The number of new infections with the corona virus has reached new record highs in Austria in the past few days, the situation is tense and once again the fear of a hard corona winter hangs like a sword of Damocles over the heads of business, tourism, trade, cultural companies and the entire public as well as private life. The measures to combat and contain the pandemic are now moving in quick succession: the Austria-wide 2-G rule came into force on Monday, the vaccination centers are experiencing a real run and without a vaccination or recovery certificate, PCR test and mask works so well like nothing more.
Rumors of a new lockdown also persist, as do reports of vaccination breakthroughs and that the masks weaken us more than they protect us. Now that life is shifting more and more into closed rooms, the risk of contamination from aerosols is again a big issue. In an interview with the Swiss, aerosol expert and risk researcher Michael Riediker explains how big and serious these suspended particles really are “Day indicator”.
Many health authorities have neglected the importance of aerosol transmission, mask requirements in indoor areas or air filter systems were often an issue in prevention discussions, but were rarely implemented in practice. Now, however, some authorities are adapting their recommendations and aerosols are – unfortunately in the truest sense of the word – on everyone’s lips again. Rightly so, as occupational hygiene and risk researcher Michael Riediker thinks. According to him, the risk of infection indoors is now many times higher than it was 12 months ago.
“A few minutes are enough for an infection via aerosols in a smaller room,” says Riediker, who cites the more aggressive mutations of the virus as the reason for the increased risk of infection. “At Delta, a lot more people have greatly increased viral loads. As a result, almost every third infected person is a high emitter, ie someone who can infect other people in a small room very quickly if you don’t take precautionary measures, ”said the expert.
Around a year ago, most infected people with an average or low viral load were very unlikely to be infected by aerosols, even with frequent coughing. This looks completely different: Because the delta variant, which is much more contagious than its predecessor, statistically speaking, almost half of the infected people are infected via aerosols: “This much larger number of infected people, who release critical amounts of viruses as aerosols in my opinion also explains why Delta was able to spread so rapidly. that now around every thirtieth infected person is super-emissive, compared to one in a thousand for the wild-type virus of the first wave. Such a person is highly contagious through aerosols, ”said Riedeker.
This means: there are now 97 percent more super spreaders than a year ago and infection can happen much more easily: “A few minutes without a mask with such a person in a smaller room are enough for an infection, if they are singing or otherwise very loud . Even if this person stays calm, you can get infected in a small office without a mask within an hour, ”explains the expert. That is why Riedeker advises even if you are vaccinated to be more careful indoors and advises to wear an FFP2 or FFP3 mask. Outside, the risk of infection is still a lot lower, but it is important to keep your distance here as well.
