Covid’s fifth wave shows us how to live with the coronavirus, masks or no masks

The new wave is mainly being driven by countries lifting pandemic restrictions as the more transmissible subvariant Omicron BA2 began to spread.

In the UK, the end of mask requirements on public transport and the need to self-isolate if infected has led to many people abandoning precautionary behavior and BA2 infections gaining momentum.

As of this week Britain has allowed five million elderly and more vulnerable residents for a fourth jab. Health Minister Sajid Javid has suggested that a fourth vaccine could be offered to those over 50 from the autumn. That may be reasonable, but as with previous boosters, any effect will likely be short-lived – we’ll see a three to four month reduction in cases rather than a fundamental change.

Data from Denmark and Sweden, the two countries where BA2 gained an early foothold, suggest that waning immunity is driving the rise in infections less than BA2’s superior ability to infect humans.

Denmark experienced an early, massive omicron wave. This arguably provided a high level of immunity to BA1 and BA2 and prevented its resurgence. But even Sweden, which had a smaller wave of BA2 infections, is currently not seeing a spike in infections. Both have similar vaccination protection. The curve of infection would look very different if we were to see declining immunity rather than the arrival of BA2.

Although hospitalizations due to Covid are increasing in the UK and other places where BA2 has spread rapidly, the rate of hospitalizations and ICU admissions per case remains low and there is no evidence to date that the BA2 subvariant leading to increased severity of the disease.

In the US, the picture is less clear. In the last two Covid waves, the course of US infections lagged behind that of Europe by a few weeks, so the same could happen this time as well. Currently, the percentage of BA2 omicron cases in the US is between 10 and 15 percent, the same level as in the UK in early February. As the subvariant multiplies, infections are likely to increase.

One factor in the US’s favor is that the BA1 omicron wave has likely infected a larger proportion of the US population than most European countries, so immunity to it could limit the duration of the BA2 wave, as well as its severity.

However, the US cannot afford to be too relaxed. Vaccination coverage is not as good as in most European countries. The more transmissible subvariant will also be better at finding groups of unvaccinated individuals, keeping rates of severe disease at higher levels in the US compared to Europe.

Congress just cut $15 billion in coronavirus funding. Fewer tests and fewer treatments could make it harder, especially for more vulnerable sections of the population.

Rising infections pose the greatest challenge for countries like China, which have been pursuing a zero-Covid policy. These highly restrictive regimens prevented infections from earlier variants and kept mortality rates low, but their vaccines were less effective against the more transmissible Omicron variant and its faster-spreading BA2 subvariant.

In New Zealand, strong immunization coverage is helping to manage the severity of the disease, with the number of deaths per million remaining at relatively low levels. That contrasts sharply with the picture in Hong Kong, where a rapid rise in infections is driving one of the highest death rates at nearly 40 per million.

The difference is vaccines. Mainly using the Chinese vaccine Sinovac, Hong Kong has only managed to get booster shots to 26.8 percent of its population. New Zealand, which used mostly mRNA vaccines, has boosted 50 percent of its population. China is in a very similar situation to Hong Kong: the zero-Covid policy resulted in low levels of popular immunity.

The current Covid wave should reassure us that vaccines and treatments remain our best defence. But it’s also a reminder that while we learn to live with Covid, we cannot ignore it. (©Bloomberg)

(This column does not necessarily represent the opinion of the editors or of Bloomberg LP and its owners.)

Therese Raphael is a columnist for Bloomberg Opinion. She was editor of the editorial page of the Wall Street Journal Europe. Sam Fazeli co-authored this article