- Frequent infections of children with seasonal coronaviruses (colds, bronchitis) do not protect them from Covid-19.
- The results of this French study, pre-published on MedRxiv on June 30, 2020, had a strong media impact.
Children make mildly symptomatic forms of Covid-19 that often go unnoticed. They more rarely develop severe damage, similar to Kawasaki disease. This population is also sensitive to seasonal coronaviruses, responsible each winter for colds and repeated bronchitis.
In a new French study, researchers from the Pasteur Institute, Inserm, the AP-HP and the University of Paris demonstrate that the frequent infections of children with seasonal coronaviruses neither protect them nor the infection by the SARS-CoV-2 virus, responsible for Covid-19, or the serious forms related to Kawasaki disease. The results have been pre-published on MedRxiv, June 30, 2020.
No significant protection against infection
“Infection with seasonal coronaviruses does not provide significant protection against infection with SARS-CoV-2 virus and other associated diseases such as Kawasaki disease-like syndrome, comments Marc Eloit, co-author of the study and head of the Pathogen Discovery Laboratory at the Institut Pasteur. If the Covid-19 virus behaves like seasonal coronaviruses, this observation questions the ability of the population to reach a level of immunity sufficient to prevent the regular recurrence of the disease “, he specifies.
From 1is March to 1is June 2020, his team conducted a study in 7 hospitals in Paris and the immediate area, with 775 children, 36 of whom had a syndrome related to Kawasaki disease. The scientists wanted to determine the frequency, type and concentration of antibodies produced by children in response to infection and their ability to neutralize the SARS-CoV-2 virus.
Conclusion: the prevalence rate of the SARS-CoV-2 virus in patients with no (or few) symptoms was on average 11.7% of the study population. More than half (69.4%) of these children had never had symptoms suggestive of infection. Neutralizing antibodies were found in 56% of children with HIV. More than two-thirds of children with Kawasaki-like syndrome were HIV-positive for SARS-CoV-2.
“The presence and the rate of antibodies against the four seasonal coronaviruses, found in 67-100% of children depending on the virus, were comparable between HIV-negative children and children HIV-positive for Covid-19 virus, which he these are patients with Kawasaki disease-like syndrome or those who have had a symptomatic form (or little) “, concludes the Institut Pasteur.
Since the onset of the disease in late December in China, the coronavirus has killed more than 530,000 people worldwide, according to the latest AFP report.. Over 11 million cases of infection have been diagnosed in 196 countries and territories.