Sept. 29, 2021 — With the Delta variant of COVID-19 nonetheless raging in the USA and intensive care models in components of the nation crammed with sufferers with the coronavirus, consultants are voicing concern in regards to the added threat of a tough flu season.
Two mathematical fashions are predicting a giant rebound within the quantity and severity of flu instances within the 2021-22 season after final 12 months’s flu season failed to point out up when public well being measures introduced in to manage COVID-19 appeared to have the additional advantage of stopping the flu.
However each analyses, posted to the medRxiv preprint server and never but peer-reviewed by different consultants, have come to the identical conclusion: The flu may make a comeback this 12 months.
Within the worst-case state of affairs, the U.S. may see an additional 300,000 to 400,000 hospitalizations from the flu — virtually double the standard quantity — in response to senior examine writer Mark Roberts, MD, director of the Public Well being Dynamics Laboratory on the College of Pittsburgh. These numbers might be a catastrophe in areas the place hospitals are already crammed with COVID-19 sufferers.
Waning pure immunity within the public as a result of final 12 months’s lacking flu season may make folks, particularly younger youngsters, extra more likely to get the virus.
“Normally, a mix of pure immunity and vaccination helps tamp down seasonal influenza,” says Roberts. “If we do not have the primary half, we’ll must rely extra on the vaccine.”
In a typical 12 months, about half of People get the flu shot. The brand new mathematical fashions predict that the vaccination fee would wish to rise to about 75% to keep away from the additional hospitalizations. However even a ten% improve in vaccination charges may scale back hospitalizations by 6% to 46%, relying on what strains are dominant.
Normally, the Southern Hemisphere flu season, from February to August, helps present what the Northern Hemisphere can count on over the approaching winter. However with strict COVID-19 measures and limits on worldwide journey nonetheless in place in international locations like Australia and New Zealand and far of South America, it has been one other document low 12 months for flu infections, says Ian Barr, PhD, deputy director of the World Well being Group’s Collaborating Heart for Reference and Analysis on Influenza in Melbourne, Australia.
Australia detected solely round 500 instances this 12 months, in contrast with about 300,000 in a traditional 12 months, and recorded no hospitalizations or deaths from the flu. New Zealand recorded simply two instances.
“I’ve by no means seen something like this,” Barr says.
In Australia, the delicate flu season led to fewer folks getting their flu shot than regular. The speed fell from round 50% to simply 33%, says Barr. “If that occurs within the U.S., the inhabitants shall be much more weak as a result of there was virtually no flu for greater than 12 months,” he says.
Each Roberts and Barr say it’s vital that as many individuals as attainable get vaccinated through the upcoming flu season, particularly youngsters who could have virtually no pure immunity to the virus.
“The vaccine is our greatest weapon towards the flu, particularly for probably the most at-risk teams,” says Barr.
Different components of the world had blended outcomes. India noticed a excessive variety of flu instances, whereas neighbouring Sri Lanka had only a few. West Africa additionally noticed fairly a excessive degree of circulating virus. General, the flu was detected in 45 international locations through the Southern Hemisphere season, lower than half of what could be anticipated in a traditional 12 months, says Barr.
Regardless of the general low numbers, the WHO noticed sufficient within the knowledge to make two changes to subsequent 12 months’s Southern Hemisphere vaccine formulation at its assembly on Sept. 24, after altering simply one of many strains for the Northern Hemisphere vaccine at its assembly final February.
The CDC recommends that everybody 6 months or older get the flu shot, with few exceptions.
