SARS-CoV-2 antibody prevalence and determinants of six ethnic groups living in Amsterdam, the Netherlands: a population-based cross-sectional study, June-October 2020

Abstract

Background Ethnic minorities have higher rates of SARS-CoV-2 diagnoses, but little is known about ethnic differences in past exposure. We aimed to determine whether prevalence and determinants of SARS-CoV-2 exposure varied between six ethnic groups in Amsterdam, the Netherlands. Methods Participants aged 25-79 years enrolled in a population-based prospective cohort were randomly selected within ethnic groups and invited to test for SARS-CoV-2-specific antibodies and answer COVID-19 related questions. We estimated prevalence and determinants of SARS-CoV-2 exposure within ethnic groups using survey-weighted logistic regression adjusting for age, sex and calendar time. Results Between June 24-October 9, 2020, we included 2497 participants. Adjusted SARS-CoV-2 seroprevalence was comparable between ethnic-Dutch (25/498; 5.5%, 95%CI=3.2-7.9), South-Asian Surinamese (22/451; 4.8%, 95%CI=2.1-7.5), African Surinamese (22/400; 8.2%, 95%CI=3.0-13.4), Turkish (30/408; 7.8%, 95%CI=4.3-11.2) and Moroccan (32/391; 7.0%, 95%CI=4.0-9.9) participants, but higher among Ghanaians (95/327; 26.5%, 95%CI=18.7-34.4). 57.1% of SARS-CoV-2-positive participants did not suspect or were unsure of being infected, which was lowest in African Surinamese (18.2%) and highest in Ghanaians (90.5%). Determinants of SARS-CoV-2 exposure varied across ethnic groups, while the most common determinant was having a household member suspected of infection. In Ghanaians, seropositivity was associated with older age, larger household sizes, living with small children, leaving home to work and attending religious services. Conclusions No remarkable differences in SARS-CoV-2 seroprevalence were observed between the largest ethnic groups in Amsterdam after the first wave of infections. The higher infection seroprevalence observed among Ghanaians, which passed mostly unnoticed, warrants wider prevention efforts and opportunities for non-symptom-based testing.

Evolution of COVID-19 symptoms during the first 9 months after illness onset

“…Survival bias among the retrospectively-enrolled hospitalised participants may have caused an underestimation of time to complete recovery in those with severe/critical disease, although results were comparable when restricting our analyses to prospectively identified participants. Questionnaires in languages other than Dutch and English were not offered, therefore individuals with a migration background, who have been disproportionally affected by COVID-19, also in Amsterdam[25, 26], were underrepresented in this cohort. Furthermore, misclassification bias may have resulted from using ICU admission as a proxy for critical disease; suitability for ICU admission is also judged by the patient’s chance of survival; indeed, those with critical disease tended to be younger and have a lower BMI than those in the severe group.…”

Contextual factors that shape uptake of COVID-19 preventive measures by persons of Ghanaian and Eritrean origin in the Netherlands: A focus group study

“…In high-income countries, migrant and minority ethnic populations have been shown to be at increased risk of confirmed SARS-CoV-2 infection 4 , 5 , 6 . In the Netherlands, higher infection seroprevalence was observed among persons of Ghanaian origin after the first wave of infections [7] . In line with the crucial role of human behaviour, previous studies indeed provide evidence to suggest lower uptake of preventive measures in migrant and minority ethnic populations [ 8 , 9 ].…”

“…Research on smaller migrant and minority ethnic populations and in other country settings is scarce. The research project ‘Ethnicity and COVID-19: Epidemiology and control measures’ initiated at the request of The Netherlands Organization for Health Research and Development aims to establish a comprehensive view on COVID-19 amongst migrant and minority ethnic populations in The Netherlands and formulate policy recommendations [7] . Specifically, this qualitative study intended to gain an understanding of smaller, albeit substantial, migrant and minority ethnic populations with varying migration backgrounds, migration motives and length of stay in the Netherlands.…”

Ethnic disparities in incident SARS-CoV-2 infections became wider during the second wave of SARS-CoV-2 in Amsterdam, the Netherlands: a population-based longitudinal study

“…Participant characteristics have been described in detail previously. 12 S1. The age and sex distribution of participants who returned by March 31, 2021 were comparable to participants who did not; however, participants who did not return were more likely to be first generation migrants, not be employed, and have a lower educational and occupational level, difficulties with the Dutch language, lower health literacy, and SARS-CoV-2 antibodies at the first visit (Table 1).…”

“…A large population-based study conducted after the first wave of the SARS-CoV-2 epidemic found that only individuals of Ghanaian origin were at higher risk of past exposure to SARS-CoV-2, whereas individuals of South-Asian Surinamese, African Surinamese, Turkish, or Moroccan origin had a similar risk compared with individuals of Dutch origin. 12 Given the potential for ethnic differences during the subsequent waves of the SARS-CoV-2 epidemic and the limitations from previous studies, we aimed to investigate whether SARS-CoV-2 incidence differed between individuals of South-Asian Surinamese, African Surinamese, Ghanaian, Turkish, Moroccan and Dutch origin living in Amsterdam, specifically during the first and second waves of the Dutch SARS-CoV-2 epidemic. Using longitudinal seroprevalence data nested within the large, population-based cohort study HEalthy Life in an Urban Setting (HELIUS), 13 we compared the SARS-CoV-2 incidence between ethnic groups and identified determinants of incident infection within ethnic groups in Amsterdam, the Netherlands.…”