“Never really, but they have transformed, spaced out over time,” emphasizes Mikael Askil Guedj, doctor of medical sciences and eye surgeon, who has looked at all the diseases of the century in a book “Doctors in spite of yourself, Portraits of diseases of the 21st century” (Grasset, 2023). “It’s the epidemic genius: there are cycles of a few years, sometimes a few decades where diseases are forgotten, mutate a little, then reappear without warning.”
These diseases “have always been latent”, also notes Philippe Sansonetti, professor emeritus at the Pasteur Institute and the Collège de France. “Syphilis, we saw it flare up with AIDS and then fall again at the same time as prevention measures; tuberculosis had declined sufficiently for vaccination to be stopped; As for measles and whooping cough, we live with irregular outbreaks,” he explains.
How can we explain their current resurgence?
As with other germs, scientists see this as a consequence of the cessation of barrier measures against the Covid pandemic, or a decline in collective immunity. But it is often insufficient vaccination coverage that is to blame.
The MMR vaccine (measles-mumps-rubella) in particular had been the victim of strong mistrust among parents due to fake news attributing cases of autism to it. Cases had increased so much in the 2000s that this vaccination went from recommended to mandatory for all infants in 2018, in an attempt to stem the phenomenon.
But “there are cases of measles in adults and adolescents among those who have not been vaccinated or have been poorly vaccinated (one injection instead of the two that are mandatory),” Mikael Askil Guedj points out.
For tuberculosis, which mainly affects people in very precarious situations, “there is a vaccine, BCG, which is no longer available anywhere in pharmacies.” And which, moreover, “does not protect very well,” he adds.
Regarding whooping cough, it would be necessary to “revaccinate in adulthood, particularly pregnant women” to protect future babies, because “the current vaccine does not protect against infection for life”, stresses Philippe Sansonetti.
As for syphilis, its return can be explained by the reduced use of condoms, since antiretrovirals have reduced the fear of AIDS.
“Many people carry it without knowing it, and continue to spread syphilis because the first symptoms are quite discreet or poorly identified,” adds Dr. Guedj.
Recommendations for getting rid of it
“Some countries have a more solid vaccination policy than France,” notes Philippe Sansonetti, who expects a lot from the future digital vaccination health record. “Today, there are holes and vagueness in the actual vaccination coverage” of adults, he notes. Without necessarily advocating compulsory vaccination for all, as is the case in pediatrics, the researcher questions the implementation of a better vaccination policy among adolescents and adults.
