Status: 11/25/2022 10:41 am
Numerous children’s hospitals are currently reporting an unusually large number of respiratory diseases. Have the pandemic measures weakened the immune system? Or does a corona infection damage the defense against other viruses?
A similar picture emerges everywhere in Germany, says Robin Kobbe. He is a pediatrician and researches infections in children at the University Hospital Eppendorf (UKE) and the Bernhard Nocht Institute in Hamburg. In the emergency rooms of some hospitals, infections are increasing again after a slight dip during the autumn holidays. “Even here in Hamburg, in the emergency room and also in the practices, respiratory diseases are quite common and the rescue center is full.”
Established by the University of Dresden and the German Society for Pediatric Infectious Diseases nationwide recording system for respiratory infections in children striking: Most of the children who come to the hospital because of this are infected with the so-called human respiratory syncytial virus, or RSV for short. This is also reported by Reinhard Berner, Director of the Dresden Children’s Clinic. RSV is a common virus that also infects adults. In them, the infection usually runs like a mild cold. However, younger children in particular have narrower airways, which means that bronchitis can develop more quickly and the infection can be particularly severe.
Training effect for the immune system
The fact that so many children are being affected is also due to the precautionary measures taken during the corona pandemic, says pediatrician Kobbe. He speaks of an “immunological gap”: Because the immune system of many people has worn a mask in the last two or three years and social distancing has seen fewer pathogens, it has not been trained, not through mild or asymptomatic infections “immunologically in the bar”. been held.
An explanation that is currently being hotly debated among parents on social networks – and sometimes with an ideologically motivated aftertaste. The measures, according to some, would have left an “immune debt” in young people, i.e. lasting damage to the immune system. Now other viruses could strike more violently. However: Infections are “not a must have for our immune system,” tweeted the virologist Isabella Eckerle ironically. “There is no ‘infection account’ that you have to work through so that you end up with zero at the end of the year.”
Shifted seasonality
Friedrich Reichert, senior physician in the pediatric interdisciplinary emergency room at the Stuttgart Clinic, says: “The immune system works great, even after the measures – there is no evidence that the absence of infections would weaken the immune system in any way.” So the “training effect” isn’t really necessary, but it’s there nonetheless.
Because what Kobbe is talking about is definitely a consequence of the measures, but only in the form of a shift in seasonality. Last year, the seasonal wave of infections with RSV started earlier, and it had a particularly high R value, as Reichert emphasizes. That means there were more people who were susceptible to the virus. On the one hand, because even with well-known respiratory diseases, immunity decreases after a while after the infection has been overcome. This means that if the last, possibly unnoticed infection was too long ago, it is easier to get infected again.
Significance of age factor unclear
In addition: Due to the pandemic measures, several infection years in children have failed. 90 percent of children usually get an RSV infection within the first two years of life, 50 percent even twice. But now many of them only have their first encounter with the virus in kindergarten. These first infections are often particularly severe, later infections become milder. And some five-year-olds today have not yet had a second or third infection with the respiratory pathogen as a result of the pandemic. “It’s just that this booster, if you want to call it that, didn’t materialize for this age group,” explains the Dresden pediatrician Berner.
The doctors cannot say whether there could be an advantage or disadvantage if initial infections occur later, purely in terms of age. The risk of a severe course is greatest under six months – on the other hand asthma can be a consequence in young children. “Weighing the whole thing up against each other would not really be scientifically sound,” says Reichert. The shift is therefore taking place at the population level and in principle has no medical significance for the individual child.
Role of the corona virus unclear
But the debate about the consequences of the pandemic for children also has an “opposite position”: The virus itself could have left its mark on the immune system, so the theory goes, even in those who – like most children – had a very mild course and none Have developed post Covid symptoms. Some pediatricians express this assumption, because it is well known and well documented from other viruses: Measles, for example, has long-term effects on T and B cellsthe immune protection against other pathogens is becoming weaker: who a Has gone through a measles infection often has to struggle with secondary diseases for a long time.
After an influenza, it is often bacterial pathogens that have it easier, explains children’s infectiologist Reichert: “Staphylococci, for example.” This has to do with a malfunction in the granulocytes, which make up most of the white blood cells. After Covid, however, Reichert has not been able to make this observation in everyday clinical practice: “The primary change in the blood count in the first few weeks looks like with other viruses”. There are laboratory studies that show influences even weeks after infection. However, it has not yet been possible to prove whether this actually leads to more other infections in real life. The pediatricians Kobbe and Berner also consider such an effect to be unlikely. It should also be difficult to research this seriously, because it is almost impossible to form a control group that has not yet had a corona infection.
Fear of overloading the children’s hospitals
In fact, the perceived reality could also be deceptive, and the RSV wave is not particularly high this year: The Stuttgart doctor Reichert sees a kind of normal situation for this time of year again, last year it was different. The wave looks “as usual”, which was also shown by data from Great Britain. Berner, however, believes that the cases will increase sharply in the coming weeks. Noisy The Robert Koch Institute keeps the RSV wave going, especially among small children.
Pediatricians are currently concerned about another virus in particular: the influenza pathogen. Because normally the “real flu” only plays a role later in the season, often only after the turn of the year. But the number of cases is already increasing, emphasizes Reichert: “This year, both RSV and influenza started at the same time.” If the flu wave is high, there will be acute supply problems. The influenza pathogen also brings many children to the hospital in heavy waves, and children’s hospitals are structurally undersupplied even in normal times compared to adult medicine. In the USA there are already warnings of a “tripledemic”, i.e. the triple epidemic caused by RSV, influenza and Covid in children.
Also vaccinate children against influenza
Berner and Kobbe therefore recommend looking after sick children at home and observing hygiene measures – such as washing your hands, sneezing into the crook of your arm and wearing a mask if you have cold symptoms to protect vulnerable people. Otherwise it could be like in Switzerland in the past few weeks: “It was the case there that the children were flown from Zurich to Lausanne because there were simply no more ventilation places,” says Berner.
Many paediatricians therefore recommend having school and kindergarten children vaccinated against influenza. Several EU countries such as Finland, Slovakia or Great Britain are now also using it vaccination of children of different age groups.
A corresponding STIKO recommendation has also been expected in Germany for a long time – apparently the pandemic got in the way. After all, the vaccine has been around for a long time and is also approved for children. However, it is not yet possible to actively vaccinate against RSV. But the pharmaceutical company Pfizer recently published a press release that gives hope: According to this, an RSV vaccine for pregnant women has been successfully tested, which also protects newborn children. Too late for this wave – but maybe a lever for next fall.