Journal Article > ResearchFull Text
PLOS Glob Public Health. 8 June 2023; Volume 3 (Issue 6); e0001457.; DOI:10.1371/journal.pgph.0001457
Simons E, Nikolay B, Ouedraogo P, Pasquier E, Tiemeni C, et al.
PLOS Glob Public Health. 8 June 2023; Volume 3 (Issue 6); e0001457.; DOI:10.1371/journal.pgph.0001457
Although seroprevalence studies have demonstrated the wide circulation of SARS-COV-2 in African countries, the impact on population health in these settings is still poorly understood. Using representative samples of the general population, we evaluated retrospective mortality and seroprevalence of anti-SARS-CoV-2 antibodies in Lubumbashi and Abidjan. The studies included retrospective mortality surveys and nested anti-SARS-CoV-2 antibody prevalence surveys. In Lubumbashi the study took place during April-May 2021 and in Abidjan the survey was implemented in two phases: July-August 2021 and October-November 2021. Crude mortality rates were stratified between pre-pandemic and pandemic periods and further investigated by age group and COVID waves. Anti-SARS-CoV-2 seroprevalence was quantified by rapid diagnostic testing (RDT) and laboratory-based testing (ELISA in Lubumbashi and ECLIA in Abidjan). In Lubumbashi, the crude mortality rate (CMR) increased from 0.08 deaths per 10 000 persons per day (pre-pandemic) to 0.20 deaths per 10 000 persons per day (pandemic period). Increases were particularly pronounced among <5 years old. In Abidjan, no overall increase was observed during the pandemic period (pre-pandemic: 0.05 deaths per 10 000 persons per day; pandemic: 0.07 deaths per 10 000 persons per day). However, an increase was observed during the third wave (0.11 deaths per 10 000 persons per day). The estimated seroprevalence in Lubumbashi was 15.7% (RDT) and 43.2% (laboratory-based). In Abidjan, the estimated seroprevalence was 17.4% (RDT) and 72.9% (laboratory-based) during the first phase of the survey and 38.8% (RDT) and 82.2% (laboratory-based) during the second phase of the survey. Although circulation of SARS-CoV-2 seems to have been extensive in both settings, the public health impact varied. The increases, particularly among the youngest age group, suggest indirect impacts of COVID and the pandemic on population health. The seroprevalence results confirmed substantial underdetection of cases through the national surveillance systems.
Journal Article > ResearchFull Text
Afr J Biotechnol. 28 February 2009; Volume 8 (Issue 4); 536-546.; DOI:10.5897/AJB2009.000-9091
Ahoua L, Guetta AN, Ekaza E, Bouzid S, N’Guessan R, et al.
Afr J Biotechnol. 28 February 2009; Volume 8 (Issue 4); 536-546.; DOI:10.5897/AJB2009.000-9091
A case-control study was carried out in 3 highly endemic regions of Côte d’Ivoire to study risk factors for Buruli ulcer. A case was defined as a Buruli ulcer occurring less than one year before the date of survey, resident in one of the regions investigated and there was no history of Buruli ulcer illness. Controls were selected from the general population by a two stage cluster sampling method. A total of 116 cases and 116 controls were included. For the cases, the male/female sex ratio was 0.84, the median age was 19.5 years and 40.5% were children 15 years. Biological results were obtained for 86 (74%) cases using skin exudate samples. Positive rates were 22.0, 22.1 and 27.9% respectively for smear examination, culture and PCR IS2404, respectively. After adjusting for possible confounders, no history of BCG vaccination (ORa = 5.0, CI 1.7 - 14.3), presence of a case 15 years (ORa = 8.3, CI 2.8 -24.1), having a river/lake/dam near the housing (ORa = 4.4, CI 1.6 - 12.2) and the type of place for fishing (p = 0.001) were associated with illness. Young children and women having daily water related activities were most at risk. Swab samples were not sensitive enough for Buruli ulcer diagnosis. There is an urgent need for a rapid field test to diagnosis Buruli Ulcer as PCR IS2404 remains expensive for most of the endemic countries.
Journal Article > ResearchAbstract Only
Science. 10 November 2017; Volume 358 (Issue 6364); 785-789.; DOI:10.1126/science.aad5901
Weill FX, Domman D, Njamkepo E, Tarr C, Rauzier J, et al.
Science. 10 November 2017; Volume 358 (Issue 6364); 785-789.; DOI:10.1126/science.aad5901
The seventh cholera pandemic has heavily affected Africa, although the origin and continental spread of the disease remain undefined. We used genomic data from 1070 Vibrio cholerae O1 isolates, across 45 African countries and over a 49-year period, to show that past epidemics were attributable to a single expanded lineage. This lineage was introduced at least 11 times since 1970, into two main regions, West Africa and East/Southern Africa, causing epidemics that lasted up to 28 years. The last five introductions into Africa, all from Asia, involved multidrug-resistant sublineages that replaced antibiotic-susceptible sublineages after 2000. This phylogenetic framework describes the periodicity of lineage introduction and the stable routes of cholera spread, which should inform the rational design of control measures for cholera in Africa.