Significant ethnic, religious, and social differences in the risk of testing positive for SARS-CoV-2 were identified during the height of the COVID-19 pandemic in a study for the open access journal, BMJ Medicine.
Researchers from the Office for National Statistics and the London School of Hygiene and Tropical Medicine, and colleagues, found that inequalities among the groups in England varied over time.
During the second wave, the risks were highest for Bangladeshi and Pakistani ethnic groups, compared with those of White British ethnicity, whilst Muslim and Sikh religious groups and people from deprived areas and of low socioeconomic status were also at particular risk.
However, in the third wave, the risk of testing positive for SARS-CoV-2 was highest for people of White British ethnicity, Christians, those with no underlying conditions or disabilities, and those who were relatively affluent.
Previous investigations and observations have highlighted that rates of COVID-related hospital admissions and mortality disproportionately affected older people, those with pre-existing health conditions or disabilities, ethnic minorities, some religious groups, care home residents, and people from low socioeconomic backgrounds. However, less is known about sociodemographic inequalities in infection rates.
Population Data Linked with Census Returns and Test results
To try to plug this gap in knowledge, the researchers used national population-linked health data, death registrations, and SARS-CoV-2 test result figures for just over 39 million people who were included in the 2011 census, registered with the NHS, and still alive on 1 September 2020. Positive test results from 1 September 2020 to 22 May 2021 were classified as occurring during the second wave of the pandemic, and those from 23 May 2021 to 10 December 2021 as occurring in the third wave.
The average age of the participants was 47, and just over half were female. Most (81.7%) identified as White British, 4.8% as White Other, 2.8% as Black African or Black Caribbean, 2.7% as Indian, 2.2% as Pakistani, and 0.8% as Bangladeshi. For religious affiliation, 59.5% identified as Christian, 25.5% as having no religion, and 5% as Muslim.
During the study period, 5.8 million (14.8% of the study population) had tested positive for SARS-CoV-2.
Results for the Second and Third COVID Waves
In the second wave, the fully adjusted relative risks of having a positive test were highest for the Bangladeshi and Pakistani ethnic groups compared with the White British group, with rate ratios of 1.75 (95% CI 1.73 to 1.77) and 1.69 (95% CI 1.68 to 1.70), respectively. Muslim and Sikh religious groups had fully adjusted rate ratios of 1.51 (95% CI 1.50 to 1.51) and 1.64 (95% CI 1.63 to 1.66), respectively, compared with the Christian group.
Greater area deprivation, disadvantaged socioeconomic position, living in a care home, and low English language proficiency were also associated with higher relative risk of having a positive test.
However, during the third wave, being Christian, White British, without a disability, and from a more advantaged socioeconomic position were associated with increased relative risk of testing positive, the study found.
The authors cautioned that due to the observational nature of their investigation they were unlikely to establish cause and effect. Furthermore, SARS-CoV-2 test data did not represent the true extent of infections because it tended to include more people with symptoms of infection than those who were asymptomatic. Also, adherence to testing has been shown to be lower among men and boys, younger people, and those with lower socioeconomic status, they pointed out.
The researchers concluded that while case rates "were found to vary considerably across different sociodemographic groups, particularly ethnicity and religion", further studies were needed "to understand why these inequalities exist and how they can best be addressed through policy interventions". The authors stressed that continued surveillance was necessary "to ensure that changes in the patterns of infection are identified early to inform public health interventions".
The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors. KK chairs the Ethnicity Subgroup of the UK Scientific Advisory Group for Emergencies (SAGE), and is a member of SAGE; ASW's institution received grants from the Department of Health and Social Care and the National Institutes of Health Research; RA received grants from New York University Abu Dhabi and Upjohn.