Flu shots make a difference
The days are getting shorter and the leaves are turning color. It must be time for influenza immunizations.
The Center for Disease Control began its national campaign to urge Americans to roll up their sleeves and get a flu shot whether in the office of their family physician or the local pharmacy. A spokesman for the CDC emphasized the sooner Americans receive their annual flu shot — the better.
Because the vaccine takes two weeks to protect its recipient — and three weeks is more effective — health officials and the public need to stay ahead of the virus. The CDC bases its recommendations on when flu infections are likely to become common, this year recommending people aim to get the vaccine by the end of October.
"We use the end of October because in general, in most seasons, things have begun to pick up by then," said Lisa Grohskopf, an epidemiologist at the CDC and lead author on this year’s vaccine recommendations.
The influenza virus affects the lung, nose, and throat, and can be spread from skin to skin contact, exposure to a contaminated surface, through saliva, or by airborne respiratory droplets — expelled into the air when an infected person coughs or sneezes.
In the United States, October through May is considered flu season. Most people will get the flu between late December and early March, which are typically the coldest months of the year. The cold weather combined with the low humidity allows flu virus particles to remain in the air longer, making it easier for them to spread from person to person.
It’s no coincidence that there’s an uptick in viral illness when children start back to school. The cooler weather and the close proximity to other kids make contagious illnesses more likely. Once school-aged children begin getting sick, it’s more common to see adults and younger kids catch those same viruses.
For healthy adults, there’s likely no harm in getting vaccinated earlier than the CDC recommends, and it’s certainly safer than skipping the shot entirely. As long as the flu is still circulating, it’s never too late to get vaccinated. But there will always be a little wiggle room in the CDC’s recommendations.
"Unfortunately, we don't really have a good answer for when's the best time," Grohskopf said. Despite years of government urgings to vaccinate, just 45 percent of American adults got a flu shot last year.
Children receiving the vaccine for the first time need two doses spaced a month apart before they’re protected, Grohskopf emphasized, so it’s important to start that process earlier in the year. There’s a little evidence suggesting immunity might wear off in older adults, but the CDC doesn’t have enough data to know how that risk balances with all the other complications of timing the vaccine.
The CDC recommends all people above six months of age receive a flu shot. There are some exceptions, including people who have certain allergies or who are currently sick.
While it’s recommended to get it as soon as the vaccine is available, it’s beneficial to get a flu shot later in the fall than not at all. The flu’s peak season is from December to February, although it’s also common to get it anytime between October and May.
Getting it earlier rather than later is therefore advantageous, especially if you’re a young, healthy person.
Each year’s flu vaccine is the same in August as it is in November. Each vaccine contains three or four different strains to help protect against the number of different flu strains out there, so all will be included in the vaccination, whether you get it at the end of summer or closer to the winter.
Since the vaccine is based on manufacturer predictions, sometimes the predictions don’t get it right — and even when they do, they aren’t a guarantee that you won’t get sick. This is why people can still get the flu even if they’ve been vaccinated. The CDC estimates that — in years where the vaccine and viruses are “well-matched” — the vaccine reduces the risk of flu illness by 40 to 60 percent.
Doctors recommend that everyone — old, young, and even pregnant — get a flu shot, so don’t wait. Around 200,000 people get hospitalized with the flu each year.