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Background: Recent HIV infection surveillance can help to identify populations and geographies with active transmission. We compared risk factors among recent and long-term infections from the initial ten months of [...]

We used data from the 1996 Honduras National Micronutrient Survey to investigate the co-occurrence of vitamin A deficiency (VAD), anemia and stunting in a representative sample of Honduran children 1-5 y old. Observed frequencies of co-occurrence were compared with frequencies expected by chance in children 12-35.9 mo old (n = 633) and 36-59.9 mo old (n = 610) for the three possible two-way combinations of the problems and the three-way combination. Observed frequencies were greater than expected frequencies for all eight comparisons, and all comparisons except for that of stunting and anemia in younger children were significant. The observed frequency of the three-way co-occurrence was 8.4% compared with an expected co-occurrence of 8.1% in younger children (P: < 0.05) and 4.8% compared with 4.2%, respectively, in older children (P: < 0.001). Although there was statistical evidence for co-occurrence, differences between expected and observed prevalences were small for most comparisons. Our findings suggest that having one or two problems does not appreciably increase the probability of having another. The efficiency of nutrition interventions aimed at these conditions would not be improved by targeting children with any one of the conditions; rather, the three conditions should be treated as virtually independent when designing programs. Replication of this study in other settings is warranted. [ABSTRACT FROM AUTHOR]

Abstract Background A new generation of diagnostic tests, the interferon-γ release assays (IGRAs), have been developed for the detection of latent tuberculosis infection (LTBI). Limited data are available on their use in HIV-infected persons. Methods A cross-sectional study was carried out at 2 HIV clinics in Atlanta to assess the utility of two IGRA tests (T-SPOT.TB [TSPOT] and QuantiFERON-TB Gold in Tube [QFT-3G]) compared to the tuberculin skin test (TST). Results 336 HIV-infected persons were enrolled. Median CD4 count was 335 cells/μl and median HIV viral load was 400 copies/ml. Overall, 27 patients (8.0%) had at least 1 positive diagnostic test for LTBI: 7 (2.1%) had a positive TST; 9 (2.7%) a positive QFT-3G; and 14 (4.2%) a positive TSPOT. Agreement between the 3 diagnostic tests was poor: TST and TSPOT, [κ = 0.16, 95% CI (-0.06, 0.39)], TST and QFT-3G [κ = 0.23, 95% CI (-0.05, 0.51)], QFT-3G and TSPOT [κ = 0.06, 95% CI (-0.1, 0.2)]. An indeterminate test result occurred among 6 (1.8%) of QFT-3G and 47 (14%) of TSPOT tests. In multivariate analysis, patients with a CD4 ≤ 200 cells/μl were significantly more likely to have an indeterminate result [OR = 3.6, 95% CI (1.9, 6.8)]. Conclusion We found a low prevalence of LTBI and poor concordance between all 3 diagnostic tests. Indeterminate test results were more likely at CD4 counts ≤ 200 cells/μl. Additional studies among HIV-infected populations with a high prevalence of TB are needed to further assess the utility of IGRAs in this patient population.

Background: A new generation of diagnostic tests, the interferon-gamma release assays (IGRAs), have been developed for the detection of latent tuberculosis infection (LTBI). Limited data are available on their use in HIV-infected persons.Methods: A cross-sectional study was carried out at 2 HIV clinics in Atlanta to assess the utility of two IGRA tests (T-SPOT.TB [TSPOT] and QuantiFERON-TB Gold in Tube [QFT-3G]) compared to the tuberculin skin test (TST).Results: 336 HIV-infected persons were enrolled. Median CD4 count was 335 cells/microl and median HIV viral load was 400 copies/ml. Overall, 27 patients (8.0%) had at least 1 positive diagnostic test for LTBI: 7 (2.1%) had a positive TST; 9 (2.7%) a positive QFT-3G; and 14 (4.2%) a positive TSPOT. Agreement between the 3 diagnostic tests was poor: TST and TSPOT, [kappa = 0.16, 95% CI (-0.06, 0.39)], TST and QFT-3G [kappa = 0.23, 95% CI (-0.05, 0.51)], QFT-3G and TSPOT [kappa = 0.06, 95% CI (-0.1, 0.2)]. An indeterminate test result occurred among 6 (1.8%) of QFT-3G and 47 (14%) of TSPOT tests. In multivariate analysis, patients with a CD4 < or = 200 cells/microl were significantly more likely to have an indeterminate result [OR = 3.6, 95% CI (1.9, 6.8)].Conclusion: We found a low prevalence of LTBI and poor concordance between all 3 diagnostic tests. Indeterminate test results were more likely at CD4 counts < or = 200 cells/microl. Additional studies among HIV-infected populations with a high prevalence of TB are needed to further assess the utility of IGRAs in this patient population. [ABSTRACT FROM AUTHOR]

We compared characteristics of HIV diagnosis and recent HIV infection (ie, likely acquired within the last year) in Cambodia. We included individuals ≥ 15 years old accessing HIV testing. From August 2020 to August 2022, 53 031 people were tested for HIV, 6868 were newly diagnosed, and 192 were recently infected. We found differences in geographical burden and risk behaviors with diagnosis and recency (eg, men who have sex with men, transgender women, and entertainment workers had a nearly 2-fold increased odds of testing positive for recent infection compared to being diagnosed with HIV). Recent infection surveillance may provide unique insights into ongoing HIV acquisition to inform programs., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2023.)

Introduction: Great strides in responding to the HIV epidemic have led to improved access to and uptake of HIV services in Guyana, a lower-middle-income country with a generalized HIV epidemic. Despite efforts to scale up HIV treatment and adopt the test and start strategy, little is known about costs of HIV services across the care cascade., Methods: We collected cost data from the national laboratory and nine selected treatment facilities in five of the country's ten Regions, and estimated the costs associated with HIV testing and services (HTS) and antiretroviral therapy (ART) from a provider perspective from January 1, 2016 to December 31, 2016. We then used the unit costs to construct four resource allocation scenarios. In the first two scenarios, we calculated how close Guyana would currently be to its 2020 targets if the allocation of funding across programs and regions over 2017-2020 had (a) remained unchanged from latest-reported levels, or (b) been optimally distributed to minimize incidence and deaths. In the next two, we estimated the resources that would have been required to meet the 2020 targets if those resources had been distributed (a) according to latest-reported patterns, or (b) optimally to minimize incidence and deaths., Results: The mean cost per test was US$15 and the mean cost per person tested positive was US$796. The mean annual cost per of maintaining established adult and pediatric patients on ART were US$428 and US$410, respectively. The mean annual cost of maintaining virally suppressed patients was US$648. Cost variation across sites may suggest opportunities for improvements in efficiency, or may reflect variation in facility type and patient volume. There may also be scope for improvements in allocative efficiency; we estimated a 28% reduction in the total resources required to meet Guyana's 2020 targets if funds had been optimally distributed to minimize infections and deaths., Conclusions: We provide the first estimates of costs along the HIV cascade in the Caribbean and assessed efficiencies using novel context-specific data on the costs associated with diagnostic, treatment, and viral suppression. The findings call for better targeting of services, and efficient service delivery models and resource allocation, while scaling up HIV services to maximize investment impact., Competing Interests: The authors declare no competing interests.

In the Caribbean region, HIV prevalence is high among key population (KP) groups, such as sex workers and men who have sex with men. However, there is a lack of high-quality, population-level data estimating HIV prevalence and population sizes of KPs. The President's Emergency Plan for AIDS Relief has funded and completed five bio-behavioral surveillance (BBS) surveys using respondent-driven sampling methodology to target KP in the English-speaking Caribbean region. We describe the experience of implementing bio-behavioral surveys in the Caribbean region and document the context, processes, successes, and challenges, and make recommendations for future survey implementation. Successes include the provision of estimates of nationally representative HIV data and KP size estimates to improve HIV programming and provision of tools for routinization of BBS. Challenges include small KP sizes, the legal context, and the cost and speed of implementation. Future bio-behavioral surveys should include well-planned formative assessments and stakeholder involvement.

Scientific evidence showing the benefits of early initiation of antiretroviral therapy (ART) prompted World Health organization (WHO) to recommend that all persons diagnosed as HIV positive should commence ART irrespective of CD4 count and disease progression. Based on this recommendation, countries should adopt and implement the HIV "Treat All" policy to achieve the UNAIDS 90-90-90 targets and ultimately reach epidemic control. Attaining this goal along the HIV treatment cascade depends on the laboratory to monitor progress and measure impact. The laboratory plays an important role in HIV diagnosis to attain the first 90 and in viral load (VL) and HIV drug resistance testing to reinforce adherence, improve viral suppression, and measure the third 90. Countries in the Caribbean region have endorsed the WHO HIV "Treat all" recommendation; however, they are faced with diminishing financial resources to support laboratory testing, seen as a rate-limiting factor to achieving this goal. To improve laboratory coverage with fewer resources in the Caribbean there is the need to optimize laboratory operations to ensure the implementation of high quality, less expensive evidence-based approaches that will result in more efficient and effective service delivery. Suggested practical and innovative approaches to achieve this include: (1) targeted testing within HIV hotspots; (2) strengthening sample referral systems for VL; (3) better laboratory data collection systems; and (4) use of treatment cascade data for programmatic decision-making. Furthermore, strengthening quality improvement and procurement systems will minimize diagnostic errors and guarantee a continuum of uninterrupted testing which is critical for routine monitoring of patients to meet the stated goal.

Background: Implementing quality management systems and accrediting laboratories in the Caribbean has been a challenge., Objectives: We report the development of a stepwise process for quality systems improvement in the Caribbean Region., Methods: The Caribbean Laboratory Stakeholders met under a joint Pan American Health Organization/US Centers for Disease Control and Prevention initiative and developed a user-friendly framework called 'Laboratory Quality Management System - Stepwise Improvement Process (LQMS-SIP) Towards Accreditation' to support countries in strengthening laboratory services through a stepwise approach toward fulfilling the ISO 15189: 2012 requirements., Results: This approach consists of a three-tiered framework. Tier 1 represents the minimum requirements corresponding to the mandatory criteria for obtaining a licence from the Ministry of Health of the participating country. The next two tiers are quality improvement milestones that are achieved through the implementation of specific quality management system requirements. Laboratories that meet the requirements of the three tiers will be encouraged to apply for accreditation. The Caribbean Regional Organisation for Standards and Quality hosts the LQMS-SIP Secretariat and will work with countries, including the Ministry of Health and stakeholders, including laboratory staff, to coordinate and implement LQMS-SIP activities. The Caribbean Public Health Agency will coordinate and advocate for the LQMS-SIP implementation., Conclusion: This article presents the Caribbean LQMS-SIP framework and describes how it will be implemented among various countries in the region to achieve quality improvement., Competing Interests: The authors declare that they have no financial or personal relationship(s) that may have inappropriately influenced them in writing this article.

In 2008, HIV rapid testing (HIV RT) was only minimally used in the Caribbean region. Collaboration with countries and international partners since then has resulted in greater availability and use of HIV RT services. Surveys were conducted in 2012 and 2014 among 11 selected Caribbean countries to inform stakeholders of progress made since 2008 and to identify strategies to further improve access and uptake of high-quality HIV RT in community- and facility-based settings in support of the UNAIDS 90-90-90 targets. Key accomplishments during this period include (1) presence of in-country national HIV RT algorithms, (2) use of the dried tube specimen (DTS) as an external quality assessment (EQA) program, (3) use of standardized logbooks for data collection and monitoring, and (4) use of oral fluid for HIV RT, particularly for key population surveys. Although progress has been made since 2008 to increase access and improve the quality of HIV RT among countries in the Caribbean, some work remains to be done. This includes the development of new policies and implementation of existing ones, task shifting, quality and access to testing, testing strategies, and integration of HIV RT into HIV Testing Services.

Background: Past efforts to improve laboratory quality systems and to achieve accreditation for better patient care in the Caribbean Region have been slow., Objective: To describe the impact of the Strengthening of Laboratory Management Toward Accreditation (SLMTA) training programme and mentorship amongst five clinical laboratories in the Caribbean after 18 months., Method: Five national reference laboratories from four countries participated in the SLMTA programme that incorporated classroom teaching and implementation of improvement projects. Mentors were assigned to the laboratories to guide trainees on their improvement projects and to assist in the development of Quality Management Systems (QMS). Audits were conducted at baseline, six months, exit (at 12 months) and post-SLMTA (at 18 months) using the Stepwise Laboratory Quality Improvement Process Towards Accreditation (SLIPTA) checklist to measure changes in implementation of the QMS during the period. At the end of each audit, a comprehensive implementation plan was developed in order to address gaps., Results: Baseline audit scores ranged from 19% to 52%, corresponding to 0 stars on the SLIPTA five-star scale. After 18 months, one laboratory reached four stars, two reached three stars and two reached two stars. There was a corresponding decrease in nonconformities and development of over 100 management and technical standard operating procedures in each of the five laboratories., Conclusion: The tremendous improvement in these five Caribbean laboratories shows that SLMTA coupled with mentorship is an effective, user-friendly, flexible and customisable approach to the implementation of laboratory QMS. It is recommended that other laboratories in the region consider using the SLMTA training programme as they engage in quality systems improvement and preparation for accreditation.

Background: School closures were widely implemented in Argentina during the 2009 H1N1 influenza virus pandemic., Objectives: To assess the economic impact of school closures on households, their effectiveness in preventing children from engaging in social group activities, and parental attitudes toward them., Methods: Three schools that closed for 2 weeks in response to the pandemic were identified in two socioeconomically distinct cities in Argentina. All households with children enrolled in these schools were surveyed. Direct and indirect costs attributable to closures were estimated from the household perspective. Other information collected included children activities during the closures and parental attitudes toward the intervention., Results: Completed questionnaires were returned by 45% of surveyed households. Direct and indirect costs due to closures represented 11% of imputed monthly household income in the city with lower socioeconomic status, and 3% in the other city (P=0·01). Non-childcare expenses and loss of workdays were more common in the city with lower socioeconomic status. Childcare expenses were less common and were experienced by a similar percentage of households in both cities. About three-quarters of respondents in both cities agreed with the closures. The main concern among those who disagreed with closures was their negative impact on education. Children in more than two-thirds of affected households left their home at least once during the closures to spend time in public places., Conclusion: School closures may more significantly impact low-income households. Authorities should consider the range of economic impacts of school closures among families when planning their implementation., (© 2012 John Wiley & Sons Ltd.)

School closures are used to reduce seasonal and pandemic influenza transmission, yet evidence of their effectiveness is sparse. In Argentina, annual winter school breaks occur during the influenza season, providing an opportunity to study this intervention. We used 2005-2008 national weekly surveillance data of visits to a health care provider for influenza-like illness (ILI) from all provinces. Using Serfling-specified Poisson regressions and population-based census denominators, we developed incidence rate ratios (IRRs) for the 3 weeks before, 2 weeks during, and 3 weeks after the break. For persons 5-64 years of age, IRRs were <1 for at least 1 week after the break. Observed rates returned to expected by the third week after the break; overall decrease among persons of all ages was 14%. The largest decrease was among children 5-14 years of age during the week after the break (37% lower IRR). Among adults, effects were weaker and delayed. Two-week winter school breaks significantly decreased visits to a health care provider for ILI among school-aged children and nonelderly adults.

Setting: Persons in whom targeted testing for latent tuberculosis infection (LTBI) is recommended in Seattle, Washington; Atlanta, Georgia; and central North Carolina, United States., Objective: To compare the performance of an interferon-gamma release assay (QuantiFERON®-TB Gold In-Tube [QFT-GIT]) with the tuberculin skin test (TST) among foreign-born, homeless, human immunodeficiency virus (HIV) infected and substance abuse persons tested for LTBI., Design: A cross-sectional study requiring participants to have a blood test, a TST and data collected., Results: Of 1653 persons, 19.5% were TST-positive and 14.0% were QFT-GIT-positive. Overall concordance was moderate (kappa 0.53; 95%CI 0.47-0.58). Compared to concordant positive results, TST+/QFT-GIT- discordance was associated with HIV infection and sex, while TST-/QFT-GIT+ discordance was associated with HIV and inversely associated with foreign birth. Compared to concordant negative results, TST-/QFT-GIT+ discordance was associated with foreign birth and age ≥50 years, while TST+/QFT-GIT-discordance was associated with foreign birth, age 30-49 years, being Black and inversely associated with HIV. HIV infection was significantly associated with indeterminate QFT-GIT results., Conclusion: QFT-GIT may be an improvement over the TST for diagnosing LTBI in foreign-born and older persons, and may be as useful as the TST in HIV-infected persons. The sensitivity of both tests may be low in HIV-infected persons.

At a major referral hospital in the Southern Hemisphere, the 2009 influenza A (H1N1) pandemic brought increased critical care demand and more unscheduled nursing absences. Because of careful preparedness planning, including rapid expansion and redistribution of the numbers of available beds and staff, hospital surge capacity was not exceeded.

This article describes two large, multisite infectious disease programs: the Tuberculosis Epidemiologic Studies Consortium (TBESC) and the Emerging Infections Programs (EIPs). The links between biological anthropology and applied public health are highlighted using these programs as examples. Funded by the Centers for Disease Control and Prevention (CDC), the TBESC and EIPs conduct applied public health research to strengthen infectious disease prevention and control efforts in the United States. They involve collaborations among CDC, public health departments, and academic and clinical institutions. Their unique role in national infectious disease work, including their links to anthropology, shared elements, key differences, strengths and challenges, is discussed.

Success in reducing tuberculosis (TB) incidence in developed nations has created a paradoxical problem for researchers. In many countries, there are too few cases to support the research necessary to maintain and accelerate the decline. We describe an approach to applied TB research that supports and focuses efforts of researchers at 21 academic, clinical, and governmental sites in two countries. The Tuberculosis Epidemiologic Studies Consortium (TBESC), funded by the Centers for Disease Control and Prevention (CDC) and by outside sources, conducts programmatically relevant epidemiologic, behavioral, economic, laboratory, and operational research for TB prevention and control. Our experience may serve as a model for other types of applied health care research.

In 1959, the Arden House Conference on Tuberculosis inaugurated modern tuberculosis control strategy by declaring that curative treatment of tuberculosis is a public health obligation. In the decades after the conference, tuberculosis rates decreased more slowly than forecast, perhaps because chemotherapy had less impact than anticipated, or because the conference's recommendations were not implemented fully until 30 years later, when an epidemic resurgence jolted the country out of complacency. Since 1959, several broad issues have gained prominence after being overlooked or unexpected at the time of the Arden House Conference. These include tuberculosis outbreaks, contact investigations, treatment of latent Mycobacterium tuberculosis infection, briefer treatment regimens, human immunodeficiency virus infection, bacteriology laboratory capabilities, and transnational migration. Trends and experience have shown that tuberculosis elimination in the United States will be unfeasible until both technological advances and social justice allow control systems to be applied throughout the world.

The goal of this study was to assess the impact of improved stoves, house ventilation, and child location on levels of indoor air pollution and child exposure in a rural Guatemalan population reliant on wood fuel. The study was a random sample of 204 households with children less than 18 months in a rural village in the western highlands of Guatemala. Socio-economic and household information was obtained by interview and observation. Twenty-four hour carbon monoxide (CO) was used as the primary measure of kitchen pollution and child exposure in all homes, using Gastec diffusion tubes. Twenty-four hour kitchen PM(3.5) was measured in a random sub-sample (n=29) of kitchens with co-located CO tubes. Almost 50% of the homes still used open fires, around 30% used chimney stoves (planchas) mostly from a large donor-funded programme, and the remainder of homes used various combinations including bottled gas and open fires. The 24-h kitchen CO was lowest for homes with self-purchased planchas: mean (95% CI) CO of 3.09 ppm (1.87-4.30) vs. 12.4 ppm (10.2-14.5) for open fires. The same ranking was found for child CO exposure, but with proportionately smaller differentials (P<0.0001). The 24-h kitchen PM(3.5) in the sub-sample showed similar differences (n=24, P<0.05). The predicted child PM for all 203 children (based on a regression model from the sub-sample) was 375 microg/m(3) (270-480) for self-purchased planchas and 536 microg/m(3) (488-584) for open fires. Multivariate analysis showed that stove/fuel type was the most important determinant of kitchen CO, with some effect of kitchen volume and eaves. Stove/fuel type was also the key determinant of child CO, with some effect of child position during cooking. The improved stoves in this community have been effective in reducing indoor air pollution and child exposure, although both measures were still high by international standards. Large donor-funded stove programmes need to aim for wider acceptance and uptake by the local families. Better stove maintenance is also required.

Background: Lead is a component of tobacco and tobacco smoke, and smokers have higher blood lead levels than do nonsmokers., Methods: We examined the relation between second-hand smoke exposure and blood lead levels in a nationally representative sample of 5592 U.S. children, age 4-16 years, who participated in the Third National Health and Nutrition Examination Survey (1988-1994). Linear and logistic regression modeling was used to adjust for known covariates., Results: Geometric mean blood lead levels were 1.5 mug/dL, 1.9 mug/dL, and 2.6 mug/dL for children with low, intermediate, and high cotinine levels, respectively. The adjusted linear regression model showed that geometric mean blood lead levels were 38% higher (95% confidence interval [CI] = 25-52%) in children with high cotinine levels compared with children who had low cotinine levels. The logistic regression models showed that children with high cotinine levels were more likely to have blood lead levels >/=10 mug/dL than were children with low cotinine levels (odds ratio [OR] = 4.4; CI = 1.9-10.5)., Conclusions: Second-hand smoke could be associated with increased blood lead levels in U.S. children aged 4-16 years.

The authors evaluated mean blood lead levels (BLLs) and the prevalence of elevated BLLs in children 1-6 yr of age living in Torreón, Mexico, and assessed risk factors for lead exposure in these children. The study involved a simple random sample of households in the area around a local smelter, as well as a 2-stage cluster sample of neighborhoods and households in the remainder of Torreón. The geometric mean BLL of children in this study (N = 367) was 6.0 microg/dl (95% confidence interval [CI] = 5.2, 6.8) (0.29 microM/l [95% CI = 0.25, 0.33]). Twenty percent of the children had BLLs > or = 10 microg/dl (0.48 microM/l), and 5% had BLLs > or = 20 microg/dl (0.97 microM/l). In multivariate analyses, distance from the smelter, amount of income, and education level of the primary caregiver predicted BLLs. In the environmental risk factor subsample (n = 124), dust and soil lead levels were associated with BLLs and distance from the smelter. BLLs in this study were moderately high, but the levels were lower than those in other smelting communities prior to remediation.

The phase-out of leaded gasoline began in Jakarta, Indonesia on July 1, 2001. We evaluated mean blood lead levels (BLLs) and the prevalence of elevated BLLs of Jakarta school children and assessed risk factors for lead exposure in these children before the beginning of the phase-out activities. The study involved a population-based, cross-sectional blood lead survey that included capillary blood lead sampling and a brief questionnaire on risk factors for lead poisoning. A cluster survey design was used. Forty clusters, defined as primary schools in Jakarta, and 15 2nd- and 3rd-grade children in each cluster were randomly selected for participation in the study. The average age of children in this study was 8.6 years (range 6-12) and the geometric mean BLL of the children was 8.6 microg/dl (median: 8.6 microg/dl; range: 2.6-24.1 microg/dl) (n=397). Thirty-five percent of children had BLLs > or =10 microg/dl and 2.4% had BLLs > or =20 microg/dl. Approximately one-fourth of children had BLLs 10-14.9 microg/dl. In multivariate models, level of education of the child's primary caregiver, water collection method, home varnishing and occupational recycling of metals, other than lead, by a family member were predictors of log BLLs after adjustment for age and sex. BLLs of children who lived near a highway or major intersection were significantly higher than those of children who lived near a street with little or no traffic when level of education was not included in the model. Water collection method was a significant predictor of BLLs > or =10 microg/dl after adjustment for age and sex. BLLs in children in this study were moderately high and consistent with BLLs of children in other countries where leaded gasoline is used. With the phase-out of leaded gasoline, BLLs of children in Jakarta are expected to rapidly decline as they have in other countries that have phased lead out of gasoline., (Copyright 2002 Elsevier Science B.V.)

We compared the positive deviance (PD) approach in Save the Children's field guide with a case-control study (CCS) to identify behaviors associated with good nutritional status in Afghan refugee children 6 to 24 months of age in the Northwest Frontier Province (NWFP), Pakistan. The positive deviance inquiry (PDI), utilizing observations and interviews with mothers, fathers, and secondary caregivers in eight households, identified 12 feeding, caring, and health-seeking behaviors that were not widely practiced. The CCS, using the same selection criteria and content as the PDI with 50 mother-child pairs not in the PDI, yielded six significant associations with good nutritional status. Both the PDI and CCS detected feeding behaviors. The PDI alone identified complex phenomena (active feeding and maternal affect). The CCS alone confirmed the beneficial use of health services. The PD approach was an affordable, participatory, and valid method to identify feeding behaviors and other factors associated with good nutrition in this context.

Improved biomass cookstoves have the potential to reduce pollutant emissions and thereby reduce pollution exposure among populations in developing countries who cook daily with biomass fuels. However, evaluation of such interventions has been very limited. This article presents results from a study carried out in 30 households in rural Guatemala. Twenty-four hour PM3.5 concentrations were compared over 8 months for three fuel/cookstove conditions (n = 10 households for each condition): a traditional open fire cookstove, an improved cookstove called the plancha mejorada, and a liquefied petroleum gas (LPG) stove/open fire combination. Twenty-four hour geometric mean PM3.5 concentrations were 1560 micrograms/m3 (n = 58; 95% C.I. 1310, 1850), 280 micrograms/m3 (n = 59; 95% C.I. 240-320), and 850 micrograms/m3 (n = 60; 95% C.I. 680-1050) for the open fire, plancha, and LPG/open fire combination, respectively. A generalized estimating equation model showed a 45% reduction in PM3.5 concentrations for the LPG/open fire combination as compared to the open fire alone. The difference approached significance (p < 0.0737). The plancha showed an 85% reduction in PM3.5 concentrations as compared to the open fire (p < 0.0001). An analysis of the interaction of time with stove type showed that the temporal trend in pollution did not significantly differ among the three stove types. The reduced PM3.5 concentrations were maintained over time. Season did not affect pollutant concentrations. Of the two interventions, the plancha appears to offer the best prospects for achieving substantial reductions in indoor air pollution levels, although issues of cost and stove maintenance remain to be addressed.

Around 50% of people, almost all in developing countries, rely on coal and biomass in the form of wood, dung and crop residues for domestic energy. These materials are typically burnt in simple stoves with very incomplete combustion. Consequently, women and young children are exposed to high levels of indoor air pollution every day. There is consistent evidence that indoor air pollution increases the risk of chronic obstructive pulmonary disease and of acute respiratory infections in childhood, the most important cause of death among children under 5 years of age in developing countries. Evidence also exists of associations with low birth weight, increased infant and perinatal mortality, pulmonary tuberculosis, nasopharyngeal and laryngeal cancer, cataract, and, specifically in respect of the use of coal, with lung cancer. Conflicting evidence exists with regard to asthma. All studies are observational and very few have measured exposure directly, while a substantial proportion have not dealt with confounding. As a result, risk estimates are poorly quantified and may be biased. Exposure to indoor air pollution may be responsible for nearly 2 million excess deaths in developing countries and for some 4% of the global burden of disease. Indoor air pollution is a major global public health threat requiring greatly increased efforts in the areas of research and policy-making. Research on its health effects should be strengthened, particularly in relation to tuberculosis and acute lower respiratory infections. A more systematic approach to the development and evaluation of interventions is desirable, with clearer recognition of the interrelationships between poverty and dependence on polluting fuels.

Vital capacity and residual lung volume (in terms of 1/min or ml/m 2 of body surface area) of 357 subjects (205 males, 152 females) was evaluated in La Paz, Bolivia, situated at 3,750 m. The sample included: (1) 37 high altitude rural natives (all male), (2) 125 high altitude urban natives (69 male, 58 female), (3) 85 Bolivians of foreign ancestry acclimatized to high altitude since birth (40 male, 45 female), (4) 63 Bolivians of foreign ancestry acclimatized to high altitude during growth (30 male, 33 female), and (5) 47 non-Bolivians of either European or North American ancestry acclimatized to high altitude during adulthood (24 male, 23 female). Results indicate that (1) all samples studied, irrespective of origin or acclimatization status, have larger lung volumes than those predicted from sea level norms; (2) the high altitude rural natives have significantly greater lung volumes (vital capacity and residual lung volume) than the high altitude urban natives and all the non-native high altitude samples; (3) males acclimatized to high altitude since birth or during growth attain similar lung volumes as high altitude urban natives and higher residual lung volumes than subjects acclimatized to high altitude during adulthood but lower than the high altitude rural natives; (4) females acclimatized to high altitude since birth or during growth attain similar lung volumes as subjects acclimatized to high altitude during adulthood; (5) age at arrival to high altitude is inversely related to residual lung volume but not vital capacity; (6) among subjects acclimatized to high altitude during growth, approximately 20-25% of the variability in residual lung volume can be explained by developmental factors; (7) among high altitude rural and urban natives, it appears that approximately 20-25% of the variability in residual lung volume at high altitude can be explained by genetic traits associated with skin reflectance and genetic traits shared by siblings; and (8) vital capacity, but not the residual lung volume, is inversely related to occupational activity level. Together these data suggest that the attainment of vital capacity at high altitude is influenced more by environmental factors, such as occupational activity level, and body composition than developmental acclimatization. On the other hand, the attainment of an enlarged residual volume is related to both developmental acclimatization and genetic factors. Am. J. Hum. Biol. 9:191-203, 1997. © 1997 Wiley-Liss, Inc., (Copyright © 1997 Wiley-Liss, Inc.)

The aerobic capacity of 268 subjects (158 males and 110 females) was evaluated in La Paz, Bolivia situated at 3,750 m. The sample included 1) 39 high altitude rural natives (all male); 2) 67 high altitude urban natives (32 male, 35 female); 3) 69 Bolivians of foreign ancestry acclimatized to high altitude since birth (37 male, 32 female); 4) 50 Bolivians of foreign ancestry acclimatized to high altitude during growth (25 male, 25 female); and 5) 42 non-Bolivians of either European or North American ancestry acclimatized to high altitude during adulthood (25 male, 18 female). Data analyses indicate that 1) high altitude urban natives, acclimatized to high altitude since birth or during growth, attained higher aerobic capacity than subjects acclimatized to high altitude during adulthood; 2) age at arrival to high altitude is inversely related to maximum oxygen consumption (VO2 max) expressed in terms L/min or ml/min/kg of lean body mass, but not in terms of ml/min/kg of body weight; 3) among subjects acclimatized to high altitude during growth, approximately 25% of the variability in aerobic capacity can be explained by developmental factors; 4) as inferred from evaluations of skin color reflectance and sibling similarities, approximately 20 to 25% of the variability in aerobic capacity at high altitude can be explained by genetic factors; 5) except among the non-Bolivians acclimatized to high altitude during adulthood, the aerobic capacity of individuals with high occupational activity level is equal to the aerobic capacity of high altitude rural natives; and 6) the relationship between occupational activity level and aerobic capacity is much greater among subjects acclimatized to high altitude before the age of 10 years than afterwards. Together these data suggest that the attainment of normal aerobic capacity at high altitude is related to both developmental acclimatization and genetic factors but its expression is highly mediated by environmental factors, such as occupational activity level and body composition.

The relationship of body fat distribution to serum cholesterol levels was evaluated in a sample of 3,040 Mexican Americans 18-74 years of age from the Hispanic Health and Nutrition Examination Survey (HHANES) conducted from 1982-1984. Fat distribution was determined by the ratio of trunk to extremity skinfold thicknesses, while the sum of skinfold thicknesses was used as an indicator of total body fat. Results of this study indicate that: 1) Mexican Americans are significantly fatter and have a higher trunk/extremity skinfold ratio than U.S. standards; 2) despite their higher level of total body fat and truncal fat, Mexican Americans have lower serum cholesterol levels than U.S. standards; 3) Mexican American males at the same percentile level of fatness or trunk/extremity skinfold ratio have significantly higher serum cholesterols than females, despite the fact that females have higher absolute values of fat and truncal fat than males; 4) among Mexican American males the association between truncal fat distribution and hypercholesteremia increases with level of fatness. In other words, in Mexican American males the association of truncal fat distribution with hypercholesteremia is accentuated by obesity. © 1994 Wiley-Liss, Inc., (Copyright © 1994 Wiley-Liss, Inc., A Wiley Company.)