Flu Isn’t the Only Condition with a Season

It’s painfully clear, from the frenzied media reports to your case load, that we’re heading into the heart of influenza season. A new report from Columbia University’s Department of Environmental Health Sciences, published in PLOS Pathogens, claims there’s a seasonality to many other infectious disease states as well, however. Many of those identified in the report are likely to present to urgent care centers. The paper identifies 69 diseases that have a fairly distinct “season,” including some caused by various parasites; those caused by bacteria; and viral diseases like chickenpox. Often, the reason for the seasonal element is self-evident; Lyme disease is more prevalent in the summertime because that’s when people across the country are most likely to be outside interacting with nature, but also because of the life cycle of ticks. Winter weather conditions allow the influenza virus to thrive, but also keeps more people inside in close quarters, where they’re more likely to infect each other. The reason for seasonal ebbs and flows was not to obvious for other maladies, however; herpes tends to be more prevalent in the spring, for example, for reasons the researchers could not identify. The actual Calendar of Epidemics is available on the PLOS website.