COVID precautions kept flu season quiet
Masks, social distancing and hand-washing lead to historically low hospitalization rate
What medical officials worried would be a “twindemic” at the end of last year — the concurrence of influenza and COVID-19 sicknesses overwhelming Houston’s hospitals — turned out surprisingly well.
At Memorial Hermann, just three patients tested positive for influenza during the 2020-2021 flu season, compared with 983 patients during the 2019-2020 flu season. Doctors test for both flu and COVID-19 as a precaution.
The same public health measures that prevent SARS-CoV-2 from spreading — masks, social distancing and regular handwashing — kept influenza strains from sickening people.
“When we were looking internally, we just weren’t seeing flu,” said Dr. James McCarthy, chief executive physician at Memorial Hermann.
Flu infections are down nationwide, with a hospitalization rate of 0.7 per 100,000 people, according to the Centers for Disease Control and Prevention. During the previous flu season, the rate was nearly 100 times higher — 66.1 per 100,000 patients. Pediatric deaths also decreased, from 189 last year to one this year.
It was a historic flu season, the lowest hospitalization rate since the federal agency began tracking flu data in 2005. If people contin
ue practicing those public health measures, experts said, flu rates could be this low every year.
Flu vaccination rates and the reduction of holiday gatherings also helped, said Dr. Luis Ostrosky, an infectious disease specialist with UTHealth and Memorial Hermann-TMC. UTHealth also saw a drop: from 2,094 patients treated last flu season to 1,215 this year.
“We’ve had barely any flu cases reported in the Houston area. The 2020 to 2021 line is almost flat compared to the big spikes we usually see in the winter months,” Ostrosky said.
About 53 percent of adults nationwide had received the flu vaccine as of mid-January, while just 45 percent had received a flu shot by the end of January 2020, according to CDC data.
Dr. Jeffeea Gullett, medical director of the UT Physicians Multispecialty Victory Clinic, estimated about 75 percent of her patients received the flu shot this year, including those who skipped in prior years. Many wanted to minimize their chances of being infected with the flu, especially before the COVID-19 vaccine was authorized for emergency use.
“We were grateful we didn’t have a lot of our vulnerable populations getting the flu,” Gullett said. “It allowed us to focus on one virus and try to tackle that as opposed to having to deal with both.”
At the height of Houston’s third coronavirus surge in late December and early January, the weekly average of new COVID-19 patients hovered just below 250 patients in the Texas Medical Center. Texas hit a new hospitalization record during that time, with more than 11,000 COVID-19 patients occupying hospital beds across the state, according to a Houston Chronicle analysis of state data.
Pandemic public health measures didn’t stop all viral sicknesses from breeding. Adenoviruses and rhinoviruses, which cause the common cold, continued to infect communities to a smaller extent. However, those sicknesses rarely send people to the hospital, Ostrosky said.
Researchers wondered whether being infected with the coronavirus would wipe out the chances of getting the flu and say it may be a factor that contributed equally to declining flu rates.
“Part of it is because we had a worse virus that was spreading faster,” McCarthy said.
Knowing to wear masks and get a flu vaccine could be a huge step toward eradicating deadly flu seasons. But will people continue to practice those public health measures? Doctors don’t know.
“We’re recognizing that not only can we protect our friends and loved ones from COVID, but we can also do it from influenza with precautions for medically vulnerable folks,” McCarthy said.