Is there a genetic element to the risk of being infected with Covid — and are some disadvantaged ethnic groups more vulnerable to the virus? This was once one of the most controversial questions about Covid — asked often during the first and second waves of the pandemic when it became apparent that infection and death rates were higher among some ethnic groups than others (a government report was published at the time). Among the factors discussed were the tendency of black and Asian Britons to work in exposed, public-facing roles such as in transport, their greater presence in crowded, inner-city districts and the greater prevalence of multi-generational households among some groups. Another factor was the vaccination gap, with ethnic minorities being far less likely to be jabbed.

Yet a new Office for National Statistics analysis comparing the second and third Covid waves shows something interesting: this time, white Britons were more likely to be infected. The data compares two periods: the ‘second wave’ (September 2020 to May last year) and the ‘third wave’ between (May to 10 December last year).

In the second wave, the highest infection rate was among those of Bangladeshi and Pakistani heritage — with infection rates of 382 and 374 per 100,000 person-weeks respectively. In the third wave, however, the group with the highest infection rate was white British, with a rate of 360. There was a similar (though less pronounced) switch among the black African and black Caribbean populations — who had higher infection rates relative to the white British population during the second wave but lower infection rates in the third wave. The exception was in Britain’s Chinese population, which had the lowest infection rate in both the second and third waves. The data does not cover the first wave, during the spring of 2020, before mass testing began. The Omicron variant was first detected in the UK near the end of November last year.

There is a similar switch in infection rates between the second and third waves when data is broken down by socio-economic group and by geographic location. In the second wave, the highest infection rates were detected among those in routine and semi-routine occupations; in the third wave it switched, with those in managerial occupations most likely to be infected. As regards geography, during the second wave people living in conurbations were most likely to be infected; during the third wave this switched to town and fringe locations.

It is not that the virus ‘discriminates’ based on ethnicity, as was sometimes claimed early in the pandemic: rather, the data seems to depict a virus gradually working its way through the population. It started among people living in crowded urban locations and working in manual, public-facing roles before spreading to groups who had been more sheltered from the virus early on. Groups who were more heavily affected during the second wave presumably had higher levels of acquired immunity. It’s possible (although we’re far from being able to say anything for sure) that this is a factor.

But it is interesting that the white British population went on to have the highest rate of infection during the third wave despite having higher vaccination rates than other ethnic groups. Around 68 per cent of the white British population have been boosted, twice the rate of those of black Caribbean heritage (34 per cent). The Pakistani, black African and Bangladeshi populations also had low rates of vaccination uptake.

There had been understandable concern about the low vaccination rates amongst ethnic minorities, and vaccine passports were — at one stage — seen as a tool that might address this. But with Omicron, as opposed to the first two waves, it does not seem that ethnic minorities were more susceptible to the virus.