Are infected hamsters really so much more dangerous?

I’m reading a preprint by Hawks and coworkers. They used controlled lab experiments with hamsters to show that when infected the hamsters breath out infectious SARS-CoV-2 — the virus that causes COVID-19. This is in small (less than 8 micrometres in diameter) droplets, that can travel several metres across a room. This result is not a surprise but it is good to show this. Surprisingly, given how contagious COVID-19 is, showing definitively that you have infectious virus is technically very challenging, so it is good to see it being done. It confirms that we can catch COVID-19 from an infected person that may be across a room from us, and so social distancing by a metre or two may reduce the risk, but does not eliminate it.

But what struck me about this paper is not this, expected but important finding, but the fact that the experiments were done in special Biosafety Level 3 (BSL3) laboratories. To give some background: lab studies involving dangerous infectious agents such as TB, SARS-CoV-2, anthrax, etc are not done in just any old biology labs but in special dedicated labs designed to protect users and others from these dangerous bacteria and viruses. That this is required is, I think, a very good thing.

And Biosafety Level 3 is a lot, see the HSE guidance. Requirements include specific ventilation, special benches and floors, PPE, dedicated training … the works. It is good to be safe, and the requirements are thorough.

So, let’s recap: If, say a university student or academic wants to enter a room with a hamster that may be infected with COVID-19, they are required to have special training, the room must have high-performance ventilation, and much much more. And this is regulated by the government. However, the same government currently requires almost nothing before a university student or academic can enter a room with a hundred or two hundred students — for example for a lecture. The most recent (as of 12th August 2021) ONS figures are that about 2.5 % of teens/young-adults (12 to 24 years old) are currently infected with COVID-19. That is an average of 5 per 200. Now some of these will have symptoms and will be self-isolating, but a significant number of those infected show no symptoms, and so may be unaware they are infected. So the chances of a group of 200 young adults containing at least one infected but unaware individual, is high.

This dramatic difference between the ways risks from infected hamsters and from infected humans are treated, seems very odd to me. Universities are currently struggling with how to offer or whether to offer face-to-face lectures, and are on the receiving end of some harsh headlines. I think these are unfair. It is difficult for university staff to treat SARS-CoV-2 as a a dangerous threat in an lab, but as nothing to worry about in a lecture theatre.