Many communicable diseases are more common during certain seasons of the year; for example, influenza usually occurs in the winter and early spring, as does chickenpox. Infection with Salmonella is most common in the summer but occurs all year round. Meningococcal infections tend to occur most often in winter. Some diseases are more common among young children, others in adults. When outbreaks occur, we make the information public as soon as possible so people can take whatever preventive steps are necessary.
(FAQ9168)
