13 research outputs found

    Prevalence of human enteroviruses among apparently healthy nursery school children in Accra

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    Introduction: Human enteroviruses are common in children causing asymptomatic infections ranging  from mild to severe illnesses. In Ghana, information on the prevalence of non-polio enterovirus causing  acute flaccid paralysis is available but data on surveillance of these viruses in school children is scanty. Here, the prevalence of human enteroviruses among apparently healthy children in selected school in Accra was studied.Methods: Stool samples from 273 apparently healthy children less than eight years of age in 9 selected nursery schools were collected between December 2010 and March 2011and processed for human  enteroviruses on L20B, RD and Hep-2 cell lines. Positive Isolates were characterized by microneutralisation assay with antisera pools from RIVM, the Netherlands according to standard  methods recommended by WHO. Results: Of the 273 samples processed, 66 (24.2%) non-polio enteroviruses were isolated. More growth  was seen on Hep-2C (46%) only than RD (18%) only and on both cell lines (34%). No growth was seen on  L20B even after blind passage. Excretion of non-polio enteroviruses was found in all the schools with  majority in BD school. Serotyping of the isolates yielded predominantly Coxsackie B viruses followed by echoviruses 13 and 7. More than half of the isolates could not be typed by the antisera pools.Conclusion: The study detected 13 different serotypes of non-polio enteroviruses in circulation but no poliovirus was found. BD school was found to have the highest prevalence of NPEV. Complete  identification through molecular methods is essential to establish the full range of NPEVs in circulation in these schools.Key words: Non-polio enterovirus, apparently healthy, school children, Accra

    Respiratory syncytial virus genotypes circulating in urban Ghana: february to

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    Abstract Introduction: Respiratory syncytial virus (RSV) is the major cause of acute lower respiratory tract infection (ALRI) in young children. RSV strain

    Respiratory syncytial virus genotypes circulating in urban Ghana: february to november 2006

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    Introduction: Respiratory syncytial virus (RSV) is the major cause of acute lower respiratory tract  infection (ALRI) in young children. RSV strains have been divided into 2 major antigenic groups (A and B), which are further divided into several genotypes, but very little is known about its circulating genotypes in Ghana. This study characterized RSV genotypes detected in children with ALRI in Accra between  February and November 2006. Methods: Nasopharyngeal aspirates (NPA) were obtained from children diagnosed with ALRI between  February and November 2006. The NPA were screened for RSV using a nested multiplex reverse  transcriptase polymerase chain reaction (RT-PCR) method for genotyping RSV. Viral RNA was extracted from the NPA using guanidinium isothiocyanate method and purified with an RNAID commercial kit.  Care-givers gave their consent prior to specimen collection. Administered questionnaires captured  information on patient demographic and clinical history. Results: A total of 53 children were enrolled in the study with a male to female ratio of 3:1. Of the 53 NPA  analyzed, 60.4% (32/53) were positive for RSV. Subsequent genotypic analysis showed that 72% (23/32) of the 60.4% RSV infections were RSV B only and 28% (9/32) were co-infections of both RSV A and B. Children between the ages of 2 - 12 months were the most affected age group per an RSV infection rate of 37.5% (12/32). No significant difference was detected in the recovery rate of ALRI (98.1%) and RSV (96.9%) positive patients from the infection. One patient died resulting in a mortality rate of 3.1%. Bronchopneumonia (20 out of 32 cases) was the major diagnosis on admission. RSV infection was  seasonal dependent, described by 2 peaks in October and April-May.Conclusion: Both RSV A and RSV B genotypes co-circulated during the study period with RSV B  predominating. RSV may possibly be the main pathogen of lower respiratory tract illness during  epidemics in the wet seasons. Genotyping by the multiplex RT-PCR is one of the first attempts at  molecular diagnosis of RSV infection in Ghana.Key words: Respiratory syncytial viruses, lower respiratory tract infections, multiplex RT-PC

    Global respiratory syncytial virus–related infant community deaths

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    Background Respiratory syncytial virus (RSV) is a leading cause of pediatric death, with >99% of mortality occurring in low- and lower middle-income countries. At least half of RSV-related deaths are estimated to occur in the community, but clinical characteristics of this group of children remain poorly characterized. Methods The RSV Global Online Mortality Database (RSV GOLD), a global registry of under-5 children who have died with RSV-related illness, describes clinical characteristics of children dying of RSV through global data sharing. RSV GOLD acts as a collaborative platform for global deaths, including community mortality studies described in this supplement. We aimed to compare the age distribution of infant deaths <6 months occurring in the community with in-hospital. Results We studied 829 RSV-related deaths <1 year of age from 38 developing countries, including 166 community deaths from 12 countries. There were 629 deaths that occurred <6 months, of which 156 (25%) occurred in the community. Among infants who died before 6 months of age, median age at death in the community (1.5 months; IQR: 0.8−3.3) was lower than in-hospital (2.4 months; IQR: 1.5−4.0; P < .0001). The proportion of neonatal deaths was higher in the community (29%, 46/156) than in-hospital (12%, 57/473, P < 0.0001). Conclusions We observed that children in the community die at a younger age. We expect that maternal vaccination or immunoprophylaxis against RSV will have a larger impact on RSV-related mortality in the community than in-hospital. This case series of RSV-related community deaths, made possible through global data sharing, allowed us to assess the potential impact of future RSV vaccines

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    The significance of human respiratory syncytial virus (HRSV) in children from Ghana with acute lower respiratory tract infection: A molecular epidemiological analysis, 2006 and 2013-2014

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    Background: Acute lower respiratory tract infection (ALRI) is a leading cause of childhood morbidity and mortality in developing countries. Globally, human respiratory syncytial virus (HRSV) is the most common pathogen of ALRI in infants and children. However, age-stratified HRSV disease burden data are largely absent from Africa, which is a key gap in informing an evidence-based recommendation for the introduction of an HRSV vaccine by the WHO. Methods: This study investigated the presence of HRSV in respiratory specimens from 552 children <5 years old with ALRI from Accra, Ghana in 2006 and 2013–2014 by real-time PCR. Of HRSV-positive samples the second hypervariable region of the viral G protein gene was sequenced and analyzed for phylogeny, characteristic amino acid substitutions, and potential glycosylation patterns. Further, HRSV infections have been characterized by age, symptoms and timely occurrence. Results: HRSV was observed in 23% (127/552) of the children with ALRI, with the highest incidence in infants younger than one year (33%, 97/295, p = 0.013). Within the observed seasonal circulation time of HRSV from June (mid-wet season) to December (beginning of the dry season) the incidence of ALRI due to HRSV was as high as 46% (125/273). HRSV disease was significantly associated with (broncho-) pneumonia, bronchiolitis, LRTI, and difficulty in breathing. Phylogenetic characterization of HRSV strains from Ghana identified the circulation of the currently worldwide prevailing genotypes ON1 and BA9, and shows evidence of an independent molecular evolution of ON1 and BA9 strains in Ghana resulting in potentially new subgenotypes within ON1 and BA9, provisionally named ON1.5, ON1.6, and BA9-IV. Conclusion: This study addresses important knowledge gaps in the forefront of introducing the HRSV vaccine by providing information on the molecular evolution and incidence of HRSV in Accra (Ghana, Africa).Peer Reviewe

    Poliovirus antibody levels and lameness among individuals in three regions of Ghana

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    Introduction Ghana recorded the last case of poliomyelitis caused by wild poliovirus in 2008 and the country was declared polio-free in 2015. Polio-neutralizing-antibody levels in the population of three geographically representative regions of Ghana was determined, to identify possible immunity gaps. Methods Cross-sectional, hospital (1–70 years old) and school (primary, 1–15 years old)-based studies were undertaken in three regions in 2016. Individuals who visited the three teaching hospitals of the regions and were referred for haematology investigations were invited to participate in our study. Neutralizing-antibody titers to polio serotypes P1, P2, and P3 were assayed by WHO-standards. Antibody titers of ≥8 were considered protective. In the school lameness survey, clinical and epidemiological data were obtained from parents and their lamed children. Bivariate and multivariate analyses were conducted on subject characteristics, to assess potential factors for failure to seroconvert. P-values < 0.05 were considered statistically significant. Results Neutralizing-antibodies against poliovirus types 1, 2 and 3 were detected in 86% (264/307), 84% (258/307) and 75% (230/307) of the samples, respectively. Overall, 60.1% (185/307) were seropositive for the three polio serotypes and 2.9% (9/307) were seronegative. Polio neutralizing-antibodies (P1and P2) decreased with age (p < .001). Low seroprevalence of polio-neutralizing-antibodies was significantly associated with low school attendance of mothers (p < .001). Prevalence of residual paralysis was <1.0/1,000 among the school children. Conclusion Our study population is moderately protected against the three poliovirus serotypes. However, immunity appears to be lower with a higher age and low mother’s education. This may suggest the need for young-adult booster-dose to minimize the risk of wild poliovirus infection

    Emergence of HIV-1 drug resistance mutations in mothers on treatment with a history of prophylaxis in Ghana

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    Abstract Background Antiretrovirals have been available in Ghana since 2003 for HIV-1 positive pregnant women for prevention of mother-to-child transmission (PMTCT). Suboptimal responses to treatment observed post-PMTCT interventions necessitated the need to investigate the profile of viral mutations generated. This study investigated HIV-1 drug resistance profiles in mothers in selected centres in Ghana on treatment with a history of prophylaxis. Methods Genotypic Drug Resistance Testing for HIV-1 was carried out. Subtyping was done by phylogenetic analysis and Stanford HIV Database programme was used for drug resistance analysis and interpretation. To compare the significance between the different groups and the emergence of drug resistance mutations, p values were used. Results Participants who had prophylaxis before treatment, those who had treatment without prophylaxis and those yet to initiate PMTCT showed 32% (8), 5% (3) and 15% (4) HIV-1 drug resistance associated mutations respectively. The differences were significant with p value < 0.05. Resistance Associated Mutations (RAMs) were seen in 14 participants (35%) to nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs). The most common NRTI mutation found was M184 V; K103 N and A98G were the most common NNRTI mutations seen. Thymidine Analogue Mutations (TAMs) such as M41 L, K70R and T215Y were found in all the groups; the most common of the TAMs found were M41 L and T215Y. Majority of the subtypes were CRF02_AG (82%). Conclusion In Ghana initiation of uninterrupted treatment upon diagnosis, coupled with drug resistance testing, would produce a better treatment outcome for HIV-1 positive pregnant women

    Detection of vaccine-derived poliovirus circulation by environmental surveillance in the absence of clinical cases

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    Background On August 25, 2019, the Noguchi Memorial Institute for Medical Research notified the confirmation of a circulating-vaccine-derived poliovirus type-2 (cVDPV2) from the Agbogbloshie environmental surveillance (AES) site, in the Greater Accra Region. A field investigation of the outbreak was conducted to describe the results of epidemiological and laboratory investigations, and control efforts. Methods We conducted a descriptive investigation, records review, and active-case-search. Caregivers were interviewed on the vaccination status of their children; knowledge, attitude, and practices on polio prevention; water, sanitation and hygiene practices, and health-seeking behaviors. Stool from healthy children <5 y and sewage samples were taken for laboratory diagnosis. Results cVDPV2 genetically similar to the cVDPV2 diagnosed recently in the Northern Region of Ghana and Nigeria was identified. 2019 half-year coverage of OPV and IPV was 22%. Fully immunized children were 49% (29/59). Most health workers (70%) had a fair knowledge of polio and acute flaccid paralysis (AFP). Forty-six percent of care-givers admitted to using the large drain linked to the site where the cVDPV2 was isolated as their place of convenience and disposing of the fecal matter of their children. No AFP case was identified. Stool samples from 40 healthy children yielded non-polio enteroviruses while 75% (3/4) of the additional sewage samples yielded cVDPV2. Conclusion cVDPV2 was isolated from the AES site. No AFP or poliovirus was identified from healthy children. There is a need to improve health workers’ knowledge on AFP and to address the dire sanitation conditions in the Agbogbloshie market and its environs
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