A British study suggests that Bangladeshi, Pakistani, Muslim, and Sikh groups tested positive for COVID-19 at higher rates than their White and Christian counterparts during surges driven by the Alpha and Delta variants.
In the observational study, published yesterday in BMJ Medicine, a team led by Office for National Statistics researchers examined COVID-19 rates among more than 39 million people aged 10 years and older in England from September 1, 2020, to May 22, 2021 (Alpha) or May 23 to December 10, 2021 (Delta). Average age was 47 years, and 82% were White.
Changing risk patterns
A total of 14.8% of the study population tested positive for COVID-19 during the study. During the Alpha wave, the fully adjusted relative risks of a positive test were highest among Bangladeshi and Pakistani ethnic groups (rate ratios [RRs] vs the White British group, 1.75 and 1.69, respectively).
Relative to the Christian group, the fully adjusted RRs for COVID-19 among Muslim and Sikh religious groups were 1.51 and 1.64, respectively. Other risk factors for a positive test included social deprivation, disadvantaged socioeconomic status, residence in a nursing home, and low English language proficiency.
The disparities among groups varied over time, with an increased relative risk of positivity among Christian, White British, socioeconomically advantaged, and nondisabled people during the Delta wave.
“Changes in the rate ratios observed in wave three compared with wave two could also be due to changes in testing behaviours in response to rollout of vaccination, changes in the perceived risk of infection or reinfection, and policy changes related to isolation periods and compensation after testing positive for SARS-CoV-2,” they wrote.
In a related editorial, Felix Chilunga, PhD, and Charles Agyemang, PhD, both of Amsterdam University Medical Centres, called for identification of the reasons behind the decline in risk among disadvantaged populations during the Delta wave. “Answers to these questions might help policymakers in the United Kingdom with the necessary tools to institute relevant public health interventions,” they wrote.