The phenomenon occurs where people who have not been exposed to normal levels of viruses and bacteria experience a surge in infections as normal life resumes.
New Zealand is now seeing a high number of babies becoming hospitalised for respiratory illnesses including respiratory syncytial virus (RSV), a common illness that only produces mild symptoms in adults but can be severe or even fatal for children, The Guardian reports.
Wellington currently has 46 children hospitalised with the illness and other hospitals are experiencing similar, putting pressure on the country’s health system.
In February, a paper published found that New Zealand experienced a 99.9% reduction in flu cases and a 98% reduction in RSV thanks to its coronavirus restrictions.
However, New Zealand has reported nearly 1,000 RSV cases in the past five weeks, according to the Institute of Environmental Science and Research.
The usual average is 1,743 over the full 29-week winter season.
A French paper published on immunity debt in May warned of future epidemics.
It said: “While [non-pharmaceutical interventions] NPIs limited the transmission of [coronavirus], they also reduced the spread of other pathogens during and after lockdown periods, despite the re-opening of schools since June 2020 in France.
“This positive collateral effect in the short term is welcome as it prevents additional overload of the healthcare system.
“The lack of immune stimulation due to the reduced circulation of microbial agents and to the related reduced vaccine uptake induced an ‘immunity debt’ which could have negative consequences when the pandemic is under control and NPIs are lifted.
“The longer these periods of viral or bacterial low-exposure are, the greater the likelihood of future epidemics.”
New Zealand was praised for its handling of the coronavirus pandemic. Up to 8th June, the country has seen only 2408 cases and 26 deaths.
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