You’ve probably heard the term “twindemic” in recent months, and it doesn’t take much deciphering to get to the crux of its meaning. Heading into winter at the end of 2020, there were prominent fears that COVID-19 and flu could launch a double assault on people’s health across the world.
Much was made of what could be done to prevent that nightmarish scenario, from robust uptake of the influenza vaccine to enhanced cleaning and disinfection, strict use of PPE, and myriad other factors.
Whatever is being done to safeguard against the situation appears to be working.
Indeed, data from recent weeks from the U.S. Centers for Disease Control and Prevention (CDC) suggests the seasonal flu has all but vanished so far in winter 2020-21.
Far lower numbers
During the 2019 flu season from Sept. 29 to Dec. 28, the CDC reported more than 65,000 cases of influenza nationwide. During the same period in 2020, the agency reported just 1,016 cases.
During a typical flu season, the number of people getting the flu would just be starting to rise, with the peak typically coming in February. Yet so far, only 0.2 per cent of 400,000 swabs for the flu have been positive, according to CDC data; down 12.8 per cent from the positivity rate this time last year.
North of the border in Canada, the latest Public Health Agency of Canada influenza “FluWatch” from Dec. 13, 2020, to Jan. 2, 2021, found “no evidence of community circulation of influenza”.
“All indicators of influenza activity remain exceptionally low for this time of year, despite continued monitoring for influenza across Canada,” the report states.
To date this flu season, the FluWatch reports have tallied 92 “flu-like illness” outbreaks that were reported in schools and daycares.
And these figures are despite huge rises in testing. In the U.S., there is thought to have been a sixfold increase in testing at public health labs, most of which checked for influenza A and B along with the coronavirus.
There have been far more vaccinations than usual, too, as many of the people who may have previously been unconcerned by the threat of flu rushed to protect themselves in light of COVID-19’s alarming spread. According to the CDC, about 53 per cent of American adults have received the flu vaccines, up from 42 per cent at around the same time last year. By the end of the 2019-20 flu season, in fact, that figure was only at 48 per cent. It’s a hugely significant rise.
Public health measures working
Health experts say that those high vaccination rates are just one factor in the hugely reduced transmission rates, though. The lower numbers are largely down to a combination of intensified public health measures, as well as heightened public awareness of the way of stopping the spread of respiratory illnesses. Just as important as influenza inoculation has been social distancing, mask-wearing, hand-washing, stay-at-home advice, and the closure of many schools, offices, and other multi-resident buildings.
For example, educational institutions like schools undertaking measures to prevent the spread of COVID-19 has likely been vital. Children shed the flu virus more than adults do and for longer periods of time, making it easy to spread to family members and teachers who can spread it to other adults. “Children have been much more isolated, so this distribution mechanism has been effectively shut down,” said Dr. William Schaffner, a professor of preventive medicine and infectious diseases at Vanderbilt University.
Boiled down, the biggest difference is that people have been far less exposed to illness than usual. They are not seeing anywhere near the same number of other people in their day-to-day lives and they are interacting with far fewer high-touch surfaces with schools, campuses, offices, and numerous other public buildings either closed or seeing far lower capacities than in the pre-pandemic world.
Not only that, of course, but the standards of cleaning, disinfection, and infection prevention have soared. Air travel, too, is down by an unprecedented amount, meaning flu-type are not being spread in the typical 21st-century fashion. The southern hemisphere, which experienced the first “COVID winter” several months before the northern hemisphere, had a virtually non-existent flu season.
It’s undoubtedly a relief to see public health measures working well in stopping the usual spread of flu.
However, some experts have admitted that the numbers speak volumes about the comparative transmissibility of COVID-19. We already know the coronavirus spreads like wildfire, at rates far above that of influenza or other similar respiratory illnesses. There are multiple factors in that, including the fact that many positive cases of COVID-19 exhibit symptoms either very late in the day or, in many cases, not at all.
A welcome relief
All in all, though, it’s appropriate to be hugely grateful for the fractional flu numbers.