Snakebites in Cameroon: Tolerance of a Snake Antivenom (Inoserp™ PAN-AFRICA) in Africa in Real-Life Conditions.

Snakebite envenomation (SBE) is a public health issue in sub-Saharan countries. Antivenom is the only etiological treatment. Excellent tolerance is essential in managing SBE successfully. This study aimed to evaluate tolerance of InoserpTM PAN-AFRICA (IPA). It was conducted on fourteen sites across Cameroon. IPA was administered intravenously and repeated at the same dose every two hours if needed. Early and late tolerance was assessed by the onset of clinical signs within two hours and at a visit two weeks or more after the first IPA administration, respectively. Over 20 months, 447 patients presenting with a snakebite were included. One dose of IPA was administered to 361 patients and repeated at least once in 106 patients. No significant difference was shown between the proportion of adverse events in patients who received IPA (266/361, 73.7%) and those who did not (69/85, 81.2%) (p = 0.95). Adverse reactions, probably attributable to IPA, were identified in four (1.1%) patients, including one severe (angioedema) and three mild. All these reactions resolved favorably. None of the serious adverse events observed in twelve patients were attributed to IPA. No signs of late intolerance were observed in 302 patients. Tolerance appears to be satisfactory. The availability of effective and well-tolerated antivenoms would reduce the duration of treatment and prevent most disabilities and/or deaths.

Real life condition evaluation of Inoserp PAN-AFRICA antivenom effectiveness in Cameroon.

BACKGROUND: Snakebites is a serious public health issue but remains a neglected tropical disease. Data on antivenom effectiveness are urgently needed in Africa. We assessed effectiveness of Inoserp PAN-AFRICA (IPA), the recommended antivenom available in Cameroon. METHODOLOGY/PRINCIPAL FINDINGS: We enrolled 447 patients presenting with snakebite in 14 health facilities across Cameroon. At presentation, cytotoxicity, coagulation troubles and neurotoxicity were graded. We administered two to four vials of antivenom to patients based on hemotoxic or neurotoxic signs. We renewed antivenom administration to patients with persistence of bleedings or neurotoxicity 2 hours after each injection. We defined early improvement as a reduction of the grade of envenomation symptoms 2 hours after first injection. Medium-term effectiveness was investigated looking at disappearance of symptoms during hospitalization. After hospital discharge, a home visit was planned to assess long-term outcomes. Between October 2019 and May 2021, we enrolled 447 (93.7%), including 72% from the savannah regions. The median [IQR] age was 25 [14-40]. Envenomation was diagnosed in 369 (82.6%) participants. The antivenom was administered to 356 patients (96.5%) of whom 256 (71.9%) received one administration. Among these patients, cytotoxic symptoms were observed in 336 (94.4%) participants, coagulation disorders in 234 (65.7%) participants and neurotoxicity in 23 (6.5%) participants. Two hours after the first administration of antivenom, we observed a decrease in coagulation disorders or neurotoxicity in 75.2% and 39.1% of patients, respectively. Complete cessation of bleedings and neurotoxicity occurred in 96% and 93% of patients within 24 hours, respectively. Sequelae have been observed in 9 (3%) patients at the home visit 15 days after hospital admission and 11 (3%) died including one before antivenom injection. CONCLUSIONS/SIGNIFICANCE: We confirmed good effectiveness of the IPA and highlighted the rapid improvement in bleeding or neurotoxicity after the first administration. Sequential administrations of low doses of antivenom, rigorously assessed at short intervals for an eventual renewal, can preserve patient safety and save antivenom. TRIAL REGISTRATION: NCT03326492.

Residual risk of mother-to-child transmission of hepatitis B virus infection despite timely birth-dose vaccination in Cameroon (ANRS 12303): a single-centre, longitudinal observational study.

BACKGROUND: In sub-Saharan Africa, administration of hepatitis B virus (HBV) birth-dose vaccines remains suboptimal. Evidence is scarce on whether African countries should focus on increasing vaccine coverage or developing strategies incorporating additional measures, such as peripartum antiviral prophylaxis to pregnant women at high risk. To better inform decision makers, we estimated the residual risk of mother-to-child transmission despite HBV birth-dose vaccine in Cameroon. METHODS: We did a single-centre, longitudinal observational study. Pregnant women were systematically screened for HBV surface antigen (HBsAg) at Tokombéré District Hospital (Tokombéré district, Cameroon). Children born to HBsAg-positive mothers in 2009-16 who received the HBV birth-dose vaccine and three subsequent doses of pentavalent vaccine at 6, 10, and 14 weeks were followed up prospectively in 2015-17. In children, capillary blood was obtained for HBsAg rapid test and dried blood spots to quantify HBV DNA concentrations. Venous blood was also collected from HBsAg-positive children. Mother-to-child transmission was confirmed by whole-genome sequencing. FINDINGS: Between Jan 31, 2009, and Dec 31, 2016, 22 243 (66·8%) of 33 309 pregnant women accepted antenatal HBV screening, of whom 3901 (17·5%) were HBsAg positive. 2004 (51·4%) of 3901 children who were born to HBsAg-positive mothers received the HBV birth-dose vaccine, of whom 1800 (89·8%) also completed the three-dose pentavalent vaccine. In total, the current analysis included 607 children who had a follow-up serosurvey. The prevalence of HBsAg was 5·6% in children who received the birth-dose vaccine in less than 24 h, 7·0% in those who received it 24-47 h after birth, and 16·7% in those who received it 48-96 h after birth (ptrend=0·083). 35 (89·7%) of 39 infected children were born to mothers positive for HBV e antigen with high HBV DNA of 5·3 log10 IU/mL or more. Whole-genome sequencing of HBV in infected mother-child pairs confirmed high identity proportions of 99·97-100%. INTERPRETATION: We documented a substantial risk of mother-to-child transmission despite timely administration of the HBV birth-dose vaccine within 24 h after birth. To reach WHO's elimination targets, peripartum antiviral prophylaxis might be required in parts of Africa, in addition to increasing coverage of the HBV birth-dose vaccine. FUNDING: Agence nationale de recherches sur le sida et les hépatites virales (ANRS).

Prevalence, awareness, treatment, and control of hypertension among rural and urban dwellers of the Far North Region of Cameroon.

OBJECTIVE: To assess the prevalence and determinants of high blood pressure (BP) and awareness, treatment, and control rates in the Far North Region of Cameroon, where these variables have not been explored so far. METHODS: In total, 889 individuals (41.5% women) aged at least 18 years participated in a cross-sectional survey conducted in Maroua (urban area) and Tokombere (rural area) from November 2014 to May 2015, using a multistage cluster sampling frame. Anthropometric variables, BP, and fasting capillary glucose were assessed in all participants. Hypertension was defined as BP at least 140/90 mmHg or antihypertensive therapy and BP control as BP less than 140/90 mmHg. Prevalence estimates were age standardized to the Cameroon population. RESULTS: The prevalence of hypertension was 37.8% (rural: 34%; urban: 41.2%; men: 38.8%; women: 37.9%). Hypertension was associated with urban environment (odds ratio: 1.42; 95%; confidence interval 1.06-1.89), age at least 70 years (4.06; 2.02-6.14), male sex (4.06; 2.02-6.14), abdominal obesity (2.36; 1.54-3.61), and high blood sugar (2.01; 1.31-3.08). Among individuals with hypertension, 18.6% (rural: 17.9%; urban: 19.5%) were aware of having high BP. Among those aware, 29.3% (rural: 17.3%; urban: 36.3%) reported receiving treatment, of whom 16.3% (rural: 22.6%; urban: 4.2%) had BP controlled. Awareness, treatment, and BP control levels were higher in women than men. CONCLUSION: Hypertension is highly prevalent in Far North Cameroon and awareness, treatment, and control rates are low. Efforts to improve detection, treatment, and control of hypertension in Cameroon are needed.