Flu jabs for kids ‘could curb postCovid surge’
Children are a major factor in transmission of influenza — experts
Over two years of Covid restrictions flu all but vanished, but scientists warned this week that it is on its way back — and some suggest vaccinating children is the best way to keep it in check this winter.
Schools are “breeding grounds” for flu, according to Stellenbosch University professor of virology Wolfgang Preiser, and children are a major factor in transmission and severe illness.
According to a South African study published in The Lancet Global Health journal, people without symptoms — especially children — can spread flu, which until Covid hit was responsible for 11,000 deaths a year.
According to a statement from Wits University, which was involved in the study, “young children experienced the highest burden of flu infection and symptomatic illness and were more likely to spread flu to their household contacts compared with other age groups”.
The data showed that the proportion of symptomatic infections was higher in children aged five to 18: 74% in this age group vs 39% in adults aged 19 to 44.
Dr Thinus Marais of Sanofi Pasteur, the world’s largest vaccine maker, said targeting children for flu jabs “not only has the potential to reduce symptomatic disease in this atrisk group, but also of reducing transmission in the community”.
He said: “Flu vaccination is even more important now, given that simultaneous infection with flu and Covid can result in severe disease.”
Marais said that because of nonpharmaceutical interventions such as mask-wearing and social distancing, the numbers of flu cases reported in 2020 and 2021 were reduced.
Now a resurgence is expected and Marais encouraged adults to get vaccinated too.
“In SA, annual flu recommendations encourage individuals at high risk of severe outcomes to get vaccinated. Remember that even healthy individuals who wish to protect themselves and those around them from getting the flu can consider vaccination annually.”
Preiser said it was clear “the measures used to contain Covid also worked against influenza transmission”.
These included masks, social distancing, lockdowns, and “especially school closures, as schools are thought to be breeding grounds from where influenza spreads to families and beyond”.
Whether these measures “can or should be sustained is a different question”, but Preiser said he was happy to continue wearing a cloth mask in crowded public spaces such as shops or public transport.
He said that there is much speculation about the impact of the Covid pandemic on this year’s flu season, but there is a possibility that “when influenza comes back, it could be particularly bad in terms of number of cases and severe illness because we have not been exposed for the past two years and our immunity has not been boosted naturally”.
“It is advisable to immunise against influenza every season, especially high risk groups and those in close contact with them,” said Preiser, who added that Covid and flu vaccines could safely be taken concurrently.
Preiser said another result of the pandemic in terms of flu is about vaccine development.
“It is also hoped that the experience with the Covid vaccines will help develop better influenza vaccines in future.”
Shabir Madhi, a professor of vaccinology and dean of health sciences at Wits University, said it is very likely SA will see more flu in 2022 than in the two pandemic years, but it is uncertain whether it will be worse than pre-Covid.
He said northern hemisphere experiences suggest that the flu season will be “relatively attenuated” compared with pre-Covid years.
“Nevertheless, there is no harm in people getting vaccinated, although the effectiveness of the flu vaccine is unpredictable for the upcoming season, as also evident from the northern hemisphere experience.”
According to the World Health Organisation, “efficacious and safe inactivated vaccines remain the cornerstone of influenza prophylaxis in most countries.”
In industrialised countries, influenza vaccines offer 70%-90% protection against clinical disease in healthy adults, “provided there is a good match between the vaccine antigens and circulating virus(es)”, according to the WHO.
Among elderly people not living in institutions, vaccination may reduce the number of hospitalisations by 25%-39% and has also been shown to reduce overall mortality by up to 75% during influenza seasons.