Influenza cases declined for a third consecutive week in Maine, signaling that the worst of flu season might be over.

The state had 636 new flu cases for the week ending on Feb. 24, for a total of 5,625 for the 2017-18 season, according to the Maine Center for Disease Control and Prevention. Flu is far more prevalent than the numbers show, because most people recover at home while the statistics reflect people who test positive for the virus. The total number of cases is almost certain to surpass the 5,830 from the 2016-17 flu season. Flu season typically runs from October to May.

Flu cases climbed steadily through Feb. 3, when cases apparently peaked at 876 for that week. Cases fell slightly to 831 for the week ending Feb. 10, then dropped to 793 the next week before falling to 636 in the week ending Feb. 24.

Flu is notoriously unpredictable, and there could be other surges. Nationally, this season has been among the worst in recent years, with flu widespread through the continental United States. There had been 161,129 reported cases through Feb. 17, the most recent federal data available. Flu cases have also declined nationally the past two weeks.

In Maine, there were three new deaths in the most recent week, bringing total deaths to 55 for the 2017-18 season.

The predominant strain that’s circulating is influenza A, H3N2, a virulent strain that’s more likely to result in hospitalizations.

Symptoms include fever, chills, muscle aches, swollen lymph nodes, sore throat, headaches, fatigue and coughing. Aside from immunization, basic hygiene such as frequent hand washing, getting plenty of sleep and staying away from sick people helps prevent the flu.

The flu vaccine is 36 percent effective this season, according to the U.S. CDC.

Public health officials strongly recommend getting a flu shot every season despite the varying effectiveness of the vaccine year-to-year.

For those who get a flu shot and still contract influenza, symptoms tend to be milder and not last as long, research has shown. The vaccine is never 100 percent effective because the flu virus is always mutating. In order to get the vaccine on the market in time, scientists must predict months in advance the predominant strains of flu that will be circulating. The vaccine was 48 percent effective in 2016-17 and 59 percent effective in 2015-16, according to the federal CDC.

Joe Lawlor can be contacted at 791-6376 or at:

jlawlor@pressherald.com

Twitter: joelawlorph