The rise in mask-wearing and social distancing during the pandemic led to a decrease in the emergence of different viruses, including the flu, and to continue the trend, USF Health experts recommend getting vaccinated against all flu-like illnesses.
Associate Dean of the College of Internal Medicine Michael Teng and Edwin Michael, professor of epidemiology at the College of Public Health, emphasized the unpredictability of the intensity of the upcoming flu season and the importance of getting the flu shot this year.
Due to the precautions put in place for the pandemic, such as masks and social distancing, the flu season has gone unnoticed and had little to no impact last year, according to Michael and Teng.
In the Northern Hemisphere, the flu season takes place from October to March. In the 2019-20 season it impacted roughly 35 million Americans compared to 1,800 in the 2020-21 season, according to data from the Centers for Disease Control and Prevention. As COVID-19 positivity rates start to decline and precautions and mandates start to dissipate, other diseases, such as the flu, can potentially gain intensity as they did before, according to Michael.
After the winter flu season, the World Health Organization takes samples of the flu virus seen that season, and uses it to develop the vaccine for the following year. Since the flu season had little impact last year, Michael said less information contributed to the development of this year’s flu shot.
“Vaccine-induced immunity in flu may not carry over from one season to another, because the flu vaccines are made specific to strains which are circulating the season before,” said Michael.
However, the mutation of the flu virus might have been low this past season since cases were low, according to Michael. Due to the lack of a flu season last year, Michael said not as many people built up immunity to the disease.
“The level of acquired immunity might be too low, so you need vaccines,” said Michael. “If we increase the normal vaccination rates against the flu … normally it’s about 50%. The models were saying that you really increase the vaccination rate by about 20% more … that will prevent the large increase in cases.”
COVID-19 has impacted the health care system, leaving less room in hospitals for other patients, according to Teng. He said not taking the proper precautions to prevent the flu, like getting the flu shot, could put more of a burden on the health care system.
“To try and prevent a lot of cases of these flu-like illnesses, you want to vaccinate against all of those viruses that you can, but that won’t prevent the flu-like illnesses because a lot of people who end up in hospital with a flu-like illness don’t really know what it is until they get tested,” said Teng. “It puts a burden on the health care system as well, especially in the face of a pandemic.”
While getting the flu shot may help, people are still taking certain measures to protect themselves against COVID-19 and other diseases like it, unlike before. These restrictions can help bring down the flu cases like last year, according to Teng.
“We do still have more restrictions than we normally do, there’s people still wearing masks,” said Teng.
The true intensity of the upcoming season is unknown, so Michael and Teng said students should get the vaccine to stay protected against the virus. Getting the flu shot has even less allergy-related risks, so there is more availability for more people to get it, according to Teng.
“The great thing about the flu shot is that we used to only have a couple of ways of making the flu shot, and we’d go and they’d ask you about egg allergy, because they always grew it in eggs,” Teng said. “Now there’s different choices, there’s the flu shot that’s not grown in eggs anymore so you don’t have to worry about an allergy.”
Students can get their flu shots for free at USF clinics, and can schedule an appointment or visit the USF Health Immunization Clinic for a walk-in appointment. They are also available at the USF Health Immunization Clinic at the Morsani College of Medicine, where COVID-19 and flu vaccines are available, and at the USF Health Immunization Clinic at South Tampa Center for Advanced Healthcare, which only offers the flu vaccine.
“People don’t realize that the flu this year might be worse than [what] we’ve experienced recently,” said Michael. “It’s imperative to try and protect ourselves as best as we can, and taking the vaccines is a very safe way out in fighting flu.”