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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 (r2 = 0.89; P < 0.001). Conclusion: Our results suggest that cheaper and open techniques such as Biocentric could be useful alternatives for HIV viral load follow-up quantification in resource limited settings like Cameroon; even with its high viral diversity. [ABSTRACT FROM AUTHOR]

Background: The outcome of CMV/HIV co-infection in infants treated early with combined antiretroviral therapy (cART) in resource-limited settings has not been described. We aimed to estimate the prevalence and identify factors associated with early CMV infection in HIV-infected and non-infected infants included in a study in Cameroon, and to compare HIV disease progression and survival after 1 year of early cART, following infants' CMV status.Methods: HIV-infected infants followed from birth or from HIV diagnosis before 7 months old and HIV-uninfected infants born to HIV-infected or uninfected mothers were tested for CMV at a median age of 4.0 months [Interquartile range (IQR): 3.4-4.9]. Multivariable logistic regression was performed to identify factors associated with CMV infection. Early cART was offered to HIV-infected infants: mortality, immunological and virological outcomes were assessed.Results: Three hundred and sixty-nine infants were tested. The proportion of infants infected with CMV at baseline was significantly higher in HIV-infected than in HIV-uninfected groups (58.9% (86/146) vs 30.0% (67/223), p < 0.001). At baseline, median CMV viral load was higher in HIV-infected (3.7 log copies/ml [IQR; 3.1-4.3]) than in HIV-uninfected infants (2.8 log copies [IQR; 2.1-3.4], p < 0.001). cART was initiated in 90% of HIV-infected infants (132/146) at a median age of 4.0 months (IQR; 3.2-5.9); in this sub-group CMV infection was independently associated with being followed from the time of HIV diagnosis rather than from birth (aOR = 3.1, 95%CI [1.2-8.0]), born to a non-single mother (aOR = 3.4[1.4-8.1]), and breastfeeding (aOR = 7.3 [2.7-19.4]). HIV-infected infants were retested after a median of 7.1 months [4.8-9.5]: CMV was undetectable in 37 of the 61 (60.7%) initially CMV-infected cases and became detectable in 8 of the 38 (21.1%) initially CMV-negative cases. After 1 year of cART, the probability of death (0.185 vs 0.203; p = 0.75), the proportion of cases with HIV RNA viral load <400 copies/ml (75.5% vs 61.5%; p = 0.17) and the mean CD4 percentage increase (10.97% vs 6.88%; p = 0.15) did not differ between CMV+ and CMV- infants.Conclusions: We observed a high prevalence of CMV infection among HIV-infected infants. Early initiation of cART may have limited the negative impact of CMV even in the absence of specific anti-CMV treatment. [ABSTRACT FROM AUTHOR]

Introduction: Replication of the human immunodeficiency virus involves an obligatory step of reverse transcription of the viral ribonucleic acid genome into a double-stranded deoxyribonucleic acid, and subsequent integration of the deoxyribonucleic acid into the human chromatin to form the proviral deoxyribonucleic acid. This proviral human immunodeficiency virus deoxyribonucleic acid is a critical marker for the diagnosis of acute infections, mother-to-child transmissions and for the confirmation of indeterminate serological reactions. We describe a case of a human immunodeficiency virus positive woman, naïve to antiretroviral treatment, who was persistently negative for human immunodeficiency virus proviral deoxyribonucleic acid polymerase chain reaction. This observation, to the best of our knowledge, is the first time that it has been described in Africa.Case Presentation: A 28-year-old Gabonese woman living in Cameroon requested a human immunodeficiency virus diagnosis in our laboratory. She had an unprotected heterosexual contact 6 months earlier while on vacation in Gabon. The request for a human immunodeficiency virus test was as a result of apprehensions developed after the exposure episode. Human immunodeficiency virus serological examinations were ambiguous and confirmatory tests (including human immunodeficiency virus proviral deoxyribonucleic acid polymerase chain reaction) were carried out. Apart from the human immunodeficiency virus proviral deoxyribonucleic acid polymerase chain reaction that was persistently negative, all other polymerase chain reactions carried out were positive. The deoxyribonucleic acid sequences have been submitted to the GenBank database with accession numbers: KC626022, KC626023 and KC626024 for the protease, reverse transcriptase and gp41 genes respectively.Conclusion: The persistently negative human immunodeficiency virus proviral deoxyribonucleic acid polymerase chain reaction in a person with a confirmed human immunodeficiency virus infection is of immense importance in the human immunodeficiency virus diagnostic field. This could highlight the fact that cases of false negative human immunodeficiency virus proviral deoxyribonucleic acid polymerase chain reactions exist especially with the high genetic variations observed with human immunodeficiency virus. The challenges presented by such false negative tests in the identification of acute infections, mother-to-child transmissions and the confirmation of indeterminate serological reactions are daunting. These data therefore would be invaluable especially to clinicians in Africa where non-B human immunodeficiency virus subtypes circulate. [ABSTRACT FROM AUTHOR]

Background: Viral load is still the marker of choice for monitoring adherence to combined antiretroviral therapy (cART) and confirming the success of HIV treatment. Unfortunately it is difficult to access in many resource-poor settings. We aimed to measure the performance of caregiver reporting adherence for detecting virological failure in routine practice during the first 2 years after cART initiation in infants.Methods: PEDIACAM is an ongoing prospective cohort study including HIV1-infected infants diagnosed before 7 months of age between November 2007 and October 2011 in Cameroon. Adherence was assessed using a questionnaire administered every 3 months from cART initiation; the HIV-RNA viral load was determined at the same visits. Virological failure was defined as having a viral load ≥ 1000 cp/mL at 3 and 12 months after cART initiation or having a viral load ≥ 400 cp/mL at 24 months after cART initiation. The performance of each current missed and cumulative missed dose defined according to adherence as reported by caregiver was assessed using the viral load as the gold standard.Results: cART was initiated at a median age of 4 months (IQR: 3-6) in the 167 infants included. The cumulative missed dose showed the best overall performance for detecting virological failure after 12 months of cART (AUC test, p = 0.005, LR + =4.4 and LR- = 0.4). Whatever the adherence reporting criterion, the negative predictive value was high (NPV ≥ 75%) 12 and 24 months after cART initiation, whereas the positive predictive value was low (PPV ≤ 50%).Conclusions: The adherence questionnaire administered by the health care provider to the infants' caregivers is not reliable for detecting virological failure in routine practice: its positive predictive value is low. However, the cumulative missed dose measurement may be a reliable predictor of virological success, particularly after 12 months of cART, given its high negative predictive value. [ABSTRACT FROM AUTHOR]

Background: Loss to follow-up (LTFU) is a cause of potential bias in clinical studies. Differing LTFU between study groups may affect internal validity and generalizability of the results. Understanding reasons for LTFU could help improve follow-up in clinical studies and thereby contribute to goals for prevention, treatment, or research being achieved. We explored factors associated with LTFU of mother-child pairs after inclusion in the ANRS 12140-Pediacam study. Methods: From November 2007 to October 2010, 4104 infants including 2053 born to HIV-infected mothers and 2051 born to HIV-uninfected mothers matched individually on gender and study site were enrolled during the first week of life in three referral hospitals in Cameroon and scheduled for visits at 6, 10 and 14 weeks of age. Visits were designated 1, 2 and 3, in chronological order, irrespective of the child's age at the time of the visit. Mother-child pairs were considered lost to follow-up if they never returned for a clinical visit within the first six months after inclusion. Uni- and multivariable logistic regression were adjusted on matching variables to identify factors associated with LTFU according to maternal HIV status. Results: LTFU among HIV-unexposed infants was four times higher than among HIV-exposed infants (36.7% vs 9.8%, p < 0.001). Emergency caesarean section (adjusted Odds Ratio (aOR) = 2.46 95% Confidence Interval (CI) [1.47-4.13]), young maternal age (aOR = 2.29, 95% CI [1.18-4.46]), and absence of antiretroviral treatment for prophylaxis (aOR = 3.45, 95% CI [2.30-5.19]) were independently associated with LTFU among HIV-exposed infants. Factors associated with LTFU among HIV-unexposed infants included young maternal age (aOR = 1.96, 95% CI [1.36-2.81]), low maternal education level (aOR = 2.77, 95% CI [1.95-3.95]) and housewife/unemployed mothers (aOR = 1.56, 95% CI [1.16-2.11]). Conclusion: Failure to return for at least one scheduled clinical visit is a problem especially among HIV-unexposed infants included in studies involving HIV-exposed infants. Factors associated with this type of LTFU included maternal characteristics, socio-economic status, quality of antenatal care and obstetrical context of delivery. Enhanced counselling in antenatal and intrapartum services is required for mothers at high risk of failure to return for follow-up visits. [ABSTRACT FROM AUTHOR]

Background: The placenta plays an important role in the control of in utero HIV-1 mother-to-child transmission (MTCT). Proinflammatory cytokines in the placental environment are particularly implicated in this control. We thus investigated the effect of TNF-α on HIV-1 expression in human placental tissues in vitro. Results: Human placental chorionic villi fragments were infected with varying doses of luciferase reporter HIV-1 pseudotypes with the R5, X4-Env or the vesicular stomatitis virus protein G (VSVG). Histocultures were then performed in the presence or absence of recombinant human TNF-α. Luciferase activity was measured at different time points in cell lysates or on whole fragments using ex vivo imaging systems. A significant increase in viral expression was detected in placental fragments infected with 0.2 ng of p24 antigen/fragment (P = 0.002) of VSV-G pseudotyped HIV-1 in the presence of TNF-α seen after 120 hours of culture. A time independent significant increase of viral expression by TNF-α was observed with higher doses of VSV-G pseudotyped HIV-1. When placental fragments were infected with R5-Env pseudotyped HIV-1, a low level of HIV expression at 168 hours of culture was detected for 3 of the 5 placentas tested, with no statistically significant enhancement by TNF-α. Infection with X4-Env pseudotyped HIV-1 did not lead to any detectable luciferase activity at any time point in the absence or in the presence of TNF-α. Conclusion: TNF-α in the placental environment increases HIV-1 expression and could facilitate MTCT of HIV-1, particularly in an inflammatory context. [ABSTRACT FROM AUTHOR]

An abstract of the article "Perinatal transmission of Cytomegalovirus (CMV) in children born to HIV positive and negative women in Cameroon," by Anfumbom Kfutwah and colleagues, is presented.

An abstract of the article "Why do HIV negative mothers refuse to participate in a clinical research involving HIV positive mothers in Cameroon?" by Mathurin Cyrille Tejiokem and colleagues, is presented.

Background Placental cytokines play vital roles in establishing and maintaining pregnancy as well as protecting the fetus from in utero infections. Previous studies have strongly suggested the implication of co-infections such as P. falciparum in the in utero MTCT of HIV-1. This study was designed to assess the impact of P. falciparum on the influence of HIV-1 infection on placental cytokine profile and the association of these profiles with clinical factors known to be related to HIV-1 MTCT. Materials and methods P. falciparum was tested in the peripheral and/or placental blood from 50 and 80 HIV-1 negative and positive women respectively. Cytokines (proteins) were quantified in the supernatants of 24 hours culture of placental explants by ELISA while cytokine mRNAs were quantified in placental tissue by real time PCR. Antibodies to the DBL3γ domain of PfEMP1 that binds P. falciparum infected red blood cells to placental CSA were titrated by ELISA in sera. The comparisons of the levels of cytokine proteins and mRNAs, as well as of anti-DBL3γ antibodies between HIV-1 negative and positive women who were either P. falciparum negative, or positive in the periphery or placenta, were tested through non-parametric tests, as well as the associations between cytokine profiles and clinical factors. Results Placental and peripheral P. falciparum infection was comparable in both HIV-1 negative and positive women (from 18 to 24%). Conversely P. falciparum parasitemia was significantly higher in the HIV-1 positive group. Large individual variations were observed in placental cytokine proteins and mRNA expression in each group. No significant differences were observed between placental cytokine median levels (protein and mRNA) in HIV-1 negative and positive women. However, among P. falciparum negative women, we observed significant differences in several cytokine median levels (TNF-α, IL-10, IL-16, IL-7, LIF, and RANTES) between HIV-1 negative and positive women. Median levels of antibodies to DBL3γ were significantly higher in the HIV-1 negative group (p=0.03) and was dependent of peripheral and placental P.falciparum infection. TNF-α among the HIV-1 positive women was the only cytokine associated with clinical parameters linked to HIV-1 MTCT (premature rupture of membranes, umber of pregnancies and parity; p≤0.04). Conclusions Altogether these results highlight the reciprocal influence of both infections at the materno-fetal interface that might have possible implications for in utero HIV-1 MTCT in areas where HIV-1 and P. falciparum co-circulate. [ABSTRACT FROM AUTHOR]

Background Since 2003 seven laboratories of the International Network of Pasteur Institutes have implemented HIV-1 genotypic drug resistance tools. These tools were then applied to study primary antiretroviral (ARV) resistance in drugnaïve HIV positive pregnant women living in central Africa (Cameroon, Central African Republic or CAR) and South-East Asia (Cambodia, Vietnam). Methods HIV-1 positive ARV naïve pregnant women who gave their written informed consent participated to the study. In addition to clinical examination, EDTA blood samples were collected for T-CD4 count, plasma HIV-RNA viral load determination and ARV genotypic resistance testing following the French ANRS AC11 guidelines for both reverse transcriptase and protease genes. HIV genetic sequences were analysed with the latest version of the ANRS, Stanford HIVdb and IAS algorithms. HIV-1 subtypes were determined by phylogenetic analysis and BLAST search. Statistical comparisons of the results were performed through the Fisher's exact test or Kruskall-wallis test, whenever appropriated. Results Overall, 362 women participated: 95 in Cameroon, 93 in CAR, 122 in Cambodia, and 52 in Vietnam. At inclusion, the median age was 26 years (IQR:22-30). For most of the women (94%), HIV status was known for less than a year and 31% were in their first pregnancy. The median CD4 counts was 358 cells/mm³ (IQR: 220-551). The median HIV-RNA viral load was 4.6 Log RNA copies/ml (IQR: 4-5) in Cameroon and CAR. Phylogenetic analysis revealed that 96% and 98% of viral sequences from Cambodia and Vietnam, respectively, belonged to the CRF01_AE subtype. In Cameroon, 60% of the samples clustered with CRF02_AG subtype, but 10 other subtypes were encountered. In CAR, 40% and 22% of samples belonged to CRF11 and A1 subtypes respectively. Seven strains of 362, 1.9%, (4 from Cambodia, 2 from Vietnam and 1 from Cameroon) harboured mutations associated to major ARV resistance in RT gene: 4 with V75M (resistance to D4T), 1 with the K101E (resistant to NVP and EFV) and the last one with the mutation L210W/T215S (weak resistance to AZT/D4T). In the protease gene, 3 strains (1 from Cameroon and 2 from Cambodia) bore N88 alone or associated to M46I, conferring resistance to IDV and NFV. Conclusion This four-sites study confirmed the high genetic diversity of HIV-1 circulating in Central Africa compared to the hegemony of CRF01_AE in South-East Asia. Drug resistance mutation survey revealed prevalence below 5% in this sentinel population, consistent with the recent introduction of ARV in these countries. [ABSTRACT FROM AUTHOR]

Background Malaria is endemic in countries of sub-Saharan Africa where there is also a high prevalence of HIV-1 infection, with pregnant women being the population most at risk to both infections. Epidemiological data and indirect evidence have established a link between placental malaria and an increased risk for HIV-1 mother-to-child transmission (MTCT), by unknown mechanisms. Material and methods The placenta-derived choriocarcinoma cell line BeWo and monocyte-derived macrophages (MDM) were infected with varying doses of luciferase reporter HIV-1 pseudo-typed with the vesicular stomatitis virus protein G. A recombinant DBL3γ domain, derived from a placental Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) adhesin domain (DBL3γ-732), that binds to chondroitin sulfate A (CSA) and a non-CSA-binding PfEMP1 adhesin domain, DBL1α-varO domain were used to stimulate infected cells. In some experiments, DBL3γ-732 was preincubated with the Fab fragment of a specific or an irrelevant monoclonal antibodies (mAb) that inhibits, or not, binding to CSA. TNF-α was measured in the culture supernatants and luciferase activity was quantified at different time points in cell lysates to evaluate viral replication. Results Addition of DBL3γ-732 to BeWo cells, led to a dose-dependent increase of HIV-1 replication of up to 400 times the control level in the absence of DBL3γ-732. This enhancement was specific since it was inhibited by Fab fragment of an anti- DBL3γ-732 monoclonal antibody but not by the Fab of an irrelevant mAb. In contrast, the addition of DBL1α-varO domain does not increase viral replication. In MDM which presents surface CSA, both DBL domains strongly inhibit viral replication. The effect of DBL3γ-732 on HIV-1 replication is most likely mediated by TNF-α as this cytokine is significantly increased by DBL3γ-732 binding to BeWo cells and MDM. Conclusions This study shows, for the first time, a direct link between a P. falciparum antigen and an increase of HIV-1 replication in placental cells in vitro. If this is occuring in vivo, the presence of both infections could lead to a higher risk of HIV-1 in utero transmission. These data underline the importance of efficient malaria prophylaxis and antiretroviral interventions for pregnant women in areas where HIV-1 and malaria co-circulate. [ABSTRACT FROM AUTHOR]

Background: Viral load is still the marker of choice for monitoring adherence to combined antiretroviral therapy (cART) and confirming the success of HIV treatment. Unfortunately it is difficult to access in many resource-poor settings. We aimed to measure the performance of caregiver reporting adherence for detecting virological failure in routine practice during the first 2 years after cART initiation in infants., Methods: PEDIACAM is an ongoing prospective cohort study including HIV1-infected infants diagnosed before 7 months of age between November 2007 and October 2011 in Cameroon. Adherence was assessed using a questionnaire administered every 3 months from cART initiation; the HIV-RNA viral load was determined at the same visits. Virological failure was defined as having a viral load ≥ 1000 cp/mL at 3 and 12 months after cART initiation or having a viral load ≥ 400 cp/mL at 24 months after cART initiation. The performance of each current missed and cumulative missed dose defined according to adherence as reported by caregiver was assessed using the viral load as the gold standard., Results: cART was initiated at a median age of 4 months (IQR: 3-6) in the 167 infants included. The cumulative missed dose showed the best overall performance for detecting virological failure after 12 months of cART (AUC test, p = 0.005, LR + =4.4 and LR- = 0.4). Whatever the adherence reporting criterion, the negative predictive value was high (NPV ≥ 75%) 12 and 24 months after cART initiation, whereas the positive predictive value was low (PPV ≤ 50%)., Conclusions: The adherence questionnaire administered by the health care provider to the infants' caregivers is not reliable for detecting virological failure in routine practice: its positive predictive value is low. However, the cumulative missed dose measurement may be a reliable predictor of virological success, particularly after 12 months of cART, given its high negative predictive value.

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.