Midsummer is history, and with the start of school last week – as in previous years – the question arises: What does this mean for CoV infections? One thing is sure: even during the endemic phase, surprising and problematic viral variants may emerge.
The number of infections is rising again, albeit at a low level. Still, the upward trend has continued for a few weeks now – this can be seen from the current data of the wastewater monitoring and the sequence analyses of AGES. The viral variation EG.5.1 (also known as Eris) is currently in charge of the infection outbreak in Austria and is responsible for around 40% of all coronaviruses found in wastewater.
In the sentinel system, the SARS-CoV-2 positive rate is currently 32%.
No detection of influenza or RSV
The number of total samples sent in a week remains at a low-level pic.twitter.com/Na1WfHG9Wu
- Judith Aberle (@AberleJudith) September 3, 2023
A slight digression on terminology: EG.5.1 is an XBB descendant whose designation became increasingly complicated due to the permanent branching of the Omikron family tree. Therefore, it was decided to go new ways with the abbreviation “EG.5”.
Vaccination should work well.
According to Monika Redlberger-Fritz of MedUni Vienna, the relationship between EG.5.1 and EG.5.1 is definitely “advantageous,” and the virologist assumes that the vaccines that will soon be available that have been adapted to XBB will also work well against EG.5.1.
Her specialist colleague Andreas Bergthaler, also from MedUni Vienna, essentially expected the current situation: “The virus will continue to mutate, there will be new variants. But we have also built up very good immunity over the last three and a half years. And because the immune system is very complex, even an immune escape variant will not completely escape our body’s defenses. That actually makes me optimistic.”
The Pirola variant raises questions.
One such immune escape variant has already appeared on the horizon. The pathogen BA.2.86 vulgo Pirola has already been detected on all continents. Denmark, Israel, Thailand, Switzerland, the USA and many others have already registered its genetic fingerprint, although it is entirely unclear where it originated.
That’s because much less sequencing is done worldwide now than during the pandemic, says molecular biologist Ulrich Elling of the Academy of Sciences. He suspects that the virus originated in the body of an immunocompromised patient, where it accumulated an astonishing number of mutations. These mainly affect the spike protein the virus uses to “crack” cells.
- Daniele Focosi, MD PhD MSc (@dfocosi) September 1, 2023
In this way, Pirola has moved so far away from currently circulating viruses in the broader Omicron family that the WHO is now prepared to assign a new Greek letter (Pi or Rho) should the virus become a “variant of concern.” This is not the case at present.
Infectivity probably reduced
Pirola does have the potential to partially hide from the immune system due to its unique genetic makeup. On the other hand, this is precisely why the pathogen will likely have difficulty infecting cells efficiently.
- Ulrich Elling (@EllingUlrich) August 31, 2023
In any case, new data suggests that Pirola is not particularly contagious. Which, in turn, might be an explanation for its leisurely reproduction so far. However, this finding will not last forever because further changes could increase the virus’s fitness – and possibly its dangerousness. It has, therefore, been placed under observation by the WHO.
- source: orf.at/picture: pixabay.com