As I predicted a month ago the number of new COVID cases has decreased in the US. From a high of 70,000 per day to 35,000 per day now. It will likely continue to decrease for some more time.

This is due to many factors, but great national leadership is not one of them.

Why are cases decreasing even though most of us are still susceptible?

2 reasons:
— Increasing proportion of persons at high risk of getting COVID (eg., jobs where u can’t social distance) have already had COVID
— Effect of masks & distancing

But the proportion of people who have been exposed is very low even in hotspots. Less than 10%. Does this mean >90% of us are still susceptible? And if so, why are cases decreasing?…

While we have to assume that we are all susceptible and continue to take preventive measures, seroprevalence studies likely underestimate the proportion of people who have been exposed to COVID. See article by @JoshuaPCohen1 @Forbes…

But even if we do some rough math, and double the seroprevalence we will still have only estimated 10-15% of population as having been exposed to COVID, far lower than what is needed for true herd immunity, but yet cases are decreasing, even in many hot spots. Why?

Which brings us to the big question. Are we all equally susceptible to COVID? Or do some people have cross reactive immunity in which cases the disease is so mild that while you may get a PCR positive result, it doesn’t actually lead to symptoms or permanent seroconversion?

An important caveat:

-What happens in Europe happens a month later in the US. In Europe there is a 2nd wave. Our cases can go up dramatically. We have to be careful & continue masks and social distancing because that may reduce viral dose and thereby the severity of COVID
As cases come down leaders will naturally try to take credit. Or my worry is that they may tell people to relax. But to be clear the drop in cases is happening because of reduction in susceptible population and due to behavioral changes, specifically masks. @jeremyphoward

The number of daily cases now is higher than I thought it would have been at this point. But the trend is there.
My feeling is that the drop in cases will be transient and we will have another peak in late fall. But my hope is that the drop in mortality is more enduring.

I also recognize that COVID has a lot of long term consequences. So it’s important we do everything to keep cases down

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More from @VincentRK

18 Sep
Here are 4 threads on randomized controlled trials (RCT) that may be useful for those interested in doing one, or learning about the process and what it takes. #MedTwitter #MedStudentTwitter

1. The process is not easy. Certainly not for investigator initiated RCTs in the US.
2. Here is an example of the process from start to finish of an RCT we did in @eaonc @SagarLonialMD

It gives you an idea of the process for investigator initiated NIH cancer trials— which is totally different from a Pharma company sponsored Pharma company run trial.
3. RCTs can be done for various reasons including incremental advances and drug approvals. Many of these are well done by Pharma. And Pharma has the resources to pull it off. But we also need strategic investigator initiated trials to answer important clinical questions.
Read 5 tweets
17 Sep
COVID started earlier in the EU. Deaths climbed at same rate initially. Since May, however, the EU has done well while we have gone our own separate way. ImageImage
At present, there are only 2 of 27 countries in the EU with higher deaths per million compared to us: Belgium and Spain. In both places the pandemic struck early, without much warning. We are heading in a trajectory that will catch up to Spain. ImageImage
When we compare ourselves to countries in Eastern Europe, or Germany, our plight becomes clearer. ImageImage
Read 5 tweets
9 Sep
The common refrain from experts early on was that masks were not needed unless you are sick. I believed this till Mar 29. Then the evidence became too strong that masks were needed for everyone. But the message was that it was only to protect others from you (source control).
But the high rate of serious illness in healthcare workers, the lower mortality in mask wearing countries and COMMON SENSE meant masks must protect the wearer also (work as PPE). People are also more likely to wear a mask of it helps themselves not just others.
Read 6 tweets
8 Sep
For the record, I’ve been saying for months that wearing masks can make COVID infections less severe by lowering the viral exposure dose. #WearAMask

There’s a paper in @NEJM on this today.
I am trying to figure out when I started staying this. But at least as early as March 31.
Here is the @NEJM article which is outstanding. As places relax restrictions masks and social distancing are the best ways to reduce severity of infections and number of deaths. @MonicaGandhi9 @Rutherford_UCSF @UCSF…
Read 4 tweets
5 Sep
A big fall in the number of new cases and deaths per day with accompanying announcement of a vaccine will likely be the #OctoberSurprise.

The likely fall in the number of new cases and deaths is not a result of great national leadership. But simply natural course, similar to patterns in most hotspots.

200,000 lives lost is an irreversible tragic loss. Deaths could have been >70-80% lower with good leadership.

I’ve written about the possible trajectory of new cases before. I hope for our country that cases and deaths go down. We have suffered more than most countries: deaths, morbidity, heartaches, loss of life, burnout and stress of frontline healthcare workers, jobs.
Read 10 tweets
4 Sep
Behind the Scenes: A thread of randomized trials I have helped lead and publish. Each one has a story. Most have been a struggle.

This is for young physicians trying to start a career as a clinical investigator or trialist.
#MedTwitter #MedStudentTwitter #myelomaVR #mmsm

1) ECOG Thalidomide Dex vs Dex for myeloma. My first RCT. I had previously led small Thal trials at Mayo. But leading this pivotal RCT required luck. I had proposed a small Ph II, so they let me be PI. But @theNCI mandated a change to Ph III RCT design.…
2) Celgene Thal Dex vs Dex placebo RCT. Given success of ECOG trial, which led to thalidomide approval by FDA, I was asked by Celgene to lead their company trial: a confirmatory trial for regulatory approval. Company trials are easier to run.…
Read 9 tweets

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