Paulo writes:

Hi, Vincent. I guess you might remember me: I am a Virologist/ Professor at the Veterinary College, University of São Paulo, Brazil;  I was one of the guests in the 1st TWIV episode in Brazil in 2011 and I talked a little about my work on Avian coronavirus.

Currently, my lab joined a task force to run tests on human patients for Sars-CoV-2 detection.

In Episode 598, you discussed a manuscript  on the susceptibility of cats to Sars-CoV-2 infection (Jianzhong Shi et al. (

This manuscript is causing major issues in the Veterinary community here and for pet owners, as cats are being abandoned and some private vet labs are already selling Sars-CoV-2 detection for companion animals.

The manuscript has plenty of flaws, which I summarized in a Letter to the Editor for Nature (where that manuscript was highlighted in the News section last week).

Thank you for your time and attention and for making my driving hours in São Paulo more useful.

Here goes the letter:

Cats and Covid-19:  extraordinary evidence still pending

Paulo E. Brandão

University of São Paulo, Brazil

It’s with a deep concern that I followed the outcome of Jianzhong Shi et al. manuscript ( on the experimental inoculation of cats with Sars-CoV-2, reported in this journal (

After intranasal inoculation, Sars-CoV-2 RNA was found in fecal samples and tissues of both inoculated and sentinel cats and authors suggested cats should be a target to control COVID-19 in humans. Detecting viral RNA after virus inoculation cannot be interpreted as replicating virus, as the inoculum might remain on the site of inoculation or be excreted via feces without replication.

Nonetheless, authors show virus antigens on enteric and respiratory tissue of cats using immunohistochemistry with rabbit anti-SARS-CoV-2 nucleoprotein monoclonal antibody; cats are known to be ubiquitously infected by Feline coronavirus, and the use on non-specific pathogen-free animals could cause interference with these results; it’s noteworthy no mention to viral antigen survey on dogs, ferrets, pigs, chicken and ducks, also included in this trial, is made by the authors.

Virus transmission to a sentinel cannot be promptly interpreted as active infection, as the inoculum itself may “roll” from animal to animal, and this could also result in antibodies and virus reisolation

Host-range studies are invaluable to guide control measures for Covid-19, but precipitated news might lead to the election of scapegoats.


Paulo Eduardo Brandão, PhD

Department of Preventive Veterinary Medicine and Animal Health

School of Veterinary Medicine, University of São Paulo São Paulo, SP, Brazil

Vamsee writes:

Thank you for keeping up updated about the Coronavirus pandemic. 

My question today stems from a bunch of reports suggesting that dogs and cats testing positive for coronavirus. I do not know if they are actually infected and the virus causes symptoms in them too but it is to be expected as SARS1 was shown to cause diffuse lesions in cats and dogs. Could you please shed some light on this? If cats and dogs are infected and show symptoms or do not show symptoms, could they become another reservoir host that could potentially make coronavirus a more seasonal virus? 

Thank you,


Anonymous writes:

Hi guys,

I’ve been a long time listener as found you a few years back when I had to sub at the community college where I moonlight for extra money for a microbiology lecture on viruses and needed to brush up (really loved the one on polio, got me hooked on your podcast!).

I have basically just been getting my news from y’all, am off social media except for IG so I can follow all my yoga people, and don’t spend much time on the web or watching anything on TV.   I live in east TN and am a high school chemistry/biology teacher.  I really appreciate the shout outs you have given to teachers the past few weeks.  I really think the general population does not understand what public school teachers face on a daily basis and I don’t think professionals or higher ed people realize where public ed is right now (a dark, dark place based on profits and churning).    I live in a right to work state which basically means it is a right to fire state and we have no due process and tenure means basically nothing. Living in the Bible Belt and having a masters in evolutionary ecology is not often all that great a fit (evolution? climate change?  sex ed?) and has gotten me into ‘trouble’ over the year with parents and admins more often than I like to talk about. Also, the general disregard for science in American culture is magnified living where I do. Not to mention teaching teenagers all day is hard especially with their brains being rewired by their phone addictions along with the general issues they all face (I feel very bad for teens and think they get a bad rap in general).  Add in poverty, hard home lives, poor nutrition, video game addictions and often their lack of physical exercise it isn’t as glamorous (lol) a job as most people think.    However, despite all this I love my job, I love the kids, I love teaching science and I keep coming back although every year gets a little harder and I dream of owning a small coffee shop surrounded by a lot of books.

I know you are getting lots of emails from doctors and scientists so mine may seem small but I do get asked ALL THE TIME what I think so I had a few questions.  

I have to shop for my 90 year old mother.  She is in great health as she is a Greek immigrant but we don’t want her going to the stores since she grew up in the Great Depression and the places she likes to go have no real policies in place to reduce exposure (i.e. she wants to go to Walmart and the Dollar Store).   I get everything from Trader Joes right now but she likes her Folgers coffee and Mayfield fudge bars.  I went Wed to a grocery store and it is elderly day and I decided to wear a handkerchief.  I have a zillion of them because I am a girl scout leader and we seem to accumulate them.  I use them religiously when I mow the yard for allergies. They are cotton or cotton/poly blends.   Also, it is fun because I look liked a grey haired middle aged bandit.   So, I wore one shopping to protect the other elderly people in the store.  When I got in the car I took it off and put in a bag to wash and then used hand sanitizer which I despise but alas it is what it is right now.  The handkerchief is doubled over and I know it isn’t PPE but this has to be pretty good right for a 20 minute store trip?  

Also, you’ve mentioned the air droplets and suspension time but I’m curious why humidity and warmer temps slow down the coronavirus (if I was understanding correctly from podcast last week).  Is it just natural cycle of them (prevalent in northern hemisphere in Spring and run course by mid summer)? It just seems humidity would keep the droplets in the air longer wouldn’t it?  I know heat slows down microbial growth but wasn’t sure how that applies to the coronaviruses in general.

Last but not least, we aren’t seeing a lot of the virus in our area.  If you google stats for TN these include large cities like Memphis and Nashville.   Is there a chance that we won’t have a lot of cases and if that is true does that set us up for next year being a big issue for our area?  If we get hit hard our health care system which is the pits as it is won’t be able to handle it.  My dad was in ICU before he passed last summer and they barely had a bed for him then. Not that I think my community isn’t going to be hit hard by this coronavirus because statistically it is almost for sure but could there be pockets of the population that do not get much exposure and if this does happen what could potentially be the consequences (good or bad)?  This is how mothers sleep at night.  I know you virologists are clairvoyant right 😉

Okay this was way too long.  Thanks for listening.

Thanks for your great podcast!  I really enjoy it. It almost makes me feel like I am a real science person again when I listen to it.  

Polly writes:


I’ve recently found your podcast and have really enjoyed listening to all the latest updates about the coronavirus pandemic. I’m an American citizen but I live in Vietnam and teach Biology at an International School. I’ve learned so much from your podcast! It’s also been interesting to hear how other countries have been responding to the current coronavirus. I haven’t heard anything yet about Vietnam (though I haven’t listened to everything) so I thought I’d share what I’ve experienced here.

Vietnam responded very quickly and closed schools immediately following the Tet holiday so students have not been in school since the middle of January. As a private International school we have continued to run school virtually, but local schools have been completely closed. For a long time we had only 16 reported COVID19 cases and all patients recovered. During this time, we were still allowed to go out and most businesses remained open. But within the last three weeks there has been an increase in cases as people returned home to Vietnam from other countries. Now the airport is almost entirely shut down and the government has closed most work places other than the essentials, such as grocery stores, gas stations, pharmacies, etc. Everyone is required by law to wear a mask in public or can be fined. Also, any building with an internal air conditioning system must turn it off and use fans instead. I should add that toilet paper hoarding was not an issue here because all toilets come equipped with what we like call a “bum gun,” which is basically like a hose you use to wash off with after using the toilet 🙂

What I find interesting is the way the government has kept track of all the cases. They have a system where you are classified as F0 (a person who test positive with COVID19), F1 (a person suspected of having COVID19 or a close contact of F0), F2 (a person who is close contact – less than 2 meters for more than 15 minutes – of an F1), F3 (a person in contact with F2), and F4 & F5 (a person in contact with F3 & F4). I’ve attached the diagram, but it’s in Vietnamese. Each level has a different quarantine procedure from hospitalization to a quarantine camp to self quarantine at home. Levels F0 to F3 are monitored by the local CDC. To me it seems like they really have traced a lot of the cases accurately – I was even contacted as an F4 at one point because they thought I had been in an apartment building with a COVID19 case (but it turned out I was in a different block of the apartment and so was cleared). Several people I know have been contacted and classified from F1 to F5. 

As of this week Vietnam has about 230 confirmed COVID19 cases and there are about 70,000 people officially in quarantine (including about 300 US citizens according to the US embassy). Two people I know were in quarantine camps in Ho Chi Minh City where we live. The camps seem like they have varying degrees of comfort from videos and pictures I’ve seen but seem livable (easy for me to say, I wasn’t actually there). My friends had basic Vietnamese meals delivered to their rooms, were provided with cleaning supplies and a mosquito net, had fans, and were allowed to go outside. They said the people working there were all very friendly. The biggest frustration was about how long the test results were taking – they were supposed to come back in 24 hours but were taking more than 48. If the test took too long, they had to have a second test and wait again. Unfortunately, I’m not sure what kind of testing they are doing. After two negative tests, both of my friends have been released. 

Anyway, that’s what’s been going on here from an expat perspective! While I’m sure that 230 COVID19 cases is not perfectly accurate, it does seem like Vietnam has responded well to the outbreak and that the number of cases is still pretty low for the time being. I don’t get the sense that this number is low due to lack of testing or purposeful false information, but I’m sure there are some here who would disagree. Personally, I feel safe and am happy to be in Ho Chi Minh City rather than in the US right now! 

Thanks again for the podcast – learning more about SARS-CoV-2 and virus epidemiology in general has really helped me to process and cope with things in such uncertain times.

Wishing you all the best, 


Michael writes:

Hi TWiV Team,

I’m writing to you from sunny Oahu, Hawaii with a few comments on the local situation and a set of resources that are (in my opinion) quite helpful to understand the scope of the current situation at the epidemiological altitude. 

First, the local sitrep: 285 cases, 2 deaths, with cases on all but two of the seven inhabited islands. Oahu is the epicenter with 206 cases here.

We are beyond fortunate to have a PRACTICING ER DOCTOR as our wonderful Lieutenant Governor. Dr. Josh Green has been our local Tony Fauci, giving updates on the situation every day via his Instagram feed. He’s been straightforward with us from the start while reassuring that we’ll get through this together. He keeps a whiteboard that shows the “nightmare” projection curve over which he plots actual cases by day. This shows how our social distancing efforts are flattening the curve. Here’s a brief video of his update today. I feel these are a perfect example of effective, honest, concise communication in a pandemic: updates on hospital capacity, ICU bed usage, even ventilator availability!

But enough about local responses – you’re scientists, let’s talk data.

The Centre for Mathematical Modelling of Infectious Diseases at the London School of Hygiene and Tropical Medicine maintains a repository on GitHub where they publish models that they’ve been working on. They cover several very interesting topics related to COVID-19, and they update most of them with varying degrees of frequency

On your last episode, an emailer asked, “Can we take number of deaths, divide by an assumed fatality ratio of 1%, and estimate the number of cases?” That’s exactly what the team did in one of their models, only they adjusted deaths for the distribution over which it takes most patients to pass away. They can then compare the country’s estimated range of actual cases to the number of confirmed cases to get a sense of what percentage of cases each country is actually diagnosing. Spoiler: most countries are under 20%. The US is at around 16% at time of writing and Italy is just under 6%. This would put the US at around 1.2M cases right now, which certainly “feels” quite a bit more intuitive than the official 189,000 figure. I suspect there are many, many people who were told to monitor their symptoms but who were not tested due to lack of available tests.

At the other end, Germany is around 50%, South Korea is at about 70%, and smaller outbreaks like Norway, Israel, and Australia are estimated to be at or near 100% (which hints assumed fatality rate might actually be a bit high).

They also have fascinating plots of estimated effective reproductive rate by country over time, as well as a model specific to Italy (though unfortunately these haven’t been updated in a week or so):

I highly recommend checking back on this page from time to time to see updates to the models. Adam Kucharski is also a FANTASTIC follow on Twitter.

One more tool to plug: this interactive visualization shows growth in cases and deaths by day and country (or state in the US/province in China) using the Johns Hopkins dataset. Users can choose linear or log scale; show aggregate numbers, daily increases, or relative population; and even apply exponential or logistic curves to the data. It’s a beautiful tool, I use it multiple times a day:

Please let me know the next time any of you come to the islands, your first mai tai is on me!


Chaim writes:

On TWiV 596, “Arthur in Oxford” asked if people with SARS-1 antibodies might have some protection from SARS-2. Here is a preprint that screened 51 hybridomas from transgenic mice that were raised against the SARS-1 spike protein. Four were reactive with SARS-2 spike by ELISA, and one was cross-neutralizing:

Here is another preprint that addresses the reverse question. They studied 8 SARS-2 patients; plasma from 7 of them cross-reacted with SARS-1 spike on ELISA (and 3 with MERS spike, as well), but there was essentially no cross-neutralizing:

In the same episode, Trevor asked about return to work protocols, and the TWiV team discussed resolution of symptoms versus the cessation of infectivity. Here is a preprint that tested both PCR and “live virus isolation” (sorry, Vincent). Their results suggest that (at least in mild cases) convalescent patients may no longer be infectious after ~10 days from symptom onset, despite continuing to be PCR-positive:

Thanks from brisk and breezy DC, where it’s 51*F and sunny this morning,


Liping writes:

Dear TWiV,

I want to share with you data from Taiwan. The discharge criteria used there is 3 consecutive negative tests, and the data is distributed between 8 to 53 days, with 24 being the median. They noticed that even with antibody, there is still a detectable level of the virus in the respiratory track, which is apparently unusual.

Also today, 51 recovered patients in Korea tested positive again. People thought it might be an effect of the faulty testing. Some scholar seems to suggest that chronic infection with this virus is a possibility. 

Best Regards,

Bai Liping

Elizabeth writes:

My friend, a clinical lab scientist, recommended your podcast when I first started freaking out about the novel coronavirus, and I feel so much better informed than I ever would have been otherwise. 

A few questions for you. 

1. Has there been any report of increased sense of smell or taste as a symptom of COVID-19? I am recovering from what I believe to be a mild case of it, although I didn’t qualify for testing, so I can’t be sure. The biggest discrepancy in my symptoms from what are typical for COVID-19 was that my sense of smell became significantly more acute. I could smell everything. Has this been observed in any COVID-19 patients that you are aware of?

2. You have mentioned several times that contrary to popular belief, viruses do not typically mutate to become more virulent. That being the case, what was the reason for the second wave of the 1918 flu pandemic being worse in the fall than the first wave in the spring? That seems to be the popular example in the media for a virus getting more dangerous. 

Thanks for the excellent education you’re providing! I sent a small donation in appreciation for the work you’re doing. 


Elizabeth, located in the hill towns of Berkshire County in Western Mass.

Amanda writes:

Hi all,

Long time listener, sometimes writer. Love you guys, and have been sharing all the recent SARS-CoV-2 stuff with friends. Very helpful to answer all the most common questions, and you’ve gained a lot of listeners from my people J.

I am the provincial co-lead for SARS-CoV-2 diagnostics in Saskatchewan, Canada. In Canadian public health labs we rely heavily on lab developed tests, especially in the molecular world. These do not need to be Health Canada approved, and any clinical microbiologist involved in molecular is well versed in design, development, and rigorous validation of these assays. Because of this, as soon as SARS-CoV-2 reared it’s head, all the public health labs in Canada began developing their own assays, and having weekly meetings to discuss progress, optimization, which assay is best, etc. This is why we were all well situated to test early and often. Currently, in a province of only 1,000,000, we are running just over 800 tests per day and planning to ramp up. Biggest hurdle for us is swabs to take the samples, and extraction reagents. It shocks us that your provincial labs are not allowed to do this.

Because of the Canadian experience of developing LDTs for SARS-CoV-2, I believe I have some insight into the CDC kit issue. I won’t name company names, but many of us at various labs across Canada received contaminated primers or probes at the beginning. For example, our RdRP forward and reverse primers were contaminated with E template. Another lab had an E probe contaminated with RNaseP template, and another with RdRP template. These caused various effects depending on contamination level – either late false positives with CTs around 37-40, or in our case, high CTs for E in every well, including the non-template control (PCR grade water).

Based on what little they’ve said about their issues, it kinda sounds like they had the same problem.

PS: Don’t hate on the millennials so much, at 36 I’m considered in that group and all my friends are settled with kids and houses and sore backs, and aren’t out partying and spreading the virus!

PPS: Vincent – someday I still expect a USB with your lectures on it so I can send to my old colleagues in Papua New Guinea 😉

Amanda Lang, PhD D(ABMM) FCCM

Clinical Microbiologist – Virology, Immunoserology, Molecular Diagnostics

Roy Romanow Provincial Laboratory (RRPL) – Regina

Saskatchewan Health Authority | (306) 798-4153

Cheryl writes:

Will SARS-CoV2 survive freezing? And for how long?


Thank you. You all are rockstars! (You’ve always been; the rest of the world just noticed. ) I know you’re really busy these days, so I leave it at that. 

Be well!

Sincerely, Cheryl. 

Anonymoose writes:

[ad: BCG has been part of China’s standard vaccination protocols for decades. If it’s protective against COVID-19 at all, it can’t be a very strong effect.]

Hello twiv crew. I think this would be a great question for Brianne to address. I recently saw Bob Gallo dropping hints about an old vaccine on MSNBC and I’m guessing this is what he was talking about. 

Stay safe,


Benjamin writes:

Hi TWiV team,

Came across this article today, where they say they’re conducting a trial to see if the BCG vaccine protects against SARSCoV2 in healthcare workers from Melbourne, Australia.

Don’t really understand how it might work, but the BCG vaccine can have all sorts of off-target effects that I don’t think are very well understood (like it’s use in bladder and colorectal cancers)

If the BCG vaccine is shown to be efficacious it’ll be interesting to see what that means for places it’s still in routine use



Marc writes:

Hi TWIV or possibly Immune,

My question is about immunity duration.  Coronavirus and rhinoviruses, the common cold, are the same Class IV ssRNA+, and I’ve always thought our immunity to rhinoviruses only lasts a couple of years, but I’ve noticed in your podcasts, you expect coronavirus immunity to last close to a lifetime.  Why would two viruses from the same class confer such different immunity durations?  Is it the proofreading on the coronavirus that minimizes variances, or something else about the virus or something about our immune system?

Your podcasts have been the best thing on the internet for years; I’m so glad you are finally being recognized by a wider audience, just a shame it took a pandemic to do it. 


Nathan writes:

Do most disease cures for animal diseases often apply to humans and animals?

Ati writes:

Dear TWiV team,


I’m an organ transplant surgeon in Dublin. I discovered your site almost by accident while browsing about coronavirus a week ago and I have since been addicted to the podcast. I’m afraid I might turn into a virologist

My question for you is why is COVID-19 pandemic hasn’t been so bad in sub Saharan Africa so far? Any scientific explanation or is just the pandemic lagging behind and the worst is ahead of us.

I appreciate your opinion and much grateful for your commitment to science.


Ati Ferede


Dr A. Ferede, MD, MPH, FRCS 

Kidney Transplant Fellow

National Kidney Transplant Service

Beaumont Hospital, Dublin


Robert writes:

Hi You Viral Maniacs,

If the selection pressure for the evolution of viruses is transmission, then viruses that are very good at transmission and that kill the hosts will end up with no hosts to infect. Thus I would 

conclude that selection must be based on both transmission and host survival.

What’s your take on this.

Best regards



Vic Australia

Vic writes:

Dear All,

This is Vic, the currently unemployed Cruise Ship Agent in Kristiansand, Norway.  

My wife, Beate (who is an avid TWiV listener), is an ENT Surgeon at the Sørlandet Sykehus (Southland Hospital) here in Kristiansand.  Last week her hospital published two models that attempt to predict the coming peak of hospital admissions. I have attached that presentation to this email.  I, together with Google, translated the most pertinent parts of the presentation.

Beate is wondering what you might make of these projections.  She wants you to know the following about the conditions under which the projections were made:

1.  This hospital is the only medical care facility for a stable population of 310,000 people.  The nearest neighboring facilities are 2.5 hours away.

2.  All 310,000 are covered by health insurance and unemployment insurance, so there is no penalty for staying home.  Consequently, they are staying put in their homes. The streets really are empty

3.  All the day care centers, educational institutions, gyms, sports clubs, barbers, beauty parlors, etc… are closed and have been since 13 March 2020.  Basically, everything that would require more than 5 people to congregate is shut down.

4.  All Norwegian borders are closed and travel out of the municipality of Kristiansand or across State borders is prohibited.

5.  Norwegians trust their government institutions and comply with the rules.

6.  Multi-generational households are rare.  Even the very old have their own homes or apartments.  The kids move away from home as soon as they are out of high school at 19.

Given all the above, this is an ideal population to test the limits of social distancing and makes the sort of modeling in the attached study as accurate as possible given what is currently known about the spread of Sars Cov 2.

As you can see from the charts, with an Re (R0 after measures taken on 13 March) of 1.19 they are showing peak admissions on July 13, with an Re of 1.35 the peak is 26 June.  Either way, a return to “normal” seems to be much farther in the future than current American forecasts would indicate.

My wife would like to know if you all think these scenarios are realisitc.  Can the R values really be that low? Or, is the Hospital being overly optimistic?

Beate also translated the attached document with the current status of the pandemic here in Norway.

Beate also wants you know that TWiV has many, many new listeners here in Kristiansand because she is sharing the show with all of her colleauges.  They are all very, very thankful for the information you are providing. Keep up the good work!



Elizabeth writes:

Dear TWIVians, 

Kudos to all for all, especially Vince’s interview of Ian Lipkin.

I’ve recommended this podcast so many times I decided to make the recommendation part of my standard email signature.

It was distressing to learn at the beginning of episode #596 that you have been recipients of impolite criticism.  I am appalled that anyone who invests as little as 5 minutes in listening doesn’t simply feel gratitude. Please pay no mind to such rudeness. 


Zabby/Elizabeth Hovey

Current favorite uplifting video – a city honors its most famous performing artists.

Best source of scientific information about the novel coronavirus:  TWIV, This Week in Virology. 

Aviva writes:

Hi TWiV,

Thanks for all you do. My social media just alerted me that HEPA filters are made of tiny glass threads. If this is true, please don’t cut them and then breathe that in! Here’s the PSA I saw about why we shouldn’t make masks out of those vacuum cleaner bags.

Stay safe,


Alison writes:

Hi TWiVers!

Thank you so much for your podcast.  I have listened for years and love it. I have my Virology students listen to it each week as well to keep current on things. The coronavirus info is necessary and great, but I do look forward to when things get back to normal and y’all can discuss papers again. Here in north GA it is a beautiful 75F and sunny. We have enough pollen to choke a horse, though.

So, I have a question about making masks at home. There have been patterns floating around where you take vacuum cleaner bags and cut/sew them into a mask, the idea being that the vacuum bag will filter the air out. I myself am not really familiar with vacuum bags and how well this would or wouldn’t work. Do you have thoughts? It seems as though every day is different from the one before with regards to cases, spread, and recommendations. In Feb I was telling my students that we were all fine, it was in China, nothing to worry about. Now we’re all sheltering in place. Still, the Samuel L Jackson poem “Stay the F*** Home” is a great way to laugh. Thanks for all that you do. Thank Daniel and Ori, too.


Alison Kanak, PhD

Assistant Professor, Dept of Biology

University of North Georgia

Leonid writes:

Dear TWIV team,

My name is Leonid, and I am writing from the San Francisco Bay Area, where the weather is more or less the same year round, so I don’t notice it.

I am writing because on a recent TWIV, a listener asked about the difference in the public health response in South Korea and the US. It seems to me that the question should be posed broader, as this is a difference not between South Korea and the US, but between South Korea, Singapore, Hong Kong, Taiwan and Japan on one hand, and the US, Italy, Spain, France, the UK, Germany etc. on the other. I think there are three components to the answer:

1. Expert and media opinion at the outset. Thinking back to January, there simply was not much concern about COVID-19, including among many public health experts. I do not blame them; I think this is a consequence of what we all observed previously with SARS, MERS, and flu epidemics, which originated elsewhere (chiefly in East Asia), but never took hold and never reached pandemic proportions. We humans tend to expect that the past will keep repeating itself and viruses from other continents will just stay there. Countries in East Asia, on the other hand, have had to face these emerging viruses seemingly every few years.

2. Staggering incompetence at the CDC, apparently at many levels. (I don’t know about Europe, but would not be surprised to find similarly atrophied agencies). While many experts who deal with public health tangentially may not be paying attention, it was the job of the CDC to be ready for the worst. From what I can tell, this is more than just a failure of a few leaders, but is more likely to be a long-standing institutional problem, complete with stockpiles which have not been maintained for many years, refusal to test patients on purely legalistic grounds, an inability to either design or even aliquot a PCR test correctly, and a leader who should be the public face of the response but has to be replaced by Dr. Fauci from the NIAID. (Thankfully Dr. Fauci rose up to the task. Perhaps he will agree to clean up the CDC when this is all over?)

3. Cultural differences. I doubt that many students in East Asia would be found enjoying their spring break on a crowded beach as an epidemic is sweeping across the country. A friend in New York tells me that there still are a lot of people on the street. I do not see such carefree and self-centered attitude as a problem in and of itself, but it is very harmful at times like this.

I hope that all of the above can be remedied. After all, SARS-CoV-2 is not even the worst that can hit us.

Thank you for what you do, and please keep up the important work!


Greg writes:

Dear Prof. Racaniello/TWiV Team,

Just a few quick comments/musings.

First, I was wondering how Dr. Lipkin is faring this week? 

Second, weren’t you all just thinking about this? “SARS-CoV-2 in wastewater”:

Third, I saw the following commentary in The Lancet by Dr. Gregory Poland: 

It echoes what Dr. Lipkin and others have recommended regarding a Nationwide lockdown being a prudent route to take. Unfortunately, there seems not be the political or societal will for such a wide ranging move? 

It is a real privilege to be able to freely listen to your discussions and the candid/amazing interviews with colleagues, you all can’t be thanked enough!   

Kindest Regards and Be Safe,



Gregory Burgin 

PhD candidate | Department of English: Writing, Rhetorics, and Literacies 

Instructor | Writers’ Studio

College of Integrative Sciences and Arts      

Arizona State University

Colin writes:

Dear This Week in COVID-19 hosts,

Hope you are well. I’ll keep this short, knowing you have plenty of emails to go through.

Situation in Singapore: While we initially seemed to have COVID-19 under control, the last few weeks have seen a rise in the number of locally transmitted cases and new clusters, despite gradual implementation of various social distancing and work-from-home measures. As of today 4 April 2020 we have 6 deaths reported. Yesterday, the government decided to act more aggressively and is implementing a lockdown starting Tuesday 7 April. ‘Essential’ services will continue, markets will remain open, but non-essential workplaces will be shut. Crucially, in my opinion, the government has evidently been planning for this implementation for weeks, and has coordinated across various ministries in order to roll this out in a synchronised fashion – there are websites where people can look up specifics on which businesses are essential, read FAQs, and there are channels for people to make enquiries and appeals. There is a distribution exercise starting next week whereby ‘reusable’ masks can be collected by residents (you wash them after each day, apparently).

Lancet article: While there are valid criticisms of how China has handled the outbreak, there are many lessons that can be learned from the measures they’ve taken. This article shows how 16 shelter hospitals (>10,000 beds) were set up in existing stadiums, exhibition centres in and around Wuhan in February. The diagrams and pictures tell the story. It highlights the intricacies involved in infectious outbreak control that are not immediately obvious to many people. Issues such as direction flow of healthcare workers and patients, demarcating clean and contaminated zones, having clearly defined criteria for triage – these are critical details that require significant planning and execution. It’s no wonder that hospitals can quickly become overwhelmed when trying to isolate both confirmed and suspected cases.

Stay safe!Colin Xinru CHENG | PhD Student (Prof Subhash Vasudevan – Laboratory of Experimental Therapeutics)| Program in Emerging Infectious Diseases | Duke-NUS Medical School