stay in air for 30 minutes.Chinese advice is “Wear masks in public”:“…the study proves the importance of washing hands and wearing face masks in public places because the virus can linger in the air attached to fine droplet particles.”“Our advice is to wear a face mask all the way [through the bus ride],” they added.- Coronavirus can travel twice as far as official ‘safe distance’, study says (South China Morning Post, 3/9/20)US advice is “Save masks for health workers, because we didn’t make and stockpile enough masks after the WHO warning on Jan 1 (2.5+ months).”HCoV-19 is ~125 nm (0.1 μm, ~150–300 atoms) in diameter, which is smaller than the 300 nm (0.3 μm, ~400–900 atoms) size N95 masks protect against.But most virus arrives in liquid droplets.IQAir HyperHEPA room filters claim to remove 99.5% of particles down to 3 nm (0.003 μm, ~4–8 atoms) diameter. HEPA filters remove 99.95% (Europe) or 99.97% (US) of particles down to 300 nm (0.3 μm, ~400–900 atoms).If you are sick, a mask in public will help keep other people healthy.But if you have HCoV-19, you probably should be inside (self-quarantine) or in a hospital.If buying food/supplies or going to a hospital, use a mask (if you can…many infected people have trouble breathing).“Surgical masks are highly effective against large airborne droplets.These traditional masks are less effective with small droplets, as they can travel farther and in unpredictable paths affected by wind and other gusts. The droplets can be inhaled around the sides of the masks.”- Blisse Edgerton's answer to What should you know about the new strain of coronavirus in China?What treatments do people receive in hospitals?Mainly people need help breathing.About 1/4 of severe/critical people need mechanical ventilation.About 3/4 just need additional oxygen.If it gets really bad, there’s an advanced breathing machine called ECMO.Most people who get that bad don’t recover. One needed a lung transplant.Treatments given to 99 patients in Wuhan:- “Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study” (1/25/20) https://marlin-prod.literatumonline.com/pb-assets/Lancet/pdfs/S0140673620302117.pdfWhat is the status of drugs, vitamins, and alternative medicine for treating COVID-19?I’m writing a work-in-progress - 19 drugs, vitamins, and other things in clinical studies around the world. Mitchell Tsai's answer to Are there any effective natural or artificial treatments (antivirals, malaria drugs, human serum, and Traditional Chinese Medicine - TCM) against SARS-CoV-2 (COVID-19)?We don’t know 100% that anything works (e.g. confirmed in double-blinded trials against placebos). A few things seem to help, but it’s hard to tell when 75-99% of people recover anyways. So medical experts are waiting for trials with placebos.First four drugs are the most beneficial ones. #1 approved for use in China. #2–4 undergoing the most clinical trials (e.g. testing drugs against placebos).(1) Favilavir (nucleoside analog of Guanine (G), a DNA/RNA base)(2) Remdesivir (nucleotide analog of Adenosine (A), a DNA/RNA base)(3) Lopinavir / Ritonavir (protease inhibitors)(4) Chloroquine (anti-malaria - we don’t know how it works…on malaria or viruses)- T-705 (Favipiravir)- Guanine - WikipediaIf you want to try Vitamins…Vitamin A, B12, C, and D are pretty good immune boosters.WARNING: Some people have medical issues which make high doses dangerous (slight danger or even life-threatening). Please consult doctors first.There are websites which list counter-indications, but it’s DIFFICULT to find the best advice without a lot of searching and some health/medical experience.You probably want to test Vitamin D & B12 blood levels first before using them.WAY TOO MUCH LOW-QUALITY INFO out there.Vitamin C megadosing helps lighten symptoms in 85% of mild cases (N=252), but doesn’t help severe patients who have breathing issues (ARDS).WARNING: Vitamin C megadoses are DANGEROUS for some people (especially with KIDNEY and other issues, please consult doctors).“In a controlled but non-randomized trial, 85% of the 252 students treated experienced a reduction in symptoms in the high-dose vitamin C group (1g / h at the beginning of symptoms for 6h, followed by 3 * 1g / day).Among patients with sepsis and ARDS, patients in the high-dose vitamin group did not show a better prognosis and other clinical outcomes.There are still some confounding factors in the existing research, and the conclusions are different.”- Vitamin C Infusion for the Treatment of Severe 2019-nCoV Infected Pneumonia - Full Text View - ClinicalTrials.govWhat is the status of vaccines?Many vaccine candidates have been created, but they need to be tested (1 year, or 5–10 years). Some approaches are:(1) NIH & US biotech Moderna - RNA vaccine based on crown-like spikes(2) University of Queensland in Australia, CEPI - "molecular clamp"(3) Vir Biotechnology - Monoclonal antibodies (mAbs)- With Wuhan virus genetic code in hand, scientists begin work on a vaccine“Even if a vaccine were ready within a year, it would be too late to stem the current epidemic in China. But it could help other countries.Fears are growing that the Wuhan virus will spread more widely and become an established seasonal disease around the world, like the common flu.China’s extraordinary efforts to contain the virus, including quarantining over 50m people, may stave off epidemics in other countries until next winter.”“Once a vaccine has been developed in a laboratory, it is sent to a factory where it is turned into a sterile vaccine mix. This is then put into vials and tested to ensure it is not contaminated before clinical trials in humans can be carried out.She leads a group at Oxford University which is working on a vaccine against the Wuhan virus. Her group has developed a template for vaccines that can be adapted quickly for new pathogens. The researchers can make the first small quantities of a new vaccine in just six to eight weeks. In the past the process would have taken up to a year.There are not many factories that can mass-produce vaccines, so new vaccines often wait in a long queue. Aware of this problem, the American government has built dedicated manufacturing facilities that can produce vaccines rapidly for emergencies. Britain is doing something similar.On February 3rd it brought on board as a partner GSK, a big drug firm, which has agreed to lend its highly effective adjuvant to a new vaccine. An adjuvant is a special ingredient that makes vaccines more efficient by boosting the immune response—which means that fewer doses of the vaccine or a lower concentration of its core ingredient is needed for vaccination.”- The race to produce a vaccine for the latest coronavirus (Economist, 2/6/20)How long does a test take? 2–3 hrs in a lab.It only takes a few hours to test for the virus (using Real-Time PCR … RT-PCR).Why do tests sometimes take days? A backlog of other people’s tests, limited equipment, limited and tired staff, paperwork, and bureaucracy.“The CDC…can diagnose a sample in a few hours once a blood specimen reaches a designated lab.”- Op-ed: We need to prepare for US outbreak of Wuhan coronavirus (CNBC)- Real-Time RT-PCR Panel for Detection 2019-nCoV (CDC Instructions)Can pets be infected? Yes. A dog in Hong Kong has been infected.Can humans transmit HCoV-19 to pets? Yes.Can pets transmit HCoV-19 to humans? Unknown.Excerpts from Mitchell Tsai's answer to Can household pets catch SARS-CoV-2 without showing symptoms?“The World Organization for Animal Health (OIE) published a report of the emerging disease, listing this case as the first known in dogs.On Feb. 26, health officials in Hong Kong placed a dog under quarantine after hospitalizing its owner for COVID-19 coronavirus infection.Veterinarians confirmed that the coronavirus had infected the dog too after taking nasal, oral and rectal swabs, along with fecal samples.Follow-up oral and nasal samples taken on March 2 and 5 continues to test positive.Doctors and veterinarians don’t know if the COVID-19 virus has the potential to be zoonotic, or transmitted from dogs to people.Doctors believe the dog got the virus directly from its owner. However, doctors don’t know how the virus was transmitted to the dog, whether by airborne particles, direct contact or bodily fluids.In Hong Kong, health authorities quarantine mammalian pets from households with confirmed human cases of COVID-19 and place the animals under veterinary surveillance for 14 days, according to the report.”- Dog infected by coronavirus COVID-19 in Hong Kong (3/9/20)“The AFCD said experts from universities and the World Organisation for Animal Health have unanimously agreed that "it is likely to be a case of human-to-animal transmission".The pomeranian has not shown any novel coronavirus symptoms the AFCD said.All pets of people in Hong Kong infected with the coronavirus will be quarantined for 14 days, starting Friday. Two dogs are already in isolation.The other dog in quarantine belongs to a second coronavirus patient that tested negative for the virus once and will be tested again before its release.Authorities said it will continue to closely monitor the pomeranian and return it to its owner when it tests negative for the disease.”- Pet dog infected with COVID-19, Hong Kong authorities confirm - France 24 (3/4/20)How fast does the virus spread? Each person infects 1.4–6.77 othersSeven R0 estimates: 4.08 (3.37–6.77, China/HK), 1.9–3.2 (Harvard), 2.6 (1.5-3.5, London), 2.24–3.58 (1.96–4.39, Hong Kong), 3.11 (2.39–4.13, Lancaster), 2.2 (90% 1.4-3.8, Swiss) 2.92 (2.28–3.67, Guandong)4.08 (3.37–6.77, 12/31–1/5) Zhidong Cao, et al., China & Hong Kong (1/29/20)Estimating the effective reproduction number of the 2019-nCoV in China1.9 - 3.2 (1/26/20) Maximum Majumder, Kenneth D. Mandl, Harvard (1/27/20)1.4 - 3.3 (1/18/20)Early Transmissibility Assessment of a Novel Coronavirus in Wuhan, China2.6 (1.5–3.5, -1/24) Natsuko Imai, et al., Imperial College, London (1/26/20)https://www.imperial.ac.uk/media/imperial-college/medicine/sph/ide/gida-fellowships/Imperial-2019-nCoV-transmissibility.pdf2.24–3.58 (1.96–4.39, -1/21) Shi Zhao, et al., Chinese University of Hong Kong (1/23/20)Preliminary estimation of the basic reproduction number of novel coronavirus (2019-nCoV) in China, from 2019 to 2020: A data-driven analysis in the early phase of the outbreak3.11 (2.39-4.13, -1/22) Jonathan Read, et al, Lancaster (1/23/20)Novel coronavirus 2019-nCoV: early estimation of epidemiological parameters and epidemic predictions2.2 (90% NOT 95%, 1.4-3.8, based on 897 cases until 1/23/20) Julian Riou, Christian Althaus, Switzerland (1/24/20)jriou/wcov2.90–2.92 (2.28-3.67, based on 830 cases until 1/23/20) Tao Liu, et al., Guandong (1/26/20)https://biorxiv.org/content/10.1101/2020.01.25.919787v1.full.pdfWhen did HCoV-19 first appear in humans?Aug-Nov 2019 - Four genetic studiesStill looking through records for “Patient Zero”Nov 17, 2019 - 1st known case (originally thought to be 12/1/19, 12/8/19, or 12/12/19).1-5 new cases each day after Nov 17.Dec 15 (27 cases)Dec 20 (60 cases)Dec 27 (180 cases)Dec 31 (266 cases)Jan 1, 2020 (381 cases)“Government records suggest first person infected with new disease may have been a Hubei resident aged 55, but ‘patient zero’ has yet to be confirmed”- China’s first confirmed Covid-19 case traced back to November 17 (3/13/20)Estimated start dates from four genetic studies are:Sep 2019 - 26 genomes (91–214 days before 12/1/19)https://www.biorxiv.org/content/10.1101/2020.01.30.926477v1.full.pdf (Xiong et al, 1/30/20, bioRxiv)11/9/19 - 12 genomes (as early as 9/25/19, 95% credible interval)Potential of large “first generation” human‐to‐human transmission of 2019‐nCoV (Li et al., Journal of Medical Virology, 1/30/20)11/17/19 - 86 genomes (as early as 8/27/19, 95% credible interval)Phylodynamic Analysis | 176 genomes | 6 Mar 2020 (Andrew Rambaut, Edinburgh, UK, 3/6/20)12/5/19 - 53 genomes (as early as 11/6/19, 95% credible interval)https://www.imperial.ac.uk/media/imperial-college/medicine/sph/ide/gida-fellowships/Imperial-College---COVID-19---genetic-analysis-FINAL.pdf (WHO, Imperial College, 2/14/20)- 5 of first six cases known then NOT from Huanan seafood market- Amy Yu's answer to How serious is the 2019–20 Coronavirus? (Chinese CDC paper, 1/29/20)- 3 of first four cases known then NOT from Huanan seafood market- https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(20)30183-5.pdf (Lancet, 1/24/20, updated 1/30/20)- Early Transmissibility Assessment of a Novel Coronavirus in Wuhan, China (Harvard, 1/27/20)- Wuhan seafood market may not be source of novel virus spreading globally (1/26/20)- Wuhan seafood market may not be only source of novel coronavirus: expert (1/29/20)- Coronavirus: Why You Must Act Now (Tomas Pueyo, Medium)Note: JAMA Diagram is amazing, but has some history errors.First case: 11/17/19 (earlier it was believed to be 12/1/19, 12/8/19, or 1214/19)HCoV-19 (2019-nCoV) identified: 1/2/20, not 1/7/20.Sequence shared: 1/5–1/10/10, not 1/12/20.Test kits available: 1/13/20. Test was being used before 1/9/20, but “kits” might not have been sent anywhere else until later.——-11/17/19: First confirmed case. Still searching for “patient zero”.12/30/19: Dr. Ai got the results for the laboratory test she ordered. It said “SARS coronavirus”. Dr. Li told more than 100 of his medical-school classmates “7 SARS cases confirmed at Hua’nan Seafood Market”1/2/20: Wuhan Institute of Virology sequenced virus (but kept it secret)1/5/20: Shanghai medical center sequenced virus and uploaded it to GenBank - Severe acute respiratory syndrome coronavirus 2 isolate Wuhan-Hu-1, co 1/7/20: HCoV-19 (2019-nCoV) announced by Chinese authorities1/9/20: Test was used to detect HCoV-19 in 15 other patients.新型冠状病毒！武汉不明原因肺炎“元凶”初步判定_新闻_央视网(cctv.com)1/10/20: Virological announced the GenBank sequence Novel 2019 coronavirus genome1/12/20: Possible the GenBank sequence was not publicly available until this date (although deposited on 1/5/20).- How It All Started: China’s Early Coronavirus Missteps (Wall Street Journal, 3/6/20)“2019-nCoV was closely related (with 88% identity) to two bat-derived severe acute respiratory syndrome (SARS)-like coronaviruses, bat-SL-CoVZC45 and bat-SL-CoVZXC21, collected in 2018 in Zhoushan, eastern China, but were more distant from SARS-CoV (about 79%) and MERS-CoV (about 50%).These data are consistent with a bat reservoir for coronaviruses in general and for 2019-nCoV in particular. However, despite the importance of bats, several facts suggest that another animal is acting as an intermediate host between bats and humans.First, the outbreak was first reported in late December, 2019, when most bat species in Wuhan are hibernating.Second, no bats were sold or found at the Huanan seafood market, whereas various non-aquatic animals (including mammals) were available for purchase.Third, the sequence identity between 2019-nCoV and its close relatives bat-SL-CoVZC45 and bat-SL-CoVZXC21 was less than 90%, which is reflected in the relatively long branch between them.Hence, bat-SL-CoVZC45 and bat-SL-CoVZXC21 are not direct ancestors of 2019-nCoV.Fourth, in both SARS-CoV and MERS-CoV, bats acted as the natural reservoir, with another animal (masked palm civet for SARS-CoV and dromedary camels for MERS-CoV) acting as an intermediate host, with humans as terminal hosts.Therefore, on the basis of current data, it seems likely that the 2019-nCoV causing the Wuhan outbreak might also be initially hosted by bats, and might have been transmitted to humans via currently unknown wild animal(s) sold at the Huanan seafood market.”- Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding (Lancet, 1/30/20)- See discussion at Dr. Eric Feigl-Ding on Twitter- https://nextstrain.org/groups/blab/sars-like-cov (1/27/20)How is HCoV-19 changing now?I keep a daily update on HCoV-19 varieties in North America hereHCoV-19 varieties in North AmericaAs of 3/11/20, there are 47 US/Canadian genomes (44 US, 3 Canada) out of 333 genomes at NextStrain/GISAID auspice - live website that anyone can play with.Nextstrain (@nextstrain) | Twitter posts updates when they upload new genomes.- auspice (NextStrain/GISAID live website)Washington state cluster:- Second diagram is by “divergence” (not time). Viruses on the right have more mutations than the ones on the left.- auspice (NextStrain/GISAID live website)What may happen in the future?In a good scenario, HCoV-19 may become a 5th coronavirus which is a “common cold”.In a bad scenario, HCoV-19 becomes a repeat of the 1918 Spanish Flu.First wave (Jan 1918) was fairly mild and killed mostly old people 60+ and kids 0–14.Mutated into a stronger version in the second wave (Oct 1918) which(1) killed lots of 15–40 yr-olds.(2) Some people who got sick in the morning, died before dinner.(3) Not as many deaths in 40–65 yr-olds & 5–14 yr-olds.“In 1918, older adults may have had partial protection caused by exposure to the 1889–1890 flu pandemic, known as the "Russian flu"As more people are infected by SARS-CoV-2, there is a larger chance of a mutation to a more deadly strain.- Spanish flu - WikipediaMy favorite Live Update sites:(1) Coronavirus Update (Live): 126,053 Cases and 4,616 Deaths from COVID-19 Virus Outbreak (Worldometers) - Best worldwide site today. Slow on China numbers.(2) Coronavirus Dashboard - Conveniently shows continents separately (US states, Canadian provinces, Australian territories, Latin America - no Africa yet).Updates slower than Worldometers.(3) Tracking coronavirus: Map, data and timeline - BNO News - Sometimes better than Worldometers with severe/critical information, but not updated as often.(4) 2019–20 Wuhan coronavirus outbreak - Wikipedia - sometimes more up-to-date than Worldometers or BNO.(5) COVID19info.live (Great graphics, good color choices)(6) Johns Hopkins https://gisanddata.maps.arcgis.com/apps/opsdashboard/index.html?fbclid=IwAR2QBDnxetMDGn-txrIUenFwDHZnrOCnXQ1eCLNv1nkN4LZcevgB81gLVho#/bda7594740fd40299423467b48e9ecf6 - old classic(7) Baidu https://voice.baidu.com/act/newpneumonia/newpneumonia - usually most up-to-date for China(8) 全国新型肺炎疫情实时动态 - 丁香园·丁香医生 (DXY)(9) ʵʱ���£�ȫ�����ͷ����������¶�̬ (newsDOTqqDOTcom/zt2020/page/feiyan.htm) QQ