tetano
Editor, Senior Moderator
BMC Infect Dis
. 2025 Sep 25;25(1):1126.
doi: 10.1186/s12879-025-11551-9. Seroprevalence of SARS-CoV-2 antibodies in Ethiopia: findings from the 2022 national population-based survey (second round)
Geremew Tasew[SUP] #[/SUP][SUP] 1 [/SUP], Saro Abdella[SUP] #[/SUP][SUP] 1 [/SUP], Birra Bejiga[SUP] #[/SUP][SUP] 2 [/SUP], Eshetu Ejeta[SUP] 1 [/SUP], Lehageru Gizachew[SUP] 3 [/SUP], Leuel Lisanwork[SUP] 3 [/SUP], Feyiso Bati[SUP] 1 [/SUP], Ebba Abate[SUP] 3 [/SUP], Legesse Negash[SUP] 1 [/SUP], Zelalem Bonger[SUP] 3 [/SUP], Joan Miquel[SUP] 4 [/SUP], Festo Mazuguni[SUP] 5 [/SUP], Zelalem Mekuria[SUP] 4 [/SUP], Kokou Nouwame Alinon[SUP] 5 [/SUP], Wang Shu-Hua[SUP] 4 [/SUP], Ahmed E Ogwell Ouma[SUP] 5 [/SUP], Hiwot Moges[SUP] 5 [/SUP], Wondwossen Gebreyes[SUP] 4 [/SUP], Getachew Tollera[SUP] 1 [/SUP], Masresha Tessema[SUP] 1 [/SUP], Desmond E Williams[SUP] 6 [/SUP]
Affiliations
Background: Assessing COVID-19 burden through clinical surveillance is suboptimal, as individuals with mild or no symptoms rarely seek care. Seroprevalence studies overcome this limitation by capturing both symptomatic and asymptomatic infections, providing accurate estimates of community transmission, immunity gaps, and epidemic progression. This is critical for informing public health strategies, especially in resource-limited settings like Ethiopia post-vaccine rollout.
Objective: To estimate the national seroprevalence of SARS-CoV-2 antibodies in Ethiopia after widespread vaccine deployments.
Methods: A population-based cross-sectional study was conducted using stratified three-stage cluster sampling across 11 regions (excluding Tigray). We enrolled 14,074 participants (99% response rate) adult population aged (≥ 15 years). Data on demographics, comorbidities, vaccination status, and preventive behaviours were collected via structured questionnaires. Serological testing used RightSign™ COVID-19 IgG/IgM Rapid Test Cassettes. The data were entered into Open Data Kit (ODK) Survey-weighted analyses in STATA 17 included summary statistics, bivariate analysis, and multivariate binary logistic regression (reporting Adjusted Odds Ratios, AOR).
Results: Among 14,074 participants (99% response rate; 58.9% female; mean age 35.3 years), the overall national seropositivity for SARS-CoV-2 antibodies was 48.0% (95% CI: 46.6-49.4%). IgG seroprevalence (45.1%) significantly exceeded IgM (1.2%), indicating predominantly past infections. Significant geographic variation existed, with Addis Ababa showing the highest seropositivity (68.1%; 95% CI: 65.7-70.5%) and Sidama (39.6%; 95% CI: 36.39-42.98%) and Gambella (40.5%; 95% CI: 37.01-44.02%) the lowest. Higher seropositivity was observed in females (50.1% vs. males 45.8%), urban residents (55.6% vs. rural 45.7%), and vaccinated individuals (59.1% vs. unvaccinated 37.2%). Multivariate analysis identified key predictors: vaccinated individuals had 2.64-fold higher odds (AOR = 2.64: 95% CI = 2.34-2.99; p < 0.001); urban residence increased odds by 41% (AOR = 1.41; 95% CI = 1.25-1.59; p < 0.001); diabetes (AOR = 1.87; 95% CI = 1.17-2.97; p = 0.009) and hypertension (AOR = 1.72; 95% CI = 1.23-2.41; p = 0.001) elevated risk; while smoking reduced odds by 24% (AOR = 0.76; 95% CI = 0.60-0.97; p = 0.028). Older age groups showed progressively higher odds (e.g., 55-64 years: AOR = 1.56; 95% CI = 1.19-2.06; p < 0.001 vs. 15-24 years) CONCLUSION: The study found Nearly half of Ethiopians had SARS-CoV-2 antibodies by mid-2022, with Significant disparities by regions, demographic groups, and vaccination status. Dominance of IgG antibodies (45.1%) over IgM (1.2%) indicates widespread prior infection. An identified rural immunity gap underscores the urgent need for targeted vaccination strategies among high-risk subgroups in underserved areas to advance toward herd immunity.
Keywords: Antibodies; COVID-19 vaccines; Ethiopia; IgG; IgM; SARS-CoV-2; Seroprevalence.
. 2025 Sep 25;25(1):1126.
doi: 10.1186/s12879-025-11551-9. Seroprevalence of SARS-CoV-2 antibodies in Ethiopia: findings from the 2022 national population-based survey (second round)
Geremew Tasew[SUP] #[/SUP][SUP] 1 [/SUP], Saro Abdella[SUP] #[/SUP][SUP] 1 [/SUP], Birra Bejiga[SUP] #[/SUP][SUP] 2 [/SUP], Eshetu Ejeta[SUP] 1 [/SUP], Lehageru Gizachew[SUP] 3 [/SUP], Leuel Lisanwork[SUP] 3 [/SUP], Feyiso Bati[SUP] 1 [/SUP], Ebba Abate[SUP] 3 [/SUP], Legesse Negash[SUP] 1 [/SUP], Zelalem Bonger[SUP] 3 [/SUP], Joan Miquel[SUP] 4 [/SUP], Festo Mazuguni[SUP] 5 [/SUP], Zelalem Mekuria[SUP] 4 [/SUP], Kokou Nouwame Alinon[SUP] 5 [/SUP], Wang Shu-Hua[SUP] 4 [/SUP], Ahmed E Ogwell Ouma[SUP] 5 [/SUP], Hiwot Moges[SUP] 5 [/SUP], Wondwossen Gebreyes[SUP] 4 [/SUP], Getachew Tollera[SUP] 1 [/SUP], Masresha Tessema[SUP] 1 [/SUP], Desmond E Williams[SUP] 6 [/SUP]
Affiliations
- PMID: 40999354
- PMCID: PMC12465790
- DOI: 10.1186/s12879-025-11551-9
Background: Assessing COVID-19 burden through clinical surveillance is suboptimal, as individuals with mild or no symptoms rarely seek care. Seroprevalence studies overcome this limitation by capturing both symptomatic and asymptomatic infections, providing accurate estimates of community transmission, immunity gaps, and epidemic progression. This is critical for informing public health strategies, especially in resource-limited settings like Ethiopia post-vaccine rollout.
Objective: To estimate the national seroprevalence of SARS-CoV-2 antibodies in Ethiopia after widespread vaccine deployments.
Methods: A population-based cross-sectional study was conducted using stratified three-stage cluster sampling across 11 regions (excluding Tigray). We enrolled 14,074 participants (99% response rate) adult population aged (≥ 15 years). Data on demographics, comorbidities, vaccination status, and preventive behaviours were collected via structured questionnaires. Serological testing used RightSign™ COVID-19 IgG/IgM Rapid Test Cassettes. The data were entered into Open Data Kit (ODK) Survey-weighted analyses in STATA 17 included summary statistics, bivariate analysis, and multivariate binary logistic regression (reporting Adjusted Odds Ratios, AOR).
Results: Among 14,074 participants (99% response rate; 58.9% female; mean age 35.3 years), the overall national seropositivity for SARS-CoV-2 antibodies was 48.0% (95% CI: 46.6-49.4%). IgG seroprevalence (45.1%) significantly exceeded IgM (1.2%), indicating predominantly past infections. Significant geographic variation existed, with Addis Ababa showing the highest seropositivity (68.1%; 95% CI: 65.7-70.5%) and Sidama (39.6%; 95% CI: 36.39-42.98%) and Gambella (40.5%; 95% CI: 37.01-44.02%) the lowest. Higher seropositivity was observed in females (50.1% vs. males 45.8%), urban residents (55.6% vs. rural 45.7%), and vaccinated individuals (59.1% vs. unvaccinated 37.2%). Multivariate analysis identified key predictors: vaccinated individuals had 2.64-fold higher odds (AOR = 2.64: 95% CI = 2.34-2.99; p < 0.001); urban residence increased odds by 41% (AOR = 1.41; 95% CI = 1.25-1.59; p < 0.001); diabetes (AOR = 1.87; 95% CI = 1.17-2.97; p = 0.009) and hypertension (AOR = 1.72; 95% CI = 1.23-2.41; p = 0.001) elevated risk; while smoking reduced odds by 24% (AOR = 0.76; 95% CI = 0.60-0.97; p = 0.028). Older age groups showed progressively higher odds (e.g., 55-64 years: AOR = 1.56; 95% CI = 1.19-2.06; p < 0.001 vs. 15-24 years) CONCLUSION: The study found Nearly half of Ethiopians had SARS-CoV-2 antibodies by mid-2022, with Significant disparities by regions, demographic groups, and vaccination status. Dominance of IgG antibodies (45.1%) over IgM (1.2%) indicates widespread prior infection. An identified rural immunity gap underscores the urgent need for targeted vaccination strategies among high-risk subgroups in underserved areas to advance toward herd immunity.
Keywords: Antibodies; COVID-19 vaccines; Ethiopia; IgG; IgM; SARS-CoV-2; Seroprevalence.