Search

The reliable and timely detection of poliovirus infection through surveillance for acute flaccid paralysis (AFP), supplemented by environmental surveillance (ES) of sewage samples, is a critical component of the polio eradication programme. Since 1988, the number of polio cases caused by wild poliovirus (WPV) has decreased by >99.9%, and eradication of WPV serotypes 2 and 3 has been certified; only serotype 1 (WPV1) continues to circulate and transmission remains endemic in Afghanistan and Pakistan. In this surveillance update, we evaluated indicators of AFP in surveillance, ES for polioviruses and data on the performance of the Global Polio Laboratory Network (GPLN) provided by 28 priority countries for the programme during 2022-2023. No WPV1 cases have been detected outside those countries since August 2022, when importation into Malawi and Mozambique resulted in an outbreak during 2021-2022. During 2022-2023, 20 of 28 priority countries (71.4%) met national AFP surveillance indicator targets, and the number of ES sites increased. Low national rates of reported AFP cases in priority countries in 2023 might have been due to lags in surveillance reporting; substantial national and subnational AFP surveillance gaps persist. Maintaining high-quality surveillance is critical to achieving the goal of global polio eradication. Monitoring surveillance indicators is important to identifying gaps and guiding surveillance-strengthening activities, particularly in countries at high risk for poliovirus circulation. La detection fiable et rapide de l'infection a poliovirus au moyen de la surveillance de la paralysie flasque aigue (PFA), completee par une surveillance des echantillons d'eaux usees, est un element essentiel du programme d'eradication de la poliomyelite. Depuis 1988, le nombre de cas de poliomyelite dus au poliovirus sauvage (PVS) a diminue de >99,9% et l'eradication des serotypes 2 et 3 du PVS a ete certifiee; seul le serotype 1 du poliovirus sauvage (PVS1) continue de circuler et la transmission demeure endemique en Afghanistan et au Pakistan. Dans ce rapport faisant le point sur la surveillance, nous evaluons les indicateurs de la PFA a des fins de surveillance pour la recherche des poliovirus et les donnees relatives aux performances du Reseau mondial de laboratoires pour la poliomyelite (RMLP) communiquees par les 28 pays prioritaires pour le programme en 2022-2023. Aucun cas du au PVS1 n'a ete detecte en dehors de ces pays depuis aout 2022, apres une flambee epidemique en 2021-2022 due a l'importation du virus au Malawi et au Mozambique. En 2022-2023, 20 des 28 pays prioritaires (71,4 %) ont atteint les cibles des indicateurs de surveillance de la PFA, et le nombre de sites de surveillance environnementale a augmente. Le faible nombre de cas de PFA signales dans les pays prioritaires en 2023 pourrait etre du a des retards dans la communication des donnees issues de la surveillance; d'importantes lacunes en matiere de surveillance de la PFA a l'echelle nationale et infranationale persistent. Il est essentiel de maintenir une surveillance de qualite afin d'atteindre l'eradication de la poliomyelite a l'echelle mondiale. Un suivi des indicateurs de surveillance est egalement important pour identifier les lacunes et orienter les activites de surveillance, particulierement dans les pays oU il existe un risque eleve de circulation du poliovirus., Introduction Since the Global Polio Eradication Initiative (GPEI) was established in 1988, the number of WPV cases has decreased by >99.9%, and WPV serotypes 2 and 3 have been declared [...]

Since the Global Polio Eradication Initiative was established in 1988, the number of cases due to wild poliovirus (WPV) has decreased by >99.9%, and WPV serotypes 2 and 3 have [...]

Human Parechoviruses (HPeVs) have rarely been considered in the virological investigation of Acute Flacid Paralysis (AFP) cases in Africa, where enteric infections are very common. This study investigated the prevalence and genetic diversity of HPeV in 200 children aged ≤ 15 years with AFP in Cameroon from 2018 to 2019. HPeVs were detected in their faecal RNA using 5'-untranslated real-time RT-PCR. Detected HPeVs were typed by phylogenetic comparison with homologous sequences from homotypic reference strains. Overall, HPeV RNA was detected in 11.0% (22/200) of the 200 stool samples tested. Twelve HPeVs were successfully sequenced and reliably assigned to HPeV-A1, A4, A5, A10, A14, A15, A17 and A18 genotypes. Phylogenetic analyses revealed a high genetic variability among the studied HPeVs, as well as between the studied HPeVs and their previously reported counterparts from Cameroon in 2014. These findings suggest that different HPeV genotypes co-circulate in Cameroon without documented epidemics.

Genetic characterization of wild-type measles viruses (MeVs) is a critical component of the global measles surveillance programme. Sequence data can be used to map the transmission of MeVs by allowing [...]

The Central African Republic (CAR) is characterized by widespread HIV epidemic with notable prevalence and genetic diversity. We herein analysed the genetic diversity of atypical non‐M HIV‐1 strains. In‐house serotyping assays for variants of HIV‐1 (M, N, O, P) and HIV‐2 were used to test a biological collection of 6092 HIV‐seropositive blood samples collected between 2003 and 2014 at the Institut Pasteur de Bangui. Samples indicative of recombinant M/O groups, HIV‐2, or those that yield doubtful/negative results underwent further PCR tests and sequencing. We found six atypical HIV strains: specifically, three (0.05%) HIV‐1 group O strains (subtype H) detected in samples from 2005, 2008 and 2009, alongside three (0.05%) HIV‐2 strains (two group A and one group B) identified in samples from 2007 and 2009. HIV‐1/O strains showed a genetic link to Cameroon and Gabon strains. This study highlights the dominance of HIV‐1/M in the CAR's HIV epidemic over time and underscores the infrequent occurrence of HIV‐1 group O and HIV‐2 strains. These findings validate the efficacy of WHO‐recommended HIV testing protocols and emphasize the need for adaptive surveillance and management strategies to confront the complexities introduced by the genetic diversity of HIV strains. [ABSTRACT FROM AUTHOR]

Abstract Background In most studies, the virological response is assessed during the first two years of antiretroviral treatment initiated in HIV-infected infants. However, early initiation of antiretroviral therapy exposes infants to very long-lasting treatment. Moreover, maintaining viral suppression in children is difficult. We aimed to assess the virologic response and mortality in HIV-infected children after five years of early initiated antiretroviral treatment (ART) and identify factors associated with virologic success in Cameroon. Methods In the ANRS-12140 Pediacam cohort study, 2008–2013, Cameroon, we included all the 149 children who were still alive after two years of early ART. Virologic response was assessed after 5 years of treatment. The probability of maintaining virologic success between two and five years of ART was estimated using Kaplan-Meier curve. The immune status and mortality were also studied at five years after ART initiation. Factors associated with a viral load

The reliable and timely detection of poliovirus cases through surveillance for acute flaccid paralysis (AFP), supplemented by environmental surveillance of sewage samples, is a critical component of the polio eradication program. Since 1988, the number of polio cases caused by wild poliovirus (WPV) has declined by >99.9%, and eradication of WPV serotypes 2 and 3 has been certified; only serotype 1 (WPV1) continues to circulate, and transmission remains endemic in Afghanistan and Pakistan. This surveillance update evaluated indicators from AFP surveillance, environmental surveillance for polioviruses, and Global Polio Laboratory Network performance data provided by 28 priority countries for the program during 2022-2023. No WPV1 cases have been detected outside of Afghanistan and Pakistan since August 2022, when an importation into Malawi and Mozambique resulted in an outbreak during 2021-2022. During 2022-2023, among 28 priority countries, 20 (71.4%) met national AFP surveillance indicator targets, and the number of environmental surveillance sites increased. However, low national rates of reported AFP cases in priority countries in 2023 might have resulted from surveillance reporting lags; substantial national and subnational AFP surveillance gaps persist. Maintaining high-quality surveillance is critical to achieving the goal of global polio eradication. Monitoring surveillance indicators is important to identifying gaps and guiding surveillance-strengthening activities, particularly in countries at high risk for poliovirus circulation. [ABSTRACT FROM AUTHOR]

Abstract Background HIV infection in Cameroon is characterized by a great viral diversity with all HIV-1 groups (M, N, O, and P) and HIV-2 in circulation. HIV group determination is very important if tailored viral load analysis and treatments are to be applied. In our laboratory, HIV viral load is carried out using two platforms; Biocentric and Abbott depending on the HIV group identified. Biocentric which quantifies HIV-1 group M is a cheap and open system useful in resource limited settings. The objective of this study was to compare the viral load analyses of serologically group-indeterminate HIV samples using the two platforms with the view of reducing cost. Methods Consecutive samples received between March and May 2014, and between August and September 2014 in our laboratory for HIV viral load analysis were included. All these samples were analyzed for their HIV groups using an in-house ELISA serotyping test. All HIV-1 group M samples were quantified using the Biocentric test while all other known atypical samples (HIV-1 groups N, O and P) were analyzed using the Abbott technique. HIV group-indeterminate samples (by serotyping) were quantified with both techniques. Results Among the 6355 plasma samples received, HIV-1 group M was identified in 6026 (94.82%) cases; HIV-1 group O, in 20 (0.31%); HIV-1 group M + O, in 3 (0.05%) and HIV-2, in 3 (0.05%) case. HIV-group indeterminate samples represented about 4.76% (303/6355) and only 231 of them were available for analysis by Abbott Real-Time HIV-1 and Generic HIV Viral Load techniques. Results showed that 188 (81.39%) samples had undetectable viral load in both techniques. All the detectable samples showed high viral load, with a mean of 4.5 log copies/ml (range 2.1–6.5) for Abbott Real-Time and 4.5 log copies/ml (range 2–6.4) for Generic HIV Viral Load. The mean viral load difference between the two techniques was 0.03 log10 copies/ml and a good correlation was obtained (r 2 = 0.89; P

Unlike the pandemic form of HIV-1 (group M), group O viruses are endemic in west central Africa, especially in Cameroon. However, little is known about group O's genetic evolution, and why this highly divergent lineage has not become pandemic. Using a unique and large set of group O sequences from samples collected from 1987 to 2012, we find that this lineage has evolved in successive slow and fast phases of diversification, with a most recent common ancestor estimated to have existed around 1930 (1914-1944). The most rapid periods of diversification occurred in the 1950s and in the 1980s, and could be linked to favourable epidemiological contexts in Cameroon. Group O genetic diversity reflects this two-phase evolution, with two distinct populations potentially having different viral properties. The currently predominant viral population emerged in the 1980s, from an ancient population which had first developed in the 1950s, and is characterized by higher growth and evolutionary rates, and the natural presence of the Y181C resistance mutation, thought to confer a phenotypic advantage. Our findings show that although this evolutionary pattern is specific to HIV-1 group O, it paralleled the early spread of HIV-1 group M in the Democratic Republic of Congo. Both viral lineages are likely to have benefited from similar epidemiological contexts. The relative role of virological and social factors in the distinct epidemic histories of HIV-1 group O and M needs to be reassessed.

BACKGROUND: The consequences of maternal HIV infection for fetal growth are controversial. Here, we estimated the frequency of small for gestational age and gender (SGAG) among neonates born to HIV-infected or uninfected mothers and assessed the contribution, if any, of maternal HIV to the risk of SGAG. METHODS: The data used were obtained from the ANRS-Pediacam cohort in Cameroon. Pairs of newborns, one to a HIV-infected mother and the other to an uninfected mother, were identified during the first week of life, and matched on gender and recruitment site from 2007-2010. SGAG was defined in line with international recommendations as a birth weight Z-score adjusted for gestational age at delivery and gender more than two standard deviations below the mean (-2SD). Considering the matched design, logistic regression modeling was adjusted on site and gender to explore the effect of perinatal HIV exposure on SGAG. RESULTS: Among the 4104 mother-infant pairs originally enrolled, no data on birth weight and/or gestational age were available for 108; also, 259 were twins and were excluded. Of the remaining 3737 mother-infant pairs, the frequency of SGAG was 5.3% (95%CI: 4.6-6.0), and was significantly higher among HIV-infected infants (22.4% vs. 6.3%; p

BACKGROUND: Early infant diagnosis (EID) of HIV is a key-point for the implementation of early HAART, associated with lower mortality in HIV-infected infants. We evaluated the EID process of HIV according to national recommendations, in urban areas of Cameroon. METHODS/FINDINGS: The ANRS12140-PEDIACAM study is a multisite cohort in which infants born to HIV-infected mothers were included before the 8(th) day of life and followed. Collection of samples for HIV DNA/RNA-PCR was planned at 6 weeks together with routine vaccination. The HIV test result was expected to be available at 10 weeks. A positive or indeterminate test result was confirmed by a second test on a different sample. Systematic HAART was offered to HIV-infected infants identified. The EID process was considered complete if infants were tested and HIV results provided to mothers/family before 7 months of age. During 2007-2009, 1587 mother-infant pairs were included in three referral hospitals; most infants (n = 1423, 89.7%) were tested for HIV, at a median age of 1.5 months (IQR, 1.4-1.6). Among them, 51 (3.6%) were HIV-infected. Overall, 1331 (83.9%) completed the process by returning for the result before 7 months (median age: 2.5 months (IQR, 2.4-3.0)). Incomplete process, that is test not performed, or result of test not provided or provided late to the family, was independently associated with late HIV diagnosis during pregnancy (adjusted odds ratio (aOR) = 1.8, 95%CI: 1.1 to 2.9, p = 0.01), absence of PMTCT prophylaxis (aOR = 2.4, 95%CI: 1.4 to 4.3, p = 0.002), and emergency caesarean section (aOR = 2.5, 95%CI: 1.5 to 4.3, p = 0.001). CONCLUSIONS: In urban areas of Cameroon, HIV-infected women diagnosed sufficiently early during pregnancy opt to benefit from EID whatever their socio-economic, marital or disclosure status. Reduction of non optimal diagnosis process should focus on women with late HIV diagnosis during pregnancy especially if they did not receive any PMTCT, or if complications occurred at delivery.

BACKGROUND: Multidrug antiretroviral (ARV) regimens including HAART and short-course dual antiretroviral (sc-dARV) regimens were introduced in 2004 to improve Prevention of Mother-to-Child Transmission (PMTCT) in Cameroon. We assessed the effectiveness of these regimens from 6-10 weeks and 12 months of age, respectively. METHODOLOGY/FINDINGS: We conducted a retrospective cohort study covering the period from October 2004 to March 2008 in a reference hospital in Cameroon. HIV-positive pregnant women with CD4 < or = 350 cells/mm(3) received first-line HAART [regimen 1] while the others received ARV prophylaxis including sc-dARV or single dose nevirapine (sd-NVP). Sc-dARV included at least two drugs according to different gestational ages: zidovudine (ZDV) from 28-32 weeks plus sd-NVP [regimen 2], ZDV and lamuvidine (3TC) from 33-36 weeks plus sd-NVP [regimen 3]. When gestational age was > or = 37 weeks, women received sd-NVP during labour [regimen 4]. Infants received sd-NVP plus ZDV and 3TC for 7 days or 30 days. Early diagnosis (6-10 weeks) was done, using b-DNA and subsequently RT-PCR. We determined early MTCT rate and associated risk factors using logistic regression. The 12-month HIV-free survival was assessed using Cox regression. Among 418 mothers, 335 (80%) received multidrug ARV regimens (1, 2, and 3) and MTCT rate with multidrug regimens was 6.6% [95%CI: 4.3-9.6] at 6 weeks, without any significant difference between regimens. Duration of mother's ARV regimen < 4 weeks [OR = 4.7, 95%CI: 1.3-17.6], mother's CD4 < 350 cells/mm(3) [OR = 6.4, 95%CI: 1.8-22.5] and low birth weight [OR = 4.0, 95%CI: 1.4-11.3] were associated with early MTCT. By 12 months, mixed feeding [HR = 8.7, 95%CI: 3.6-20.6], prematurity [HR = 2.3, 95%CI: 1.2-4.3] and low birth weight were associated with children's risk of progressing to infection or death. CONCLUSIONS: Multidrug ARV regimens for PMTCT are feasible and effective in routine reference hospital. Early initiation of ARV during pregnancy and proper obstetrical care are essential to improve PMTCT.

BACKGROUND:Placental cytokines play crucial roles in the establishment and maintenance of pregnancy as well as protecting the foetus from infections. Previous studies have suggested the implication of infections such as P. falciparum and HIV in the stimulation of placental cytokines. This study assessed the impact of P. falciparum on placental cytokine profiles between HIV-1 positive and negative women. MATERIALS AND METHODS:P. falciparum infection was checked in peripheral and placental blood of HIV-1 negative and positive women by the thick blood smear test. Cytokines proteins and messenger RNAs were quantified by ELISA and real time PCR, respectively. Non-parametric tests were used for statistical analyses. RESULTS:Placental and peripheral P. falciparum infections were not significantly associated with HIV-1 infection (OR: 1.4; 95% confidence interval (95%CI): 0.5-4.2; p = 0.50 and OR: 0.6; 95%CI: 0.3-1.4; p = 0.26, respectively). Conversely, placental P. falciparum parasitemia was significantly higher in the HIV-1 positive group (p = 0.04). We observed an increase of TNF-alpha mRNA median levels (p = 0.02) and a trend towards a decrease of IL-10 mRNA (p = 0.07) in placenta from HIV-1 positive women compared to the HIV negative ones leading to a median TNF-alpha/IL-10 mRNA ratio significantly higher among HIV-1 positive than among HIV-1 negative placenta (p = 0.004; 1.5 and 0.8, respectively). Significant decrease in median secreted cytokine levels were observed in placenta from HIV-1 positive women as compared to the HIV negative however these results are somewhat indicative since it appears that differences in cytokine levels (protein or mRNA) between HIV-1 positive and negative women depend greatly on P.falciparum infection. Within the HIV-1 positive group, TNF-alpha was the only cytokine significantly associated with clinical parameters linked with HIV-1 MTCT such as premature rupture of membranes, CD4 T-cell number, plasma viral load and delay of NVP intake before delivery. CONCLUSIONS:These results show that P. falciparum infection profoundly modifies the placenta cytokine environment and acts as a confounding factor, masking the impact of HIV-1 in co-infected women. This interplay between the two infections might have implications in the in utero MTCT of HIV-1 in areas where HIV-1 and P. falciparum co-circulate.

Herpesvirus infection of placenta may be harmful in pregnancy leading to disorders in fetal growth, premature delivery, miscarriage, or major congenital abnormalities. Although a correlation between human herpesvirus 8 (HHV-8) infection and abortion or low birth weight in children has been suggested, and rare cases of in utero or perinatal HHV-8 transmission have been documented, no direct evidence of HHV-8 infection of placenta has yet been reported. The aim of this study was to evaluate the in vitro and in vivo susceptibility of placental cells to HHV-8 infection. Short-term infection assays were performed on placental chorionic villi isolated from term placentae. Qualitative and quantitative HHV-8 detection were performed by PCR and real-time PCR, and HHV-8 proteins were analyzed by immunohistochemistry. Term placenta samples from HHV-8-seropositive women were analyzed for the presence of HHV-8 DNA and antigens. In vitro infected histocultures showed increasing amounts of HHV-8 DNA in tissues and supernatants; cyto- and syncitiotrophoblasts, as well as endothelial cells, expressed latent and lytic viral antigens. Increased apoptotic phenomena were visualized by the terminal deoxynucleotidyl transferase-mediated deoxyuridine nick end-labeling method in infected histocultures. Ex vivo, HHV-8 DNA and a latent viral antigen were detected in placenta samples from HHV-8-seropositive women. These findings demonstrate that HHV-8, like other human herpesviruses, may infect placental cells in vitro and in vivo, thus providing evidence that this phenomenon might influence vertical transmission and pregnancy outcome in HHV-8-infected women.

BACKGROUND: The Expanded Program on Immunization (EPI) is the most cost-effective measures to control vaccine-preventable diseases. Currently, the EPI schedule is similar for HIV-infected children; the introduction of antiretroviral therapy (ART) should considerably prolong their life expectancy. METHODS AND PRINCIPAL FINDINGS: To evaluate the persistence of antibodies to the EPI vaccines in HIV-infected and HIV-exposed uninfected children who previously received these vaccines in routine clinical practice, we conducted a cross-sectional study of children, aged 18 to 36 months, born to HIV-infected mothers and living in Central Africa. We tested blood samples for antibodies to the combined diphtheria, tetanus, and whole-cell pertussis (DTwP), the measles and the oral polio (OPV) vaccines. We enrolled 51 HIV-infected children of whom 33 were receiving ART, and 78 HIV-uninfected children born to HIV-infected women. A lower proportion of HIV-infected children than uninfected children had antibodies to the tested antigens with the exception of the OPV types 1 and 2. This difference was substantial for the measles vaccine (20% of the HIV-infected children and 56% of the HIV-exposed uninfected children, p

Abstract Background Transmission of hepatitis B virus (HBV) from HBV-positive mothers to their infants is common and usually occurs when the mother is hepatitis B e antigen (HBeAg) positive and/or has a high HBV DNA load. In this study, we determined the prevalence of hepatitis B surface antigen (HBsAg) and HBeAg among pregnant women with known HIV status. Findings A total of 650 pregnant women with a mean age of 26.2 years including 301 HIV-positives and 349 HIV-negatives were screened for HBsAg (Monolisa AgHBs Plus Biorad, France). Among the HBsAg-positives, HBeAg and anti-HBe were tested (Monolisa Ag HBe Plus Biorad, France). Overall, 51 (7.85%) were positive for HBsAg. The prevalence of HBsAg was not statistically different between HIV-positive and HIV-negative pregnant women [28/301 (9.3%) vs 23/349 (6.59%); p = 0.2]. None of the 45 HBsAg-positive samples was reactive for HBeAg. Conclusions Our study indicates a high prevalence of HBsAg with very low proportion of HBeAg in Cameroonian pregnant women. Since perinatal transmission of HBV is mostly effective when the mother is also HBeAg-positive, our data could suggest that perinatal transmissions play a minor role in HBV prevalence in Cameroon. In line with previous African studies, these findings further suggests that horizontal transmission could be the most common mechanism of HBV infections in Cameroon.