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1.
Am J Trop Med Hyg ; 110(4_Suppl): 3-10, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38118172

ABSTRACT

The WHO recommends that all affected countries work toward the elimination of malaria, even those still experiencing a high burden of disease. However, malaria programs in the final phase of elimination or those working to prevent re-establishment of transmission after elimination could benefit from specific evidence-based recommendations for these settings as part of comprehensive and quality-controlled malaria guidelines. The WHO convened an external guideline development group to formulate recommendations for interventions to reduce or prevent malaria transmission in areas with very low- to low-transmission levels and those that have eliminated malaria. In addition, several interventions that could be deployed in higher burden areas to accelerate elimination, such as mass drug administration, were reviewed. Systematic reviews were conducted that synthesized and evaluated evidence for the benefits and harms of public health interventions and summarized critical contextual factors from a health systems perspective. A total of 12 recommendations were developed, with five related to mass interventions that could be deployed at higher transmission levels and seven that would be most appropriate for programs in areas close to elimination or those working to prevent re-establishment of transmission. Four chemoprevention, two active case detection, and one vector control interventions were positively recommended, whereas two chemoprevention and three active case detection interventions were not recommended by the WHO. None of the recommendations were classified as strong given the limited and low-quality evidence base. Approaches to conducting higher quality research in very low- to low-transmission settings to improve the strength of WHO recommendations are discussed.


Subject(s)
Antimalarials , Malaria , Humans , Antimalarials/therapeutic use , Malaria/drug therapy , Mass Drug Administration , Chemoprevention , World Health Organization
2.
PLoS Negl Trop Dis ; 12(12): e0006902, 2018 12.
Article in English | MEDLINE | ID: mdl-30543654

ABSTRACT

BACKGROUND: We examined relationships between schistosome infection, HIV transmission or acquisition, and all-cause death. METHODS: We retrospectively tested baseline sera from a heterosexual HIV-discordant couple cohort in Lusaka, Zambia with follow-up from 1994-2012 in a nested case-control design. Schistosome-specific antibody levels were measured by ELISA. Associations between baseline antibody response to schistosome antigens and incident HIV transmission, acquisition, and all-cause death stratified by gender and HIV status were assessed. In a subset of HIV- women and HIV+ men, we performed immunoblots to evaluate associations between Schistosoma haematobium or Schistosoma mansoni infection history and HIV incidence. RESULTS: Of 2,145 individuals, 59% had positive baseline schistosome-specific antibody responses. In HIV+ women and men, baseline schistosome-specific antibodies were associated with HIV transmission to partners (adjusted hazard ratio [aHR] = 1.8, p<0.005 and aHR = 1.4, p<0.05, respectively) and death in HIV+ women (aHR = 2.2, p<0.001). In 250 HIV- women, presence of S. haematobium-specific antibodies was associated with increased risk of HIV acquisition (aHR = 1.4, p<0.05). CONCLUSION: Schistosome infections were associated with increased transmission of HIV from both sexes, acquisition of HIV in women, and increased progression to death in HIV+ women. Establishing effective prevention and treatment strategies for schistosomiasis, including in urban adults, may reduce HIV incidence and death in HIV+ persons living in endemic areas.


Subject(s)
HIV Infections/epidemiology , HIV/immunology , Schistosoma haematobium/immunology , Schistosoma mansoni/immunology , Schistosomiasis haematobia/epidemiology , Schistosomiasis mansoni/epidemiology , Adult , Animals , Case-Control Studies , Cohort Studies , Female , HIV Infections/mortality , HIV Infections/transmission , Humans , Incidence , Male , Retrospective Studies , Schistosomiasis haematobia/mortality , Schistosomiasis mansoni/mortality , Young Adult , Zambia/epidemiology
3.
Lancet Infect Dis ; 16(4): 465-72, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26809816

ABSTRACT

BACKGROUND: Rapid declines in malaria prevalence, cases, and deaths have been achieved globally during the past 15 years because of improved access to first-line treatment and vector control. We aimed to assess the intervention coverage needed to achieve further gains over the next 15 years. METHODS: We used a mathematical model of the transmission of Plasmodium falciparum malaria to explore the potential effect on case incidence and malaria mortality rates from 2015 to 2030 of five different intervention scenarios: remaining at the intervention coverage levels of 2011-13 (Sustain), for which coverage comprises vector control and access to treatment; two scenarios of increased coverage to 80% (Accelerate 1) and 90% (Accelerate 2), with a switch from quinine to injectable artesunate for management of severe disease and seasonal malaria chemoprevention where recommended for both Accelerate scenarios, and rectal artesunate for pre-referral treatment at the community level added to Accelerate 2; a near-term innovation scenario (Innovate), which included longer-lasting insecticidal nets and expansion of seasonal malaria chemoprevention; and a reduction in coverage to 2006-08 levels (Reverse). We did the model simulations at the first administrative level (ie, state or province) for the 80 countries with sustained stable malaria transmission in 2010, accounting for variations in baseline endemicity, seasonality in transmission, vector species, and existing intervention coverage. To calculate the cases and deaths averted, we compared the total number of each under the five scenarios between 2015 and 2030 with the predicted number in 2015, accounting for population growth. FINDINGS: With an increase to 80% coverage, we predicted a reduction in case incidence of 21% (95% credible intervals [CrI] 19-29) and a reduction in mortality rates of 40% (27-61) by 2030 compared with 2015 levels. Acceleration to 90% coverage and expansion of treatment at the community level was predicted to reduce case incidence by 59% (Crl 56-64) and mortality rates by 74% (67-82); with additional near-term innovation, incidence was predicted to decline by 74% (70-77) and mortality rates by 81% (76-87). These scenarios were predicted to lead to local elimination in 13 countries under the Accelerate 1 scenario, 20 under Accelerate 2, and 22 under Innovate by 2030, reducing the proportion of the population living in at-risk areas by 36% if elimination is defined at the first administrative unit. However, failing to maintain coverage levels of 2011-13 is predicted to raise case incidence by 76% (Crl 71-80) and mortality rates by 46% (39-51) by 2020. INTERPRETATION: Our findings show that decreases in malaria transmission and burden can be accelerated over the next 15 years if the coverage of key interventions is increased. FUNDING: UK Medical Research Council, UK Department for International Development, the Bill & Melinda Gates Foundation, the Swiss Development Agency, and the US Agency for International Development.


Subject(s)
Antimalarials/administration & dosage , Artemisinins/administration & dosage , Culicidae/virology , Insect Vectors/virology , Malaria, Falciparum/prevention & control , Models, Theoretical , Animals , Artesunate , Female , Geography , Humans , Incidence , Insecticide-Treated Bednets , Malaria, Falciparum/epidemiology , Malaria, Falciparum/transmission , Mosquito Control , Prevalence
4.
PLoS One ; 9(5): e96658, 2014.
Article in English | MEDLINE | ID: mdl-24837459

ABSTRACT

BACKGROUND: As new interventions to reduce childhood mortality are identified, careful consideration must be given to identifying populations that could benefit most from them. Promising reductions in childhood mortality reported in a large cluster randomized trial of mass drug administration (MDA) of azithromycin (AZM) prompted the development of visually compelling, easy-to-use tools that synthesize country-specific data on factors that would influence both potential AZM benefit and MDA implementation success. METHODOLOGY/PRINCIPAL FINDINGS: We assessed the opportunity to reduce mortality and the feasibility of implementing such a program, creating Opportunity and Feasibility Indices, respectively. Countries with high childhood mortality were included. A Country Ranking Index combined key variables from the previous two Indices and applied a scoring system to identify high-priority countries. We compared four scenarios with varying weights given to each variable. Twenty-five countries met inclusion criteria. We created easily visualized tools to display the results of the Opportunity and Feasibility Indices. The Opportunity Index revealed substantial variation in the opportunity for an MDA of AZM program to reduce mortality, even among countries with high overall childhood mortality. The Feasibility Index demonstrated that implementing such a program would be most challenging in the countries that could see greatest benefit. Based on the Country Ranking Index, Equatorial Guinea would benefit the most from the MZA of AZM in three of the four scenarios we tested. CONCLUSIONS/SIGNIFICANCE: These visually accessible tools can be adapted or refined to include other metrics deemed important by stakeholders, and provide a quantitative approach to prioritization for intervention implementation. The need to explicitly state metrics and their weighting encourages thoughtful and transparent decision making. The objective and data-driven approach promoted by the three Indices may foster more efficient use of resources.


Subject(s)
Azithromycin/administration & dosage , Child Mortality , Communicable Disease Control/methods , Developing Countries/classification , Health Priorities , Child , Child, Preschool , Humans
5.
J Infect Dis ; 203(2): 258-62, 2011 Jan 15.
Article in English | MEDLINE | ID: mdl-21288826

ABSTRACT

Human immunodeficiency virus type 1 (HIV-1)-specific T cell responses were characterized in a blinded study involving infected individuals and their seronegative exposed uninfected (EU) partners from Lusaka, Zambia. HIV-1-specific T cell responses were detected ex vivo in all infected individuals and amplified, on average, 27-fold following in vitro expansion. In contrast, no HIV-1-specific T cell responses were detected in any of the EU partners ex vivo or following in vitro expansion. These data demonstrate that the detection of HIV-1-specific T cell immunity in EU individuals is not universal and that alternative mechanisms may account for protection in these individuals.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , HIV Infections/immunology , HIV-1/immunology , Sexual Partners , Female , Humans , Immunity, Innate , Male , Zambia
6.
J Int AIDS Soc ; 13: 10, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-20230628

ABSTRACT

BACKGROUND: With the accessibility of prevention of mother to child transmission (PMTCT) services in sub-Saharan Africa, more women are being tested for HIV in antenatal care settings. Involving partners in the counselling and testing process could help prevent horizontal and vertical transmission of HIV. This study was conducted to assess the feasibility of couples' voluntary counseling and testing (CVCT) in antenatal care and to measure compliance with PMTCT. METHODS: A prospective cohort study was conducted over eight months at two public antenatal clinics in Kigali, Rwanda, and Lusaka, Zambia. A convenience sample of 3625 pregnant women was enrolled. Of these, 1054 women were lost to follow up. The intervention consisted of same-day individual voluntary counselling and testing (VCT) and weekend CVCT; HIV-positive participants received nevirapine tablets. In Kigali, nevirapine syrup was provided in the labour and delivery ward; in Lusaka, nevirapine syrup was supplied in pre-measured single-dose syringes. The main outcome measures were nurse midwife-recorded deliveries and reported nevirapine use. RESULTS: In eight months, 1940 women enrolled in Kigali (984 VCT, 956 CVCT) and 1685 women enrolled in Lusaka (1022 VCT, 663 CVCT). HIV prevalence was 14% in Kigali, and 27% in Lusaka. Loss to follow up was more common in Kigali than Lusaka (33% vs. 24%, p = 0.000). In Lusaka, HIV-positive and HIV-negative women had significantly different loss-to-follow-up rates (30% vs. 22%, p = 0.002). CVCT was associated with reduced loss to follow up: in Kigali, 31% of couples versus 36% of women testing alone (p = 0.011); and in Lusaka, 22% of couples versus 25% of women testing alone (p = 0.137). Among HIV-positive women with follow up, CVCT had no impact on nevirapine use (86-89% in Kigali; 78-79% in Lusaka). CONCLUSIONS: Weekend CVCT, though new, was feasible in both capital cities. The beneficial impact of CVCT on loss to follow up was significant, while nevirapine compliance was similar in women tested alone or with their partners. Pre-measured nevirapine syrup syringes provided flexibility to HIV-positive mothers in Lusaka, but may have contributed to study loss to follow up. These two prevention interventions remain a challenge, with CVCT still operating without supportive government policy in Zambia.


Subject(s)
Counseling , HIV Infections/drug therapy , HIV Infections/psychology , Nevirapine/therapeutic use , Patient Compliance , Adult , Cohort Studies , Family Characteristics , Female , HIV Infections/prevention & control , Humans , Infectious Disease Transmission, Vertical/prevention & control , Male , Pregnancy , Prospective Studies , Rwanda , Young Adult , Zambia
7.
PLoS One ; 4(2): e4401, 2009.
Article in English | MEDLINE | ID: mdl-19197365

ABSTRACT

BACKGROUND: Clinical laboratory reference intervals have not been established in many African countries, and non-local intervals are commonly used in clinical trials to screen and monitor adverse events (AEs) among African participants. Using laboratory reference intervals derived from other populations excludes potential trial volunteers in Africa and makes AE assessment challenging. The objective of this study was to establish clinical laboratory reference intervals for 25 hematology, immunology and biochemistry values among healthy African adults typical of those who might join a clinical trial. METHODS AND FINDINGS: Equal proportions of men and women were invited to participate in a cross sectional study at seven clinical centers (Kigali, Rwanda; Masaka and Entebbe, Uganda; two in Nairobi and one in Kilifi, Kenya; and Lusaka, Zambia). All laboratories used hematology, immunology and biochemistry analyzers validated by an independent clinical laboratory. Clinical and Laboratory Standards Institute guidelines were followed to create study consensus intervals. For comparison, AE grading criteria published by the U.S. National Institute of Allergy and Infectious Diseases Division of AIDS (DAIDS) and other U.S. reference intervals were used. 2,990 potential volunteers were screened, and 2,105 (1,083 men and 1,022 women) were included in the analysis. While some significant gender and regional differences were observed, creating consensus African study intervals from the complete data was possible for 18 of the 25 analytes. Compared to reference intervals from the U.S., we found lower hematocrit and hemoglobin levels, particularly among women, lower white blood cell and neutrophil counts, and lower amylase. Both genders had elevated eosinophil counts, immunoglobulin G, total and direct bilirubin, lactate dehydrogenase and creatine phosphokinase, the latter being more pronounced among women. When graded against U.S. -derived DAIDS AE grading criteria, we observed 774 (35.3%) volunteers with grade one or higher results; 314 (14.9%) had elevated total bilirubin, and 201 (9.6%) had low neutrophil counts. These otherwise healthy volunteers would be excluded or would require special exemption to participate in many clinical trials. CONCLUSIONS: To accelerate clinical trials in Africa, and to improve their scientific validity, locally appropriate reference ranges should be used. This study provides ranges that will inform inclusion criteria and evaluation of adverse events for studies in these regions of Africa.


Subject(s)
Chemistry, Clinical , Clinical Laboratory Techniques , Health , Hematology , Adolescent , Adult , Africa, Eastern , Africa, Southern , Bilirubin/metabolism , Biochemistry , Blood Cell Count , Chemistry, Clinical/standards , Eosinophils/metabolism , Female , Hematology/standards , Hemoglobins/metabolism , Humans , Immunoglobulin G/metabolism , L-Lactate Dehydrogenase/metabolism , Male , Middle Aged , National Institute of Allergy and Infectious Diseases (U.S.) , Neutrophils/metabolism , Reference Values , United States
8.
J Acquir Immune Defic Syndr ; 47(1): 108-15, 2008 Jan 01.
Article in English | MEDLINE | ID: mdl-17984761

ABSTRACT

BACKGROUND: : We describe promotional strategies for couples' voluntary HIV counseling and testing (CVCT) and demographic risk factors for couples in Lusaka, Zambia, where an estimated two thirds of new infections occur in cohabiting couples. PRINCIPAL FINDINGS: : CVCT attendance as a function of promotional strategies is described over a 6-year period. Cross-sectional analyses of risk factors associated with HIV in men, women, and couples are presented. Community workers (CWs) recruited from couples seeking CVCT promoted testing in their communities. Attendance dropped when CW outreach ended, despite continued mass media advertisements. In Lusaka, 51% of 8500 cohabiting couples who sought HIV testing were concordant negative for HIV (MF) and 26% concordant positive (MF); 23% had 1 HIV-positive partner and one HIV-negative partner, with 11% HIV-positive man/HIV-negative woman (MF) and 12% HIV-negative man/HIV-positive woman (FM). HIV infection was associated with men's age 30 to 39, women's age 25 to 34, duration of union <3 years, and number of children <2. Even among couples with either 1 or 2 or no risk factors, HIV prevalence was 45% and 29%, respectively. CONCLUSIONS: : Many married African adults do not have high-risk profiles, nor realize that only 1 may be HIV positive. Active and sustained promotion is needed to encourage all couples to be jointly tested and counseled.


Subject(s)
AIDS Serodiagnosis , Counseling , Spouses , Adolescent , Adult , Demography , Female , HIV Infections/prevention & control , Humans , Male , Risk Factors , Zambia
9.
AIDS ; 20(16): 2116-8, 2006 Oct 24.
Article in English | MEDLINE | ID: mdl-17053359

ABSTRACT

Despite the massive expansion of antiretroviral drugs in Africa, little is known about the resulting changes in sexual behavior or obstacles to antiretroviral therapy (ART) adherence. Our evaluation of Rwandan adults on ART found no increase in risky sexual behaviors, but an obstacle to ART initiation and adherence for 76% of patients was a fear of developing too much appetite without enough to eat. Access to adequate nutrition may be a major determinant for long-term adherence to ART.


Subject(s)
Anti-HIV Agents/administration & dosage , Developing Countries , HIV Infections/drug therapy , Nutritional Physiological Phenomena , Patient Compliance , Adult , Attitude to Health , Female , Humans , Male , Rwanda , Sexual Behavior
10.
Trop Med Int Health ; 11(6): 800-3, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16772000

ABSTRACT

The anti-malarial agent chloroquine has activity against HIV. We compared the effect of chloroquine (n = 18) to an anti-malarial agent without known anti-HIV-activity, sulfadoxine-pyrimethamine (n = 12), on breast milk HIV RNA levels among HIV-infected breastfeeding women in Zambia. After adjusting for CD4 count and plasma viral load, chloroquine was associated with a trend towards lower levels of HIV RNA in breast milk compared with sulfadoxine-pyrimethamine (P = 0.05). Higher breastmilk viral load was also observed among women receiving presumptive treatment for symptomatic malaria compared with asymptomatic controls and among controls reporting fever in the prior week. Further research is needed to determine the potential role of chloroquine in prevention of HIV transmission through breastfeeding.


Subject(s)
Anti-HIV Agents/therapeutic use , Antimalarials/therapeutic use , Chloroquine/therapeutic use , HIV Infections/complications , Malaria/drug therapy , Milk, Human/virology , Adult , Breast Feeding , CD4 Lymphocyte Count , Drug Combinations , Female , HIV Infections/epidemiology , Humans , Malaria/complications , Malaria/epidemiology , Milk, Human/drug effects , Pyrimethamine/therapeutic use , RNA, Viral/analysis , Sulfadoxine/therapeutic use , Viral Load , Zambia/epidemiology
11.
AIDS ; 19(6): 603-9, 2005 Mar 24.
Article in English | MEDLINE | ID: mdl-15802979

ABSTRACT

BACKGROUND: Couple counseling has been promoted as a strategy to improve uptake of interventions to prevent mother-to-child HIV transmission (pMTCT) and to minimize adverse social outcomes associated with disclosure of HIV status. OBJECTIVES: We tested whether women counseled antenatally as part of a couple were more likely to accept HIV testing and nevirapine in a pMTCT program, and whether they would be less likely to experience later adverse social events than women counseled alone. METHODS: A pMTCT program that included active community education and outreach to encourage couple counseling and testing was implemented in two antenatal clinics in Lusaka, Zambia. A subset of HIV-positive women was asked to report their experience of adverse social events 6 months after delivery. Couple-counseled women were compared with individual-counseled women stratified by whether or not they had disclosed their HIV status to their partners. RESULTS: Nine percent (868) of 9409 women counseled antenatally were counseled with their husband. Couple-counseled women were more likely to accept HIV testing (96%) than women counseled alone (79%); however uptake of nevirapine was not improved. Six months after delivery, 28% of 324 HIV-positive women reported at least one adverse social event (including physical violence, verbal abuse, divorce or separation). There were no significant differences in reported adverse social events between couple- and individual-counseled women. CONCLUSIONS: Couple counseling did not increase the risk of adverse social events associated with HIV disclosure. Support services and interventions to improve social situations for people living with HIV need to be further evaluated.


Subject(s)
Counseling/statistics & numerical data , HIV Infections/prevention & control , Infectious Disease Transmission, Vertical/prevention & control , Patient Acceptance of Health Care/statistics & numerical data , Pregnancy Complications, Infectious/prevention & control , Prenatal Care/statistics & numerical data , Adult , Anti-HIV Agents/therapeutic use , Breast Feeding , Cohort Studies , Disclosure , Divorce , Domestic Violence , Family Characteristics , Female , HIV Infections/transmission , Humans , Nevirapine/therapeutic use , Pregnancy , Prospective Studies , Risk Factors , Zambia
12.
Control Clin Trials ; 25(4): 353-65, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15296810

ABSTRACT

PURPOSE: We present the rationale and design of the Zambian Exclusive Breast-feeding Study (ZEBS), a randomized trial evaluating the efficacy of short-duration exclusive breast-feeding (EBF) as a strategy to reduce postnatal human immunodeficiency virus (HIV) transmission while preserving the other health benefits of this important mode of infant feeding. METHODS: One thousand two hundred HIV-positive pregnant women were recruited in Lusaka, Zambia, and followed with their infants for 24 months. In addition to Nevirapine (NVP), all women received intensive and frequent clinic- and home-based counseling to support exclusive breast-feeding. When the infant was 1 week of age, half of the women were randomly assigned to a group encouraged to abruptly (<24 h) cease all breast-feeding at 4 months. The primary outcome of the experimental (randomized) comparison is HIV-free survival at 24 months. The design is also observational and will compare HIV transmission rates between those who do and do not adhere to the counseling intervention promoting exclusive breast-feeding. CONCLUSION: Our study aims to quantify the benefit-risk ratio of early cessation of exclusive breast-feeding to interrupt mother-to-child transmission of HIV with an intensive behavioral intervention and has both observational and experimental analytic approaches. Our study design assesses efficacy and also has a prominent applied component that if the intervention is effective, it will permit rapid and sustainable adoption within low-resource communities.


Subject(s)
Behavior Therapy/methods , Breast Feeding/ethnology , Health Behavior , Health Promotion , Counseling/methods , Female , Follow-Up Studies , HIV Seropositivity/epidemiology , Health Education , Humans , Infant , Prospective Studies , Zambia
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