The bug is back.

While seasonal flu viruses are detected year-round, they are most common during the fall and winter, so now (and for a few months to come) is the time to guard against the potentially serious illness, health officials say.

The exact timing and duration of flu seasons can vary, but influenza activity often begins to increase in October. Most of the time flu activity peaks between December and February, although activity can last as late as May, according to the national Centers for Disease Control (CDC).

People who are considered at high risk for serious complications from the flu older adults 65 and up, anyone with diabetes, asthma, heart disease, morbid obesity or other chronic health conditions, children under 5 years old, and pregnant women.

The CDC recommends flu shots for everyone, including infants as young as six months. People can contact their doctors or healthcare providers or county health departments for information on where and when to get the vaccinations.

A year ago in Pierce County, 42 people died and 671 were hospitalized in connection with the flu during the 2018-19 flu season, according to the Tacoma-Pierce County Health Department.

For information on flu shots, the Tacoma-Pierce County department can be contacted at tpchd.org, info@tpchd.org and 253-798-6500. And the Seattle-King County Public Health Department can be reached at 206-296-4774 and vaccineinfo@kingcounty.gov.