Statistics Canada, the Canadian government agency responsible for collating, analysing and presenting official data, recently published the results of a survey on the impact and prevalence of Long Covid among Canadians1. In addition to demonstrating how Long Covid can impact people’s lives and giving some indication of the consequences to the economy, health and education system, the publication also provided some data on the incidence of Long Covid among people who’d had more than one COVID-19 infection.

This has been the subject of debate for some time, with many vocal commentators falsely reassuring the public that the likelihood of Long Covid would decrease with each vaccination or reinfection. Scientists working in the area, however, have been cautioning that the data doesn’t support this assumption2, and anyone who has studied the biological mechanisms of harm is equally cautious3.

The data from Statistics Canada suggests the incidence of Long Covid rises with each reinfection, going from around 14% in people who’ve had one infection to more than 37% in people who’ve had three4. One can argue about sample sizes, data collection and other methodological issues, but the upwards trend should give people pause, especially people who’ve been arguing that Long Covid doesn’t represent a serious ongoing risk to the population.

SARS-CoV-2 has been shown to harm almost every organ and system in the body, causing clotting, inflammation and fibrosis, impairing biological functions ranging from the mitochondria to the pancreas5,6. Given this, it shouldn’t be surprising to learn that repeated infection is likely to lead to a cumulative risk of loss of function or some form of ongoing symptoms or impairment.

When faced with the Statistics Canada report, some commentators have suggested that the data simply prove early infection with the original wild type variant of SARS-CoV-2 has a greater risk of Long Covid, but it is difficult to see how cumulative risk increases as a result of early infection. Others have called the sample size and methodology into question, but this ignores the trend, which these commentators assured the world would go down.

Others say, “This is nonsense, I don’t know anyone with Long Covid,” ignoring the fact that people often conceal health conditions and do so for a variety of reasons. Maybe they don’t want to admit to themselves that they have a problem? Or maybe they don’t want to put their job or promotion at risk? Perhaps they don’t feel comfortable sharing the knowledge with you because they’ve heard you loudly proclaiming that Long Covid isn’t real and the world “overreacted to a cold”?

Whatever the reason, the question the world now faces is whether governments are going to continue to play pretend or whether they will admit there is a problem? The US Department of Health and Human Services has recently established an advisory committee on Long Covid7 and the European Union has established a similar body8, which suggests there is some governmental recognition of the risks this condition poses. The European Union certainly recognises the number of people with Long Covid is rising8.

According to the Canadian data, since summer 2022, an additional 2 million people have developed Long Covid9. Do we really have to see millions more people join them before we act to reduce transmission by implementing clean air policies and normalizing the use of N95 respirators in society?

The Chief Science Adviser to the Canadian government believes the data tells us something that should concern us all and has joined the WHO and others in advising people to avoid repeat infection10,11. In the face of a highly infectious airborne pathogen, without a coordinated government response that mobilizes all of society, how are people supposed to do that?