(A) Professor Cowling, epidemiologist and biostatistician:
The move to relax public health measures in Hong Kong means masks should no longer be mandatory while exercising outdoors, especially when it comes to hiking in country parks, according to an epidemiologist who has often publicly disagreed with government policy.
Professor Ben Cowling, head of the division of epidemiology and biostatistics at the University of Hong Kong, said considering the green spaces in the city as being “high risk” was “inconceivable”. He rated country parks as being at the “lowest of low-risk settings”.
(B) Dr Leung, respiratory expert:
Respiratory expert Dr Leung Chi-chiu said he considered country parks to be more dangerous to residents overall than people gathered in restaurants.
“Even if you want to meet your friends [at a restaurant instead], it is still a table of two,” Leung said. “You might be posing more of a risk to your friend, but you are posing less of a risk to hundreds of passers-by. From a public health perspective, you are not increasing the risk. We must proceed with an abundance of caution.”
Who to believe?
Options:
1. Believe neither or both. Though I’m not sure that’s possible unless you’re very good at Doublethink.
2. Believe the one who fits your priors. If you’re a safety-at- any-cost person, a “one death is too many” person, then go with Dr Leung. If you’re a risk balancer, or one who follows the issue closely and follows the actual Science then you’d go with professor Cowlimg.
3. You might do a bit more digging around and find that the Chinese said early on (March 2020) that this was not an “outdoor virus” , and that there is no actual real-life data to suggest outdoors is dangerous for catching Covid, even the Omicron variant.
4. You could use common sense: which one of these views sounds more commonsensical? You could back this up by taking your CO2 meter outdoors and indoors, and finding the readings indoors are around 1,000 (=high) and only 400 outside. This means any viral particles are less concentrated outdoors than indoors. Science!
5. Consider the expertise of each. Professor Cowling in epidemiology, the study of how diseases spread. And Dr Leung, in respiratory diseases, which means he knows how to treat your pneumonia, not necessarily how it’s spread. Does his statement about “you are posing less of a risk to passers-by” in a restaurant even make sense? Well, no, not really. And not by the evidence of your CO2 meter either.
So, I go with the views of professor Cowling.
Also: this is an example of how “the science” and “experts” can come to diametrically opposed conclusions about an issue, even two years into the pandemic.
We ought not, any of us, expert or not, think we have the answers and revile someone with a view different from yours. What goes around often does come around.
