July 2, 2020 - Comparing April and June Numbers
THINK LIKE AN EPIDEMIOLOGIST: There are more new confirmed cases each day in the US than at any time during the earlier April peak. But is it really meaningful to compare those numbers? How do epidemiologists decide when to sound the alarm? A thread. 1/11 pic.twitter.com/rPelzIvcxs— Natalie E. Dean, PhD (@nataliexdean) July 3, 2020
June 23, 2020 - Median Age of Cases is Dropping
THINK LIKE AN EPIDEMIOLOGIST:— Natalie E. Dean, PhD (@nataliexdean) June 23, 2020
What does it mean that the median age of new cases is dropping in some areas? I see three possible explanations, not all good. A thread on how to distinguish between them. 1/10
(Figure h/t @ScottGottliebMD) pic.twitter.com/Y6m45qoBL6
May 24, 2020 - Vaccines for SARS, MERS, and HIV
Why don't we have a vaccine for SARS? MERS? HIV? These viruses have been around longer than SARS-CoV-2. A mini-thread to provide some perspective and even a little dose of optimism. We are not in the same situation here. 1/7— Natalie E. Dean, PhD (@nataliexdean) May 25, 2020
May 21, 2020 - Heterogeneity and super-spreading events
This preprint on SARS-CoV-2 transmission dynamics was a great read. The discussion about heterogeneity often focuses on numbers of contacts, but that always felt incomplete to me. As much as possible, we must link the models to the biology. (Thread 1/7)https://t.co/ptE6KCbrC2 pic.twitter.com/76pznbAl7w— Natalie E. Dean, PhD (@nataliexdean) May 22, 2020
May 19, 2020 - ProPublica article on contact tracing
May 11, 2020 - Scientific innovations in prophylaxis and treatment
May 9, 2020 - Uncertainty in the herd immunity threshold
Seeing papers make the rounds that the herd immunity threshold may be much lower than the rough approximation 1-1/R0. Maybe, but let's slow down a minute.— Natalie E. Dean, PhD (@nataliexdean) May 9, 2020
#1. There is still way too much uncertainty.
#2. This does not qualitatively change our strategy.
My comments. 1/
May 4, 2020 - Lessons from Kerala, India
May 3, 2020 - Learning from experienced countries
In comparing outbreaks across countries, I think there is a lot of luck involved in the timing (it’s when, not if). But places that have faced outbreaks in the past have a collective memory and can respond quickly. Highlighting a few examples. 1/7https://t.co/HawqDHbUzw— Natalie E. Dean, PhD (@nataliexdean) May 3, 2020
April 23, 2020 - Positive predictive value tutorial
1/7 Lots of folks trying to understand sensitivity and specificity. Maybe the most important concept to understand right now is that of POSITIVE PREDICTIVE VALUE.— Natalie E. Dean, PhD (@nataliexdean) April 23, 2020
Given a test result is positive, what are the chances you were actually infected?
Biostats 101 primer on the topic.
April 19, 2020 - Serosurvey design considerations
1. It's easier to poke holes in a study than to run a study yourself. We should expect many more SARS-CoV-2 serosurveys in our future. So in the spirit of promoting good science, here are my thoughts on best practices for the design of serosurveys. pic.twitter.com/eIxAiaE24V— Natalie E. Dean, PhD (@nataliexdean) April 19, 2020
April 17, 2020 - Review of Santa Clara serosurvey preprint
April 10, 2020 - Clinical trials during a pandemic
Hey friends! ?? I wrote my first newspaper article.— Natalie E. Dean, PhD (@nataliexdean) April 10, 2020
In this perspective piece, I talk about the importance of randomized clinical trials even in the most challenging settings (like pandemics!). And I outline smart ways to accelerate this process.
April 6, 2020 - Scientists and clinicians hard at work
1/ There's no shortage of discouraging news out there right now. So I wanted to share a different angle. I am really proud to be part of an amazing community of scientists and clinicians.— Natalie E. Dean, PhD (@nataliexdean) April 7, 2020
A short thread on a few of my favorite things, in case you missed them.
March 29, 2020 - Harvard Business Review article on Italy
It amazes me that anyone can see the situation in Italy, see their own case numbers follow a similar trajectory, and think that watchful waiting is an appropriate course of action. We must learn from our neighbors.— Natalie E. Dean, PhD (@nataliexdean) March 29, 2020
A thread on this insightful HBR review.https://t.co/XilRJitZkK
March 21, 2020 - Intepreting percent hospitalized or died
March 17, 2020 - Creative strategies from South Korea
March 13, 2020 - Sensitivity and specificity tutorial
EPI 101 thread on sensitivity and specificity, plus its application to #COVID19 screening. For those who want a refresher!— Natalie E. Dean, PhD (@nataliexdean) March 13, 2020
The way we summarize the accuracy of a test (such as RT-PCR on a #coronavirus throat swab) is with two quantities: sensitivity and specificity. 1/12