The New York Times, March 18, 2022


As the Omicron coronavirus surge subsides, researchers are keeping an eye on a highly transmissible subvariant known as BA.2. Many epidemiologists suspect that it may reverse the decline of cases in the United States, but doubt that it will cause a large new spike.

Here’s what we know so far about BA.2.

Continue reading “‘Stealth’ Omicron Is Stealthy No More: What’s Known About the BA.2 Variant”

The New York Times, March 11, 2022


In recent days, scientists have reported that a hybrid of the Omicron and Delta coronavirus variants has been popping up in several countries in Europe. Here’s what is known so far about the hybrid, which has picked up the Frankensteinian nicknames of Deltamicron or Deltacron.

Continue reading “New ‘Deltacron’ Variant Is Rare and Similar to Omicron, Experts Say”

The New York Times, February 26, 2022 (with Benjamin Mueller)


Scientists released a pair of extensive studies over the weekend that point to a large food and live animal market in Wuhan, China, as the origin of the coronavirus pandemic.

Analyzing a wide range of data, including virus genes, maps of market stalls and the social media activity of early Covid-19 patients across Wuhan, the scientists concluded that the coronavirus was very likely present in live mammals sold at the Huanan Seafood Wholesale Market in late 2019 and suggested that the virus spilled over into people working or shopping there on two separate occasions.

The studies, which together span 150 pages, are a significant salvo in the debate over the beginnings of a pandemic that has killed nearly six million people across the world. The question of whether the outbreak began with a spillover from wildlife sold at the market, a leak from a Wuhan virology lab or some other event has given rise to pitched debates over how best to stop the next pandemic.

Continue reading “New Research Points to Wuhan Market as Pandemic Origin”

The New York Times, February 24, 2022 (with Patrick J. Lyons)


With the huge Omicron surge in coronavirus cases now receding in the United States and many other countries, reports have been cropping up in many news outlets lately about a potentially worrisome new version of Omicron — a subvariant known as BA.2 — and the threats it may pose.

Here are some key things to understand about BA.2 and what we know so far.

Continue reading “Is the BA.2 version of Omicron worse? Here’s what you need to know.”

The New York Times, February 10, 2022


In the mid-1300s, a species of bacteria spread by fleas and rats swept across Asia and Europe, causing deadly cases of bubonic plague. The “Black Death” is one of the most notorious pandemics in historical memory, with many experts estimating that it killed roughly 50 million Europeans, the majority of people across the continent.

“The data is sufficiently widespread and numerous to make it likely that the Black Death swept away around 60 percent of Europe’s population,” Ole Benedictow, a Norwegian historian and one of the leading experts on the plague, wrote in 2005. When Dr. Benedictow published “The Complete History of the Black Death” in 2021, he raised that estimate to 65 percent.

Continue reading “Did the ‘Black Death’ Really Kill Half of Europe? New Research Says No.”