Crimean Congo hemorrhagic fever virus exposure among febrile patients, cattle herders, and cattle herds in Cameroon.

Problem Addressed: Crimean Congo hemorrhagic fever (CCHF) is a tick-borne disease with high fatality rates and an expansive geographic distribution, yet disease prevalence data in Cameroon is lacking.

Objective: This study aimed to determine CCHF virus (CCHFV) seroprevalence and tick distribution among cattle herders and febrile patients in West and Centre Cameroon.

Methods And Approach: Two cross-sectional serological studies of human and cattle were conducted from October to December 2021 and from June to July 2022, which included the collection of ticks.

The Global Measles and Rubella Laboratory Network Supports High-Quality Surveillance.

With 762 laboratories, the Global Measles and Rubella Laboratory Network (GMRLN) is the largest laboratory network coordinated by the World Health Organization (WHO). Like the Global Polio Laboratory Network, the GMRLN has multiple tiers, including global specialized laboratories, regional reference laboratories, national laboratories, and, in some countries, subnational laboratories. Regional networks are supervised by regional laboratory coordinators reporting to a global coordinator at WHO headquarters.

Clinical description of dengue and chikungunya virus infections amongst acute febrile patients in a malaria endemic area of Mfou, the Centre region of Cameroon.

This study aims to determine the frequency and clinical manifestations of dengue and chikungunya viral infections in the district hospital of Mfou, Centre region of Cameroon where malaria is endemic. Blood samples were collected from suspected cases and tested for Plasmodium parasites and for the molecular detection of viral RNAs (dengue, zika and chikungunya viruses) using TRIOPLEX qPCR. A total of 108 patients were clinically suspected among which 25 % were male and 50 % were less than 15.

Assessment of Dengue and Chikungunya Infections among Febrile Patients Visiting Four Healthcare Centres in Yaoundé and Dizangué, Cameroon.

Dengue and chikungunya are now widely distributed in Cameroon, but there is still not enough information on their prevalence in different epidemiological settings. This study was undertaken to assess the prevalence of dengue and chikungunya in both urban and rural settings in Cameroon using three diagnostic tools. From December 2019 to September 2021, willing febrile (temperature >38 °C) outpatients visiting four healthcare facilities in the cities of Yaoundé and Dizangué were screened for dengue, and chikungunya.

Plants extracts from Cameroon pharmacopeia strongly inhibit the Chikungunya virus infection by targeting entry and replication steps.

Ethnopharmacological Relevance: Cameroon is one of the sub-Saharan African countries affected by Chikungunya virus (CHIKV). With the absence of approved treatment, this disease represents globally a major public health concern. Several plants are traditionally used in Cameroon for the treatment of virus induced fever and arthralgia.

Sustained circulation of yellow fever virus in Cameroon: an analysis of laboratory surveillance data, 2010-2020.

Background: The re-emergence of yellow fever poses a serious public health risk to unimmunized communities in the tropical regions of Africa and South America and unvaccinated travelers visiting these regions. This risk is further accentuated by the likely spread of the virus to areas with potential for yellow fever transmission such as in Asia, Europe, and North America. To mitigate this risk, surveillance of yellow fever is pivotal.

Chikungunya viruses containing the A226V mutation detected retrospectively in Cameroon form a new geographical subclade.

Background: Chikungunya virus (CHIKV) is a re-emerging arbovirus associated with sporadic outbreaks in Cameroon since 2006. Viral whole genomes were generated to analyze the origins of evolutionary lineages, the potential of emergence/re-emergence, and to infer transmission dynamics of recent Cameroon CHIKV outbreak strains.

Methods: Samples collected between 2016 and 2019 during CHIKV outbreaks in Cameroon were screened for CHIKV using reverse transcription PCR (RT-PCR), followed by whole genome sequencing of positive samples.

Laboratory capacity assessments in 25 African countries at high risk of yellow fever, August-December 2018.

Introduction: accurate and timely laboratory diagnosis of yellow fever (YF) is critical to the Eliminate Yellow Fever Epidemics (EYE) strategy. Gavi, the Vaccine Alliance recognized the need to support and build capacity in the national and regional laboratories in the Global YF Laboratory Network (GYFLN) as part of this strategy.

Methods: to better understand current capacity, gaps and needs of the GYFLN laboratories in Africa, assessments were carried out in national and regional reference laboratories in the 25 African countries at high risk for YF outbreaks that were eligible for new financial support from Gavi.

Technical viability of the YF MAC-HD ELISA kit for use in yellow fever-endemic regions.

Yellow fever (YF), an arboviral disease, affects an estimated 200,000 people and causes 30,000 deaths per year and recently has caused major epidemics in Africa and South America. Timely and accurate diagnosis of YF is critical for managing outbreaks and implementing vaccination campaigns. A YF immunoglobulin M (IgM) antibody-capture (MAC) enzyme-linked immunosorbent assay (ELISA) kit, the YF MAC-HD, was successfully introduced starting in 2018 to laboratories in Africa and South America.

Molecular characterization of measles virus strains circulating in Cameroon during the 2013-2016 epidemics.

The first genotyping data on measles virus (MeV) strains in Cameroon dates from 1994, while other studies were realized in 2001 and 2011 with the establishment of MeV virological surveillance. However, the genetic data of MeV strains circulating in Cameroon remains fragmented and concentrated in certain regions, hence the need for an update. The objective of this study was to have recent data on MeV genotypes circulating in Cameroon.

Dengue virus infection in people residing in Africa: a systematic review and meta-analysis of prevalence studies.

Better knowledge of the face of the current dengue virus (DENV) epidemiology in Africa can help to implement efficient strategies to curb the burden of dengue fever. We conducted this systematic review and meta-analysis to determine the prevalence of DENV infection in Africa. We searched PubMed, EMBASE, African Journals Online, and Africa Index Medicus from January 1, 2000 to June 10, 2019 without any language restriction.

Case fatality rate and risk factors for Nipah virus encephalitis: A systematic review and meta-analysis.

Background: A wide range of Nipah virus (NiV) encephalitis case fatality rates (CFR) have been reported. Data on the involvement of several potential risk factors in Nipah virus transmission remain controversial. We performed a systematic review and meta-analysis to estimate the pooled CFR of NiV encephalitis and to assess the risk factors for NiV infection.

Investigation of an Outbreak of Dengue Virus Serotype 1 in a Rural Area of Kribi, South Cameroon: A Cross-Sectional Study.

Background: On May 2017, a case of dengue serotype 1 was detected and confirmed through routine surveillance in a traveler returning from Kribi, a seaside town of Southern Cameroon. This study aimed at confirming the circulation of dengue virus (DENV) in Southern Cameroon.

Methods: A cross sectional study was carried out in Londji near Kribi from June 21-25, 2017, by a joint team of Centre Pasteur of Cameroon and the Department of Diseases, Epidemics and Pandemics Control.

Detection and serotyping of dengue viruses in febrile patients consulting at the New-Bell District Hospital in Douala, Cameroon.

Arboviruses are a major public health problem worldwide and are predominantly present in intertropical areas. Chikungunya, dengue and zika viruses have been implicated in recent epidemics in Asia, America and Africa. In Cameroon, data on these viruses are fragmentary.

First documented evidence of dengue and malaria co-infection in children attending two health centers in Yaoundé, Cameroon.

To date, only a few cases of malaria and dengue co-infections have been reported around the world. We describe for the first time in Cameroon, concurrent infections among children (2 to 10 years) in two health centers of Yaoundé. The two dengue strains isolated in Cameroon clustered with the Asian II genotype.

Serological evidence of rift valley fever Phlebovirus and Crimean-Congo hemorrhagic fever orthonairovirus infections among pygmies in the east region of Cameroon.

Background: Rift Valley Fever Phlebovirus (RVFV) and Crimean-Congo Hemorrhagic Fever Orthonairovirus (CCHFV) specific antibodies had been documented among humans in urban settings of the southwestern and northern Cameroon in the late 1980s. Recently, evidence for enzootic circulation of RVFV was reported among livestock in both rural and urban settings in Cameroon. However, current estimates of human exposure to RVFV and CCHFV are still to be documented in Cameroon, especially in rural areas.

Importation and outbreak of wild polioviruses from 2000 to 2014 and interruption of transmission in Cameroon.

Background: Efficient implementation of the global eradication strategies consisting of Acute Flaccid Paralysis (AFP) surveillance and mass immunization campaigns led to interruption of indigenous wild poliovirus transmission in Cameroon in 1999.

Objectives: This study describes type 1 and type 3 wild poliovirus (WPV) importation, incidence, geographic distribution and control since the original interruption of transmission in Cameroon.

Study Design: Stool samples from AFP patients under the age of 15 years in Cameroon were collected nationwide and subjected to virus isolation on RD and L20B cell cultures.

Molecular characterization of chikungunya virus from three regions of Cameroon.

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Circulating vaccine-derived polioviruses in the Extreme North region of Cameroon.

Background: The World Health Organization (WHO) poliovirus eradication program includes careful surveillance of acute-flaccid paralysis (AFP) and mass and routine immunization with oral polio vaccine (OPV). In populations with low vaccine coverage, the live-attenuated Sabin strains, OPV types 1, 2 and 3, can evolve into virulent vaccine-derived polioviruses (VDPVs) and circulate in the community. Until recently, circulating VDPVs (cVDPVs) had not been reported in Cameroon despite the fact that VDPV2 outbreaks have occurred in nearby countries.

Laboratory data of dog rabies in southern Cameroon from 2010 to 2013.

Background: Dog rabies is endemic in most African countries and the risk of human rabies is estimated to be high in Cameroon according to WHO estimations in 2010. This study aimed to describe the circulation rabies virus (RABV) among dogs in the southern regions of Cameroon from 2010 to 2013 in a context, where mass vaccination campaigns are launched annually in order to control rabies in domestic animals including dogs and cats.

Findings: From 2010 to 2013, 93 animal specimens (dogs: 91, monkey: 1, pig: 1) originating from the southern regions of Cameroon were collected and tested for rabies virus at the Centre Pasteur of Cameroon by fluorescent antibody test (FAT) and virus isolation.