Lahar inundated, modified, and preserved 1.88 Ma early hominin (OH24 and OH56) Olduvai DK site.

Archaeological excavations at the DK site in the eastern Olduvai Basin, Tanzania, age-bracketed between ∼1.88 Ma (Bed I Basalt) and ∼1.85 Ma (Tuff IB), record the oldest lahar inundation, modification, and preservation of a hominin "occupation" site yet identified. Our landscape approach reconstructs environments and processes at high resolution to explain the distribution and final preservation of archaeological materials at the DK site, where an early hominin (likely Homo habilis) assemblage of stone tools and bones, found close to hominin specimens OH24 and OH56, developed on an uneven heterogeneous surface that was rapidly inundated by a lahar and buried to a depth of 0.4-1.2 m (originally ∼1.0-2.4 m pre-compaction). The incoming intermediate to high viscosity mudflow selectively modified the original accumulation of "occupation debris," so that it is no longer confined to the original surface. A dispersive debris "halo" was identified within the lahar deposit: debris is densest immediately above the site, but tails off until not present >150 m laterally. Voorhies indices and metrics derived from limb bones are used to define this dispersive halo spatially and might indicate a possible second assemblage to the east that is now eroded away. Based upon our new data and prior descriptions, two possibilities for the OH24 skull are suggested: it was either entrained by the mudflow from the DK surface and floated due to lower density toward its top, or it was deposited upon the solid top surface after its consolidation. Matrix adhering to material found in association with the parietals indicates that OH56 at least was relocated by the mudflow.

Drug dispensing practices during implementation of artemisinin-based combination therapy at health facilities in rural Tanzania, 2002-2005.

OBJECTIVE: To assess the degree to which policy changes to artemisinin-based combination therapies (ACTs) as first-line treatment for uncomplicated malaria translate into effective ACT delivery. METHODS: Prospective observational study of drug dispensing practices at baseline and during the 3 years following introduction of ACT with sulfadoxine-pyrimethamine (SP) plus artesunate (AS) in Rufiji District, compared with two neighbouring districts where SP monotherapy remained the first-line treatment, was carried out. Demographic and dispensing data were collected from all patients at the dispensing units of selected facilities for 1 month per quarter, documenting a total of 271, 953 patient encounters in the three districts. RESULTS: In Rufiji, the proportion of patients who received a clinical diagnosis of malaria increased from 47.6% to 57.0%. A majority (75.9%) of these received SP + AS during the intervention period. Of patients who received SP + AS, 94.6% received the correct dose of both. Among patients in Rufiji who received SP, 14.2% received SP monotherapy, and among patients who received AS, 0.3% received AS monotherapy. CONCLUSIONS: The uptake of SP + AS in Rufiji was rapid and sustained. Although some SP monotherapy occurred, AS monotherapy was rare, and most received the correct dose of both drugs. These results suggest that implementation of an artemisinin combination therapy, accompanied by training, job aids and assistance in stock management, can rapidly increase access to effective antimalarial treatment.

Tuberculosis in HIV-infected Tanzanian children below 14 years.

OBJECTIVE: Tuberculosis (TB)-human immunodeficiency virus (HIV) co-infection is an important public health problem. Diagnosis of TB in children usually follows discovery of an adult case, and relies on clinical presentation, sputum examination and chest radiograph. However, clinical features are non-specific, chest radiographs are difficult to interpret, and routine laboratory tests are not helpful. The aim of the current study was to determine the prevalence of TB in HIV-infected children below 14 years attending a tertiary hospital. METHODS: A cross-sectional study was conducted in HIV-infected children below 14 years of age at Muhimbili National Hospital, in Dar es Salaam, Tanzania, between July 2008 and January 2009. Information on socio-demographic and anthropometric characteristics was collected using a structured questionnaire. Following assessment of clinical presentation, physical examination, tuberculin skin test, and chest radiograph were performed for each child. Two consecutive sputum specimens and blopd sample were collected for microscopy and culture, and CD4 T-lymphocyte percentage test, respectively. Chi-square test was used to compare differences in proportions. Odds ratio (OR) and their 95% confidence interval (CI) are presented as the risk estimator. RESULTS: Of 182 HIV-infected children enrolled in the study, 104 (57.1%) were males. Overall, thirty-seven (20.3%) children had TB. The prevalence of TB was highest in males (78.4%) compared to females (p = 0.003). There was a higher proportion of TB (45.9%) in the age group below 24 months compared to other age groups (p = 0.001). Male gender, history of positive TB contact and severe immunosuppression were found to be significant risk factors for TB while use of antiretroviral therapy was found to be associated with decreased risk for TB. CONCLUSIONS: One-fifth of children had TB/HIV co-infection. Presence of four or more clinical manifestations and a low CD4+ T-lymphocyte percentage can be used to predict active TB in HIV-infected children.

Community directed approach beyond ivermectin in Tanzania: a promising mechanism for the delivery of complex health interventions.

The Community Directed Intervention (CDI) is currently used for Ivermectin distribution for the treatment of onchocerciasis in Africa. This study was carried out to determine the extent to which the CDI process can be used for the delivery of other health interventions with different degrees of complexity. The study was conducted in five districts of Kilosa, Muheza, Lushoto, Korogwe and Ulanga in Tanzania and involved communities, health facility and district healthcare providers. Implementation of CDI across these health interventions involved addressing six major processes, namely, stakeholder processes, health system dynamics, engaging communities, empowering communities, engaging CDI implementers and broader system effects. Community and health systems changes were triggered, such that the inherent value of community involvement and empowerment could be internalized by communities and health workers, leading to a more receptive health system. The CDI process was accepted at the community levels as many were willing and ready to adopt the approach. Health workers at community levels were readily available and supportive of the process. Additionally, noted were the verified willingness and ability of community implementers to deliver multiple interventions; confirmed efficiency of CDI leading to cost savings at health systems level; increasing interest of the health system in CDI; interest of health workers in the process of integrated planning. However, there were factors that may have a negative influence on the CDI process. Drug and supply policy for CDI process was lacking at the national and district levels and the presence of parallel community-based programmes that provide financial incentives for community members to run them discouraged Community-directed distributors who in most cases are volunteers. In conclusion, the results have clearly and evidently demonstrated the potential of CDI approach for effectively and efficiently control of other diseases such as malaria, tuberculosis and childhood illnesses. The study has provided unique information on the feasibility and effectiveness of integrated delivery of interventions at the community level.

Community directed interventions for malaria, tuberculosis and vitamin A in onchocerciasis endemic districts of Tanzania.

In recognising the success attained through community-directed treatment with Ivermectin, there has been a growing interest to use a similar approach for delivery of interventions against other communicable diseases. This study was conducted in 2007 to evaluate the impact of community directed intervention (CDI) on delivering five health interventions namely Vitamin A supplementation (VAS), community-directed treatment with Ivermectin (CDTi), distribution of insecticide-treated nets (ITN), directly observed treatment of tuberculosis (DOTS), and home-based management of malaria (HMM). The study was carried out in onchocerciasis endemic districts of Kilosa, Muheza, Lushoto, Korogwe and Ulanga districts in Tanzania. A total of 250 households were involved in the study for the period of two years. During the first year, one new intervention was added in each study district. A second new intervention was then added in the same manner during the second study year. In the control district all interventions, with the exception of Ivermectin distribution, continued to be delivered in the traditional manner throughout the study period. Results showed that Ivermectin treatment coverage in the CDI districts (88%) was significantly (P<0.005) higher than in the control district (77%). The coverage of VAS was 84 +/- 7%, showing very little difference between control and intervention districts (P>0.05). The DOTS treatment completion rate was observed only in Korogwe where 4 out 7 patients had completed their treatment. The proportions of pregnant women and <5 years children sleeping under ITN in the CDI districts (range: 83-100%) were significantly higher (P< 0.05) than those in the control district (40-43%). There was also a higher proportion of malaria cases referred in the intervention districts (42%) than in the control district (21%) (P<0.005). Likewise, the proportion of <5 years children who were presumptively diagnosed with malaria and received appropriated treatment within 24 hours in the intervention districts (17-29%) was higher than those in the control district (4%) (P<0.005). The costs incurred per integrated programme in the intervention districts were much lower than those in the control district. In conclusion, our results showed higher coverage of interventions in the CDI districts without necessarily increasing the cost.

Aflatoxin levels in locally grown maize from Makueni District, Kenya.

OBJECTIVES: Investigations were carried out to determine aflatoxin levels in household maize in Makueni District and to correlate aflatoxin levels to maize drying and storage practices. Also, aflatoxin exposure in villages that reported aflatoxicosis cases in 2005 was compared with that in villages that did not report cases to assess whether aflatoxin exposure levels could be used to identify high-risk villages for targeted prevention interventions. DESIGN: A cross-sectional study. SETTING: Three divisions of Makueni district, Kibwezi, Makindu and Mtito Andei in Eastern Province, Kenya. SUBJECTS: Ninety six households were surveyed, and 104 maize samples were analysed for total aflatoxin levels from June to July 2005. The households were selected from high and low aflatoxicosis risk areas. RESULTS: Out of the 104 maize samples collected from 96 households, 37 (35.5%) had aflatoxin levels above the World Health Organisation (WHO) recommended maximum limit of 20 ppb. All of these samples were homegrown or purchased. Twenty one samples (20.1%) had levels above 100 ppb. Eleven (10.6%) had extremely high levels above 1000 ppb. No relief supply maize had aflatoxin levels above the WHO maximum limit. CONCLUSION: High levels of aflatoxin in homegrown and purchased maize suggested that aflatoxin exposure was widespread.

Fever treatment and household wealth: the challenge posed for rolling out combination therapy for malaria.

OBJECTIVE: To investigate the variation in malaria parasitaemia, reported fever, care seeking, antimalarials obtained and household expenditure by socio-economic status (SES), and to assess the implications for ensuring equitable and appropriate use of antimalarial combination therapy. METHODS: A total of 2,500 households were surveyed in three rural districts in southern Tanzania in mid-2001. Blood samples and data on SES were collected from all households. Half the households completed a detailed questionnaire on care seeking and treatment costs. Households were categorised into SES thirds based on an index of household wealth derived using principal components analysis. RESULTS: Of individuals completing the detailed survey, 16% reported a fever episode in the previous 2 weeks. People from the better-off stratum were significantly less likely to be parasitaemic, and significantly more likely to obtain antimalarials than those in the middle or poor stratum. The better treatment obtained by the better off led them to spend two to three times more than the middle and poor third spent. This reflected greater use of non-governmental organisation (NGO) facilities, which were the most expensive source of care, and higher expenditure at NGO facilities and drug stores. CONCLUSION: The coverage of appropriate malaria treatment was low in all SES groups, but the two poorer groups were particularly disadvantaged. As countries switch to antimalarial combination therapy, distribution must be targeted to ensure that the poorest groups fully benefit from these new and highly effective medicines.