If you’ve felt sick with a sore throat, headache and runny nose at any time over the past year and a half, Covid-19 was the gold standard. But with public health measures easing in many places and more people traveling, we can expect a variety of other respiratory viruses to reappear this fall.
The flu practically disappeared in Ireland last winter. And the paucity of hearing people hack and the absence of sniffing individuals in the community was proof that cold viruses were not actively spreading among us.
Physical remoteness and the wearing of masks have been responsible for this drastic change in seasonal disease patterns. But some familiar viruses are showing signs of resurgence, while others wait behind the scenes for the perfect time to recover.
A single confirmed case of influenza was recorded in the Republic for the whole of 2021. This is 7,776 fewer cases than in the same period in 2020
The return of the children to school after the long summer break marks the start of cough and cold season. Coronavirus and rhinovirus spread quickly in young children, and judging by reports from parents and teachers, these cold viruses are on the rise.
For young children, respiratory syncytial virus can cause serious illness. That too all but disappeared last winter, but GPs are starting to see an increase in cases again. The latest infectious disease report from the Health Protection Surveillance Center shows 150 cases of respiratory syncytial virus were recorded here during the week ending October 9. Wheezing, lethargy, persistent cough, and difficulty breathing in an infant are all signs that medical treatment is needed.
Some fear that the lack of exposure to respiratory syncytial virus over the past year may surprise some children’s immune systems. Careful hand hygiene and other protective measures against Covid-19 could be crucial to help protect infants against respiratory syncytial virus.
The only virus with a permanent question mark over its intentions is the flu. A single confirmed case of influenza has been recorded in the Republic for the whole of 2021, according to the Health Protection Surveillance Center. That’s 7,776 fewer cases than the same time in 2020. We usually get a glimpse of the upcoming flu season by looking at Australia and New Zealand during their winter. But the Antipodes have seen low influenza activity again this year, possibly due to Covid-19 blockages. But countries in Asia, sub-Saharan Africa and South America have seen increased transmission of the flu in recent months.
Predicting influenza activity this winter is a gamble. Researchers warn to expect the unexpected. “If someone tells you they know, they don’t know,” epidemiologist John Paget of the Netherlands Institute for Health Services Research in Utrecht told Nature magazine. But most experts agree that the flu will eventually rebound, especially as travel restrictions ease.
Respiratory viruses each have their own patterns, and there can be interactions between them. The spread of one, for example, can reduce the infectivity of another
Seasonal flu typically kills 290,000 to 650,000 people a year worldwide. But for most of 2020 and 2021, it simply disappeared from much of the globe. Australia has recorded no deaths from seasonal flu so far in 2021, compared to 100 to 1,200 in previous years.
The main unknown in this year’s flu equation is how international travel will influence its resurgence. So far, the gradual lifting of social interventions to curb Covid-19 has not started the decline in influenza. The flu has continued to circulate at low levels in the tropics, so you would expect a spread from there as borders reopen and international travel returns.
What if there was a resurgence of Covid-19 that corresponds to the return of influenza to pre-pandemic levels? Respiratory viruses each have their own patterns, and there can be interactions between them. The spread of one, for example, can reduce the infectivity of another.
Whatever the outcome, it would be worrying to see rebound effects caused by a build-up of immunologically naive people in seasonal flu. That’s why it’s especially important to get the flu shot this season, now available from general practitioners and pharmacies.
Read: Flu shot for kids: everything you need to know