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A visual dosing aid for first-line pediatric antiretroviral treatment in resource-poor settings
The visual dosing aid (VDA) was developed to facilitate dosing calculations in response to children's; growth and weight during antiretroviral treatment. The theoretical accuracy of the VDA was assessed using anthropometric data from 55 children receiving care in the USA and 324 children in the Democratic Republic of the Congo. The VDA dose was similar to the WHO recommended dose. A potentially significant relative dosing difference of >or=20% occurred in <3% of children for NVP, AZT and d4T, but was observed in 20% for 3TC, overdosing being more frequent. The VDA compared well with generic pediatric fixed dose combination tablets. Results did not differ between sites. The VDA enables accurate dosing of pediatric ART in distinct populations and could facilitate roll-out of pediatric ART in resource-poor settings
Modeling interval-censored, clustered cow udder quarter infection times through the shared gamma frailty model
Time to infection data are often simultaneously clustered and interval-censored. The time to infection is not known exactly; it is only known to have occurred within a certain interval. Moreover, observations often occur in clusters. Consequently, the independence assumption does not hold. Here we propose an extension of the shared gamma frailty model to handle the interval censoring and clustering simultaneously. We show that the frailties can be integrated out analytically, allowing maximization of the marginal likelihood to obtain parameter estimates. We apply our method to a longitudinal study with periodic follow-up on dairy cows to investigate the effect of parameters at the cow level (e.g., parity) and also parameters that can change within the cow (e.g., front or rear udder quarter) on time to infection. Dairy cows were assessed approximately monthly for the presence of a bacterial infection at the udder-quarter level, thus generating interval-censored data. Obviously, the four udder quarters are clustered within the cow. Based on simulations, we find that ignoring the interval-censored nature of the data can lead to biased parameter estimates
T. cruzi OligoC-TesT: a simplified and standardized polymerase chain reaction format for diagnosis of Chagas disease
BACKGROUND: PCR has evolved into one of the most promising tools for T. cruzi detection in the diagnosis and control of Chagas disease. However, general use of the technique is hampered by its complexity and the lack of standardization. METHODOLOGY: We here present the development and phase I evaluation of the T. cruzi OligoC-TesT, a simple and standardized dipstick format for detection of PCR amplified T. cruzi DNA. The specificity and sensitivity of the assay were evaluated on blood samples from 60 Chagas non-endemic and 48 endemic control persons and on biological samples from 33 patients, 7 reservoir animals, and 14 vectors collected in Chile. PRINCIPAL FINDINGS: The lower detection limits of the T. cruzi OligoC-TesT were 1 pg and 1 to 10 fg of DNA from T. cruzi lineage I and II, respectively. The test showed a specificity of 100% (95% confidence interval [CI]: 96.6%-100%) on the control samples and a sensitivity of 93.9% (95% CI: 80.4%-98.3%), 100% (95% CI: 64.6%-100%), and 100% (95% CI: 78.5%-100%) on the human, rodent, and vector samples, respectively. CONCLUSIONS: The T. cruzi OligoC-TesT showed high sensitivity and specificity on a diverse panel of biological samples. The new tool is an important step towards simplified and standardized molecular diagnosis of Chagas disease
Zoonotic tuberculosis and brucellosis in Africa: neglected zoonoses or minor public-health issues? The outcomes of a multi-disciplinary workshop
Late in 2007, veterinary, medical and anthropological professionals from Europe and Africa met in a 2-day workshop in Pretoria, South Africa, to evaluate the burden, surveillance and control of zoonotic tuberculosis and brucellosis in sub-Saharan Africa. Keynote presentations reviewed the burden of these diseases on human and livestock health, the existing diagnostic tools, and the available control methods. These presentations were followed by group discussions and the formulation of recommendations.
The presence of Mycobacterium bovis and Brucella spp. in livestock was considered to be a serious threat to public health, since livestock and animal products are the only source of such infections in human beings. The impact of these pathogens on human health appears to be relatively marginal, however, when compared with Mycobacterium tuberculosis infections and drug resistance, HIV and malaria. Appropriate diagnostic tools are needed to improve the detection of M. bovis and Brucella spp. in humans. In livestock, the 'test-and-slaughter' approach and the pasteurization of milk, which have been used successfully in industrialized countries, might not be the optimal control tools in Africa. Control strategies should fit the needs and perceptions of local communities. Improved intersectoral and international collaboration in surveillance, diagnosis and control, and in the education of medical and veterinary personnel, are advocated
Effectiveness of quinine versus artemether-lumefantrine for treating uncomplicated falciparum malaria in Ugandan children: randomised trial
OBJECTIVE: To compare the effectiveness of oral quinine with that of artemether-lumefantrine in treating uncomplicated malaria in children. DESIGN: Randomised, open label effectiveness study. SETTING: Outpatient clinic of Uganda's national referral hospital in Kampala. PARTICIPANTS: 175 children aged 6 to 59 months with uncomplicated malaria. INTERVENTIONS: Participants were randomised to receive oral quinine or artemether-lumefantrine administered by care givers at home. MAIN OUTCOME MEASURES: Primary outcomes were parasitological cure rates after 28 days of follow-up unadjusted and adjusted by genotyping to distinguish recrudescence from new infections. Secondary outcomes were adherence to study drug, presence of gametocytes, recovery of haemoglobin concentration from baseline at day 28, and safety profiles. RESULTS: Using survival analysis the cure rate unadjusted by genotyping was 96% for the artemether-lumefantrine group compared with 64% for the quinine group (hazard ratio 10.7, 95% confidence interval 3.3 to 35.5, P=0.001). In the quinine group 69% (18/26) of parasitological failures were due to recrudescence compared with none in the artemether-lumefantrine group. The mean adherence to artemether-lumefantrine was 94.5% compared with 85.4% to quinine (P=0.0008). Having adherence levels of 80% or more was associated with a decreased risk of treatment failure (0.44, 0.19 to 1.02, P=0.06). Adverse events did not differ between the two groups. CONCLUSIONS: The effectiveness of a seven day course of quinine for the treatment of uncomplicated malaria in Ugandan children was significantly lower than that of artemether-lumefantrine. These findings question the advisability of the recommendation for quinine therapy for uncomplicated malaria in Africa. TRIAL REGISTRATION: ClinicalTrials.gov NCT00540202
Dietary behaviour, food and nutrient intake of pregnant women in a rural community in Burkina Faso
The aim of this study was to assess potential changes in dietary habits during pregnancy in a rural community in Houndé district, Burkina Faso. In-depth interviews were performed on a random sample of 37 pregnant women in order to analyse specific perceptions and attitudes regarding food consumption during pregnancy. In addition to this, an interactive 24-h recall survey was used to compare the food intake of 218 pregnant and 176 non-pregnant women. The majority of interviewees reported dietary restrictions during pregnancy but no consistent pattern of avoided food types was found. Most of the mentioned `forbidden' foods were in related to physical discomfort during gestation. Interviewees also admitted to ignoring culturally determined food prohibitions/prescriptions. No differences were observed in food intake, food choice and nutrient intake between the group of pregnant and non-pregnant women. During the third trimester of gestation women did not show any major differences in food and nutrient intake compared with women from the first/second trimester. The mean nutrient intakes were found to be insufficient compared with the recommended daily allowances, especially for pregnant women. In conclusion, pregnant women in this rural area of Burkina Faso do not seem to restrict their diet significantly during pregnancy. The additional nutritional requirements of pregnancy are not accounted for in their dietary practises
Pediatric HIV: new opportunities to treat children
BACKGROUND: Treating HIV-infected children remains a challenge due to a lack of treatment options, appropriate drug formulations and, in countries with limited resources, insufficient access to diagnostic tests and treatment. OBJECTIVE: To summarize current data concerning new opportunities to improve the treatment of HIV-infected children. METHODS: This review includes data from the most recently published peer-reviewed publications, guidelines or presentations at international meetings concerning new ways to treat HIV-infected children. RESULTS/CONCLUSIONS: New WHO guidelines recommend starting combination antiretroviral treatment in all infants aged < 1 year. Although this is common practice in some high-income countries, implementation of these recommendations in countries with limited resources is still a challenge. There is still an important gap between the availability of licensed drugs in children compared with adults. There remains a need for further pharmacokinetic studies, and for more pediatric formulations of antiretroviral drugs with improved palatability