Reported antibiotic use among patients in the multicenter ANDEMIA infectious diseases surveillance study in sub-saharan Africa.

BACKGROUND: Exposure to antibiotics has been shown to be one of the drivers of antimicrobial resistance (AMR) and is critical to address when planning and implementing strategies for combatting AMR. However, data on antibiotic use in sub-Saharan Africa are still limited. Using hospital-based surveillance data from the African Network for Improved Diagnostics, Epidemiology and Management of Common Infectious Agents (ANDEMIA), we assessed self-reported antibiotic use in multiple sub-Saharan African countries. METHODS: ANDEMIA included 12 urban and rural health facilities in Côte d'Ivoire, Burkina Faso, Democratic Republic of the Congo, and Republic of South Africa. Patients with acute respiratory infection (RTI), acute gastrointestinal infection (GI) and acute febrile disease of unknown cause (AFDUC) were routinely enrolled, and clinical, demographic, socio-economic and behavioral data were collected using standardized questionnaires. An analysis of ANDEMIA data from February 2018 to May 2022 was conducted. Reported antibiotic use in the ten days prior to study enrolment were described by substance and by the WHO AWaRe classification ("Access", "Watch", "Reserve", and "Not recommended" antibiotics). Frequency of antibiotic use was stratified by location, disease syndrome and individual patient factors. RESULTS: Among 19,700 ANDEMIA patients, 7,258 (36.8%) reported antibiotic use. A total of 9,695 antibiotics were reported, including 54.7% (n = 5,299) from the WHO Access antibiotic group and 44.7% (n = 4,330) from the WHO Watch antibiotic group. The Watch antibiotic ceftriaxone was the most commonly reported antibiotic (n = 3,071, 31.7%). Watch antibiotic use ranged from 17.4% (56/322) among RTI patients in Côte d'Ivoire urban facilities to 73.7% (630/855) among AFDUC patients in Burkina Faso urban facilities. Reported antibiotic use included WHO Not recommended antibiotics but no Reserve antibiotics. CONCLUSIONS: Reported antibiotic use data from this multicenter study in sub-Saharan Africa revealed a high proportion of WHO Watch antibiotics. Differences in Watch antibiotic use were found by disease syndrome, country and health facility location, which calls for a more differentiated approach to antibiotic use interventions including further evaluation of accessibility and affordability of patient treatment.

HIV viral load testing and monitoring in Côte d'Ivoire: A survival analysis of viral load testing and suppression, and evaluation of adherence to national recommendations.

Routine viral load (VL) monitoring is the standard of care in Côte d'Ivoire and allows for effective treatment guidance for people living with human immunodeficiency virus (HIV) to reach viral load suppression (VLS). For VL monitoring to be effective in reducing the impact of HIV, it must be provided in accordance with national guidance. This study aimed to evaluate VL testing, VLS rates and adherence to national guidance for VL testing using data collected from three national laboratories. We collected data on VL testing between 2015-2018 from OpenELIS (OE), an open-source electronic laboratory information system. We merged data by unique patient ID for patients (0-80 years old) who received multiple VL tests to calculate time between tests. We defined VLS as HIV RNA ≤1,000 copies/mL based on Côte d'Ivoire national and WHO guidance at the time of data collection. We used the Kaplan-Meier survival estimator to estimate time between ART (antiretroviral therapy) initiation and the first VL test, time between subsequent VL tests, and to estimate the proportion of people living with HIV (PLHIV) who were virally suppressed within 12 months of ART initiation. At the first documented VL test, 79.6% of patients were virally suppressed (95% CI: 78.9-80.3). Children under 15 were the least likely to be virally suppressed (55.2%, 95% CI: 51.5-58.8). The median time from ART initiation to the first VL sample collection for testing was 7.8 months (IQR:6.2-13.4). 72.4% of patients were virally suppressed within one year of treatment initiation (95% CI:71.5-73.3). Approximately 30% of patients received a second VL test during the 4-year study period. The median time between the first and second VL tests was 24.9 months (IQR: 4.7->40). Most PLHIV received their first VL test within the recommended 12 months of ART initiation but did not receive subsequent VL monitoring tests within the recommended time frame, reducing the benefits of VL monitoring. While VLS was fairly high, children were least likely to be virally suppressed. Our findings highlight the importance of regular VL monitoring after the first VL test, especially for children.

Subregional origins of emerging SARS-CoV-2 variants during the second pandemic wave in Côte d'Ivoire.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with increased transmissibility, virulence and immune escape abilities have heavily altered the COVID-19 pandemic's course. Deciphering local and global transmission patterns of those variants is thus key in building a profound understanding of the virus' spread around the globe. In the present study, we investigate SARS-CoV-2 variant epidemiology in Côte d'Ivoire, Western sub-Saharan Africa. We therefore generated 234 full SARS-CoV-2 genomes stemming from Central and Northern Côte d'Ivoire. Covering the first and second pandemic wave the country had been facing, we identified 20 viral lineages and showed that in Côte d'Ivoire the second pandemic wave in 2021 was driven by the spread of the Alpha (B.1.1.7) and Eta (B.1.525) variant. Our analyses are consistent with a limited number of international introductions of Alpha and Eta into Côte d'Ivoire, and those introduction events mostly stemmed from within the West African subregion. This suggests that subregional travel to Côte d'Ivoire had more impact on local pandemic waves than direct intercontinental travel.

Multicountry study of SARS-CoV-2 and associated risk factors among healthcare workers in Côte d'Ivoire, Burkina Faso and South Africa.

BACKGROUND: Reports on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread across Africa have varied, including among healthcare workers (HCWs). This study assessed the comparative SARS-CoV-2 burden and associated risk factors among HCWs in three African countries. METHODS: A multicentre study was conducted at regional healthcare facilities in Côte d'Ivoire (CIV), Burkina Faso (BF) and South Africa (SA) from February to May 2021. HCWs provided blood samples for SARS-CoV-2 serology and nasopharyngeal/oropharyngeal swabs for testing of acute infection by polymerase chain reaction and completed a questionnaire. Factors associated with seropositivity were assessed with logistic regression. RESULTS: Among 719 HCWs, SARS-CoV-2 seroprevalence was 34.6% (95% confidence interval 31.2 to 38.2), ranging from 19.2% in CIV to 45.7% in BF. A total of 20 of 523 (3.8%) were positive for acute SARS-CoV-2 infection. Female HCWs had higher odds of SARS-CoV-2 seropositivity compared with males, and nursing staff, allied health professionals, non-caregiver personnel and administration had higher odds compared with physicians. HCWs also reported infection prevention and control (IPC) gaps, including 38.7% and 29% having access to respirators and IPC training, respectively, in the last year. CONCLUSIONS: This study was a unique comparative HCW SARS-CoV-2 investigation in Africa. Seroprevalence estimates varied, highlighting distinctive population/facility-level factors affecting COVID-19 burden and the importance of established IPC programmes to protect HCWs and patients.

Staphylococcus schweitzeri-An Emerging One Health Pathogen?

The Staphylococcus aureus-related complex is formed by the Staphylococcus aureus, Staphylococcus schweitzeri, Staphylococcus argenteus, Staphylococcus roterodami and Staphylococcus singaporensis. Within this complex, S. schweitzeri is the only species mainly found in African wildlife, but it is rarely detected as a colonizer in humans or as a contaminant of fomites. The few detections in humans are most likely spillover events after contact with wildlife. However, since S. schweitzeri can be misidentified as S. aureus using culture-based routine techniques, it is likely that S. schweitzeri is under-reported in humans. The low number of isolates in humans, though, is consistent with the fact that the pathogen has typical animal adaptation characteristics (e.g., growth kinetics, lack of immune evasion cluster and antimicrobial resistance); however, evidence from selected in vitro assays (e.g., host cell invasion, cell activation, cytotoxicity) indicate that S. schweitzeri might be as virulent as S. aureus. In this case, contact with animals colonized with S. schweitzeri could constitute a risk for zoonotic infections. With respect to antimicrobial resistance, all described isolates were found to be susceptible to all antibiotics tested, and so far no data on the development of spontaneous resistance or the acquisition of resistance genes such the mecA/mecC cassette are available. In summary, general knowledge about this pathogen, specifically on the potential threat it may incur to human and animal health, is still very poor. In this review article, we compile the present state of scientific research, and identify the knowledge gaps that need to be filled in order to reliably assess S. schweitzeri as an organism with global One Health implications.

Antibody escape and global spread of SARS-CoV-2 lineage A.27.

In spring 2021, an increasing number of infections was observed caused by the hitherto rarely described SARS-CoV-2 variant A.27 in south-west Germany. From December 2020 to June 2021 this lineage has been detected in 31 countries. Phylogeographic analyses of A.27 sequences obtained from national and international databases reveal a global spread of this lineage through multiple introductions from its inferred origin in Western Africa. Variant A.27 is characterized by a mutational pattern in the spike gene that includes the L18F, L452R and N501Y spike amino acid substitutions found in various variants of concern but lacks the globally dominant D614G. Neutralization assays demonstrate an escape of A.27 from convalescent and vaccine-elicited antibody-mediated immunity. Moreover, the therapeutic monoclonal antibody Bamlanivimab and partially the REGN-COV2 cocktail fail to block infection by A.27. Our data emphasize the need for continued global monitoring of novel lineages because of the independent evolution of new escape mutations.

Implementation of Automated Blood Culture With Quality Assurance in a Resource-Limited Setting.

Background: Blood cultures (BC) have a high clinical relevance and are a priority specimen for surveillance of antimicrobial resistance. Manual BC are still most frequently used in resource-limited settings. Data on automated BC performance in Africa are scarce. We implemented automated BC at a surveillance site of the African Network for improved Diagnostics, Epidemiology and Management of Common Infectious Agents (ANDEMIA). Methods: Between June 2017 and January 2018, pairs of automated BC (BacT/ALERT®FA Plus) and manual BC (brain-heart infusion broth) were compared at a University hospital in Bouaké, Côte d'Ivoire. BC were inoculated each with a target blood volume of 10 ml from the same venipuncture. Automated BC were incubated for up to 5 days, manual BC for up to 10 days. Terminal subcultures were performed for manual BC only. The two systems were compared regarding yield, contamination, and turnaround time. For quality assurance, isolates were retested in a German routine microbiological laboratory. Results: BC sampling was increased from on average 24 BC to 63 BC per month. A total of 337 matched pairs of BC were included. Automated BC was positive in 36.5%, manual BC in 24.0% (p-value < 0.01), proportion of contamination was 47.9 and 43.8%, respectively (p-value = 1.0). Turnaround time of positive BC was shortened by 2.5 days with automated compared to manual BC (p < 0.01). Most common detected pathogens in both systems were Klebsiella spp. (26.0%) and Staphylococcus aureus (18.2%). Most contaminants were members of the skin flora. Retesting of 162 isolates was concordant in 79.6% on family level. Conclusions: Implementing automated BC in a resource-limited setting is possible and improves microbiological diagnostic performance. Automated BC increased yield and shortened turnaround times. Regular training and mentorship of clinicians has to be intensified to increase number and quality of BC. Pre-analytical training to improve diagnostic stewardship is essential when implementing a new microbiological method. Retesting highlighted that manual identification and antimicrobial susceptibility testing can be of good quality and sustainable. The implementation of automated tools should be decided individually according to economic considerations, number of samples, stable supply chain of consumables, and technical sustainability.

The African Network for Improved Diagnostics, Epidemiology and Management of common infectious Agents.

BACKGROUND: In sub-Saharan Africa, acute respiratory infections (ARI), acute gastrointestinal infections (GI) and acute febrile disease of unknown cause (AFDUC) have a large disease burden, especially among children, while respective aetiologies often remain unresolved. The need for robust infectious disease surveillance to detect emerging pathogens along with common human pathogens has been highlighted by the ongoing novel coronavirus disease 2019 (COVID-19) pandemic. The African Network for Improved Diagnostics, Epidemiology and Management of Common Infectious Agents (ANDEMIA) is a sentinel surveillance study on the aetiology and clinical characteristics of ARI, GI and AFDUC in sub-Saharan Africa. METHODS: ANDEMIA includes 12 urban and rural health care facilities in four African countries (Côte d'Ivoire, Burkina Faso, Democratic Republic of the Congo and Republic of South Africa). It was piloted in 2018 in Côte d'Ivoire and the initial phase will run from 2019 to 2021. Case definitions for ARI, GI and AFDUC were established, as well as syndrome-specific sampling algorithms including the collection of blood, naso- and oropharyngeal swabs and stool. Samples are tested using comprehensive diagnostic protocols, ranging from classic bacteriology and antimicrobial resistance screening to multiplex real-time polymerase chain reaction (PCR) systems and High Throughput Sequencing. In March 2020, PCR testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and analysis of full genomic information was included in the study. Standardised questionnaires collect relevant clinical, demographic, socio-economic and behavioural data for epidemiologic analyses. Controls are enrolled over a 12-month period for a nested case-control study. Data will be assessed descriptively and aetiologies will be evaluated using a latent class analysis among cases. Among cases and controls, an integrated analytic approach using logistic regression and Bayesian estimation will be employed to improve the assessment of aetiology and associated risk factors. DISCUSSION: ANDEMIA aims to expand our understanding of ARI, GI and AFDUC aetiologies in sub-Saharan Africa using a comprehensive laboratory diagnostics strategy. It will foster early detection of emerging threats and continued monitoring of important common pathogens. The network collaboration will be strengthened and site diagnostic capacities will be reinforced to improve quality management and patient care.

Primate phageomes are structured by superhost phylogeny and environment.

Humans harbor diverse communities of microorganisms, the majority of which are bacteria in the gastrointestinal tract. These gut bacterial communities in turn host diverse bacteriophage (hereafter phage) communities that have a major impact on their structure, function, and, ultimately, human health. However, the evolutionary and ecological origins of these human-associated phage communities are poorly understood. To address this question, we examined fecal phageomes of 23 wild nonhuman primate taxa, including multiple representatives of all the major primate radiations. We find relatives of the majority of human-associated phages in wild primates. Primate taxa have distinct phageome compositions that exhibit a clear phylosymbiotic signal, and phage-superhost codivergence is often detected for individual phages. Within species, neighboring social groups harbor compositionally and evolutionarily distinct phageomes, which are structured by superhost social behavior. Captive nonhuman primate phageome composition is intermediate between that of their wild counterparts and humans. Phage phylogenies reveal replacement of wild great ape-associated phages with human-associated ones in captivity and, surprisingly, show no signal for the persistence of wild-associated phages in captivity. Together, our results suggest that potentially labile primate-phage associations have persisted across millions of years of evolution. Across primates, these phylosymbiotic and sometimes codiverging phage communities are shaped by transmission between groupmates through grooming and are dramatically modified when primates are moved into captivity.

Pharyngeal Carriage of Beta-Haemolytic Streptococcus Species and Seroprevalence of Anti-Streptococcal Antibodies in Children in Bouaké, Côte d'Ivoire.

The pharynx of the child may serve as a reservoir of pathogenic bacteria, including beta-haemolytic group A streptococci (GAS), which can give rise to upper airway infections and post-streptococcal diseases. The objective of this study was to determine the prevalence of beta-haemolytic Streptococcus spp. in pharyngeal samples stemming from children aged 3-14 years in Bouaké, central Côte d'Ivoire. Oropharyngeal throat swabs for microbiological culture and venous blood samples to determine the seroprevalence of antistreptolysin O antibodies (ASO) were obtained from 400 children in March 2017. Identification was carried out using conventional bacteriological methods. Serogrouping was performed with a latex agglutination test, while an immunological agglutination assay was employed for ASO titres. The mean age of participating children was 9 years (standard deviation 2.5 years). In total, we detected 190 bacteria in culture, with 109 beta-haemolytic Streptococcus isolates, resulting in an oropharyngeal carriage rate of 27.2%. Group C streptococci accounted for 82.6% of all isolates, whereas GAS were rarely found (4.6%). The ASO seroprevalence was 17.3%. There was no correlation between serology and prevalence of streptococci (p = 0.722). In conclusion, there is a high pharyngeal carriage rate of non-GAS strains in children from Bouaké, warranting further investigation.

Serological evidence for human exposure to Bacillus cereus biovar anthracis in the villages around Taï National Park, Côte d'Ivoire.

Bacillus cereus biovar anthracis (Bcbva) is an untypical anthrax-causing pathogen responsible for high wildlife mortality in Taï National Park (TNP), Côte d'Ivoire. However, nothing is known about its effect on the rural population living in the region bordering TNP. Contact to bushmeat is a known risk factor for exposure to a variety of zoonotic pathogens, but no human infections with Bcbva were noted so far. Therefore, we performed a retrospective seroprevalence analysis with sera from 1,386 study volunteers. We used assays which detect antibodies against the protective antigen PA, which is synthesized by both Bcbva and classic B. anthracis, and against the recently described antigen pXO2-60, a 35-kDa protein only produced by Bcbva. We found a high seroprevalence (22.37%) of antibodies against PA, and approximately half of those sera (10.46%) were also positive for the Bcbva-specific antigen pXO2-60. All sera negative for PA were also negative for antibodies against pXO2-60, confirming specificity and suitability of the PA/pXO2-60 combined serological assay. The fact that a large fraction of sera was positive for PA but negative for pXO2-60 can most likely be explained by lower immunogenicity of pXO2-60, but exposure to classic B. anthracis cannot be excluded. As only Bcbva has been detected in the TNP area so far, exposure to Bcbva can be suspected from the presence of antibodies against PA alone. In a questionnaire, most study participants reported contact to bushmeat and livestock carcasses. Unfortunately, risk factor analysis indicated that neither animal contacts, sex, age, nor country of origin were significant predictors of Bcbva seroprevalence. Nevertheless, our study added to an assessment of the distribution of Bcbva and its impact on the human population, and our data can serve to raise awareness of anthrax in the affected regions.

Detection of possible spillover of a novel hantavirus in a Natal mastomys from Guinea.

To date, only two rodent-borne hantaviruses have been detected in sub-Saharan Africa. Here, we report the detection of a yet unknown hantavirus in a Natal mastomys (Mastomys natalensis) in Méliandou, Guinea, in 2014. The phylogenetic placement of this virus suggests that it might represent a cross-order spillover event from an unknown bat or eulipotyphlan host.

High prevalence of ESBL-producing Klebsiella pneumoniae in clinical samples from central Côte d'Ivoire.

OBJECTIVES: Infections caused by multidrug-resistant Enterobacterales pose a significant challenge to clinical patient care, particularly in resource-constrained settings where epidemiological data on antimicrobial resistance are scarce. The aim of this study was to determine the prevalence of extended spectrum beta-lactamase-(ESBL)-producing Klebsiella pneumoniae among clinical samples from a teaching hospital in Bouaké, central Côte d'Ivoire. METHODS: Clinical specimens were collected from sterile and non-sterile body sites and were subjected to microbiological diagnostics (April 2016-June 2017). The antimicrobial susceptibility patterns of K. pneumoniae were analysed using automated resistance testing and double-disk diffusion to test for ESBL production. Multiplex PCR was carried out to determine the presence of the resistance-conferring genes blaCTX-M, blaSHV and blaTEM. RESULTS: A total of 107 isolates were included, most of which were obtained from bloodstream (39%; n=42) and urinary tract infections (39%; n=42). Among all K. pneumoniae isolates, 84% (n=90) were ESBL producers, many of which were also not susceptible to sulfonamides (99%), quinolones (81%) and aminoglycosides (79%). The majority of ESBL-producing strains harboured all three investigated bla genes. CONCLUSION: The high prevalence of ESBL-producing K. pneumoniae in clinical isolates from Côte d'Ivoire calls for revised empirical treatment regimens in critically ill patients with suspected Gram-negative infections, and the establishment of antimicrobial resistance surveillance systems.

Highly diversified shrew hepatitis B viruses corroborate ancient origins and divergent infection patterns of mammalian hepadnaviruses.

Shrews, insectivorous small mammals, pertain to an ancient mammalian order. We screened 693 European and African shrews for hepatitis B virus (HBV) homologs to elucidate the enigmatic genealogy of HBV. Shrews host HBVs at low prevalence (2.5%) across a broad geographic and host range. The phylogenetically divergent shrew HBVs comprise separate species termed crowned shrew HBV (CSHBV) and musk shrew HBV (MSHBV), each containing distinct genotypes. Recombination events across host orders, evolutionary reconstructions, and antigenic divergence of shrew HBVs corroborated ancient origins of mammalian HBVs dating back about 80 million years. Resurrected CSHBV replicated in human hepatoma cells, but human- and tupaia-derived primary hepatocytes were resistant to hepatitis D viruses pseudotyped with CSHBV surface proteins. Functional characterization of the shrew sodium taurocholate cotransporting polypeptide (Ntcp), CSHBV/MSHBV surface peptide binding patterns, and infection experiments revealed lack of Ntcp-mediated entry of shrew HBV. Contrastingly, HBV entry was enabled by the shrew Ntcp. Shrew HBVs universally showed mutations in their genomic preCore domains impeding hepatitis B e antigen (HBeAg) production and resembling those observed in HBeAg-negative human HBV. Deep sequencing and in situ hybridization suggest that HBeAg-negative shrew HBVs cause intense hepatotropic monoinfections and low within-host genomic heterogeneity. Geographical clustering and low MSHBV/CSHBV-specific seroprevalence suggest focal transmission and high virulence of shrew HBVs. HBeAg negativity is thus an ancient HBV infection pattern, whereas Ntcp usage for entry is not evolutionarily conserved. Shrew infection models relying on CSHBV/MSHBV revertants and human HBV will allow comparative assessments of HBeAg-mediated HBV pathogenesis, entry, and species barriers.

Knowledge, attitudes, perception and behaviours of HIV/AIDS among end-cycle students in Cote d'Ivoire: Cross-sectional survey

In Cote d'Ivoire, the prevalence of HIV/AIDS has declined significantly in the last decade as a result ofpublic health actions. An assessment of knowledge, attitudes, perception and behaviours was carriedout to assess the outcome of the strategies for raising awareness and communicating with students about HIV/AIDS. A descriptive cross-sectional study was conducted in 2014 among students enrolled in third year at the university. An anonymous self-questionnaire including a consent form was provided. Mean scores were calculated from the items in the questionnaire to assess the level of knowledge, attitude, perception and behaviours of these students with regard to HIV/AIDS. The chi square test was used to compare the qualitative variables, and the quantitative variables were compared with the test of student. Among 561 students who participated in the study, 41.7, 26.7 and 31.6% were respectively registered in the sectors of human and social sciences (HSS), biosciences and health sciences. The mean age was 25.9 ± 3.4 years with a sex ratio of 1.3. The mean knowledge score of certain modes of transmission was 4.9 ± 0.36 out of 5 while that of condom positive perception was 6.4 ± 2.2 out of 12. This perception score was significantly higher in women than in men (6.1 vs. 6.9, p = 0.0001). The mean acceptance score was 7.3 ± 2.2 out of 10. The results of this work show good knowledge about HIV/AIDS among the students surveyed. However, the positive perception of the condom is far from being integrated in the student environment. This study also showed the persistence of HIV risk behaviour is out of sync with the level of Knowledge. It would be important to review marketing and communication strategies about HIV

Cytomegaloviruses in a Community of Wild Nonhuman Primates in Taï National Park, Côte D'Ivoire.

Cytomegaloviruses (CMVs) are known to infect many mammals, including a number of nonhuman primates (NHPs). However, most data available arose from studies led on captive individuals and little is known about CMV diversity in wild NHPs. Here, we analyzed a community of wild nonhuman primates (seven species) in Taï National Park (TNP), Côte d'Ivoire, with two PCR systems targeting betaherpesviruses. CMV DNA was detected in 17/87 primates (4/7 species). Six novel CMVs were identified in sooty mangabeys, Campbell's monkeys and Diana monkeys, respectively. In 3/17 positive individuals (from three NHP species), different CMVs were co-detected. A major part of the glycoprotein B coding sequences of the novel viruses was amplified and sequenced, and phylogenetic analyses were performed that included three previously discovered CMVs of western red colobus from TNP and published CMVs from other NHP species and geographic locations. We find that, despite this locally intensified sampling, NHP CMVs from TNP are completely host-specific, pinpointing the absence or rarity of cross-species transmission. We also show that on longer timescales the evolution of CMVs is characterized by frequent co-divergence with their hosts, although other processes, including lineage duplication and host switching, also have to be invoked to fully explain their evolutionary relationships.

A Cross-Sectional Serosurvey of Anti-Orthopoxvirus Antibodies in Central and Western Africa.

Since the eradication of smallpox and the subsequent discontinuation of the worldwide smallpox vaccination program, other Orthopoxviruses beside Variola virus have been increasingly representing a risk to human health. To investigate the extent of natural contact with Orthopoxviruses and possible demographic risk factors for such an exposure, we performed a cross-sectional serosurvey of anti-Orthopoxvirus IgG antibodies in West and Central Africa. To this end, people living in forest regions in Côte d'Ivoire (CIV, n = 737) and the Democratic Republic of the Congo (COD, n = 267) were assigned into groups according to their likely smallpox vaccination status. The overall prevalence of anti-Orthopoxvirus antibodies was 51% in CIV and 60% in COD. High rates of seropositivity among the vaccinated part of the population (80% in CIV; 96% COD) indicated a long-lasting post vaccination immune response. In non-vaccinated participants, seroprevalences of 19% (CIV) and 26% (COD) indicated regular contact with Orthopoxviruses. Multivariate logistic regression revealed that the antibody level in the vaccinated part of the population was higher in COD than in CIV, increased with age and was slightly higher in females than males. In the unvaccinated part of the population none of these factors influenced antibody level significantly. In conclusion, our results confirm expectedly high anti-Orthopoxvirus seroprevalences in previously smallpox-vaccinated people living in CIV and the COD but more unexpectedly imply regular contact with Orthopoxviruses both in Western and Central Africa, even in the absence of recognized outbreaks.

Epidemiology of paediatric meningitis in central Côte d'Ivoire after the implementation of Haemophilus influenzae type b vaccination.

Infectious meningitis accounts for enormous morbidity worldwide, but there is a paucity of data on its regional epidemiology in resource-constrained settings of sub-Saharan Africa. Here, we present a study on the aetiology of paediatric meningitis in central Côte d'Ivoire. Between June 2012 and December 2013, all cerebrospinal fluid (CSF) samples drawn at the University Teaching Hospital Bouaké were examined for the presence of bacterial and fungal pathogens. A causative agent was detected in 31 out of 833 CSF specimens (3.7%), with the most prevalent pathogens being Streptococcus pneumoniae (n=15) and Neisseria meningitidis (n=5). With the exception of neonates, these two bacteria were the most common agents in all age groups. Of note, only a single case of Haemophilus influenzae meningitis was detected. Hence, this study reports a considerable shift in the epidemiology of paediatric meningitis in central Côte d'Ivoire. Following the implementation of a nation-wide childhood vaccination programme against H. influenzae type b, this pathogen was much less frequently reported than in previous studies. The integration of specific vaccines against S. pneumoniae and N. meningitidis into the childhood vaccination programme in Côted'Ivoire holds promise to further reduce the burden due to infectious meningitis.

Bushmeat Hunting and Zoonotic Transmission of Simian T-Lymphotropic Virus 1 in Tropical West and Central Africa.

Simian T-lymphotropic virus 1 (STLV-1) enters human populations through contact with nonhuman primate (NHP) bushmeat. We tested whether differences in the extent of contact with STLV-1-infected NHP bushmeat foster regional differences in prevalence of human T-lymphotropic virus 1 (HTLV-1). Using serological and PCR assays, we screened humans and NHPs at two Sub-Saharan African sites where subsistence hunting was expected to be less (Taï region, Côte d'Ivoire [CIV]) or more (Bandundu region, Democratic Republic of the Congo [DRC]) developed. Only 0.7% of human participants were infected with HTLV-1 in CIV (n = 574), and 1.3% of humans were infected in DRC (n = 302). Two of the Ivorian human virus sequences were closely related to simian counterparts, indicating ongoing zoonotic transmission. Multivariate analysis of human demographic parameters and behavior confirmed that participants from CIV were less often exposed to NHPs than participants from DRC through direct contact, e.g., butchering. At the same time, numbers of STLV-1-infected NHPs were higher in CIV (39%; n = 111) than in DRC (23%; n = 39). We conclude that similar ultimate risks of zoonotic STLV-1 transmission-defined as the product of prevalence in local NHP and human rates of contact to fresh NHP carcasses-contribute to the observed comparable rates of HTLV-1 infection in humans in CIV and DRC. We found that young adult men and mature women are most likely exposed to NHPs at both sites. In view of the continued difficulties in controlling zoonotic disease outbreaks, the identification of such groups at high risk of NHP exposure may guide future prevention efforts.IMPORTANCE Multiple studies report a high risk for zoonotic transmission of blood-borne pathogens like retroviruses through contact with NHPs, and this risk seems to be particularly high in tropical Africa. Here, we reveal high levels of exposure to NHP bushmeat in two regions of Western and Central tropical Africa. We provide evidence for continued zoonotic origin of HTLV-1 in humans at CIV, and we found that young men and mature women represent risk groups for zoonotic transmission of pathogens from NHPs. Identifying such risk groups can contribute to mitigation of not only zoonotic STLV-1 transmission but also transmission of any blood-borne pathogen onto humans in Sub-Saharan Africa.

Seroprevalence of Cytomegalovirus Infection Among a Rural Population of Côte d'Ivoire.

Human cytomegalovirus (HCMV) is a betaherpesvirus that can be pathogenic to humans. In particular, immunocompromised patients can develop life-threatening symptoms. In the present study, HCMV seroprevalence was investigated in a rural population of Western Côte d'Ivoire. Plasma samples collected from 166 apparently healthy subjects living in 8 villages surrounding the Taï Forest National Park were tested for anti-HCMV immunoglobulin G and M antibody with two commercial enzyme-linked immunosorbent assays. Prevalence of anti-HCMV IgG and IgM antibody was 100% and 5.4%, respectively. Anti-HCMV IgM positive was 10.2% (5/49) of the children and adolescents and 3.4% (4/117) of the adults. This observed decrease of IgM seropositivity and the seroprevalence difference between males and females (3.8% vs. 6.1%) was not statistically significant. In plasma of one IgM-positive participant, a low CMV load was detected indicating low-level replication. A second IgM-positive participant showed signs of local CMV replication. The other seven IgM-positive plasma samples likely reacted nonspecifically or due to polyclonal stimulation. Taken together, the results indicate that HCMV infection is hyperendemic in Côte d'Ivoire.