All infectious diseases are seasonal

Most of us are aware of the seasonal cycle of influenza outbreaks, which for Americans peak in the winter. In a new paper, Micaela Martinez, PhD, a scientist at the Columbia University Mailman School of Public Health, makes a case that all infectious diseases have a seasonal element. The “Pearl” article appears in the journal PLOS Pathogens. Martinez collected information from the World Health Organization, the U.S. Centers for Disease Control and Prevention, and peer-reviewed publications to create a calendar of epidemics for 69 infectious diseases, from commonplace infections to rare tropical diseases. A given year will see outbreaks of flu in the winter, chickenpox in the spring, and gonorrhea and polio in the summer—to name a few of the best described seasonal outbreaks. She found seasonality occurs not just in acute infectious diseases like flu but also chronic infectious diseases like Hepatitis B, which depending on geography, flares up with greater...