Public health physician and pediatrician with with more than 25 years experience in clinical medicine and Public health, interested in mother and child health and HIV.
Central Africa is considered to be an area of high endemic hepatitis C infection. To determine th... more Central Africa is considered to be an area of high endemic hepatitis C infection. To determine the prevalence of anti-HCV antibodies, HCV RNA, and the genotype distribution in Cameroon, 1,494 pregnant women attending antenatal care units in Yaounde, Cameroon were screened for HCV infection. Anti-HCV antibodies were detected with a 3rd generation ELISA (Monolisa anti-HCV plus version 2, BioRad, Richmond, CA). All anti-HCV antibody-positive sera were then tested with another 3rd generation ELISA (AxSYM) HCV version 3, Abbott Laboratories, Abbott Park, IL) and subsequently for HCV RNA (Amplicor HCV, Roche Diagnostics, Basel, Switzerland). Genotype was determined by phylogenetic analysis of the NS5b gene. Seventy-three pregnant women were found to be anti-HCV antibody positive by the first ELISA, but only 28 were anti-HCV positive by both ELISA. The prevalence of anti-HCV antibodies was thus 1.9% (28/1,494) (95% CI: 1.3-2.7%). 21/28 (75%) of the positive samples by both ELISA were HCV RNA positive. The 45 samples that were HCV antibody negative by the second ELISA were also HCV RNA negative. The HCV subtypes identified were 1a (24%), 2f (38%) and 4f (38%). In contrast to previous studies, anti-HCV antibodies were rare among pregnant women in Cameroon. The percentage of HCV seropositive pregnant women who had circulating HCV RNA was similar to that observed in Europe. Several HCV genotypes were found in Cameroon.
Objectives: The number needed to test (NNT) to identify a child infected with HIV remains high in... more Objectives: The number needed to test (NNT) to identify a child infected with HIV remains high in the context of the implementation of the blanket provider-initiated testing and counselling (bPITC) strategy. This study assessed the predictors of HIV seropositivity among outpatient children/adolescents (6 weeks-19 years) in Cameroon. This information is needed to improve the yield of bPITC and reduce the current gap in pediatric and adolescent ART coverage in this country and beyond. Study design: Cross-sectional study conducted in 3 hospitals in Cameroon. Methods: Through biological parents and guardians we systematically invited children and adolescents visiting the outpatient departments for any reason to test for HIV (bPITC) in a 6-month period. Children and adolescents were tested for HIV following the national guidelines and the predictors of HIV seropositivity were assessed using multivariate logistic regression at 5% significant level. Results: A total of 2729 eligible children/adolescents were enrolled. Among these, 90.3% (2465/2729) were tested for HIV. Out of these, 1.6% (40/2465) tested HIV-positive, corresponding to a NNT of 62. In multivariate analysis, HIV seropositivity was 2.5, 3.3, and 5 times more likely to be reported among children/adolescents of the female sex [aOR ¼ 0.4 (0.2-0.8), p ¼ 0.008]; whose fathers had no formal school education [aOR ¼ 0.3 (0.1-0.6), p ¼ 0.004] and those whose mothers had died [aOR ¼ 0.2 (0.0-0.9), p ¼ 0.041], respectively. Conclusions: Focusing HIV testing among female children/adolescents, whose fathers had no education level and whose mothers had died could reduce the NNT, improve the yield of bPITC and increase the pediatric and adolescent ART coverage.
Sensitive assays are needed for detection of residual HIV in patients with undetectable plasma vi... more Sensitive assays are needed for detection of residual HIV in patients with undetectable plasma viral loads to determine if eradication strategies are effective. The gold standard quantitative viral outgrowth assay (QVOA) underestimates the magnitude of the viral reservoir, while sensitive PCR-based assays lack the ability to distinguish replication competent from defective virus. We sought to determine whether xenograft of leukocytes from HIV-1 infected patients with undetectable plasma viral loads into severely immunocompromised mice would result in viral amplification and measurable viral loads within the aberrant murine host. Methods: We evaluated whether xenograft of 1) peripheral blood mononuclear cells (PBMCs) from five HIV-1' patients on suppressive antiretroviral therapy (ART), 2) PBMCs or purified resting CD4' T cells from 5 HIV-1' elite suppressors (ES), or 3) PBMCs from a Simian Immunodeficiency Virus (SIV)' pigtailed macaque on suppressive ART, all with undetectable plasma viral loads, into NOD. Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) mice resulted in viral amplification in the mouse. Successful xenograft of mice was confirmed by flow cytometry. Human CD8' T cells were depleted in humanized mice with depleting antibody, and CD4' T cells were activated in a subset of mice with activating anti-CD3. Plasma viral loads in xenografted mice were quantified using qRT-PCR, and compared to plasma viral load and QVOA results from the human or macaque donor. Results: With this murine viral outgrowth assay (MVOA), we amplified HIV-1 from all 10 HIV' subjects with undetectable plasma viral load, including an ES from whom we were unable to recover virus by QVOA. We detected HIV in mice an average of 20 days after xenograft with PBMCs from patients on suppressive ART, and an average of 28 days after xenograft with PBMCs or resting CD4' T cells from ES. For two of the mice xenografted with CD4' T cells from ES, we detected HIV only after activation with anti-CD3. We similarly detected SIV in macaquized mice by seven days post-xenograft. The MVOA has the potential to serve as a powerful tool to identify residual HIV-1 in patients with undetectable viral loads, such as those who have undergone promising cure therapies.
JAIDS Journal of Acquired Immune Deficiency Syndromes, 2017
While the Interagency Task Team on the Prevention and Treatment of HIV Infection in Pregnant Wome... more While the Interagency Task Team on the Prevention and Treatment of HIV Infection in Pregnant Women, Mothers, and Children (IATT) partnership existed before the Global Plan Towards the Elimination of New HIV Infections Among Children by 2015 and Keeping Their Mothers Alive (Global Plan), its reconfiguration was critical to coordinating provision of technical assistance that positively influenced country decision-making and program performance. This article describes how the Global Plan anchored the work of the IATT and, in turn, how the IATT's technical assistance helped to accelerate achievement of the Global Plan targets and milestones. The technical assistance that will be discussed addressed a broad range of priority actions and milestones described in the Global Plan: (1) planning for and implementing Option B+; (2) strengthening monitoring and evaluation systems; (3) translating evidence into action and advocacy; and (4) promoting community engagement. This article also reviews the ongoing challenges and opportunities of providing technical assistance in a rapidly evolving environment that calls for ever more flexible and contextualized responses. The effectiveness of technical assistance facilitated by the IATT was defined by its timeliness, evidence base, and unique global perspective that built on the competencies of its partners and promoted synergies across program areas. Reaching the final goal of eliminating vertical transmission of HIV infection and achieving an AIDS-free generation in countries with the highest HIV burden requires that the IATT partnership and technical assistance remain responsive to country-specific needs while aligning with the current programmatic reality and new global goals such as the Sustainable Development Goals and 90-90-90 targets.
The WHO recommendations for the immunization of children infected with human immunodeficiency vir... more The WHO recommendations for the immunization of children infected with human immunodeficiency virus (HIV) differ slightly from the guidelines for uninfected children. The introduction of antiretroviral therapy for HIV-infected infants should considerably prolong their life expectancy. The question of the response to the whole-cell pertussis (wP) vaccine should now be addressed, particularly in countries in which pertussis remains endemic. To evaluate the persistence of antibodies to the wP vaccine in HIV-infected and uninfected children who had previously received this vaccine 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 Cameroon or the Central African Republic. We tested blood samples for antibodies to the wP vaccine and for antibodies to diphtheria and tetanus toxoids (D and T, respectively) in the context of the use of a combined DTwP vaccine. We enrolled 50 HIV-infected children an...
Background. The Expanded Program on Immunization (EPI) is the most cost-effective measures to con... more 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 ha...
Background: Mother to child transmission (MTCT) of HIV constitutes a major source of new pediatri... more Background: Mother to child transmission (MTCT) of HIV constitutes a major source of new pediatric infections in Cameroon. Objective: The aim of this implementation research was to assess outcomes and effectiveness of providing lifelong antiretroviral therapy (ART) for HIV-positive pregnant and breastfeeding women (Option B+). Methods: From October 2013 to July 2014, HIV-positive pregnant and breastfeeding women, not on antiretroviral (ARV) prophylaxis and ART, were recruited from 22 purposefully selected health facilities in the Northwest and Southwest regions for a prospective, observational cohort evaluation. Option B+ was offered to participants and outcome indicators were measured. Results: Out of 680 women eligible for this assessment, 669 (98%) were initiated on Option B+. Retention-in-care was 90% (95% CI, 87.85-92.61) and 79% (95% CI, 75.20-81.88), and loss to follow up (LTFU) was 7% (95% CI: 4.95-8.90) and 15% (95% CI: 12.06-17.56) at 6 and 12 months respectively. Maternal mortality at 12 months after ART initiation was 2% (13). As of March 2015, 538 HIV exposed infants
The aim of the study was to evaluate the feasibility of infant feeding options of HIV positive mo... more The aim of the study was to evaluate the feasibility of infant feeding options of HIV positive mothers in urban areas (especially compliance to artificial feeding choices), before the implementation of the infant feeding interventions and procurement of breastmilksubstitutes. We conducted a survey among seropositive women diagnosed during pregnancy and counselled for infant feeding options. At 6 months post delivery an interview was done. 47 mothers were included. Bromocriptine was prescribed to all the mothers who opted for artificial feeding from birth. After counselling 85% of women opted for exclusive artificial feeding of whom 83% mothers practised this option since birth. For those who opted for replacement feeding The main given reason for infant feeding choice was related to medical or nurses advices. Overall 36% [CI 95%, 22-50] of the mothers who opted for artificial milk faced difficulties to afford supplies during the 6 months, leading into an early introduction of paps. Clinical mastitis were mentioned by all those mothers who breastfed. Infant feeding choices were related to the level of education (X2 = 24.10, P = 0.002). Artificial feeding under recovery of cost seems feasible in urban areas in Cameroon and can be facilitate by the administration of antilacteal drugs. More adequate support must be provided for the mother who breastfeed in order to prevent and to treat mastitis. Additional training for counselling in HIV and infant feeding options is recommended for health workers.
Central Africa is considered to be an area of high endemic hepatitis C infection. To determine th... more Central Africa is considered to be an area of high endemic hepatitis C infection. To determine the prevalence of anti-HCV antibodies, HCV RNA, and the genotype distribution in Cameroon, 1,494 pregnant women attending antenatal care units in Yaounde, Cameroon were screened for HCV infection. Anti-HCV antibodies were detected with a 3rd generation ELISA (Monolisa anti-HCV plus version 2, BioRad, Richmond, CA). All anti-HCV antibody-positive sera were then tested with another 3rd generation ELISA (AxSYM) HCV version 3, Abbott Laboratories, Abbott Park, IL) and subsequently for HCV RNA (Amplicor HCV, Roche Diagnostics, Basel, Switzerland). Genotype was determined by phylogenetic analysis of the NS5b gene. Seventy-three pregnant women were found to be anti-HCV antibody positive by the first ELISA, but only 28 were anti-HCV positive by both ELISA. The prevalence of anti-HCV antibodies was thus 1.9% (28/1,494) (95% CI: 1.3-2.7%). 21/28 (75%) of the positive samples by both ELISA were HCV RNA positive. The 45 samples that were HCV antibody negative by the second ELISA were also HCV RNA negative. The HCV subtypes identified were 1a (24%), 2f (38%) and 4f (38%). In contrast to previous studies, anti-HCV antibodies were rare among pregnant women in Cameroon. The percentage of HCV seropositive pregnant women who had circulating HCV RNA was similar to that observed in Europe. Several HCV genotypes were found in Cameroon.
The American Journal of Tropical Medicine and Hygiene, Aug 1, 2005
To assess mother-to-child transmission (MTCT) of hepatitis C virus (HCV) in Cameroon, 5,008 pregn... more To assess mother-to-child transmission (MTCT) of hepatitis C virus (HCV) in Cameroon, 5,008 pregnant women were screened for HCV antibodies. Eighty-nine (1.8%) were HCV-antibody (HCV-Ab) positive. Among these, 7 (7.9%) were HBsAg positive, 6 (6.7%) HIV-positive, and one (1.1%) was co-infected by both hepatitis B virus (HBV) and HIV. Sixty-eight (76%) out of 89 HCV-Ab positive pregnant women were HCV-RNA positive. The HCV genotype determination indicated the predominance of genotype 4 (45.3%), followed by the genotypes 1 (28.1%) and 2 (26.6%). The mean HCV-RNA levels of 41 women at the time of delivery was 4.8 (range 0.06-34.7) × 10 6 RNA copies/mL. Finally, 35 women delivered 36 live children. None of those screened at 6 weeks and 6 months of age were HCV-RNA positive. The failure to detect HCV vertical transmission suggests that the mother-to-child transmission (MTCT) is not a major route of HCV transmission in Cameroon.
Lettre des orateurs de sessions de communications orales en partenariat CP6. Sessions de communic... more Lettre des orateurs de sessions de communications orales en partenariat CP6. Sessions de communications orales en partenariat avec le R6seau International des Instituts Pasteur (RIIP) Th~me : Le R~seau International des Instituts Pasteur : son r61e dans le suivi d'interventions th6rapeutiques et vaccinales dans les pays du Sud
The American journal of tropical medicine and hygiene, 2005
To assess mother-to-child transmission (MTCT) of hepatitis C virus (HCV) in Cameroon, 5,008 pregn... more To assess mother-to-child transmission (MTCT) of hepatitis C virus (HCV) in Cameroon, 5,008 pregnant women were screened for HCV antibodies. Eighty-nine (1.8%) were HCV-antibody (HCV-Ab) positive. Among these, 7 (7.9%) were HBsAg positive, 6 (6.7%) HIV-positive, and one (1.1%) was co-infected by both hepatitis B virus (HBV) and HIV. Sixty-eight (76%) out of 89 HCV-Ab positive pregnant women were HCV-RNA positive. The HCV genotype determination indicated the predominance of genotype 4 (45.3%), followed by the genotypes 1 (28.1%) and 2 (26.6%). The mean HCV-RNA levels of 41 women at the time of delivery was 4.8 (range 0.06-34.7) x 10(6) RNA copies/mL. Finally, 35 women delivered 36 live children. None of those screened at 6 weeks and 6 months of age were HCV-RNA positive. The failure to detect HCV vertical transmission suggests that the mother-to-child transmission (MTCT) is not a major route of HCV transmission in Cameroon.
Background: efforts to scale-up HIV treatment in high burden countries have resulted in wider acc... more Background: efforts to scale-up HIV treatment in high burden countries have resulted in wider access to care, improved survival and decreased morbidity for HIV-infected children. the country of Rwanda has made significant achievements in expanding coverage of pediatric HIV services. Methods: We describe the extent of and factors associated with mortality and lost to follow-up (LtF) in children (<15 years) enrolled in HIV care at 39 ICAp-supported facilities across Rwanda from 2004 to 2010 by antiretroviral treatment (ARt) status. We estimated the 1-year cumulative incidence of death and LtF among all children enrolled in care (pre-ARt) and children on ARt. survival analysis was used to evaluate factors associated with death and LtF in both groups. Results: Between January 2004 and June 2010, 3244 children with a median age of 5.7 years (interquartile range 2.8-9.6) enrolled in HIV care. one-year cumulative incidence for death and LtF among pre-ARt children was 4% (95% confidence interval [CI]: 3-5%) and 5% (95% CI: 4-6%), respectively. overall, 2035 (63%) children initiated ARt, median age 6.3 years (interquartile range 3.3-10.4): 1-year Kaplan-Meier estimates of death and LtF were 3% (95% CI: 3-4%) and 1% (95% CI: 1-2%), respectively. Factors associated with an increased hazard for death among pre-ARt children included being <18 months old versus ≥5 years (adjusted sub hazard ratio [asHR] = 4.4, 95% CI: 2.9-6.8) and World Health organization stage IV versus I (asHR = 4.1, 95% CI: 2.0-8.4), whereas children entering care through prevention of mother-to-child transmission had lower hazard than those from voluntary counseling and testing (asHR = 0.50, 95% CI: 0.25-1.0). Markers of advanced disease, including severe immunosuppression (asHR = 0.25, 95% CI: 0.12-0.54), and enrollment in care in rural versus urban clinics (asHR = 0.71, 95% CI: 0.53-0.97) were protective against LtF. For children on ARt, factors associated with hazard of death included younger age (adjusted hazard ratio [aHR] <18 months versus ≥5 years = 2.1, 95% CI: 1.3-3.6), severe malnutrition versus not malnourished (aHR = 3.2, 95% CI: 1.3-8.1), advanced World Health organization stage (aHR IV versus I = 9.8, 95% CI: 3.5-27.4) and severe immunodeficiency versus no evidence (aHR = 2.3, 95% CI: 1.7-3.3). No associations were observed with LtF among children on ARt.
The aim of the study was to evaluate the feasibility of infant feeding options of HIV positive mo... more The aim of the study was to evaluate the feasibility of infant feeding options of HIV positive mothers in urban areas (especially compliance to artificial feeding choices), before the implementation of the infant feeding interventions and procurement of breastmilksubstitutes. We conducted a survey among seropositive women diagnosed during pregnancy and counselled for infant feeding options. At 6 months post delivery an interview was done. 47 mothers were included. Bromocriptine was prescribed to all the mothers who opted for artificial feeding from birth. After counselling 85% of women opted for exclusive artificial feeding of whom 83% mothers practised this option since birth. For those who opted for replacement feeding The main given reason for infant feeding choice was related to medical or nurses advices. Overall 36% [CI 95%, 22-50] of the mothers who opted for artificial milk faced difficulties to afford supplies during the 6 months, leading into an early introduction of paps. Clinical mastitis were mentioned by all those mothers who breastfed. Infant feeding choices were related to the level of education (X2 = 24.10, P = 0.002). Artificial feeding under recovery of cost seems feasible in urban areas in Cameroon and can be facilitate by the administration of antilacteal drugs. More adequate support must be provided for the mother who breastfeed in order to prevent and to treat mastitis. Additional training for counselling in HIV and infant feeding options is recommended for health workers.
Central Africa is considered to be an area of high endemic hepatitis C infection. To determine th... more Central Africa is considered to be an area of high endemic hepatitis C infection. To determine the prevalence of anti-HCV antibodies, HCV RNA, and the genotype distribution in Cameroon, 1,494 pregnant women attending antenatal care units in Yaounde, Cameroon were screened for HCV infection. Anti-HCV antibodies were detected with a 3rd generation ELISA (Monolisa anti-HCV plus version 2, BioRad, Richmond, CA). All anti-HCV antibody-positive sera were then tested with another 3rd generation ELISA (AxSYM) HCV version 3, Abbott Laboratories, Abbott Park, IL) and subsequently for HCV RNA (Amplicor HCV, Roche Diagnostics, Basel, Switzerland). Genotype was determined by phylogenetic analysis of the NS5b gene. Seventy-three pregnant women were found to be anti-HCV antibody positive by the first ELISA, but only 28 were anti-HCV positive by both ELISA. The prevalence of anti-HCV antibodies was thus 1.9% (28/1,494) (95% CI: 1.3-2.7%). 21/28 (75%) of the positive samples by both ELISA were HCV RNA positive. The 45 samples that were HCV antibody negative by the second ELISA were also HCV RNA negative. The HCV subtypes identified were 1a (24%), 2f (38%) and 4f (38%). In contrast to previous studies, anti-HCV antibodies were rare among pregnant women in Cameroon. The percentage of HCV seropositive pregnant women who had circulating HCV RNA was similar to that observed in Europe. Several HCV genotypes were found in Cameroon.
Central Africa is considered to be an area of high endemic hepatitis C infection. To determine th... more Central Africa is considered to be an area of high endemic hepatitis C infection. To determine the prevalence of anti-HCV antibodies, HCV RNA, and the genotype distribution in Cameroon, 1,494 pregnant women attending antenatal care units in Yaounde, Cameroon were screened for HCV infection. Anti-HCV antibodies were detected with a 3rd generation ELISA (Monolisa anti-HCV plus version 2, BioRad, Richmond, CA). All anti-HCV antibody-positive sera were then tested with another 3rd generation ELISA (AxSYM) HCV version 3, Abbott Laboratories, Abbott Park, IL) and subsequently for HCV RNA (Amplicor HCV, Roche Diagnostics, Basel, Switzerland). Genotype was determined by phylogenetic analysis of the NS5b gene. Seventy-three pregnant women were found to be anti-HCV antibody positive by the first ELISA, but only 28 were anti-HCV positive by both ELISA. The prevalence of anti-HCV antibodies was thus 1.9% (28/1,494) (95% CI: 1.3-2.7%). 21/28 (75%) of the positive samples by both ELISA were HCV RNA positive. The 45 samples that were HCV antibody negative by the second ELISA were also HCV RNA negative. The HCV subtypes identified were 1a (24%), 2f (38%) and 4f (38%). In contrast to previous studies, anti-HCV antibodies were rare among pregnant women in Cameroon. The percentage of HCV seropositive pregnant women who had circulating HCV RNA was similar to that observed in Europe. Several HCV genotypes were found in Cameroon.
Objectives: The number needed to test (NNT) to identify a child infected with HIV remains high in... more Objectives: The number needed to test (NNT) to identify a child infected with HIV remains high in the context of the implementation of the blanket provider-initiated testing and counselling (bPITC) strategy. This study assessed the predictors of HIV seropositivity among outpatient children/adolescents (6 weeks-19 years) in Cameroon. This information is needed to improve the yield of bPITC and reduce the current gap in pediatric and adolescent ART coverage in this country and beyond. Study design: Cross-sectional study conducted in 3 hospitals in Cameroon. Methods: Through biological parents and guardians we systematically invited children and adolescents visiting the outpatient departments for any reason to test for HIV (bPITC) in a 6-month period. Children and adolescents were tested for HIV following the national guidelines and the predictors of HIV seropositivity were assessed using multivariate logistic regression at 5% significant level. Results: A total of 2729 eligible children/adolescents were enrolled. Among these, 90.3% (2465/2729) were tested for HIV. Out of these, 1.6% (40/2465) tested HIV-positive, corresponding to a NNT of 62. In multivariate analysis, HIV seropositivity was 2.5, 3.3, and 5 times more likely to be reported among children/adolescents of the female sex [aOR ¼ 0.4 (0.2-0.8), p ¼ 0.008]; whose fathers had no formal school education [aOR ¼ 0.3 (0.1-0.6), p ¼ 0.004] and those whose mothers had died [aOR ¼ 0.2 (0.0-0.9), p ¼ 0.041], respectively. Conclusions: Focusing HIV testing among female children/adolescents, whose fathers had no education level and whose mothers had died could reduce the NNT, improve the yield of bPITC and increase the pediatric and adolescent ART coverage.
Sensitive assays are needed for detection of residual HIV in patients with undetectable plasma vi... more Sensitive assays are needed for detection of residual HIV in patients with undetectable plasma viral loads to determine if eradication strategies are effective. The gold standard quantitative viral outgrowth assay (QVOA) underestimates the magnitude of the viral reservoir, while sensitive PCR-based assays lack the ability to distinguish replication competent from defective virus. We sought to determine whether xenograft of leukocytes from HIV-1 infected patients with undetectable plasma viral loads into severely immunocompromised mice would result in viral amplification and measurable viral loads within the aberrant murine host. Methods: We evaluated whether xenograft of 1) peripheral blood mononuclear cells (PBMCs) from five HIV-1' patients on suppressive antiretroviral therapy (ART), 2) PBMCs or purified resting CD4' T cells from 5 HIV-1' elite suppressors (ES), or 3) PBMCs from a Simian Immunodeficiency Virus (SIV)' pigtailed macaque on suppressive ART, all with undetectable plasma viral loads, into NOD. Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) mice resulted in viral amplification in the mouse. Successful xenograft of mice was confirmed by flow cytometry. Human CD8' T cells were depleted in humanized mice with depleting antibody, and CD4' T cells were activated in a subset of mice with activating anti-CD3. Plasma viral loads in xenografted mice were quantified using qRT-PCR, and compared to plasma viral load and QVOA results from the human or macaque donor. Results: With this murine viral outgrowth assay (MVOA), we amplified HIV-1 from all 10 HIV' subjects with undetectable plasma viral load, including an ES from whom we were unable to recover virus by QVOA. We detected HIV in mice an average of 20 days after xenograft with PBMCs from patients on suppressive ART, and an average of 28 days after xenograft with PBMCs or resting CD4' T cells from ES. For two of the mice xenografted with CD4' T cells from ES, we detected HIV only after activation with anti-CD3. We similarly detected SIV in macaquized mice by seven days post-xenograft. The MVOA has the potential to serve as a powerful tool to identify residual HIV-1 in patients with undetectable viral loads, such as those who have undergone promising cure therapies.
JAIDS Journal of Acquired Immune Deficiency Syndromes, 2017
While the Interagency Task Team on the Prevention and Treatment of HIV Infection in Pregnant Wome... more While the Interagency Task Team on the Prevention and Treatment of HIV Infection in Pregnant Women, Mothers, and Children (IATT) partnership existed before the Global Plan Towards the Elimination of New HIV Infections Among Children by 2015 and Keeping Their Mothers Alive (Global Plan), its reconfiguration was critical to coordinating provision of technical assistance that positively influenced country decision-making and program performance. This article describes how the Global Plan anchored the work of the IATT and, in turn, how the IATT's technical assistance helped to accelerate achievement of the Global Plan targets and milestones. The technical assistance that will be discussed addressed a broad range of priority actions and milestones described in the Global Plan: (1) planning for and implementing Option B+; (2) strengthening monitoring and evaluation systems; (3) translating evidence into action and advocacy; and (4) promoting community engagement. This article also reviews the ongoing challenges and opportunities of providing technical assistance in a rapidly evolving environment that calls for ever more flexible and contextualized responses. The effectiveness of technical assistance facilitated by the IATT was defined by its timeliness, evidence base, and unique global perspective that built on the competencies of its partners and promoted synergies across program areas. Reaching the final goal of eliminating vertical transmission of HIV infection and achieving an AIDS-free generation in countries with the highest HIV burden requires that the IATT partnership and technical assistance remain responsive to country-specific needs while aligning with the current programmatic reality and new global goals such as the Sustainable Development Goals and 90-90-90 targets.
The WHO recommendations for the immunization of children infected with human immunodeficiency vir... more The WHO recommendations for the immunization of children infected with human immunodeficiency virus (HIV) differ slightly from the guidelines for uninfected children. The introduction of antiretroviral therapy for HIV-infected infants should considerably prolong their life expectancy. The question of the response to the whole-cell pertussis (wP) vaccine should now be addressed, particularly in countries in which pertussis remains endemic. To evaluate the persistence of antibodies to the wP vaccine in HIV-infected and uninfected children who had previously received this vaccine 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 Cameroon or the Central African Republic. We tested blood samples for antibodies to the wP vaccine and for antibodies to diphtheria and tetanus toxoids (D and T, respectively) in the context of the use of a combined DTwP vaccine. We enrolled 50 HIV-infected children an...
Background. The Expanded Program on Immunization (EPI) is the most cost-effective measures to con... more 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 ha...
Background: Mother to child transmission (MTCT) of HIV constitutes a major source of new pediatri... more Background: Mother to child transmission (MTCT) of HIV constitutes a major source of new pediatric infections in Cameroon. Objective: The aim of this implementation research was to assess outcomes and effectiveness of providing lifelong antiretroviral therapy (ART) for HIV-positive pregnant and breastfeeding women (Option B+). Methods: From October 2013 to July 2014, HIV-positive pregnant and breastfeeding women, not on antiretroviral (ARV) prophylaxis and ART, were recruited from 22 purposefully selected health facilities in the Northwest and Southwest regions for a prospective, observational cohort evaluation. Option B+ was offered to participants and outcome indicators were measured. Results: Out of 680 women eligible for this assessment, 669 (98%) were initiated on Option B+. Retention-in-care was 90% (95% CI, 87.85-92.61) and 79% (95% CI, 75.20-81.88), and loss to follow up (LTFU) was 7% (95% CI: 4.95-8.90) and 15% (95% CI: 12.06-17.56) at 6 and 12 months respectively. Maternal mortality at 12 months after ART initiation was 2% (13). As of March 2015, 538 HIV exposed infants
The aim of the study was to evaluate the feasibility of infant feeding options of HIV positive mo... more The aim of the study was to evaluate the feasibility of infant feeding options of HIV positive mothers in urban areas (especially compliance to artificial feeding choices), before the implementation of the infant feeding interventions and procurement of breastmilksubstitutes. We conducted a survey among seropositive women diagnosed during pregnancy and counselled for infant feeding options. At 6 months post delivery an interview was done. 47 mothers were included. Bromocriptine was prescribed to all the mothers who opted for artificial feeding from birth. After counselling 85% of women opted for exclusive artificial feeding of whom 83% mothers practised this option since birth. For those who opted for replacement feeding The main given reason for infant feeding choice was related to medical or nurses advices. Overall 36% [CI 95%, 22-50] of the mothers who opted for artificial milk faced difficulties to afford supplies during the 6 months, leading into an early introduction of paps. Clinical mastitis were mentioned by all those mothers who breastfed. Infant feeding choices were related to the level of education (X2 = 24.10, P = 0.002). Artificial feeding under recovery of cost seems feasible in urban areas in Cameroon and can be facilitate by the administration of antilacteal drugs. More adequate support must be provided for the mother who breastfeed in order to prevent and to treat mastitis. Additional training for counselling in HIV and infant feeding options is recommended for health workers.
Central Africa is considered to be an area of high endemic hepatitis C infection. To determine th... more Central Africa is considered to be an area of high endemic hepatitis C infection. To determine the prevalence of anti-HCV antibodies, HCV RNA, and the genotype distribution in Cameroon, 1,494 pregnant women attending antenatal care units in Yaounde, Cameroon were screened for HCV infection. Anti-HCV antibodies were detected with a 3rd generation ELISA (Monolisa anti-HCV plus version 2, BioRad, Richmond, CA). All anti-HCV antibody-positive sera were then tested with another 3rd generation ELISA (AxSYM) HCV version 3, Abbott Laboratories, Abbott Park, IL) and subsequently for HCV RNA (Amplicor HCV, Roche Diagnostics, Basel, Switzerland). Genotype was determined by phylogenetic analysis of the NS5b gene. Seventy-three pregnant women were found to be anti-HCV antibody positive by the first ELISA, but only 28 were anti-HCV positive by both ELISA. The prevalence of anti-HCV antibodies was thus 1.9% (28/1,494) (95% CI: 1.3-2.7%). 21/28 (75%) of the positive samples by both ELISA were HCV RNA positive. The 45 samples that were HCV antibody negative by the second ELISA were also HCV RNA negative. The HCV subtypes identified were 1a (24%), 2f (38%) and 4f (38%). In contrast to previous studies, anti-HCV antibodies were rare among pregnant women in Cameroon. The percentage of HCV seropositive pregnant women who had circulating HCV RNA was similar to that observed in Europe. Several HCV genotypes were found in Cameroon.
The American Journal of Tropical Medicine and Hygiene, Aug 1, 2005
To assess mother-to-child transmission (MTCT) of hepatitis C virus (HCV) in Cameroon, 5,008 pregn... more To assess mother-to-child transmission (MTCT) of hepatitis C virus (HCV) in Cameroon, 5,008 pregnant women were screened for HCV antibodies. Eighty-nine (1.8%) were HCV-antibody (HCV-Ab) positive. Among these, 7 (7.9%) were HBsAg positive, 6 (6.7%) HIV-positive, and one (1.1%) was co-infected by both hepatitis B virus (HBV) and HIV. Sixty-eight (76%) out of 89 HCV-Ab positive pregnant women were HCV-RNA positive. The HCV genotype determination indicated the predominance of genotype 4 (45.3%), followed by the genotypes 1 (28.1%) and 2 (26.6%). The mean HCV-RNA levels of 41 women at the time of delivery was 4.8 (range 0.06-34.7) × 10 6 RNA copies/mL. Finally, 35 women delivered 36 live children. None of those screened at 6 weeks and 6 months of age were HCV-RNA positive. The failure to detect HCV vertical transmission suggests that the mother-to-child transmission (MTCT) is not a major route of HCV transmission in Cameroon.
Lettre des orateurs de sessions de communications orales en partenariat CP6. Sessions de communic... more Lettre des orateurs de sessions de communications orales en partenariat CP6. Sessions de communications orales en partenariat avec le R6seau International des Instituts Pasteur (RIIP) Th~me : Le R~seau International des Instituts Pasteur : son r61e dans le suivi d'interventions th6rapeutiques et vaccinales dans les pays du Sud
The American journal of tropical medicine and hygiene, 2005
To assess mother-to-child transmission (MTCT) of hepatitis C virus (HCV) in Cameroon, 5,008 pregn... more To assess mother-to-child transmission (MTCT) of hepatitis C virus (HCV) in Cameroon, 5,008 pregnant women were screened for HCV antibodies. Eighty-nine (1.8%) were HCV-antibody (HCV-Ab) positive. Among these, 7 (7.9%) were HBsAg positive, 6 (6.7%) HIV-positive, and one (1.1%) was co-infected by both hepatitis B virus (HBV) and HIV. Sixty-eight (76%) out of 89 HCV-Ab positive pregnant women were HCV-RNA positive. The HCV genotype determination indicated the predominance of genotype 4 (45.3%), followed by the genotypes 1 (28.1%) and 2 (26.6%). The mean HCV-RNA levels of 41 women at the time of delivery was 4.8 (range 0.06-34.7) x 10(6) RNA copies/mL. Finally, 35 women delivered 36 live children. None of those screened at 6 weeks and 6 months of age were HCV-RNA positive. The failure to detect HCV vertical transmission suggests that the mother-to-child transmission (MTCT) is not a major route of HCV transmission in Cameroon.
Background: efforts to scale-up HIV treatment in high burden countries have resulted in wider acc... more Background: efforts to scale-up HIV treatment in high burden countries have resulted in wider access to care, improved survival and decreased morbidity for HIV-infected children. the country of Rwanda has made significant achievements in expanding coverage of pediatric HIV services. Methods: We describe the extent of and factors associated with mortality and lost to follow-up (LtF) in children (<15 years) enrolled in HIV care at 39 ICAp-supported facilities across Rwanda from 2004 to 2010 by antiretroviral treatment (ARt) status. We estimated the 1-year cumulative incidence of death and LtF among all children enrolled in care (pre-ARt) and children on ARt. survival analysis was used to evaluate factors associated with death and LtF in both groups. Results: Between January 2004 and June 2010, 3244 children with a median age of 5.7 years (interquartile range 2.8-9.6) enrolled in HIV care. one-year cumulative incidence for death and LtF among pre-ARt children was 4% (95% confidence interval [CI]: 3-5%) and 5% (95% CI: 4-6%), respectively. overall, 2035 (63%) children initiated ARt, median age 6.3 years (interquartile range 3.3-10.4): 1-year Kaplan-Meier estimates of death and LtF were 3% (95% CI: 3-4%) and 1% (95% CI: 1-2%), respectively. Factors associated with an increased hazard for death among pre-ARt children included being <18 months old versus ≥5 years (adjusted sub hazard ratio [asHR] = 4.4, 95% CI: 2.9-6.8) and World Health organization stage IV versus I (asHR = 4.1, 95% CI: 2.0-8.4), whereas children entering care through prevention of mother-to-child transmission had lower hazard than those from voluntary counseling and testing (asHR = 0.50, 95% CI: 0.25-1.0). Markers of advanced disease, including severe immunosuppression (asHR = 0.25, 95% CI: 0.12-0.54), and enrollment in care in rural versus urban clinics (asHR = 0.71, 95% CI: 0.53-0.97) were protective against LtF. For children on ARt, factors associated with hazard of death included younger age (adjusted hazard ratio [aHR] <18 months versus ≥5 years = 2.1, 95% CI: 1.3-3.6), severe malnutrition versus not malnourished (aHR = 3.2, 95% CI: 1.3-8.1), advanced World Health organization stage (aHR IV versus I = 9.8, 95% CI: 3.5-27.4) and severe immunodeficiency versus no evidence (aHR = 2.3, 95% CI: 1.7-3.3). No associations were observed with LtF among children on ARt.
The aim of the study was to evaluate the feasibility of infant feeding options of HIV positive mo... more The aim of the study was to evaluate the feasibility of infant feeding options of HIV positive mothers in urban areas (especially compliance to artificial feeding choices), before the implementation of the infant feeding interventions and procurement of breastmilksubstitutes. We conducted a survey among seropositive women diagnosed during pregnancy and counselled for infant feeding options. At 6 months post delivery an interview was done. 47 mothers were included. Bromocriptine was prescribed to all the mothers who opted for artificial feeding from birth. After counselling 85% of women opted for exclusive artificial feeding of whom 83% mothers practised this option since birth. For those who opted for replacement feeding The main given reason for infant feeding choice was related to medical or nurses advices. Overall 36% [CI 95%, 22-50] of the mothers who opted for artificial milk faced difficulties to afford supplies during the 6 months, leading into an early introduction of paps. Clinical mastitis were mentioned by all those mothers who breastfed. Infant feeding choices were related to the level of education (X2 = 24.10, P = 0.002). Artificial feeding under recovery of cost seems feasible in urban areas in Cameroon and can be facilitate by the administration of antilacteal drugs. More adequate support must be provided for the mother who breastfeed in order to prevent and to treat mastitis. Additional training for counselling in HIV and infant feeding options is recommended for health workers.
Central Africa is considered to be an area of high endemic hepatitis C infection. To determine th... more Central Africa is considered to be an area of high endemic hepatitis C infection. To determine the prevalence of anti-HCV antibodies, HCV RNA, and the genotype distribution in Cameroon, 1,494 pregnant women attending antenatal care units in Yaounde, Cameroon were screened for HCV infection. Anti-HCV antibodies were detected with a 3rd generation ELISA (Monolisa anti-HCV plus version 2, BioRad, Richmond, CA). All anti-HCV antibody-positive sera were then tested with another 3rd generation ELISA (AxSYM) HCV version 3, Abbott Laboratories, Abbott Park, IL) and subsequently for HCV RNA (Amplicor HCV, Roche Diagnostics, Basel, Switzerland). Genotype was determined by phylogenetic analysis of the NS5b gene. Seventy-three pregnant women were found to be anti-HCV antibody positive by the first ELISA, but only 28 were anti-HCV positive by both ELISA. The prevalence of anti-HCV antibodies was thus 1.9% (28/1,494) (95% CI: 1.3-2.7%). 21/28 (75%) of the positive samples by both ELISA were HCV RNA positive. The 45 samples that were HCV antibody negative by the second ELISA were also HCV RNA negative. The HCV subtypes identified were 1a (24%), 2f (38%) and 4f (38%). In contrast to previous studies, anti-HCV antibodies were rare among pregnant women in Cameroon. The percentage of HCV seropositive pregnant women who had circulating HCV RNA was similar to that observed in Europe. Several HCV genotypes were found in Cameroon.
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