Household and community variations and nested risk factors for diarrhoea prevalence in southern Malawi: a binary logistic multi-level analysis.

This paper examines household and community-level influences on diarrhoeal prevalence in southern Malawi. A Bayesian multi-level modelling technique is used in the estimation of hierarchically built data from a survey of individuals nested within households nested within communities. Households have strong unobserved influence on diarrhoeal illness (sigma(2)(u) = 4.476; 95% CI: 2.081, 6.871). A joint Wald test of significance shows that an individual's age [chi(2)(4) = 55.921, p = 0.000] and school [chi(2)(2) = 18.203, p = 0.000] have strong influence on an individual's diarrhoeal prevalence. An individual's history of malarial-like illness also has a strong positive relationship with diarrhoeal prevalence [beta = 0.606, p = 0.000]. Household factors that influence diarrhoea include employment status of head of household [beta = -0.619, p < 0.021], maternal age [beta = -0.013, p < 0.003], and size of household [beta = -0.669, p = 0.000]. The positive relationship between diarrhoea and malaria-like episodes highlights common risk factors hence the need for common approaches to combat the diseases. Significant household effects underline the importance of household considerations in policy issues.

Care-Seeking Behaviour and Implications for Malaria Control in Southern Malawi

Although malaria is a controllable and preventable disease; it remains among the leading causes of mortality and morbidity in southern Malawi. The importance of early diagnosis and prompt treatment with hospital prescribed drugs and effective home management to control malaria is well established; however; these in part depend on how households make their decisions when family members have suffered from malaria. This study examines the behaviour of households with regard to decisions they make in managing malaria illness. Using hierarchically built data from a survey of 1;400 mothers nested within 33 communities; a series of two-level logistic regression models with Bayesian estimation was used to determine predictors of care-seeking behaviour towards malaria when a family member or a child was perceived to have malaria. The results show that most families normally visit or use medication prescribed at health facilities for both adult (80) and child (86) members when they are perceived to have malaria. The main obstacle to accessing the nearest health facility was distance and transport costs (73) and the main problems encountered at health facilities were long waiting time or absence of health workers (73) and shortage of drugs (35). Among the main predictor variables for choices of treatment for childhood malaria was the absence of a health surveillance assistant for those that visited hospitals [Beta=0.56; 95CI:-0.86;-0.26]; bought medication from open markets [Beta=0.51; 95CI:0.20;0.82]; and those that used other traditional methods or did nothing [Beta=0.70; 95CI:-0.04;1.44; p=0.06].. The results have an important role to play in the control and prevention of malaria in Malawi. The results reveal the need for increased awareness about the dangers of purchasing drugs from non-medical and/or uncertified private institutions and sources such as those found in open markets. They also show the important role of community health workers in the delivery of health systems. The study recommends empowerment of community health workers through rigorous and relevant health promotion programmes to update both their knowledge and their skills in communication and counselling

Care-Seeking Behaviour and Implications for Malaria Control in Southern Malawi

Abstract:Although malaria is a controllable and preventable disease; it remains among the leading causes of mortality and morbidity in southern Malawi. The importance of early diagnosis and prompt treatment with hospital prescribed drugs and effective home management to control malaria is well established; however; these in part depend on how households make their decisions when family members have suffered from malaria. This study examines the behaviour of households with regard to decisions they make in managing malaria illness. Using hierarchically built data from a survey of 1;400 mothers nested within 33 communities; a series of two-level logistic regression models with Bayesian estimation was used to determine predictors of care-seeking behaviour towards malaria when a family member or a child was perceived to have malaria. The results show that most families normally visit or use medication prescribed at health facilities for both adult (80) and child (86) members when they are perceived to have malaria. The main obstacle to accessing the nearest health facility was distance and transport costs (73) and the main problems encountered at health facilities were long waiting time or absence of health workers (73) and shortage of drugs (35). Among the main predictor variables for choices of treatment for childhood malaria was the absence of a health surveillance assistant for those that visited hospitals [?=0.56; 95 CI:-0.86;-0.26]; bought medication from open markets [?=0.51; 95 CI:0.20;0.82]; and those that used other traditional methods or did nothing [?=0.70; 95

Cryptosporidium infection in non-human hosts in Malawi.

Of 1346 faecal samples from the Chikwawa and Thyolo districts of Malawi, analysed for the presence of Cryptosporidium oocysts between October 2001 and May 2003, 61.3% were from cattle (29.8% of these were from calves <6 months old). Cryptosporidium oocysts were detected during all three seasons studied in Chikwawa and Thyolo. In Chikwawa, 13.6% of adult cattle and 11.7% of calves were infected, compared to 28.9% of adult cattle and 36.7% of calves in Thyolo. Dependent on season, between 7.8% and 37.7% (Chikwawa) and 16.7% and 39.3% (Thyolo) of cattle samples contained oocysts. In Chikwawa, the highest percentage of infections occurred in the cool season, whereas in Thyolo, the highest percentage of infections occurred in the dry season. Faecal samples from goats [n=225], pigs [n=92], sheep [n=6]), rabbits, guinea pigs, chickens, ducks, turkeys, doves and guinea fowls were also analysed. Up to 5.6% of goat samples contained oocysts in Chikwawa, compared to between 16.7% and 39.3% in Thyolo. Again, in Chikwawa, the highest percentage of infections occurred in the cool season and the lowest in the rainy season, whereas, in Thyolo, the highest percentage of infections occurred in the dry season and the lowest in the cool season. In pigs, more infections were detected in the dry season in Chikwawa, but infections in the cool season were similar (17.7%), whereas in Thyolo, infections occurred in all three seasons (17.9% in the rainy season, 25% in the cool season and 60% in the dry season). Of ten diarrhoeic, oocyst positive cattle faecal samples collected from Chikwawa and subjected to PCR-RFLP, four oocyst positive samples (two from heifers, one from a cow and one unknown) were amplified at an 18S rRNA and Cryptosporidium oocyst wall protein (COWP) loci. RFLP of the 18S rRNA locus indicated that Cryptosporidium parvum, Cryptosporidium hominis, Cryptosporidium bovis and/or Cryptosporidium ryanae DNA, or a mixture of them was present. Cryptosporidium parvum DNA was identified in one sample that amplified at the COWP locus, indicating the presence of the major zoonotic Cryptosporidium species in Malawi.

Incidence of cryptosporidiosis species in paediatric patients in Malawi.

We determined the incidence of cryptosporidiosis in children aged <5 years presenting with diarrhoea in an urban and rural hospital-based setting in Malawi. Stools were collected over a 22-month period during both rainy and dry seasons. A range of microscopic methods were used to determine the presence of Cryptosporidium spp. oocysts. Species determination was by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of oocyst-extracted DNA using 18S rRNA and COWP gene loci. Cryptosporidium spp. oocysts were seen in 5.9% (50/848) of samples, of which 43 amplified by PCR-RFLP indicated the following species: C. hominis, C. parvum, C. hominis/C. parvum, C. meleagridis and C. andersoni. Seven samples could not be amplified by PCR. Wider species diversity was found in the rural setting, and may be a result of increased malnutrition and zoonotic exposure in this area. Improvements in water, sanitation, household hygiene and animal control are required to reduce the incidence of infection in this population.

First report of cryptosporidiosis in paediatric patients in Swaziland.

Diarrhoeal disease is a significant cause of morbidity and mortality in many African countries, especially among the immunocompromised and the under five population. Over the last decade, the protozoan parasite Cryptosporidum spp. has been shown to be a significant cause of gastro-enetritis in the immunocompetent and immunocompromised in both the developed and developing world. This study reports the first finding of Cryptosporidum spp. oocysts in 2 of 48 (4.2%) faecal samples obtained from Swazi paediatric outpatients (two year old male and three year old female), presenting with diarrhoea at Mbabane Government Hospital between the months July-August 2003. Oocysts were detected using a standard anti-Cryptosporidium immunofluorescence and nuclear staining technique (after formal-ether concentration). Oocysts ranged in size from 4-6 microm with between 1-4 oocysts per field of view (x 400). The precise species was not determined. Further studies are required to determine the public health significance of Cryptospoirdium in Swaziland.

Problems associated with the use of pit latrines in Blantyre, Republic of Malawi.

A questionnaire and observational study was conducted to determine the problems associated with construction, design and hygiene methods used to maintain pit latrines in a high-density urban township in Malawi. The survey comprised 100 randomly selected households and the person responsible for the latrine maintenance was interviewed. Eighty-seven percent of householders used traditional latrines, 67% with earthen and 20% with concrete (i.e. sanitation platform, also known as San-plats) floors. A variety of makeshift squat-hole covers (e.g. iron sheets, rocks, cardboard) are used by those who cannot afford San-plats to reduce fly and odour problems. Most squat-hole covers were fouled with faecal matter and some presented risk of invasive injury due to sharp edges. Five households used ventilated improved latrines whilst the remaining eight per cent made use of their neighbour's latrine. Ownership of property, poverty and theft in the area significantly influenced the type and structural condition of the latrine. Walls, ceilings and doors of the superstructure comprised a mixture of miscellaneous materials (i.e. cardboard, paper, cloth, brick) making the hygienic upkeep of the latrine difficult. Cloth doors were often used for hand drying. Geographical location, such as rocky terrain with inadequate soil consolidation, and environmental conditions, such as heavy rains and floods, exacerbate structural defects. Coupled with the lack of attention afforded to the disposal of young children's faeces, wash-water and pit surcharging, the potential exists for widespread contamination of the surrounding environment and transmission of faecal-oral disease. More than half of the respondents stressed that they had not received any information regarding health education and hygienic maintenance of the latrine. As such, there is need for a hygiene education programme to promote awareness of appropriate sanitation and behavioural change. Cultural and religious factors were found not to influence latrine use.

Efficiency of wastewater treatment plants at removing Giardia sp. cysts in southern France.

A study was conducted to evaluate the removal efficiency for Giardia sp. cysts of a number of wastewater treatment plants in France. Of these, five were activated sludge systems, three were trickling filters and three were waste stabilisation pond systems. In addition, the effect upon cyst removal of disinfecting effluents prior to discharge into controlled waters by UV and chlorination was evaluated. Cysts were detected in raw wastewater at all 11 treatment plants in concentrations ranging from 130 to 41,270 cysts/litre. The removal of cysts by sewage treatment was found to range between 99.5 and 99.8% for activated sludge, 99.9 and 100% for waste stabilisation ponds, and for the trickling filter plants up to 98.3%. Despite the high removal efficiencies recorded in this study the range of cysts detected in final effluents discharged into controlled waters ranged from < 1 to 66 cysts/litre. This is undoubtedly an underestimate of actual occurrence and concentration in wastewater, given the limitations of the methods currently employed by investigators. Cysts were detected in final effluents which had been disinfected by both UV and chlorination (range 0.3-19 cysts/litre), however, it is not known whether such cysts were viable or non-viable.

Occurrence of Giardia sp. cysts and Cryptosporidium sp. oocysts in faeces from public parks in the west of Scotland.

One hundred faecal specimens, randomly collected from various locations within seven public parks in the west of Scotland, were examined for the presence of Giardia sp. cysts and Cryptosporidium sp. oocysts. Eleven percent of samples contained Giardia sp. cysts and 1% contained Cryptosporidium sp. oocysts. Occurrence data from individual parks varied from 0 to 40% for Giardia and 0 to 2.4% for Cryptosporidium. The occurrence of parasitic organisms in public parks, especially in the vicinity of children's playing areas is a matter of concern for public health officials and regulators of leisure and recreation amenities.