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Abstract
Introduction. Several studies show that COVID-19 vaccines prevent against severe illness, hospitalisation and reduce death rate. However, research on new infections in vaccinated people is limited. This present study aims to estimate the incidence of COVID-19 in vaccinated people in Congo. Methods. We have used data from the community study conducted between 2021 and 2023 in people vaccinated in Brazzaville and Pointe-Noire. Incidence curves were plotted using the Prentice estimator and compared with the Gray test. So, factors associated with infection were identified by using Cox regression. Results. Among the 4,185 participants, 66.7% were male, with a median age of 37 years; 94.5% were contacts, and 53.4% received the Johnson & Johnson vaccine. The overall COVID-19 incidence was 2.32%, increasing over time to 2.16%, 3.7%, 5.7%, to 12.9% at 6-, 12-, 24-, and 30-months post-vaccination, respectively. After adjustment, factors associated with infection include: being a healthcare worker (HR=2.52 [1.16–5.43], p=0.0019), having contact with a confirmed case (HR=15.5 [2.08–115.00], p=0.007) and age group of 45-64 years (HR=0.37 [0.17 – 0.85], p=0.019).Conclusion. This study shows an increasing incidence of COVID-19 in people vaccinated over time, suggesting a gradual decline of antibodies induced by vaccines. Therefore, the COVID-19 vaccination schedule for healthcare workers, contacts of COVID-19 patients and older people may need to be reassessed.
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References
- 1. Organisation mondiale de la Santé. COVID-19 epidemiological update – 6 November 2024 [Internet]. 2024 [cité 13 déc 2024]. Disponible sur: https://www.who.int/publications/m/item/covid-19-epidemiological-update-edition-173
- 2. Feraoun Y, Maisonnasse P, Grand RL, Beignon AS. COVID-19, des vaccins à la vitesse de l’éclair. Med Sci (Paris). 1 août 2021;37(8‑9):759‑72.
- 3. Semenzato L, Botton J, Baricault B, Deloumeaux J, Joachim C, Sylvestre E, et al. Estimation de l’impact de la vaccination sur le risque de formes graves de COVID-19 au sein des départements d’Outre-Mer à partir des données du Système national des données de santé (SNDS) - Résultats jusqu’au 30 septembre 2021. Revue d’Épidémiologie et de Santé Publique. 1 nov 2022; 70:S257‑8.
- 4. Bouillon K, Baricault B, Botton J, Jabagi MJ, Bertrand M, Semenzato L, et al. Estimation de l’impact de la vaccination chez les personnes âgées de 75 ans et plus sur le risque de formes graves de Covid-19 en France à partir des données du Système National des Données de Santé (SNDS) – actualisation jusqu’au 20 juillet 202. 11 oct 2021;
- 5. Lustig Y, Sapir E, Regev-Yochay G, Cohen C, Fluss R, Olmer L, et al. BNT162b2 COVID-19 vaccine and correlates of humoral immune responses and dynamics: a prospective, single-centre, longitudinal cohort study in health-care workers. The Lancet Respiratory Medicine. 1 sept 2021; 9(9):999‑1009.
- 6. Remy L, Tomomori-Sato C, Conkright-Fincham J, Wiedemann LM, Conaway JW, Unruh JR. Comparison of Antibody Levels in Response to SARS-CoV-2 Infection and Vaccination Type in a Midwestern Cohort. 10 nov 2021; 2021.08.16.21262036.
- 7. Salvagno GL, Brandon M. Henry, Pighi L, De Nitto S, Lippi G. Total Anti-SARS-CoV-2 Antibodies Measured 6 Months After Pfizer-BioNTech COVID-19 Vaccination in Healthcare Workers. 1 sept 2021 [cité 9 mars 2023]; Disponible sur: https://papers.ssrn.com/abstract=3915349
- 8. Zhong D, Xiao S, Debes AK, Egbert ER, Caturegli P, Colantuoni E, et al. Durability of Antibody Levels after Vaccination With mRNA SARS-CoV-2 Vaccine in Individuals With or Without Prior Infection. JAMA. 28 déc 2021; 326(24):2524‑6.
- 9. Liao Y, Zhang Y, Zhao H, Pu J, Zhao Z, Li D, et al. Intensified antibody response elicited by boost suggests immune memory in individuals administered two doses of SARS-CoV-2 inactivated vaccine. Emerging Microbes & Infections. 1 janv 2021; 10(1):1112‑5.
- 10. Levin EG, Lustig Y, Cohen C, Fluss R, Indenbaum V, Amit S, et al. Waning Immune Humoral Response to BNT162b2 Covid-19 Vaccine over 6 Months. New England Journal of Medicine. 9 déc 2021; 385(24):e84.
- 11. Goel RR, Painter MM, Apostolidis SA, Mathew D, Meng W, Rosenfeld AM, et al. mRNA Vaccination Induces Durable Immune Memory to SARS-CoV-2 with Continued Evolution to Variants of Concern. 23 août 2021 [cité 9 mars 2023]; Disponible sur: http://biorxiv.org/lookup/doi/10.1101/2021.08.23.457229
- 12. Kontopoulou K, Nakas C, Ainatzoglou A, Goudi G, Katsioulis C, Papazisis G. Evolution of Antibody Titers Up to 6 Months Post-Immunization With the BNT162b2 Pfizer/BioNTech Vaccine in Greece. 12 sept 2021 [cité 9 mars 2023]; Disponible sur: https://papers.ssrn.com/abstract=3922311
- 13. Ministère de la Santé et de la Population. Riposte à la COVID-19 au Congo: Rapport de situation [Internet]. République du Congo: Ministère de la Santé et de la Population; 2022 juill p. 13. Report No.: SITREP N°244. Disponible sur: https://www.afro.who.int/fr/countries/congo/publication/riposte-lepidemie-de-covid-19-au-congo-rapports-de-situation
- 14. Voumbo Matoumona Mavoungou YVY, Niama AC, Ndziessi G, Pandzou G, Bono A, Ossou-Nguiet PM. Vaccination against COVID-19: Surveillance of Adverse Events in Brazzaville. Microbiol Infect Dis [Internet]. 30 juin 2022 [cité 15 nov 2024];6(3). Disponible sur: https://www.scivisionpub.com/pdfs/vaccination-against-covid19-surveillance-of-adverse-events-in-brazzaville-2211.pdf
- 15. Ndziessi G, Niama RF, Aloumba AG, Peya JM, Ngatse JA, Ngoyomi RA, et al. Seroprevalence of SARS-CoV-2 antibodies in Republic of Congo, February 2022. Epidemiology & Infection. 11 sept 2023; 1‑29.
- 16. Aloumba GA, Niama AC, Ndziessi G, Amona M, Doukaga M, Ekat M, et al. Evaluation de la Couverture Vaccinale Anti COVID-19 auprès du Personnel de Santé des Hôpitaux de Référence de Brazzaville. 2024; 25(4).
- 17. Romero-Ibarguengoitia ME, Rivera-Salinas D, Sarti R, Levi R, Mollura M, Garza-Silva A, et al. Efficacy of Six Different SARS-CoV-2 Vaccines during a Six-Month Follow-Up and Five COVID-19 Waves in Brazil and Mexico. Vaccines (Basel). 14 avr 2023;11(4):84
References
1. Organisation mondiale de la Santé. COVID-19 epidemiological update – 6 November 2024 [Internet]. 2024 [cité 13 déc 2024]. Disponible sur: https://www.who.int/publications/m/item/covid-19-epidemiological-update-edition-173
2. Feraoun Y, Maisonnasse P, Grand RL, Beignon AS. COVID-19, des vaccins à la vitesse de l’éclair. Med Sci (Paris). 1 août 2021;37(8‑9):759‑72.
3. Semenzato L, Botton J, Baricault B, Deloumeaux J, Joachim C, Sylvestre E, et al. Estimation de l’impact de la vaccination sur le risque de formes graves de COVID-19 au sein des départements d’Outre-Mer à partir des données du Système national des données de santé (SNDS) - Résultats jusqu’au 30 septembre 2021. Revue d’Épidémiologie et de Santé Publique. 1 nov 2022; 70:S257‑8.
4. Bouillon K, Baricault B, Botton J, Jabagi MJ, Bertrand M, Semenzato L, et al. Estimation de l’impact de la vaccination chez les personnes âgées de 75 ans et plus sur le risque de formes graves de Covid-19 en France à partir des données du Système National des Données de Santé (SNDS) – actualisation jusqu’au 20 juillet 202. 11 oct 2021;
5. Lustig Y, Sapir E, Regev-Yochay G, Cohen C, Fluss R, Olmer L, et al. BNT162b2 COVID-19 vaccine and correlates of humoral immune responses and dynamics: a prospective, single-centre, longitudinal cohort study in health-care workers. The Lancet Respiratory Medicine. 1 sept 2021; 9(9):999‑1009.
6. Remy L, Tomomori-Sato C, Conkright-Fincham J, Wiedemann LM, Conaway JW, Unruh JR. Comparison of Antibody Levels in Response to SARS-CoV-2 Infection and Vaccination Type in a Midwestern Cohort. 10 nov 2021; 2021.08.16.21262036.
7. Salvagno GL, Brandon M. Henry, Pighi L, De Nitto S, Lippi G. Total Anti-SARS-CoV-2 Antibodies Measured 6 Months After Pfizer-BioNTech COVID-19 Vaccination in Healthcare Workers. 1 sept 2021 [cité 9 mars 2023]; Disponible sur: https://papers.ssrn.com/abstract=3915349
8. Zhong D, Xiao S, Debes AK, Egbert ER, Caturegli P, Colantuoni E, et al. Durability of Antibody Levels after Vaccination With mRNA SARS-CoV-2 Vaccine in Individuals With or Without Prior Infection. JAMA. 28 déc 2021; 326(24):2524‑6.
9. Liao Y, Zhang Y, Zhao H, Pu J, Zhao Z, Li D, et al. Intensified antibody response elicited by boost suggests immune memory in individuals administered two doses of SARS-CoV-2 inactivated vaccine. Emerging Microbes & Infections. 1 janv 2021; 10(1):1112‑5.
10. Levin EG, Lustig Y, Cohen C, Fluss R, Indenbaum V, Amit S, et al. Waning Immune Humoral Response to BNT162b2 Covid-19 Vaccine over 6 Months. New England Journal of Medicine. 9 déc 2021; 385(24):e84.
11. Goel RR, Painter MM, Apostolidis SA, Mathew D, Meng W, Rosenfeld AM, et al. mRNA Vaccination Induces Durable Immune Memory to SARS-CoV-2 with Continued Evolution to Variants of Concern. 23 août 2021 [cité 9 mars 2023]; Disponible sur: http://biorxiv.org/lookup/doi/10.1101/2021.08.23.457229
12. Kontopoulou K, Nakas C, Ainatzoglou A, Goudi G, Katsioulis C, Papazisis G. Evolution of Antibody Titers Up to 6 Months Post-Immunization With the BNT162b2 Pfizer/BioNTech Vaccine in Greece. 12 sept 2021 [cité 9 mars 2023]; Disponible sur: https://papers.ssrn.com/abstract=3922311
13. Ministère de la Santé et de la Population. Riposte à la COVID-19 au Congo: Rapport de situation [Internet]. République du Congo: Ministère de la Santé et de la Population; 2022 juill p. 13. Report No.: SITREP N°244. Disponible sur: https://www.afro.who.int/fr/countries/congo/publication/riposte-lepidemie-de-covid-19-au-congo-rapports-de-situation
14. Voumbo Matoumona Mavoungou YVY, Niama AC, Ndziessi G, Pandzou G, Bono A, Ossou-Nguiet PM. Vaccination against COVID-19: Surveillance of Adverse Events in Brazzaville. Microbiol Infect Dis [Internet]. 30 juin 2022 [cité 15 nov 2024];6(3). Disponible sur: https://www.scivisionpub.com/pdfs/vaccination-against-covid19-surveillance-of-adverse-events-in-brazzaville-2211.pdf
15. Ndziessi G, Niama RF, Aloumba AG, Peya JM, Ngatse JA, Ngoyomi RA, et al. Seroprevalence of SARS-CoV-2 antibodies in Republic of Congo, February 2022. Epidemiology & Infection. 11 sept 2023; 1‑29.
16. Aloumba GA, Niama AC, Ndziessi G, Amona M, Doukaga M, Ekat M, et al. Evaluation de la Couverture Vaccinale Anti COVID-19 auprès du Personnel de Santé des Hôpitaux de Référence de Brazzaville. 2024; 25(4).
17. Romero-Ibarguengoitia ME, Rivera-Salinas D, Sarti R, Levi R, Mollura M, Garza-Silva A, et al. Efficacy of Six Different SARS-CoV-2 Vaccines during a Six-Month Follow-Up and Five COVID-19 Waves in Brazil and Mexico. Vaccines (Basel). 14 avr 2023;11(4):84