Has Boris seen the Omicron data?

There was nothing but gloom about the Omicron variant at yesterday’s No. 10 press conference. But with reporters preoccupied with last year’s Christmas parties, no one thought to bring up a statement by Tedros Adhanom Ghebreyesus, the head of the WHO, who earlier told reporters that there is ‘some evidence that Omicron causes milder disease than Delta, but again it’s still too early to be definitive.’ 

You don’t want to make decisions before you have good evidence, but if it does turn out that Omicron is a milder disease, won’t the government’s efforts to suppress it with travel bans and restrictions be counter-productive? If Omicron makes people significantly less ill than Delta, it should be allowed to out-compete Delta.

So, what evidence do we have that Omicron may produce a less severe disease? Doctors in South Africa were surprised by the mildness of symptoms shown by some patients very soon after it was detected. Since then, the South African Medical Research Council has produced further evidence. In spite of a sharp rise in infections reported in hospitals over the past fortnight, relatively few are oxygen-dependent compared with previous waves of Covid. 

A snapshot of 42 patients on the Covid wards of two hospitals in Tshwane on 2 December revealed that only 13 were oxygen-dependent, and of these four required oxygen for conditions unrelated to Covid. The remaining nine had a diagnosis of Covid pneumonia. Of these, four were in ‘high care’ and only one in intensive care. 

Most patients with Covid were described as ‘incidental Covid admissions’, meaning that they were in there for another reason but had been diagnosed with Covid while they were there. 

Of the 42 patients, 38 were adults. Of these, six were vaccinated, 24 unvaccinated and in eight cases their status was unknown. Of the nine patients with Covid pneumonia, eight were unvaccinated. Only one patient who was fully-vaccinated was on oxygen — and in that case the reason for supplementary oxygen was COPD. In other words, not a single fully-vaccinated Covid patient in the Tshwane hospitals on 2 December had to be put on oxygen because of Omicron. The average length of hospital stay for a Covid patient in the past fortnight has been 2.8 days, while the average for the pandemic as a whole has been 8.5 days.

This is limited evidence and, given that the patients were relatively young, there is the possibility that Omicron has yet to spread among the elderly population of South Africa. Yet it seems a little odd to raise the spectre of Omicron being much more transmissible than previous variants — for which there is also limited evidence — without also mentioning that it may well turn out to be a good deal less deadly.