BY KNVUL THE SHEIKH NEW YORK TIMES
WASHINGTON — As the fall winds blow, so does the annual flu season. The timing of the attack can vary, but flu cases typically begin to increase in October and peak between December and February. This year there are signs that, after two years of relative quiet, the flu may be about to make a comeback. Many protective measures taken against covid-19 that also helped control the flu have been relaxed: people travel more and wear fewer masks.
The best way to protect yourself and your family against the flu is to get vaccinated. We asked experts to weigh in on the vaccine, its side effects, and more.
The efficacy of the vaccine
Flu vaccines are updated each year based on what experts learn from previous seasons, flu patterns in other parts of the world, and estimates of how the virus might change. On average, flu shots help reduce the number of people who get sick by 40% to 60%, said Emily Martin, an associate professor of epidemiology at the University of Michigan School of Public Health.
People are also reading…
That means the vaccine can help prevent millions of flu illnesses, as well as thousands of hospitalizations and deaths each year.
According to the Centers for Disease Control and Prevention, the flu causes between 9 and 40 million illnesses and between 12,000 and 52,000 deaths each year.
In general, vaccines tend to work best against illnesses caused by a strain of the virus known as influenza B and a subset of influenza A viruses, Martin said. The shots are less effective against another subset of influenza A viruses known as H3N2. H3N2 viruses mutate much faster, and scientists’ predictions about how well the vaccine might protect against these changes don’t always match, Martin said.
Even if you get sick after receiving a vaccine, the shot can reduce the severity of the illness. Studies also suggest that the flu vaccine can help reduce community transmission.
Time and duration of protection
Immunity against the flu tends to decrease. You have better protection a couple of weeks after getting the vaccine, compared to four or five months later, so it’s a good idea to schedule your vaccination appointment close to the start of the flu season, and not too early. Martin said.
It is important to get the vaccine before cases start to rise. Your body needs at least two weeks after the injection to build up its defenses. People who are more susceptible to severe flu (older adults, pregnant women, and very young children) should not delay their vaccinations.
Most insurers cover the cost of flu shots. People 65 and older enrolled in Medicare Part B plans and most people on Medicaid can get their annual flu shots at no out-of-pocket cost. Those without insurance can access free or low-cost vaccines through state health departments, employer vouchers, or federal initiatives like the Vaccines for Children Program. Use the CDC’s Vaccine Portal to find places that offer flu shots.
People 65 and older are at high risk of developing serious complications from the flu, including pneumonia and inflammation of the lungs, which can cause shortness of breath and lead to hospitalization and the need to use a ventilator. An influenza infection can also increase the risk of heart attack and stroke in older adults, said Dr. Tara Vijayan, an infectious disease physician at the David Geffen School of Medicine at UCLA.
Older people also tend to respond less well to vaccination compared to younger adults. That’s why CDC’s Advisory Committee on Immunization Practices updated its recommendation this year that people age 65 and older receive one of three flu vaccines specially designed to better activate the immune systems of older people. Some of these vaccines have been around for several years before the recommendation was formalized. One option is the Fluzone High-Dose Quadrivalent Vaccine, which contains four times the dose of a standard flu shot. Another option is the Flublok Quadrivalent vaccine, which is created from a small piece of genetic material from the virus. The third option is the Fluad Quadrivalent vaccine, which is manufactured with an adjuvant, a substance that enhances the body’s immune response. Many doctors and pharmacists are proactively offering these options for older adults, but it’s a good idea to check when you’re going to get vaccinated, Martin said.
The CDC and the Advisory Committee on Immunization Practices recommend that pregnant women get vaccinated to protect themselves and their fetuses. Just as the body experiences immune decline as it ages, it also tempers its immune responses during pregnancy, Talbot said.
Postpartum women, even if they are breastfeeding, can receive any approved flu vaccine for their age. But pregnant women should avoid the Flu Mist nasal spray vaccine, which contains live viruses. This is because, in theory, the virus in the vaccine could infect the fetus, even if it has been weakened, Talbot said.
Children become eligible for flu shots at 6 months of age. The first time they get a flu shot, they need two doses, four weeks apart.
After that, they can get one flu shot a year, Talbot said. Children older than 2 years have the option of receiving the FluMist nasal vaccine.
All flu shots have a good safety record. Side effects tend to be mild and go away within 24 to 48 hours, Martin said. You may experience some pain or slight swelling around the injection site. Other common side effects include a general feeling of malaise, headaches, muscle aches, and nausea.
It’s a misconception that getting a vaccine can cause the flu, Vijayan said. Vaccines are designed so that the virus they contain is inactivated or changed, and they cannot make you sick.
It takes two weeks for the vaccine to develop protection, so you could get the flu in that time. You may also develop a slight fever after receiving the injection.