A boom in streptococcal cases especially in younger children, affected much more than in the past, probably due to an immune debt linked to the protections used during the Covid-19 pandemic. This, at least, is the thesis supported by experts in a study conducted at the Catholic University – IRCSS Fondazione Policlinico Gemelli and published in the scientific journal “Lancet Microbe”, with particular reference to 2023.
The M1 immunotype
The streptococcus bacterium, therefore, seems to have raised its head again just after the end of the pandemic, particularly affecting children, forced to bed with high fever and swollen tonsils and with pharmacies stormed in search of diagnostic tests, so to record an incidence similar to the levels of the pre-pandemic period. In particular, in the series examined with a focus on 2023, 13-16% of all the samples examined tested positive for streptococcus. The experts underlined that the M1 immunotype circulated the most, the one considered the most serious and virulent.
Over 1,800 samples examined
The study, based on data collected between 2018 and 2023, focused in particular on the incidence of Streptococcus pyogenes (GAS) infection, through the pediatric emergency room observatory, directed by Dr. Antonio Chiaretti. In total, over 1,800 samples from throat-tonsillar swabs of children who arrived at the facility with flu symptoms were analyzed. “Between 2020 and 2022 we observed a significant reduction in streptococcal infections, both in terms of the quantity of samples received (due to reduced access) and a significant percentage reduction in positives”, commented Maurizio Sanguinetti, full professor of Microbiology at the Cattolica, director of the Department of Laboratory and Infectious Sciences, coordinator of his own study research together with Chiaretti “Non-pharmacological protection measures, such as the mask in those years, reduced contact with the microorganism and infection”. With the bacterium therefore being able to strike with greater intensity, especially among the youngest. “The suspicion is that the children, having been significantly protected during Covid, have not developed the normal, partially protective immunity against the infection”, continued Sanguinetti. “Contact with microorganisms is essential for ‘training’ the immune system to respond to infections. The hypothesis is therefore that the reduced contact with this microorganism has caused an ‘immunological debt’ in younger children, preventing them from developing protection, even partial and this has led to an increase in cases”, the expert further explained.
The swabs
One fact, above all, must also be underlined based on the study. “If a child is highly symptomatic, with high fever, enlarged and inflamed tonsils, it is advisable not to rely only on the do-it-yourself rapid test purchased at the pharmacy,” the researchers note. Rather, they say, it is preferable “a throat-tonsillar swab carried out in the laboratory, followed by a culture test” which allows the microorganism to be characterized, “with both diagnostic and epidemiological implications to evaluate the possible circulation of hyper-virulent strains”.
