Pandemic: Corona virus: Is there a “killer variant” in the fall?

After Federal Health Minister Karl Lauterbach (SPD) warned of a possible “killer variant” of the corona virus in autumn, experts emphasized the unpredictability of the development.

“No expert can currently say for sure which variant we will get in autumn,” said intensive care physician Stefan Kluge from the University Hospital Hamburg-Eppendorf of the Funke media group. “However, we should be prepared for the fact that another variant can occur that leads to a higher severity of the disease than is currently the case with the omicron variant.”

Lauterbach had spoken in the “Bild am Sonntag” of a possible “hard autumn” in view of the vaccination gap. “It’s entirely possible that we could get a highly contagious omicron variant that’s as deadly as Delta. That would be an absolute killer option.” The minister spoke of ever shorter intervals between dominant variants, which makes preparation more difficult. Various omicron subvariants are currently developing which are worrying for him.

Sublineages of omicron

Lauterbach is likely to allude to several sub-lines of Omikron that have recently come into focus. First of all: Up to now BA.2 has been predominant in Germany, previously it was BA.1. Recently, BA.4 and BA.5 also appeared, which the World Health Organization (WHO) as part of Omikron also classifies as worrying. According to WHO information, evidence came from South Africa and some European countries. Both sub-lines had different characteristics than other Omicron variants, it was said – but details are still open.

In addition, a possibly even more easily transferable omicron subvariant has been described in Great Britain – but much is also unclear about the subtype called XE. According to WHO information, it is a mixed variant of BA.1 and BA.2, a so-called recombinant. These can not only form from two subtypes, but also from different variants: for example from delta and omicron, which has also been observed and sometimes called deltakron. Recombinants can arise when a patient is infected with different Sars-CoV-2 pathogens at the same time.

How is the development of BA.4, BA.5 and XE in Germany? Open minded. In previous weekly reports, the Robert Koch Institute (RKI) does not go into subtypes so specifically.

Experts continue to urge vaccination

“We currently have a mortality rate of less than 0.1 percent at Omikron, comparable to the flu,” said intensive care physician Kluge of the Funke media group. Even if he warned to prepare for a possible worse variant: There are voices that consider it unlikely that the virus will become deadlier again in the future, especially for those who have been vaccinated. Among other things, experts are urging that as many people over the age of 60 as possible should be vaccinated in preparation for all cases.

The breadth of possibilities and the uncertainty show four scenarios that the British scientific advisory group SAGE presented for Great Britain in February: According to this, in the best-case scenario, Sars-CoV-2 could come back in autumn without significantly changed properties. In the worst case, however, another big wave with many severe courses is conceivable. Between the two scenarios, the group names one more optimistic and one more pessimistic – and emphasizes that other developments cannot be ruled out.

Omicron level can hardly be increased

The only thing that is fairly certain is that Corona will be with us for a long time, also in the form of new variants. How bad they get depends on a number of factors. The SAGE group sees growing importance in the issue of declining immunity and immune evasion – the ability of the virus to evade antibodies in the vaccinated and recovered. Previous waves were mainly driven by ever better transferrable variants. However, some researchers believe that the high level of omicron can hardly be increased.