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Journal of Acquired Immune Deficiency Syndromes | 2014

Epidemiology of HIV and AIDS among adolescents: current status, inequities, and data gaps.

Priscilla Idele; Amaya Gillespie; Tyler Porth; Chiho Suzuki; Mary Mahy; Susan Kasedde; Chewe Luo

Objectives:To examine levels and patterns of HIV prevalence, knowledge, sexual behavior, and coverage of selected HIV services among adolescents aged 10–19 years and highlight data gaps and challenges. Methods:Data were reviewed from Joint United Nations Programme on HIV/AIDS HIV estimates, nationally representative household surveys, behavioral surveillance surveys, and published literature. Results:A number of gaps exist for adolescent-specific HIV-related data; however, important implications for programming can be drawn. Eighty-two percent of the estimated 2.1 million adolescents aged 10–19 years living with HIV in 2012 were in sub-Saharan Africa, and the majority of these (58%) were females. Comprehensive accurate knowledge about HIV, condom use, HIV testing, and antiretroviral treatment coverage remain low in most countries. Early sexual debut (sex before 15 years of age) is more common among adolescent girls than boys in low- and middle-income countries, consistent with early marriage and early childbirth in these countries. In low and concentrated epidemic countries, HIV prevalence is highest among key populations. Conclusions:Although the available HIV-related data on adolescents are limited, increased HIV vulnerability in the second decade of life is evident in the data. Improving data gathering, analysis, and reporting systems specific to adolescents is essential to monitoring progress and improving health outcomes for adolescents. More systematic and better quality disaggregated data are needed to understand differences by sex, age, geography, and socioeconomic factors and to address equity and human rights obligations, especially for key populations.


Sexually Transmitted Infections | 2010

What will it take to achieve virtual elimination of mother-to-child transmission of HIV? An assessment of current progress and future needs.

Mary Mahy; John Stover; Karusa Kiragu; Chika Hayashi; Priscilla Akwara; Chewe Luo; Karen Stanecki; Rene Ekpini; Nathan Shaffer

Background The number of HIV-positive pregnant women receiving antiretroviral drugs (ARVs) to prevent mother-to-child transmission (MTCT) of HIV has increased rapidly. Objective To estimate the reduction in new child HIV infections resulting from prevention of MTCT (PMTCT) over the past decade. To project the potential impact of implementing the new WHO PMTCT guidelines between 2010 and 2015 and consider the efforts required to virtually eliminate MTCT, defined as <5% transmission of HIV from mother to child, or 90% reduction of infections among young children by 2015. Methods Data from 25 countries with the largest numbers of HIV-positive pregnant women were used to create five scenarios to evaluate different PMTCT interventions. A demographic model, Spectrum, was used to estimate new child HIV infections as a measure of the impact of interventions. Results Between 2000 and 2009 there was a 24% reduction in the estimated annual number of new child infections in the 25 countries, of which about one-third occurred in 2009 alone. If these countries implement the new WHO PMTCT recommendations between 2010 and 2015, and provide more effective ARV prophylaxis or treatment to 90% of HIV-positive pregnant women, 1 million new child infections could be averted by 2015. Reducing HIV incidence in reproductive age women, eliminating the current unmet need for family planning and limiting the duration of breastfeeding to 12 months (with ARV prophylaxis) could avert an additional 264 000 infections, resulting in a total reduction of 79% of annual new child infections between 2009 and 2015, approaching but still missing the goal of virtual elimination of MTCT. Discussion To achieve virtual elimination of new child infections PMTCT programmes must achieve high coverage of more effective ARV interventions and safer infant feeding practices. In addition, a comprehensive approach including meeting unmet family planning needs and reducing new HIV infections among reproductive age women will be required.


BMC Public Health | 2011

Implementing services for Early Infant Diagnosis (EID) of HIV: a comparative descriptive analysis of national programs in four countries.

Anirban Chatterjee; Sangeeta Tripathi; Robert Gass; Ndapewa Hamunime; Sok Panha; Charles Kiyaga; Abdoulaye Wade; Matthew Barnhart; Chewe Luo; Rene Ekpini

BackgroundThere is a significant increase in survival for HIV-infected children who have early access to diagnosis and treatment. The goal of this multi-country review was to examine when and where HIV-exposed infants and children are being diagnosed, and whether the EID service is being maximally utilized to improve health outcomes for HIV-exposed children.MethodsIn four countries across Africa and Asia existing documents and data were reviewed and key informant interviews were conducted. EID testing data was gathered from the central testing laboratories and was then complemented by health facility level data extraction which took place using a standardized and validated questionnaireResultsIn the four countries reviewed from 2006 to 2009 EID sample volumes rose dramatically to an average of >100 samples per quarter in Cambodia and Senegal, >7,000 samples per quarter in Uganda, and >2,000 samples per quarter in Namibia. Geographic coverage of sites also rapidly expanded to 525 sites in Uganda, 205 in Namibia, 48 in Senegal, and 26 in Cambodia in 2009. However, only a small proportion of testing was done at lower-level health facilities: in Uganda Health Center IIs and IIIs comprised 47% of the EID collection sites, but only 11% of the total tests, and in Namibia 15% of EID sites collected >93% of all samples. In all countries except for Namibia, more than 50% of the EID testing was done after 2 months of age. Few sites had robust referral mechanisms between EID and ART. In a sub-sample of children, we noted significant attrition of infants along the continuum of care post testing. Only 22% (Senegal), 37% (Uganda), and 38% (Cambodia) of infants testing positive by PCR were subsequently initiated onto treatment. In Namibia, which had almost universal EID coverage, more than 70% of PCR-positive infants initiated ART in 2008.ConclusionsWhile EID testing has expanded dramatically, a large proportion of PCR- positive infants are initiated on treatment. As EID services continue to scale-up, more programmatic attention and support is needed to retain HIV-exposed infants in care and ensure that those testing positive initiate treatment in a timely manner. Namibias experience demonstrates that it is feasible for a rural, low-income country to achieve high national coverage of infant testing and treatment.


Pediatric Infectious Disease Journal | 1993

Seroprevalence of human immunodeficiency virus type 1 infection in zambian children with tuberculosis

Chifumbe Chintu; Ganapati Bhat; Chewe Luo; Mario Raviglione; Vinod K. Diwan; Herbert L. DuPont; Alimuddin Zumla

Descriptions in the medical literature of human immunodeficiency virus type 1 (HIV-1) in children with tuberculosis (TB) are scanty. This study determined the seroprevalence of HIV-1 in 237 hospitalized children between the ages of 1 month and 14 years with a clinical diagnosis of TB (125 males and 112 females) and in 242 control children (149 males and 93 females). The overall HIV-1 seroprevalence rate in patients with TB was 37% (88 of 237) compared with 10.7% (26 of 242) among the control group (P < 0.00001: odds ratio 5.37, 95% confidence interval = 3.21 < 5.37 < 9.47). HIV-1 seropositivity in children with TB ranged from 53% (31 of 58) in the 12− to 18-month age group to 14% (9 of 61) in the 10− to 14-year-olds. The risk of TB attributable to HIV infection was 29%. The predominant clinical presentation in both seronegative (84.6%) and seropositive (89.7%) groups was that of pulmonary TB and there were no significant differences in clinical presentation between the two groups of patients. Only 54.8% of the patients attended follow-up clinics regularly whereas 32% were lost to follow-up within 3 months. Bacillus Calmette-Guérin vaccination coverage was 87.3% among TB patients and 90.5% in the controls. No significant differences in B. Celmette-Guérin vaccination rates between the seronegative and seropositive children were seen. Coinfection with HIV and TB in children is now one of the major public health problems in Zambian children.


Archives of Disease in Childhood | 1993

Cutaneous hypersensitivity reactions due to thiacetazone in the treatment of tuberculosis in Zambian children infected with HIV-I.

Chifumbe Chintu; Chewe Luo; Ganapati Bhat; Mario Raviglione; Herbert L. DuPont; Alimuddin Zumla

Tuberculosis is one of the most common infections in Zambian adults and children infected with HIV. In Africa, cutaneous hypersensitivity reactions attributed to thiacetazone during treatment of tuberculosis in adults infected with HIV-I have been well documented. This study monitored adverse drug reactions during treatment for tuberculosis over an 18 month period (1 April 1990 to 31 October 1991) in 237 children with a clinical diagnosis of tuberculosis (125 boys and 112 girls; 88/237 (37%) infected with HIV-I) and 242 control children (149 boys and 93 girls; 26/242 (11%) infected with HIV-I). Twenty two (9%) of the 237 children with tuberculosis developed hypersensitivity skin reactions during the course of treatment. Adverse skin reactions were seen more often in children infected with HIV than in those who were not (odds ratio 11.65, 95% confidence interval 3.07 to 34.88). These represented 19 (21%) of 88 children infected with HIV and three (2%) of 149 children not infected with HIV. These skin reactions occurred after a period of treatment ranging between two and four weeks among 14 children receiving the HST (isoniazid, streptomycin, thiacetazone) regimen and eight children receiving the HSTR (isoniazid, streptomycin, thiacetazone, rifampicin) regimen. Twelve (55%) of the 22 children who reacted adversely to treatment developed the Stevens-Johnson syndrome. All 12 of these children with the Stevens-Johnson syndrome were infected with HIV. The mortality among these children who developed the Stevens-Johnson syndrome was 91% (11 of 12 died within three days of the onset of the reaction). No further reactions were observed in the 11 children who recovered from the cutaneous hypersensitivity reactions after thiacetazone was discontinued over a period of six months of further treatment of tuberculosis. The results of this study were in part responsible for the recommendations put forward by the World Health Organization to avoid the use of thiacetazone in the treatment of tuberculosis in children infected with HIV.


Current HIV Research | 2007

Disease Progression in Children with Vertically-Acquired HIV Infection in Sub-Saharan Africa: Reviewing the Need for HIV Treatment

Kirsty Little; Claire Thorne; Chewe Luo; Madeleine J. Bunders; Ngashi Ngongo; Peter McDermott; Marie-Louise Newell

Approximately 700,000 children become newly infected with HIV annually, mainly through mother-to-child transmission (MTCT), making paediatric HIV a leading cause of morbidity and mortality worldwide. The substantial interest in preventing MTCT (PMTCT) has generated information on rates of transmission and associated factors, but there is a lack of information on disease progression and mortality in vertically-infected children, especially from resource-poor settings. Peer-review journals with titles or abstracts containing reference to the reviews themes were selected using widely available search engines. We review relevant literature on mortality in children born to HIV infected mothers; morbidity and mortality associated with paediatric HIV infections; eligibility to and efficacy of antiretroviral therapy (ART). Child mortality is independently associated with maternal HIV status and maternal death, with paediatric infection resulting in approximately 4 fold increase in mortality by age 2 years. Morbidities seen in infected children were similar to those seen in uninfected children, although the rates and recurrences of illness were greater. There is some evidence that progression to AIDS may be more rapid in resource poor settings, although data on this are very limited. PMTCT and paediatric ART have been shown to be highly successful in resource-limited settings, but are not universally applied. Further efforts to increase coverage of both PMTCT and paediatric ART could substantially reduce the numbers of children becoming infected and improve survival of those infected. Additionally, improvements in health infrastructures could improve care provision, not only through improved detection and monitoring but also through treatment of co-morbidities and nutritional support.


Journal of Acquired Immune Deficiency Syndromes | 2012

Progress, challenges, and new opportunities for the prevention of mother-to-child transmission of HIV under the US President's Emergency Plan for AIDS Relief

Benjamin H. Chi; Michelle R. Adler; Omotayo Bolu; Dorothy Mbori-Ngacha; Didier K. Ekouevi; Anna Gieselman; Tsungai Chipato; Chewe Luo; B. Ryan Phelps; Craig McClure; Lynne M. Mofenson; Jeffrey S. A. Stringer

Abstract: In June 2011, the Joint United Nations Programme on HIV/AIDS, the US Presidents Emergency Plan for AIDS Relief (PEPFAR), and other collaborators outlined a transformative plan to virtually eliminate pediatric AIDS worldwide. The ambitious targets of this initiative included a 90% reduction in new pediatric HIV infections and a 50% reduction in HIV-related maternal mortality—all by 2015. PEPFAR has made an unprecedented commitment to the expansion and improvement of prevention of mother-to-child HIV transmission (PMTCT) services globally and is expected to play a critical role in reaching the virtual elimination target. To date, PEPFAR has been instrumental in the success of many national programs, including expanded coverage of PMTCT services, an enhanced continuum of care between PMTCT and HIV care and treatment, provision of more efficacious regimens for antiretroviral prophylaxis, design of innovative but simplified PMTCT approaches, and development of new strategies to evaluate program effectiveness. These accomplishments have been made through collaborative efforts with host governments, United Nations agencies, other donors (eg, the Global Fund for AIDS, Tuberculosis, and Malaria), nongovernmental organizations, and private sector partners. To successfully meet the ambitious global targets to prevent new infant HIV infections, PEPFAR must continue to leverage the existing PMTCT platform, while developing innovative approaches to rapidly expand quality HIV services. PEPFAR must also carefully integrate PMTCT into the broader combination prevention agenda for HIV, so that real progress can be made toward an “AIDS-free generation” worldwide.


Journal of Tropical Pediatrics | 1995

Impact of the Human Immunodeficiency Virus Type-1 on Common Pediatric Illnesses in Zambia

Chifumbe Chintu; Chewe Luo; Ganapati Bhat; Herbert L. DuPont; P. Mwansa-Salamu; M. Kabika; Alimuddin Zumla

The seroprevalence of HIV-1 and in-patient mortality in children with common pediatric illnesses was studied. Between October 1990 and July 1991 at the Department of Paediatrics and Child Health, University Teaching Hospital (UTH), Lusaka, Zambia, mothers of all pediatric admissions were interviewed and counselled for enrollment of their children into the study. Of a total of 1323 children seen, 1266 children (600 female and 666 male) were enrolled into the study. Pneumonia (28 per cent), malaria (24 per cent), malnutrition (18 per cent), and diarrhoea (10 per cent) constituted over 80 per cent of the total admission diagnoses. Tuberculosis (5 per cent) was the fifth commonest cause of admission (61 out of 1266 children). A total of 354 out of the 1266 (28 per cent) children were found to be seropositive for HIV-1 compared to a seroprevalence rate of 9 per cent in children attending accident and emergency for traumatic injuries (P=0.001). High HIV-1 seroprevalence rates were found in children with tuberculosis (69 per cent), malnutrition (41 per cent), pneumonia (28 per cent). and diarrhoea (24 per cent). The overall mortality in hospital among HIV-seropositive children (19 per cent) was significantly higher than those who were HIV-seronegative (9 per cent) (P = < 0.0001).


Aids Care-psychological and Socio-medical Aspects of Aids\/hiv | 2010

Who is the vulnerable child? Using survey data to identify children at risk in the era of HIV and AIDS.

Priscilla Akwara; Behzad Noubary; Patricia Lim Ah Ken; Kiersten Johnson; Rachel Yates; William Winfrey; Upjeet Chandan; Doreen Mulenga; Jimmy Kolker; Chewe Luo

Abstract Over the past decade, there has been increasing global attention to mitigating the impacts of the HIV/AIDS epidemic on childrens lives. Within this context, developing and tracking global child vulnerability indicators in relation to HIV and AIDS has been critical in terms of assessing need and monitoring progress. Although orphanhood and adult household illness (co-residence with a chronically ill or HIV-positive adult) are frequently used as markers, or definitions, of vulnerability for children affected by HIV and AIDS, evidence supporting their effectiveness has been equivocal. Data from 60 nationally representative household surveys (36 countries) were analyzed using bivariate and multivariate methods to establish if these markers consistently identified children with worse outcomes and also to identify other factors associated with adverse outcomes for children. Outcome measures utilized were wasting among children aged 0–4 years, school attendance among children aged 10–14 years, and early sexual debut among adolescent boys and girls aged 15–17 years. Results indicate that orphanhood and co-residence with a chronically ill or HIV-positive adult are not universally robust measures of child vulnerability across national and epidemic contexts. For wasting, early sexual debut, and to a lesser extent, school attendance, in the majority of surveys analyzed, there were few significant differences between orphans and non-orphans or children living with chronically ill or HIV-positive adults and children not living with chronically ill or HIV-positive adults. Of other factors analyzed, children living in households where the household head or eldest female had a primary education or higher were significantly more likely to be attending school, better household health and sanitation was significantly associated with less wasting, and greater household wealth was significantly associated both with less wasting and better school attendance. Of all marker of child vulnerability analyzed, only household wealth consistently showed power to differentiate across age-disaggregated outcomes. Overall, the findings indicate the need for a multivalent approach to defining child vulnerability, one which incorporates household wealth as a key predictor of child vulnerability.


Lancet Infectious Diseases | 2007

Scaling-up co-trimoxazole prophylaxis in HIV-exposed and HIV-infected children in high HIV-prevalence countries

Rony Zachariah; Anthony D. Harries; Chewe Luo; Gretchen Bachman; Stephen M. Graham

Co-trimoxazole (trimethoprim-sulfamethoxazole) is a widely available antibiotic that substantially reduces HIV-related morbidity and mortality in both adults and children. Prophylaxis with co-trimoxazole is a recommended intervention of proven benefit that could serve not only as an initial step towards improving paediatric care in young children with limited access to antiretroviral treatment, but also as an important complement to antiretroviral therapy in resource-limited settings. Despite co-trimoxazoles known clinical benefits, the potential operational benefits, and favourable recommendations by WHO, UNAIDS, and UNICEF, its routine use in developing countries--particularly sub-Saharan Africa--has remained limited. Out of an estimated 4 million children in need of co-trimoxazole prophylaxis (HIV-exposed and HIV-infected), only 4% are currently receiving this intervention. We discuss some of the major barriers preventing the scale-up of co-trimoxazole prophylaxis for children in countries with a high prevalence of HIV and propose specific actions required to tackle these challenges.

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Kirsty Little

University College London

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Herbert L. DuPont

University of Texas at Austin

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Alimuddin Zumla

University College London

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Craig McClure

International AIDS Society

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