Immunity debt is a possible unintentional side effect of the measures taken to prevent the spread of Covid. With the lockdowns, mask-wearing, and social distancing, fewer people have gotten sick. But, researchers are raising concerns. Will there be more illnesses due to future viruses than would’ve normally occurred because we are not being exposed to the germs now that would strengthen our immune systems for the future? This would seem to be the case. It is called immunity debt. As it stands now, we don’t know if the immunity debt will be great or small, though mathematical models project that it might be large.

• “Post-Covid-19, World Risks Having to Pay Off ‘Immunity Debt’ “Mathematical models by researchers at Princeton University suggest that substantial outbreaks of the RS virus and possibly seasonal flu may occur in future years, with peak outbreaks likely occurring in the 2021-2022 winter season in the U.S.” (https://aos.princeton.edu/news/post-covid-19-world-risks-having-pay-immunity-debt, underline added)

Illustration of Immunity Debt

Let’s say that you have 100 types of germs that you will be exposed to on a yearly basis. Every year your body reacts and strengthens its own resistance to germs and is more prepared for new ones.  Of course, some people are affected worse than others and some people don’t get affected at all. Those are the facts. But, let’s say that deaths related to the common flu are .08%¹Death rates of common flu, https://carm.org/covid/deaths-per-100000-covid-and-other-causes-in-u-s-population/. In 100,000 people that would be 80 deaths since the flu affects all people, young and old (Covid rarely affects the young). Now let’s say the government requires all people to wear masks and practice social distancing. Let’s say that doing so reduces your exposure to flu germs by 20%. This would mean that the overall population is less exposed to germs. In our scenario, that would mean 20% fewer deaths. That’s good. Now, let’s continue for another year. It would mean that another 20% less exposure, and so on for each subsequent year. With the decrease in exposure to germs over time, society becomes less resistant to new pathogens. The longer this isolation and mask-mandate protocol continue, the less capable a society would be of resisting new strains of the flu. We then have to ask what would happen when a strong variant of the flu materializes after a few years of mask-wearing and social distancing? Would it be a worse pandemic that is caused by their efforts to stop the pandemic? I don’t know. But, think about what happened to isolated, indigenous populations when Europeans unintentionally introduced new germs to a population. That had a functional immunity debt because they weren’t exposed to new germs. The result was catastrophic. Likewise, the potential is a deadly pandemic due to the decreased strength of resistance to infections of the overall population that is caused by isolation and mask-mandated protocols.

Quotes on Immunity Debt

• “The longer these periods of “viral or bacterial low-exposure” are, the greater the likelihood of future epidemics…Due to the decreased spread of RSV [Respiratory Syncytial Virus], this year as a result of anti-COVID-19 measures, the natural protection of the population against RSV at the end of winter will be lower than usual, raising fears of a more important RSV epidemic in the future…”  (https://www.sciencedirect.com/science/article/pii/S2666991921001123)
• “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.” (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8114587)
• “According to a study conducted in France, an immunity debt is caused by a lack of exposure to regular bacteria and viruses. All the measures taken to suppress the spread of COVID-19, such as social distancing, increased hand-washing, and sanitizing, also helped stop the circulation of other common illnesses. While it was beneficial in the short term to see the case numbers of viral diseases drop, they are expected to surge as children return to school and childcare settings.”  (https://www.verywellfamily.com/what-is-immunity-debt-and-how-may-it-affect-kids-5196462, underline added)
• “Post-Covid-19, World Risks Having to Pay Off ‘Immunity Debt’ “Mathematical models by researchers at Princeton University suggest that substantial outbreaks of the RS virus and possibly seasonal flu may occur in future years, with peak outbreaks likely occurring in the 2021-2022 winter season in the U.S.” (https://aos.princeton.edu/news/post-covid-19-world-risks-having-pay-immunity-debt, underline added)

Conclusion

So you can see that the immunity debt is a real concern. So far, from what I’ve read, scientists don’t have a way of predicting exactly what will happen. Of course, the fourth quote above talks about mathematical models. That is the closest we have to a prediction. But, it seems obvious that the means used to protect against viruses are beneficial in the short term, but can be detrimental in the long term. Only time will tell.

(Please read the CARM disclaimer regarding Covid related issues.)