Children may have the same virus load as adults, but their risk of infection could be lower. Researchers advise caution when opening school.
Experience to date suggests that children are infected with the novel coronavirus just as often as adults , but are less likely to contract the lung disease Covid-19 caused by Sars-Cov-2. However, it has so far been unclear how infectious children are when they have been infected with the coronavirus.
A study by the Berlin Charité , published on Wednesday evening, shows that infected children probably have the same amount of viruses in their throats as adults. This finding suggests that they could be as contagious as adults. The study is in the preprint stage, so it has not yet been reviewed by independent scientists and published in a journal.
Charité chief virologist Christian Drosten, who was also involved in the study, published a graphic on Twitter that shows the viral load of different age groups, from kindergarten children to older people. "No significant difference between children and adults," Drosten wrote of the viral load.
This realization is likely to rekindle the daycare and school opening debate. Because if children are infected with the corona virus but show no symptoms, they could spread the virus unnoticed.
Christian Drosten is also spreading a new study on Twitter that shows that children could have a significantly lower risk of infection in adults. Drosten described this study as an "important counterpart" to the data on viral load collected by the Charité.
In this study, which was published in the journal "Science", scientists evaluated contact surveys from Wuhan and Shanghai and contact tracing data from the Chinese province of Hunan and used them to create a model. The researchers analyzed a total of 1,245 contacts reported by 636 study participants from Wuhan and 1,296 contacts from 557 participants in Shanghai.
"We found that the susceptibility of SARS-CoV-2 infections increases with age," write the scientists. Young people between the ages of 0 and 14 have a lower risk of infection than people between 15 and 64 years. The risk is highest for people over 65. The researchers from China, Italy and the USA came to the conclusion, among other things, that school closures alone cannot regulate a Covid 19 outbreak, but can slow it down significantly.
Researchers warn of unrestricted opening of daycare and school
For the investigation of the Charité, the virus amounts of a total of 3712 infected were compared on the basis of PCR tests carried out by the Charité. The research group of the Charité wrote in the study: “We warn against an unrestricted reopening of schools and kindergartens in the current situation. Children could be as infectious as adults. ”The tests were carried out in Berlin laboratories from January 2020 to April 26.
Of these, 37 were children of kindergarten age, 16 elementary school students and 74 adolescents who go to secondary schools. A total of 127 children were examined. That doesn't seem like much - according to Berlin scientists, only 1065 children tested positive worldwide.
The study found no statistical evidence that children have different viral loads than adults. In the current situation, in which a large part of the population is not immune and the infection rate has to be kept low, caution must be exercised.
The research situation remains confusing
The scientists also list the counter-arguments: children without symptoms would not cough, and they also exhale less air than adults. This would speak for a lower risk of infection from children. On the other hand, children are more physically active and have closer social contacts, which in turn speaks for a greater risk of infection.
It was necessary to collect more statistical data on the viral load of children from laboratories and to independently review the data already collected. Based on their results, the researchers advise treating children as potentially infectious as adults.
Both studies together show that children are less likely to contract the coronavirus than adults. If they are infected, however, they are probably just as contagious to others. In conclusion, these results are not, however, other studies say otherwise about the risk of infection in children. The research situation on the topic remains confusing.
Further examinations are to come in the coming weeks, including from four university hospitals in Baden-Württemberg. They are investigating how the infection of children and their parents with the virus differs.
Decision on schools and day-care centers postponed
In a study that is exclusively available to the Tagesspiegel, scientists used modeling to calculate how school openings could affect Berlin. The result: the openings could lead to a drastic increase in infections. The modeling was carried out by the international research group Mocos (Modeling Coronavirus Spread).
On Thursday, Chancellor Angela Merkel (CDU) consulted with the Prime Minister on further easing of the corona measures. The decision on schools and daycare centers was postponed until May 6.
Federal Education Minister Anja Karliczek had already made it clear in advance that she expects restrictions on the school system until the next school year. "The exceptional situation will continue well into the next school year," the CDU politician told the newspapers of the Funke media group.
"Only when large population groups are vaccinated will we return to the usual classes," said Karliczek. Until then, there will be a mix of classroom instruction and digital instruction.