First came the cold. Now brace yourself for flu.
Hospital admissions related to the flu virus jumped sharply in Minnesota during the week before Christmas, and now state health officials are reminding those who haven’t been vaccinated — especially the elderly and those with immune system deficiencies — that it’s time to act.
The spike in cases struck relatively late in this year’s 30-week flu season, but that’s not necessarily a good predictor of how severe it will be, said Claudia Miller, manager of the state Health Department’s section on immunization, tuberculosis and international health. The severity won’t be known for a few more weeks, she said.
“We are seeing an uptick. We are still well under the levels of influenza we were seeing a year ago to date,” Miller said. “But once we start seeing this kind of an uptick, flu usually spreads pretty quickly over the next couple of weeks.”
Fewer than five patients a week have been hospitalized with the flu in Minnesota over the first nine weeks of the season, which begins in October and runs through April. But those numbers have since jumped, hitting 36 in the week before Christmas. Once the numbers start climbing like that, it’s not unusual to see them double for several weeks in a row, records show.
The FluView map from the U.S. Centers for Disease Control and Prevention shows high levels of influenza in Texas, Louisiana, Mississippi, Alabama, Missouri and Oklahoma, but minimal levels in Minnesota and the surrounding states in the Upper Midwest.
Miller said the virus is hitting younger and healthy adults hard in other states, but said officials won’t know for a couple of weeks whether that will be the case in Minnesota.
Most of the 140 million or so doses of flu vaccine this year are designed to work against three strains of the virus, according to the CDC, but about a quarter are designed to work against four strains: two type A and two type B. The vaccines generally take effect within a couple of days.
Miller said the vaccine covers the most prevalent strain of flu turning up in Minnesota. But other factors, including an individual’s immune status, influence its effectiveness. “It is a good match, but not an absolute assurance of protection,” she said.