Evaluation of the therapeutic efficacy of praziquantel against schistosomes in seven countries with ongoing large-scale deworming programs

The World Health Organization (WHO) recommends periodic assessment of the therapeutic efficacy of praziquantel (PZQ) to detect reduced efficacy that may arise from drug resistance in schistosomes. In this multi-country study (2014), we assessed the therapeutic efficacy of a single oral dose of PZQ (40 mg/kg) against Schistosoma mansoni (Brazil, Cameroon, Ethiopia, Mali, Madagascar and Tanzania), S. haematobium (Cameroon, Ethiopia, Mali, Tanzania and Zanzibar) and S. japonicum (the Philippines) infections in school-aged children, across a total of 12 different trials. Each trial was performed according to the standardized methodology for evaluating PZQ efficacy as described by the WHO. Overall, therapeutic efficacy, measured as the reduction in arithmetic mean of schistosome egg counts following drug administration (egg reduction rate; ERR), was high for all three schistosome species (S. mansoni: 93.4% (95%CI: 88.8-96.8); S. haematobium: 97.7% (95%CI: 96.5-98.7) and S. japonicum: 90.0% (95%CI: 68.4-99.3). At the trial level, therapeutic efficacy was satisfactory (point estimate ERR >= 90%) for all three Schistosoma species with the exception of S. mansoni in Cameroon where the ERR was 88.5% (95%CI: 79.0-95.1). Furthermore, we observed that in some trials individual drug response could vary significantly (wide 95%CI) and that few non-responsive individuals could significantly impact ERR point estimates. In conclusion, these results do not suggest any established reduced efficacy of the standard PZQ treatment to any of the three schistosome species within these countries. Nevertheless, the substantial degree of variation in individual responses to treatment in some countries underpins the need for future monitoring. The reported ERR values serve as reference values to compare with outcomes of future PZQ efficacy studies to ensure early detection of reduced efficacies that could occur as drug pressure continues increase. Finally, this study highlights that 95%CI should be considered in WHO guidelines to classify the therapeutic efficacy of PZQ

Evaluation of the Therapeutic Efficacy of Praziquantel Against Schistosomes in Seven Countries with Ongoing Large-Scale Deworming Programs

The World Health Organization (WHO) recommends periodic assessment of the therapeutic efficacy of praziquantel (PZQ) to detect reduced efficacy that may arise from drug resistance in schistosomes. In this multi-country study (2014), we assessed the therapeutic efficacy of a single oral dose of PZQ (40 mg/kg) against Schistosoma mansoni (Brazil, Cameroon, Ethiopia, Mali, Madagascar and Tanzania), S. haematobium (Cameroon, Ethiopia, Mali, Tanzania and Zanzibar) and S. japonicum (the Philippines) infections in school-aged children, across a total of 12 different trials. Each trial was performed according to the standardized methodology for evaluating PZQ efficacy as described by the WHO. Overall, therapeutic efficacy, measured as the reduction in arithmetic mean of schistosome egg counts following drug administration (egg reduction rate; ERR), was high for all three schistosome species (S. mansoni: 93.4% (95%CI: 88.8-96.8); S. haematobium: 97.7% (95%CI: 96.5-98.7) and S. japonicum: 90.0% (95%CI: 68.4-99.3). At the trial level, therapeutic efficacy was satisfactory (point estimate ERR ≥90%) for all three Schistosoma species with the exception of S. mansoni in Cameroon where the ERR was 88.5% (95%CI: 79.0-95.1). Furthermore, we observed that in some trials individual drug response could vary significantly (wide 95%CI) and that few non-responsive individuals could significantly impact ERR point estimates. In conclusion, these results do not suggest any established reduced efficacy of the standard PZQ treatment to any of the three schistosome species within these countries. Nevertheless, the substantial degree of variation in individual responses to treatment in some countries underpins the need for future monitoring. The reported ERR values serve as reference values to compare with outcomes of future PZQ efficacy studies to ensure early detection of reduced efficacies that could occur as drug pressure continues increase. Finally, this study highlights that 95%CI should be considered in WHO guidelines to classify the therapeutic efficacy of PZQ

"Half plate of rice to a male casual sexual partner, full plate belongs to the husband": Findings from a qualitative study on sexual behaviour in relation to HIV and AIDS in northern Tanzania

A thorough understanding of the contexts of sexual behaviour of the people who are vulnerable to HIV infection is an important component in the battle against AIDS epidemic. We conducted a qualitative study to investigate perceptions, attitudes and practices of sexually active people in three districts of northern Tanzania with the view of collecting data to inform the formulation of appropriate complementary interventions against HIV and AIDS in the study communities. We conducted 96 semi-structured interviews and 48 focus group discussions with sexually active participants (18-60 years of age) who were selected purposively in two fishing and one non-fishing communities. The study revealed a number of socio-economic and cultural factors which act as structural drivers of HIV epidemic. Mobility and migration were mentioned to be associated with the risk of HIV acquisition and transmission. Sexual promiscuous behaviour was common in all study communities. Chomolea, (a quick transactional sex) was reported to exist in fishing communities, whereas extramarital sex in the bush was reported in non-fishing community which was predominantly Christian and polygamous. Traditional practices such as Kusomboka (death cleansing through unprotected sex) was reported to exist. Other risky sexual behaviour and traditional practices together with their socio-economic and cultural contexts are presented in details and discussed. Knowledge of condom was low as some people mistook them for balloons to play with and as decorations for their living rooms. Acute scarcity of condoms in some remote areas such as vizingani (fishing islands) push some people to make their own condoms locally known as kondomu za pepsi using polythene bags. HIV prevention efforts can succeed by addressing sexual behaviour and its socio-economic and cultural contexts. More innovative, interdisciplinary and productive structural approaches to HIV prevention need to be developed in close collaboration with affected communities and be closely related to policy-making and implementation; to go beyond the limited success of traditional behavioural and biomedical interventions to particularly address the underlying social and structural drivers of HIV risk and vulnerability in the study communities

A Multicentre Randomized Controlled Trial of the Efficacy and Safety of Single-Dose Praziquantel at 40 mg/kg vs. 60 mg/kg for Treating Intestinal Schistosomiasis in the Philippines, Mauritania, Tanzania and Brazil

Control of urinary and intestinal schistosomiasis is based on mass administration of praziquantel at the World Health Organization (WHO) recommended dose of 40 mg/kg, though some countries use 60 mg/kg. This multi-country randomized clinical trial compared the efficacy (cure and egg reduction rates three weeks post-treatment) and safety of these two doses for treating intestinal schistosomiasis in 856 patients in Brazil, Mauritania and Tanzania (Schistosoma mansoni), and The Philippines (S. japonicum). Transmission and infection intensities varied across the sites, but there was no bias or heterogeneity in efficacy outcomes. The two doses are equally effective in curing intestinal schistosomiasis; the higher dose may be less well tolerated, though effects are generally mild and transient. In endemic areas people can be re-infected; one year post-treatment patients on 60 mg/kg had fewer re-infections but this finding is difficult to explain. This study was conducted to respond to the demand for evidence about the dose of praziquantel when deployed in endemic countries. The results, along with those of systematic reviews, support the current WHO recommendation for using praziquantel at 40 mg/kg and should inform policy decisions in countries. The Philippines has already changed from 60 to 40 mg/kg after this study

Malaria and Helminth Co-infections in School and Preschool Children: A Cross-sectional Study in Magu district, north-Western Tanzania.

Malaria, schistosomiasis and soil transmitted helminth infections (STH) are important parasitic infections in Sub-Saharan Africa where a significant proportion of people are exposed to co-infections of more than one parasite. In Tanzania, these infections are a major public health problem particularly in school and pre-school children. The current study investigated malaria and helminth co-infections and anaemia in school and pre-school children in Magu district, Tanzania. School and pre-school children were enrolled in a cross-sectional study. Stool samples were examined for Schistosoma mansoni and STH infections using Kato Katz technique. Urine samples were examined for Schistosoma haematobium using the urine filtration method. Blood samples were examined for malaria parasites and haemoglobin concentrations using the Giemsa stain and Haemoque methods, respectively. Out of 1,546 children examined, 1,079 (69.8%) were infected with one or more parasites. Malaria-helminth co-infections were observed in 276 children (60% of all children with P. falciparum infection). Malaria parasites were significantly more prevalent in hookworm infected children than in hookworm free children (p = 0.046). However, this association was non-significant on multivariate logistic regression analysis (OR = 1.320, p = 0.064). Malaria parasite density decreased with increasing infection intensity of S. mansoni and with increasing number of co-infecting helminth species. Anaemia prevalence was 34.4% and was significantly associated with malaria infection, S. haematobium infection and with multiple parasite infections. Whereas S. mansoni infection was a significant predictor of malaria parasite density, P. falciparum and S. haematobium infections were significant predictors of anaemia. These findings suggest that multiple parasite infections are common in school and pre-school children in Magu district. Concurrent P. falciparum, S. mansoni and S. haematobium infections increase the risk of lower Hb levels and anaemia, which in turn calls for integrated disease control interventions. The associations between malaria and helminth infections detected in this study need further investigation

The Recognition of and Care Seeking Behaviour for Childhood Illness in Developing Countries: A Systematic Review

Background: Pneumonia, diarrhoea, and malaria are among the leading causes of death in children. These deaths are largely preventable if appropriate care is sought early. This review aimed to determine the percentage of caregivers in low- and middle-income countries (LMICs) with a child less than 5 years who were able to recognise illness in their child and subsequently sought care from different types of healthcare providers. Methods and Findings: We conducted a systematic literature review of studies that reported recognition of, and/or care seeking for episodes of diarrhoea, pneumonia or malaria in LMICs. The review is registered with PROSPERO (registration number: CRD42011001654). Ninety-one studies met the inclusion criteria. Eighteen studies reported data on caregiver recognition of disease and seventy-seven studies on care seeking. The median sensitivity of recognition of diarrhoea, malaria and pneumonia was low (36.0%, 37.4%, and 45.8%, respectively). A median of 73.0% of caregivers sought care outside the home. Care seeking from community health workers (median: 5.4% for diarrhoea, 4.2% for pneumonia, and 1.3% for malaria) and the use of oral rehydration therapy (median: 34%) was low. Conclusions: Given the importance of this topic to child survival programmes there are few published studies. Recognition of diarrhoea, malaria and pneumonia by caregivers is generally poor and represents a key factor to address in attempts to improve health care utilisation. In addition, considering that oral rehydration therapy has been widely recommended for over forty years, its use remains disappointingly low. Similarly, the reported levels of care seeking from community health workers in the included studies are low even though global action plans to address these illnesses promote community case management. Giving greater priority to research on care seeking could provide crucial evidence to inform child mortality programmes

Antimicrobial susceptibility of Shigella flexneri and S. dysenteriae isolated from stool specimens of patients with bloody diarrhoea in Mwansa, Tanzania

No Abstract. Tanzania Health Research Bulletin Vol. 9 (3) 2007: pp.186-18