so many people were taking infection precautions against COVID-19 last year , that translated to a lower flu transmission rate as well . Fewer flu infections last year may mean that fewer people will be immune to this year ’ s strains . Combined with relaxed COVID-19 precautions , that could lead to a severe 2021-2022 flu season .”
As we know , influenza and COVID-19 are both contagious respiratory illnesses , but they are caused by different viruses . COVID-19 is caused by SARS-CoV-2 and seasonal flu is caused by infection with one of many influenza viruses that spread annually . Because some symptoms of flu and COVID-19 are similar , people may need to be tested to tell what virus is causing their illness . The CDC says it is possible to have flu and other respiratory illnesses like COVID-19 at the same time , and health experts are still studying how common this is . Some of the symptoms of flu and COVID-19 are similar , making it hard to tell the difference between them based on symptoms alone . In general , COVID-19 seems to spread more easily than flu and causes more serious illnesses in some people . Compared with people who have flu infections , people who have COVID-19 can take longer to show symptoms and be contagious for longer .
While it ’ s not possible to say with certainty what will happen in the fall and winter , the CDC says it believes it ’ s likely that flu viruses and SARS-CoV-2 will both be spreading at that time : “ Relaxed COVID-19 mitigation measures ( such as stay-at-home orders , or mask mandates ) may result in an increase in flu activity during the upcoming 2021-2022 flu season . Common respiratory viruses such as respiratory syncytial virus ( RSV ) and human coronaviruses ( not SARS-CoV-2 ) did not spread as much as usual during the 2020-2021 flu season as in past seasons . However , data from the National Respiratory and Enteric Surveillance System ( NREVSS ) showed an increase in these viruses ’ activity during the summer , outside of their usual seasonal increases .”
U . S . influenza infections are highest from October to May each year , usually peaking from December to February . While most people overcome these symptoms in three to seven days , the flu can be deadly for others . Before COVID-19 , between 12,000 and 56,000 U . S . deaths were attributed to flu annually .
“ Like COVID-19 , the flu can cause some people to get extremely sick , leading to hospitalization or even death ,” says Aaron Milstone , MD , MHS , associate hospital epidemiologist for Johns Hopkins Hospital , professor of pediatrics at the Johns Hopkins University School of Medicine , and pediatric infectious disease specialist at Johns Hopkins Children ’ s Center . “ To prevent this , it is crucial that people ages 6 months or older get the flu vaccine as soon as possible . Like all vaccines , it does not offer 100 percent protection from the viruses — but it can greatly reduce the severity of the illness . For this same reason , we also highly recommend that all eligible people get the COVID-19 vaccine .”
While the flu and COVID-19 are caused by different viruses , they spread in similar ways . “ People can use the same prevention measures to guard themselves against both illnesses ,” says Maragakis . “ These include washing your hands frequently , wearing face masks , practicing physical distancing , and getting vaccinated with both the COVID-19 and flu vaccines .”
Because influenza viruses mutate every year , the flu vaccine is updated annually to provide protection from the anticipated strains . According to the CDC , it is safe to get a flu vaccine and a COVID-19 vaccine at the same time .
As we have seen , new research warns that the U . S . could experience a severe influenza outbreak after public health measures like face masks and social distancing are lifted . These measures have protected people from COVID-19 and influenza — incidence of influenza declined 60 percent during the first 10 weeks following the implementation of the measures — but is also leading to greater numbers of Americans susceptible to the flu as immunity to the virus wanes . The use of public health measures like face masks and social distancing has declined substantially since the 2020-2021 flu seasons , although not yet to pre-pandemic levels . To what extent the flu might reassert itself in the U . S . this winter likely hinges on how much these behaviors continue .
“ In the short term , measures to control the spread of the coronavirus will likely continue to suppress the number of influenza infections , but after these measures are relaxed , with greater population-wide immune susceptibility to influenza could lead to a large outbreak ,” says Sen Pei , PhD , assistant professor of environmental health sciences in Columbia University ’ s Mailman School of Public Health . “ This year , it ’ s more important than ever to get your flu shot . While we ’ re rightly focused on protecting ourselves against COVID-19 , we shouldn ’ t forget about the flu , which can be fatal .”
Pei and colleagues used a computer model of influenza A / H1 and B , which circulated in early 2020 , to quantify the reduction of incidence and transmission after the implementation of non-pharmaceutical interventions ( NPI ) in most states on March 15 , 2020 . NPIs include travel restrictions , face masks , social distancing , public education on prevention measures , and school closures . They also projected influenza transmission at the national scale over the next five years . The model used data from the CDC FluView website .
According to the model ’ s projections , as public health measures are relaxed , a large-scale influenza outbreak will likely take place . In subsequent seasons , outbreaks will also be elevated , gradually return to pre-pandemic levels . Over the last decade , U . S . influenza deaths ranged from 12,000 in 2011-12 to 61,000 in 2017-2018 . “ Our projections show that the downstream , ripple-effects of pandemic public health measures could persist for a number of years ,” says Pei .
Experts think that the longer the control measures
In the short term , measures to control the spread of the coronavirus will likely continue to suppress the number of influenza infections , but after these measures are relaxed , with greater populationwide immune susceptibility to influenza could lead to a large outbreak .”
www . healthcarehygienemagazine . com • december 2021
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