• By DeeDee Stiepan

Decreases in influenza, other viral infections doesn’t mean those viruses have gone away

January 25, 2021
a young man sitting at his desk with a computer and holding a tissue kleenex over his nose because of a cold or sneezing, maybe allergies

Infectious diseases experts are seeing an unusual trend when it comes to influenza, and other respiratory and gastrointestinal viruses. For the first time, many viral infections other than COVID-19 are being suppressed.

"Viruses, like influenza, which causes flu, RSV (respiratory syncytial virus) that causes bronchiolitis and parainfluenza that causes croup, we're seeing really low rates of those viruses this year," says Dr. Nipunie Rajapakse, a Mayo Clinic pediatric infectious diseases expert.

Watch: Dr. Nipunie Rajapakse discusses interesting trends among viral infections other than COVID-19.

Journalists: Broadcast-quality sound bites with Dr. Rajapakse are available in the downloads. Please courtesy, "Nipunie Rajapakse, M.D./Infectious Diseases/Mayo Clinic."

"As a pediatrician, in our hospitals in the middle of January, usually we're seeing many children admitted with influenza infection or with RSV infection. And this year, we're really not seeing that at all," says Dr. Nipunie Rajapakse. "The rates of hospitalizations, the rates of positive tests for those infections among children have been extremely low, which is fortunate because those infections cause a lot of illness and deaths within the pediatric age group."

Similar trends are being seen for bacterial infections. Dr. Rajapakse says there have been fewer admissions to hospitals for children with pertussis, which causes whooping cough and other types of bacterial pneumonia.

Dr. Rajapakse says there are a few different reasons why these infections are lower than usual. One is that the measures recommended to prevent COVID-19 ― wearing a mask, social distancing, staying home when sick and frequent hand-washing ― effectively prevent the spread of other viruses and bacteria that are spread by respiratory droplets. Another factor contributing to the decreased rate of influenza is the high number of people who have been vaccinated for influenza.

"In this past year, we have seen the highest uptake of influenza vaccine than we have ever seen before. Close to 200 million doses of influenza vaccine have been distributed, and that certainly has helped to keep the rates of influenza infection low this year," says Dr. Rajapakse.

However, Dr. Rajapakse says the influenza virus hasn't completely gone away, so it should still be a concern.

"It's still really important that everyone follow the recommended preventive strategies that are recommended for COVID-19 prevention, which also help to prevent against acquiring influenza. We really have to see what happens over the next coming weeks and months. The flu season can go as long as May, so there's still quite a few months ahead of us to see kind of how things go," says Dr. Rajapakse.

Infectious diseases experts are keeping a close eye on what's happening in Australia. Often, the U.S. can look to the experience in Southern Hemisphere to predict the severity of its flu season.

"Australia, last year, also had a very mild flu season during their typical winter respiratory season. But they're now starting to see some increase in cases outside of what would be their typical influenza season. We're looking at that with some interest to see whether this phenomenon that we're seeing may end up just delaying our usual flu season, or maybe you don't have one at all this year. I think it's too early for us to say for sure," says Dr. Rajapakse.


For the safety of its patients, staff and visitors, Mayo Clinic has strict masking policies in place. Anyone shown without a mask was either recorded prior to COVID-19 or recorded in a nonpatient care area where social distancing and other safety protocols were followed.

Information in this post was accurate at the time of its posting. Due to the fluid nature of the COVID-19 pandemic, scientific understanding, along with guidelines and recommendations, may have changed since the original publication date

For more information and all your COVID-19 coverage, go to the Mayo Clinic News Network and mayoclinic.org.

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