After two years of little activity, the flu could resurface this year.
The return of a potentially robust or even severe flu season has health experts concerned that we could finally see the arrival of a long-feared “twin disease” of COVID-19 and flu, which would put a strain on an already strained healthcare system.
But flu seasons are notoriously difficult to predict. (Despite concerns, there has never been a “twindemic” in recent years.)
Still, as we head into the 2022-2023 flu season, local infectious disease experts say there’s cause for concern this year could break the trend.
How bad can it be and why?
While it’s hard to predict how a flu season will develop compared to previous years, one of the mechanisms health experts use to predict what’s going to happen in North America is by monitoring how flu is circulating in the Southern Hemisphere.
“Sometimes that’s an accurate reflection … but it doesn’t predict 100 percent what will happen here,” said Dr. Larry Madoff, medical director of the State Department of Public Health’s Office of Infectious Diseases and Laboratory Sciences.
People look to countries like Australia and New Zealand to see what types are circulating and how severe their flu season is, which is typically from April to September (their winter).
Preliminary data indicate that flu cases peaked earlier and higher in Australia in 2022 than in any of the previous five seasons, and children and teens were more likely to be affected than adults, according to a recent article in The Journal of the American Medical Association. But while the country saw a high number of cases, the impact was rated “low to moderate” by the government.
The number of admitted patients with flu also peaked early, according to the publication, but not higher than in the previous five seasons.
dr. Erica Shenoy, associate chief of the Infection Control Unit at Massachusetts General Hospital, considers the early season and high number of cases seen down under as a potential indicator of what we might see in Massachusetts and the Northern Hemisphere.
The flu trends of recent years also play a role.
“We’ve seen very, very little flu,” she said. “And now that most of society is back to normal, as the cooler air comes in and people are inside more, we would expect an increase, not just in the flu, but other respiratory viruses that are circulating.”
Due to social distancing and other COVID pandemic measures, Massachusetts has seen very little flu in 2020, according to Madoff.
Then, in 2021, it was “unusual,” with flu showing up early and late, but not much in between.
“In the last few years, fewer people have gotten the flu, and that’s always a little warning sign because when people get the flu, they develop some immunity to it,” Madoff said. “And if they don’t get the flu, there’s less immunity around, and that’s especially true for kids who haven’t seen a lot of flu seasons. So that’s somewhat concerning — that less people will be immune to the flu this year and that would could give us a more severe flu season.”
The fact that many of the COVID-19 mitigation measures (such as social distancing and mask mandates) that have helped flu prevention in previous years have now been relaxed also means more flu could be seen this year.
Those factors — relaxed pandemic measures and reduced immunity to the flu — are likely at least partly behind the “extra severe flu season” in the Southern Hemisphere, Madoff said.
“We won’t be surprised if we have more flu in the Northern Hemisphere this year,” he said.
Shall we really? see the long-feared twindemic?
Madoff said it’s possible that this year’s flu season could be worse than COVID in both severity and number, as there’s likely less immunity to flu in recent years.
The state epidemiologist said the possibility of a “twindemic” is a concern and the state is closely monitoring.
“It’s something to keep in mind, and it’s a very good reason why people should get vaccinated for both COVID and flu,” he said. “There is the new bivalent booster vaccine, which almost everyone is eligible for and should get as soon as possible. And it is also time for a flu vaccine every year, for everyone aged six months and older.”
The bottom line, Madoff said, no one wants any of the diseases to be circulating, because both can cause serious illness and spread among close-knit populations, such as at school.
Shenoy, who noted that she’s been asked about the possibility of a twentiedemic over the past two years, said it’s hard to say if it could emerge this year.
“Every year we have a lot of people who could be vaccinated against the flu but choose not to,” she said. “And so if we have a combination of an earlier flu season, a more robust flu season, less immunity to previous exposure in the last two years, and add to that maybe not as good vaccination as we’d like, then we would definitely have a more influential flu season.”
She pointed out that there are still “pretty substantial levels of COVID circulating” in the Northeast.
“If the flu comes back this year with a vengeance, then we’ve got that on top of it and we need to contain it,” Shenoy said. “And hopefully over the next month people will take their time and get vaccinated so they’re protected.”
Madoff and Shenoy agreed that the concern with a twentieth century is that it could put a strain on an already heavily burdened health care system.
“Our health care system is already under a lot of stress,” Madoff said. “There are already very large numbers of patients in our healthcare facilities, and every flu season, even before the pandemic, the flu season has always stretched the capacity of our healthcare system. So we see this every winter that more people are hospitalized during flu season. , so we won’t be surprised if that happens again – and that adds to the volumes already caused by COVID.”
Preventing a flooding of the health care system is another important reason for people to get their flu vaccine and COVID booster, the doctors said.
How viral interference — a phenomenon in which contracting one virus reduces the risk of being infected with another virus — might play a role in the 2022-2023 season remains to be seen.
Madoff said viral interference may have been a factor for seeing less flu during the ommicron wave last year.
But while he said it can be difficult to get two viruses at the same time, it does happen.
“We’re seeing some people get co-infections with multiple viruses, and that’s very dangerous,” he said. “That is something that can cause a more serious illness. And while viral interference is something our bodies use to protect us from getting a second viral infection, it can still happen. You can get viral co-infections, and those infections can be more serious.”
What should you do?
Both Madoff and Shenoy stressed that the best thing you can do to protect yourself from flu season — no matter what it comes — is to get vaccinated.
It’s important every year, but Madoff said given the increased risk of a more serious season this year, it’s even more important.
He recommended rolling up both sleeves and getting your flu shot at the same time along with your COVID booster, one in each arm.
“Now is the time to get a flu vaccine,” he said last week. “Normally we urge people to get vaccinated in October. That way, their immunity is boosted before flu season hits. We’re already starting to see some flu activity in southern states, where it usually starts. Texas, Georgia is already seeing some increases in their flu rates. And we won’t be at all surprised to see it come here.”
Since both the flu and COVID are expected this year, and both viruses have symptoms that aren’t always distinguishable, Madoff said it’s important for people to stay home when they’re sick to avoid spreading the illnesses.
People should also get tested if they have a respiratory infection, both for COVID-19 and the flu, he said.
Shenoy said if you develop symptoms of the flu or COVID-19 to talk to your doctor about possible treatment.
“If you are a patient at high risk for serious illness, we can provide treatment even without a flu test if you are at high risk for complications and it looks clinically like you have the flu,” she said. “So people should definitely contact their doctor if they are concerned that they may have the flu.”
Those typically most affected by the flu are people over the age of 65, pregnant women and young children, especially under the age of 6. Children under the age of 2 are even more at risk of serious complications from the flu.
Shenoy urged parents to start vaccinating their little ones, especially if it’s their first season, as they require multiple injections.
“You want to get started on that as soon as possible,” she said. “I know some pediatric practices don’t have it yet, but you should check in to see if it’s available to start vaccinating.”
Madoff said that for the first time this year, the Centers for Disease Control is also recommending people over 65 get either the high-dose or adjuvanted flu vaccine, which induces a more immune response and provides better protection for the most vulnerable. populations.
“Everyone really should get a flu shot,” Madoff said. “And the reason is not only to protect yourself, but also to protect the people around you. So if you don’t get the flu, you don’t give it to your elderly parent or grandparent or your immunocompromised neighbor.”
The state epidemiologist noted that Massachusetts has a trend to do well with vaccination rates, both for COVID and the flu.
“We want everyone to keep doing the good work,” he said.
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