Factors associated with COVID-19 vaccine hesitancy among health personnel in Yaounde, Cameroon

Background. Health care personnel constitute a group at high risk of contracting COVID-19. However, the vaccination rate in this group in our context remains low. The objective of our study was to determine the factors associated with COVID-19 vaccine hesitancy among health care workers in Yaounde. Methods.We conducted a cross-sectional study of 360 health personnel in three hospitals in the city of Yaounde from January to March 2022, i.e., 3 months. All health personnel who gave their free consent were included. Ethical clearance was obtained from the Institutional Ethics and Research Committee of the Faculty of Medicine and Biomedical Sciences of the University of Yaounde I. A logistic regression was performed to search for factors associated with reluctance to vaccinate, with a significance level of 0.05. Results.The vaccination rate against COVID-19 was 34% (123). Factors associated with vaccine hesitancy were female gender (OR [95% CI] =3.5[2.2-5.5]; p<0.001), working outside a COVID-19 management unit (OR [95% CI]=6, [2.1-18.5]; p=0.001), fear of the harmfulness of COVID-19 vaccines (OR [CI 95%] =2.7[1.7-4.2]; p<0.001), and doubt of vaccine efficacy (OR [CI 95%] =4.0[2.5-6.4]; p<0.001). Conclusion:Health personnel are still reluctant to vaccinate in our context. Factors associated with hesitancy to vaccination against COVID-19 could help deconstruct apprehensions.

Introduction. La pandémie de la COVID-19 a ajouté un fardeau supplémentaire dans les pays aux systèmes de santé déjà fragiles. Objectif : déterminer la prévalence et la séroprévalence de la COVID-19 en cas de suspicion du paludisme au cours de la deuxième vagueà Yaoundé. Méthodologie. Une étude transversale descriptive a été menée au Centre Médical le Jourdain pendant 8 semaines du 19 Avril au 13 Juin 2021 soit durant la deuxième vague au Cameroun. Pour les 86 patients avec suspicion de paludisme, des prélèvements nasopharyngé et sanguins ont été réalisés pour la recherche d'antigène du SRAS- CoV 2 et des IgG et IgM anti-SARS-CoV-2 grâce aux kits STANDARDTM Q COVID-19 Ag de SD BIOSENSOR, Corée, 2020 et StandardTM Q COVID 19 Ac IgG/IgM de SD BIOSENSOR, Corée, 2020 respectivement. La confirmation du paludisme a été faite grâce à l'examen microscopique des étalements de sang colorés. Résultats. Le paludisme était confirmé dans 20,9% (18) des cas. Les prévalences de la COVID-19 et de la coïnfection COVID19/Paludisme étaient de 8,1% et de 0,9% respectivement. Sur les 25,6% (54) des patients avec des IgM anti-COVID-19, aucun cas de microscopie positive n'a été retrouvé. Par ailleurs un peu plus de la moitié des patients avaient des anticorps IgG anti-COVID-19 qu'ils aient une goutte épaisse positive ou pas soit 56,0% (42/75) et 52,2% (71/136) respectivement. Conclusion. En cas de suspicion du paludisme en zone impaludée, il parait non négligeable de considérer la COVID-19 comme un diagnostic différentiel.

Lack of efficacy of the standard potency Edmonston-Zagreb live, attenuated measles vaccine in African infants

The efficacy of standard potency Edmonston-Zagreb (E-Z) measles vaccine was tested in a randomized trial of Black infants in a rural area of South Africa where a measles epidemic was occurring. The following immunization schedules were used: 48 infants aged 4-8.5 months who received 3.9 log 50 infectious units of E-Z vaccine (group A); 48 infants aged 4-8.5 months who received 3.28 log 50 infectious units of Schwarz vaccine (group B); and 28 infants aged greater than 9 months who received 3.28 log 50 infectious units of Schwarz vaccine and served as controls (group C). For infants aged less than 23 weeks who were given either the E-Z or Schwarz vaccine, the number of seropositives was low (28%), irrespective of the pre-vaccination level of measles antibody. There was a higher number of seropositives (68%) among those in the age range greater than 23 weeks to less than 36 weeks who received the E-Z vaccine rather than the Schwarz vaccine (36%). When administered to children aged greater than 36 weeks, the Schwarz vaccine produced a satisfactory, though suboptimal response rate (61%). There was no correlation between seropositivity and pre-vaccination measles antibody status. Use of the standard dose of E-Z vaccine may have been one of the factors for this poor response, and this supports the WHO recommendation that titres higher than the standard potency vaccine are needed if 6-month-old infants are to be successfully immunized against measles