[Soil-transmitted nematode infections and influencing factors in pupils from rural areas of Yi Ethnicity in Butuo County, Sichuan Province].

OBJECTIVE: To understand the current situation of soil-transmitted nematode infections and influencing factors of pupils in rural areas of Yi Ethnicity in Butuo County, Sichuan Province, so as to provide the evidence for the prevention and control of soil-transmitted nematode infections. METHODS: In 2016, the pupils of 2 villages in Butuo County were selected by the multi-stage random sampling method, and the relevant information was obtained by questionnaires, including social demographic information, diet and hygiene habits and acknowledge of parasitic disease prevention. The soil-transmitted nematode infections were examined by Kato-Katz technique. The results were statistically analyzed by the single factor analysis and multivariate logistic regression methods. RESULTS: A total of 160 pupils were investigated in this survey. The soil-transmitted nematodes included Ascaris lumbricoides, Trichuris trichiura and hookworm. The overall infection rate was 89.38%, and the multi-infection rate was 54.55%. The infection rates of A. lumbricoides and T. trichiura were higher. The infection densities were mild (75.68%) or moderate (22.97%). The logistic regression analysis showed that the protective factor of soil-transmitted nematode infections was the knowledge about correct diet and health habits notified by teachers (OR = 0.67), but the risk factor was drinking unboiled water (OR = 19.26). CONCLUSIONS: The infection rate of nematodes is still high in the pupils in rural areas of Yi Ethnicity in Butuo County, Sichuan Province. Therefore, we should strengthen the prevention and control of soil-transmitted nematode infections, especially A. lumbricoides and T. trichiura infections, and mostly develop the teachers'function in health education.

Intestinal parasitic infections amongst Orang Asli (indigenous) in Malaysia: has socioeconomic development alleviated the problem?

Orang Asli are the indigenous minority peoples of peninsular Malaysia. Despite proactive socioeconomic development initiated by the Malaysian Government in upgrading the quality of life of the Orang Asli communities since 1978, they still remained poor with a current poverty rate of 76.9%. Poverty exacerbates the health problems faced by these communities which include malnourishment, high incidences of infectious diseases (eg. tuberculosis, leprosy, malaria) and the perpetual problem with intestinal parasitic infections. Studies reported that the mean infection rate of intestinal parasitic infections in Orang Asli communities has reduced from 91.1% in 1978, to 64.1% in the subsequent years. Although the results was encouraging, it has to be interpreted with caution because nearly 80% of studies carried out after 1978 still reported high prevalence (i.e. >50%) of soil-transmitted helminthiases (STH) among Orang Asli communities. Prior to 1978, hookworm infection is the most predominant STH but today, trichuriasis is the most common STH infections. The risk factors for intestinal parasitic infections remained unchanged and studies conducted in recent years suggested that severe STH infections contributed to malnutrition, iron deficiency anaemia and low serum retinol in Orang Asli communities. In addition, STH may also contribute to poor cognitive functions and learning ability. Improvements in socioeconomic status in Malaysia have shown positive impact on the reduction of intestinal parasitic infections in other communities however, this positive impact is less significant in the Orang Asli communities. In view of this, a national parasitic infections baseline data on morbidity and mortality in the 18 subgroups of Orang Asli, will assist in identifying intervention programmes required by these communities. It is hope that the adoption of strategies highlighted in the World Health Organisation- Healthy Village Initiatives (WHO-HVI) into Orang Asli communities will ensure the whole mechanism of delivery and empowerment by the government agencies become more efficient and productive in alleviating intestinal parasitic infections in these communities.

Targeted chemotherapy for parasite infestations in rural black preschool children.

OBJECTIVE: To investigate whether targeted chemotherapy can reduce parasite prevalence rates in rural black preschool children. DESIGN: The study consisted of a before/after trial. Stool and urine samples were analysed on four occasions over a 21-week period. SETTING: Crèches in two rural areas of southern KwaZulu/Natal (coastal and inland). PATIENTS: Two hundred children of 4-6 years of age attending 19 crèches in the area. INTERVENTION: Targeted chemotherapy using albendazole for nematode infestations, praziquantel for trematode and cestode infestations and metronidazole for protozoal infections was administered twice at an interval of 14 weeks. MAIN OUTCOME MEASURE: Prevalence rates. RESULTS: The prevalence of Ascaris lumbricoides, Trichuris trichiura and Necator americanus infestation decreased significantly after treatment. Reinfestation rates 12 weeks after treatment were 16% for A. lumbricoides, 33% for T. trichiura, 24% for Giardia lamblia and 3% for N. americanus. No reinfestation was noted for Schistosoma haematobium, Hymenolepsis or Taenia species. CONCLUSION: The study suggests that parasite prevalence rates in children can be reduced by the administration of appropriate chemotherapy at regular intervals. However, the provision of clean water and adequate sewerage facilities remains a high priority for black communities living in rural areas of South Africa.