Pathogens are said to be “zoonotic” if they are transmitted from animals to humans. Zoonotic viruses have recently been brought to the world’s attention by SARS-CoV-2, but their pandemic potential has long been recognized. In 2012, seven years before the start of the COVID-19 pandemic, David Quammen published Spillover, a book about several prominent zoonotic pathogens. He spent years interviewing and accompanying field epidemiologists, virologists, veterinarians, doctors, and others about emerging zoonoses, as well as intriguing nuances of familiar threats like malaria. It is a phenomenal book, and I highly recommend giving it a read. Read more...

In this post, I am covering some topics related to influenza, including antigenic shift vs. drift, immunodominance, and original antigenic sin (OAS). These aren’t unique to influenza, but they have been well characterized in influenza, one of the most common human viruses. Read more...

One of the hypothesis for why children appear to have less severe cases of COVID-19 than adults is that childhood vaccines may provide general immunity to all pathogens by boosting the innate immune system. In this post, I’m going to discuss the concepts of trained immunity and non-specific vaccine protection. Read more...

This is the third of my posts, in which I cover some of the hypotheses and research into why some cases of COVID-19 are more severe than others. Much of this information comes from clinical observations of COVID-19 patients that are correlated with poor disease outcomes, and scientists and physicians and hypothesize that these could be linked to disease progression. There is a strong push to initiate clinical trials, even small ones, so that observations can be generalized, but for now, most of the data is anecdotal. Read more...