Childhood Cryptosporidium infection among aboriginal communities in Peninsular Malaysia.

Cryptosporidium is a coccidian parasite that is prevalent worldwide, some species of which cause morbidity in both immunocompromised and immunocompetent individuals. The prevalence and predictors of Cryptosporidium infection, and its effect on nutritional status, have recently been explored among 276 children (141 boys and 135 girls, aged 2-15 years) in aboriginal (Orang Asli) villages in the Malaysian state of Selangor. Faecal smears were examined by the modified Ziehl-Neelsen staining technique while socio-economic data were collected using a standardized questionnaire. Nutritional status was assessed by anthropometric measurements. Cryptosporidium infection, which was detected in 7.2% of the aboriginal children, was found to be significantly associated with low birthweight (≤2.5 kg), being part of a large household (with more than seven members) and prolonged breast feeding (>2 years). The output of a binary logistic regression confirmed that large household size was a significant predictor of Cryptosporidium infection (giving an odds ratio of 2.15, with a 95% confidence interval of 1.25-5.02). Cryptosporidium infection is clearly a public-health problem among the aboriginal children of Selangor, with person-to-person the most likely mode of transmission.

Species identification of intestinal microsporidia using immunofluorescence antibody assays.

Abstract. The species identification of Enterocytozoon bieneusi and Encephalitozoon intestinalis is only possible using transmission electron microscopy (TEM), mo lecular techniques and immunofluorescence antibody assays (IFA). In this study, 50 positive and 50 negative fecal specimens for microsporidial spores using the Weber modified trichrome (WMT) staining technique were examined using IFA-MAbs. Of the 100 specimens examined, the microsporidial spores identified by IFA-MAbs were Enterocytozoon Bieneusi 42 (75%) Encephalitozoon intestinalis 7 (12.5%) and mixed infections 7 (12.5%). The sensitivity and specificity of IFA-MAbs in detecting microsporidial spores were 98% and 86%, respectively. The agreement between the WMT staining technique and IFA-MAbs was statistically significant by Kappa statistics (K = 0.840; p < 0.001). E. bieneusi was the commonest Microsporidia species isolated from the studied population; the presence of microsporidial spores detected by IFA-MAbs should be confirmed by other methods.

Trichomoniasis in cosmopolitan Malaysia: is it under control or is it under diagnosed?

In a prospective, observational study, 380 women attending a family planning (LPPKN) clinic and Sexually Transmitted Diseases (STD) clinic in Kuala Lumpur between January 2008 and November 2008 were enrolled. Patient information was obtained from the medical records and patients voluntarily completed questionnaires. Three vaginal swabs from the posterior fornix were taken from each patient examined. Different staining methods and cultivation in Diamonds medium were performed on the collected samples. Study subjects recruited in this survey were mostly young, with a geometric mean ages of 37.31 years (LPPKN clinic) and 32.06 years (STD clinic). Malay, Chinese, Indians and others ethnic groups accounted for 91, 4, 2 and 3%, respectively, at the LPPKN clinic. At the STD clinic, almost all subjects were Chinese. The prevalence rate of trichomoniasis was 0.36% at the LPPKN clinic and 0.0% at the STD clinic. Our findings suggested no association between contraceptive methods used and trichomoniasis infection at the LPPKN clinic. At the STD clinic, it was found a high risk for STD acquisition was not associated with trichomoniasis positivity. The data demonstrated the prevalence of trichomoniasis was very low at LPPKN clinic and absent at STD clinic. The high prevalence rates of other STD among sex workers found in this survey suggest the need for more active interventions focused on this group.

Seroprevalence of toxoplasmosis among migrant workers from different Asian countries working in Malaysia.

A serologic study of Toxoplasma antibodies among 501 foreign migrant workers in Malaysia was conducted in a plantation and detention camp. The highest prevalence rate of 46.2% was among Nepalese workers. Statistical analysis indicated the IgG positivity rate among local residents was significantly higher than the migrants studied (p < 0.05). The IgM positivity rate showed no significant difference between the two groups (p > 0.05). No significant difference in the prevalence rate was noted between the migrants and the local workers when grouped by agricultural and non-agricultural occupations (p > 0.05). The continuous introduction of these infections may influence the epidemiology and further compromise efforts in control and prevention. It is therefore important to monitor of non-notifiable diseases.

Prevalence and distribution of soil-transmitted helminthiases among Orang Asli children living in peripheral Selangor, Malaysia.

Soil-transmitted helminthiases are a public health problem in rural communities. A cross-sectional study of the prevalence and distribution of Ascaris lumbricoides, Trichuris trichiura and hookworm was conducted in 281 Orang Asli children (aborigines) aged between 2 and 15 years, from 8 Orang Asli villages in Selangor, Malaysia. All the children were infected with soil-transmitted helminthes, with 26.3% of the children infected either with A. lumbricoides, T. trichiura or hookworm and 72.6% having mixed infection. The overall prevalences of A. lumbricoides, T. trichiura and hookworm were 61.9, 98.2 and 37.0%, respectively. Approximately 19.0, 26.0 and 3.0% of the children had severe infection of ascariasis, trichuriasis and hookworm infection, respectively. The prevalences and mean egg per gram (epg) counts for A. lumbricoides and T. trichiura were not significantly dependent on age, therefore age-dependent convexity was not seen in this study. However, the results of this study reveal an age-dependent prevalence and mean epg count in children with hookworm infection. We conclude that ascariasis, trichuriasis and hookworm infection are still prevalent and therefore a public health concern in Orang Asli communities. Severe ascariasis and trichuriasis may lead to other health and medical problems.

Giardiasis as a predictor of childhood malnutrition in Orang Asli children in Malaysia.

A cross-sectional study to examine the association of giardiasis with protein-energy malnutrition, vitamin A deficiency and iron deficiency anaemia was conducted among Orang Asli children in Selangor, Malaysia. A total of 281 children aged 2-15 years were studied. The data were collected using structured questionnaires, anthropometric measurements and laboratory analysis of blood and faecal samples. The results showed that 24.9% of the children were infected with Giardia duodenalis, while 56.5, 61.3 and 15.1% had significant underweight, stunting and wasting, respectively. Giardiasis was statistically identified as a strong predictor of significant wasting in this study population.

Efficacy of single dose albendazole on the prevalence and intensity of infection of soil-transmitted helminths in Orang Asli children in Malaysia.

The efficacy of a single-dose 400 mg albendazole to treat Ascaris, Trichuris and hookworm infection was studied in Orang Asli community. Kato-Katz examination was performed on fecal samples which were collected before treatment, 1 and 4 months after treatment. A total of 123 children were involved in all three surveys. The cure rate of Ascaris infection was 97.4% and the egg reduction after treatment was 99.9%. The cure rate for hookworm infection was 93.1% with 96.6% egg reduction. Although the cure rate was low in Trichuris infection (5.5%), egg reduction was more evident (49.1%). The reinfection rate at 4 months after treatment was 54.5%, 3.6% and 10.3% for Ascaris, Trichuris and hookworm infection, respectively. Within 4 months after treatment almost one-fifth children with Ascaris and hookworm infection reached pre-treatment intensity infection. In Trichuris infection, however more than half of the children reached their pre-treatment intensity infection at 4 months after treatment. Findings suggest that 4-monthly targeted periodic treatment with 400 mg single-dose albendazole in highly endemic areas can have a significant impact on intensity infection of Ascaris and hookworm, but not on Trichuris infection.

Prevalence and some risk factors of Giardia duodenalis infection in a rural community in Malaysia.

A study on prevalence and risk factors of Giardia duodenalis infection was conducted in rural communities of Malaysia. A total of 917 individuals between 2-70 years old (431 males and 486 females), participated in this study. The overall prevalence of G. duodenalis infection was 19.2%. The prevalence was significantly different between different age groups, but not genders. Our study indicated that age < or = 12 years old and the presence of family members infected with G. duodenalis were the risk factors of infection. Person-to-person contact within the family members was the possible mode of transmission. Health education on personal hygiene, together with the treatment of the infected people, may help in reducing and controlling this infection in these communities.

The prevalence of Trichuris, Ascaris and hookworm infection in Orang Asli children.

A community study on the age and sex related prevalence, intensity infection and frequency distribution of Ascaris, Trichuris and hookworm was carried out in 205 Orang Asli (Aborigines) children (95 boys, 110 girls) aged 1-13 years. The overall prevalence of Ascaris, Trichuris and hookworm was 62.9%, 91.7% and 28.8%, respectively. Almost two-thirds of the children were infected with moderate and severe intensity infection of Trichuris, 46.3% had moderate to severe intensity infection of Ascaris. However only 1.5% had moderate intensity of hookworm infection. The prevalence and mean intensity infection (measured by eggs per g) of Ascaris was age-dependent; lower in age group 1-4 years reached peak and stable at age group 5 years and above. The prevalence of Trichuris was high in all age groups and it fluctuated with age; the mean intensity of infection of Trichuris (measured by eggs per g) was age-dependent. Hookworm infection also rose with age and reached peak at 5-6 years, following that the prevalence declined. The frequency distributions of Ascaris, and hookworm were overdispersed. A strong positive correlation (p < 0.001) were observed between Ascaris and Trichuris and between hookworm and Trichuris. A positive correlation (p < 0.01) were also observed between Ascaris and hookworm.

Enterobius vermicularis infection among children aged 1-8 years in a rural area in Malaysia.

The infection rate and relationship of enterobiasis with socio-economic status were determined in children aged 1-8 years, living in a rural area in Malaysia. Of the 178 subjects 40.4% were infected with Enterobius vermicularis. The distribution of enterobiasis among these children were analyzed in relation to age groups and sex. The rate of infection was significantly higher in older children (5-7 years). The association of enterobiasis with other factors studied such as number of persons per house, household income per months and mother's employment status were not significant. The sensitivity of three successive days anal swabs compared to a single swab was found to be statistically significant.

Prevalence of Enterobius vermicularis amongst adults living in hostels by six successive day examination.

The prevalence of Enterobius vermicularis in four groups of adults, all trainee public health inspectors or public health nurses, aged 18-35 years and all living in hostels on campus was studied. The modified scotch tape technique was used and the subjects were taught to do the examination on themselves to detect the presence of eggs over a period of 6 successive mornings. Each was given an elaborately illustrated diagram on how and when to take the samples and given demonstration in groups. The samples were examined by trained people. Most of the subjects took samples on 6 consecutive days. Of the 119 subjects who returned samples, the overall prevalence of E. vermicularis was 9.2% and this was thought to be high for this particular age group. This was due to the higher prevalence (19.4%) in one group, whereas in the others the range was 3.5-8.0%. Based on the samples returned on the first day none of the subjects were detected as having the infection. After examination on 3 successive days (109 subjects) 10.1% were found to be infected (chi 2 = 10.704; d. f. = 1) and after examination on 6 successive days (72 subjects) 13.9% were found to be infected (chi 2 = 3.026; d. f. = 1). There was no significance between examination over 3 successive days and 6 consecutive days (chi 2 = 0.296; d. f. = 1). There was no difference in the prevalence between males and females.(ABSTRACT TRUNCATED AT 250 WORDS)

Some risk factors of Ascaris and Trichuris infection in Malaysian aborigine (Orang Asli) children.

A study on risk factors of soil-transmitted helminths was conducted in a highly endemic area. In all 205 children (95 boys and 110 girls) participated in this study. The overall prevalences of Ascaris, Trichuris and hookworm infection were 62.5%, 91.7% and 28.8% respectively. Only 22.4% of the children had a single infection either by Ascaris or Trichuris; 69.3% had mixed infection and the most prevalent of mixed infection was a combination of Ascaris and Trichuris. Logistic regression analysis confirmed that low level mother's education was a risk factor for moderate and severe infection of Ascaris and age < or = 6-year-old was a protective factor. In Trichuris infection logistic regression analysis confirmed that usage of well-water and age < or = 6-year-old were the risk factors. Logistic regression analysis on worm scores confirmed that usage of well-water and non-usage of toilets were the risk factors from getting severe worm scores and age < or = 6-year-old was a protective factor. Our finding suggest that socio-behavioural (related to mother's education), demographic (children age) and environmental-factors (usage of well-water and non-usage of toilets) are the elements to be considered in the design of long term soil-transmitted helminths (STH) control in an endemic areas.

Efficacy of albendazole in the treatment of Trichuris trichuria and Giardia intestinalis infection in rural Malay communities.

A community study was carried out to evaluate the efficacy of a 3-day course of 400 mg albendazole daily in the treatment of Trichuris trichiura and Giardia intestinalis infection. This treatment regimen was effective in the treatment of Trichuris trichiura and Giardia intestinalis infection with cure rates of 91.5% and 96.6% respectively. Uses of a 3-day course of 400 mg albendazole daily should be considered in mass or targeted soil-transmitted helminths chemotherapy particularly in areas where the prevalence of Trichuris trichiura is high and polyparasitism is common.

Intestinal parasitic infections in man: a review.

Intestinal parasites of importance to man are Enterobius vermicularis, the soil-transmitted helminthes (STH)--Ascaris lumbricoides Tricburis trichiura, bookworms (Necator americans/Ancylostoma duodenale) and Strongyloides stercoralis and the protozoa Entamoeba histolytica and Giardia duodenalis. Other protozoa such as Cryptosporidium sp. and Isopora sp. are becoming important in causing prolonged diarrhea in immunocompromised patients. It is estimated that almost 1 billion, 500 million and 900 million people worldwide are infected by the major nematode species--A. lumbricoides, T. trichiura and hookworms respectively. Most of the infections are endemic and widely distributed throughout poor and socio-economically deprived communities in the tropics and subtropics. Environmental, socio-economic, demographic and health-related behavior is known to influence the transmission and distribution of these infections. In giardiasis, one study indicates that age < or = 12 years and the presence of family members infected with Giardia were risk factors for infection. Most of the infections occur in children and both genders are equally affected. Epidemiological studies of STH infections have shown that the prevalence and intensity of infection are highest among children 4-15 years of age. The frequency of distribution of STH infections is over-dispersed and highly aggregated. areas reinfection can occur as early as 2 months post-treatment, and by 4 months, almost half of the population treated become reinfected. By 6 months the intensity of infection was similar to pretreatment level.

Hookworm infection and reinfection following treatment among Orang Asli children.

In hookworm endemic areas where sanitation is often wanting, reinfection of treated children is a problem. This study was conducted to enumerate the prevalence and the reinfection rate of hookworm in 193 Orang Asli children following treatment with stat dose of 400mg of albendazole at 2 and 4 months post-treatment. All samples were examined using the Kato-Katz and Harada Mori techniques. The overall initial prevalence was 31.0%, with 27.0% in males and 34.0% in females although there was no statistical difference. Only 7.0% of the children had moderate intensity of infection. The overall infection rate at 2 and 4 months post-treatment was 11.0% and 8.0%. New cases were detected at 1.0% and 5.0% at 2 and 4 months post-treatment period. Reinfection rate 2 months post-treatment was 24.0%, and it was 30.0%, 4 months after treatment. All infection at 2 and 4 months post-treatment were light. Long-term strategies incorporating health education on personal hygiene, provision of toilets and safe water supply need to be adopted in these Orang Asli villages to control rapid reinfection.

Nutrient intake and socio-economic status among children attending a health exhibition in Malaysian rural villages.

A dietary survey was carried out in 216 children (109 males, 107 females) aged 1-7 years, living in rural villages in Selangor, Malaysia to assess their nutrient intake and to determine the association between nutrient consumption and socio-economic background. All the children studied had inadequate intakes of energy, iron and niacin according to Recommended Daily Intake (RDI). Children aged of 4-9 years showed inadequate intake of calcium, thiamine and riboflavin. However, the intake of protein, vitamin A and ascorbic acid were above the recommended value. The mean percentage requirements of protein, iron and niacin were significantly higher in children from small families compared with children from large families. However the employment status of mothers had a significantly effect on the mean percentage requirements of niacin. The results indicate that education level of the mothers, is strongly associated with the mean percentage nutrient requirements of children and we strongly feel that this is a strategy to be adopted for improvement in nutrition of children.

PIP: During January-June 1993, in the rural villages of Mukim Labu and Dengkil, Malaysia, a dietary survey was conducted of 216 children 1-7 years old attending a health and worm infestation exhibit. It aimed to determine the dietary intake of these children and to examine the association between dietary intake with age, household income, family size, employment status of mothers, and level of mothers' education. All the children had lower intakes of energy, iron, and niacin than the recommended daily intake (RDI). Their intake of protein, vitamin A, and ascorbic acid tended to be more than the RDI, however. Children 4-9 years old consumed insufficient amounts of calcium, thiamin, and riboflavin. The researchers controlled for age in the remaining analyses, since it is a confounding factor. Children from low-income households had significantly lower intakes of protein, iron, and niacin than those from higher income households (p 0.05). Children from small size families (1-5) consumed more riboflavin than those from larger size families (=or 6) (104.6 vs. 67.4-74.3 mg; p 0.05). Children of working mothers consumed more niacin than those whose mothers were housewives (66.3 vs. 44.1 mg; p 0.05). Mother's education had a positive association with intake of protein, iron, vitamin A, and niacin (p 0.05). These findings suggest that household income, mother's education, and small family size had a positive association with nutrient intake.

Clinical features of malaria in Orang Asli population in Pos Piah, Malaysia.

A malaria survey was conducted to examine the presence of common clinical features of malaria in individuals living in an endemic area of malaria. The overall infection rate was 11.0% with 7.5% and 3.5% infected with Plasmodium vivax and Plasmodium falciparum respectively. The mean parasitaemia level of both species was 2905.9 parasites/microliter blood, with the mean parasitaemia level of P. vivax and P. falciparum at 682.7 parasites/microliter blood and 6981.7 parasites/microliter blood respectively. The infection rates were higher in the younger age group. Hepatomegaly, hepatosplenomegaly and clinical anaemia were significantly associated with malaria. None of the patients were febrile. In conclusion, in low endemic areas, the presence of clinical anaemia, hepatomegaly and hepatosplenomegaly in afebrile individuals could be considered as useful criteria for the presence of asymptomatic parasitaemia. It is important to carry out laboratory diagnostic investigations, to ensure all the asymptomatic parasitaemia which act as reservoirs are detected and treated.

Epidemiological screening of lymphatic filariasis among immigrants using dipstick colloidal dye immunoassay.

We have recently reported that a dipstick colloidal dye immunoassay (DIA) that detect parasite antigens in human serum is sensitive and specific for the diagnosis of active infection of lymphatic filariasis. Rabbit polyclonal antibodies (RbBmCAg) labelled with a commercial dye, palanil navy blue was used to detect filarial antigenemia among Indonesian and Bangladeshi immigrant workers (N= 630) at oil palm estates at Hulu Trengganu District, Peninsular Malaysia. Microfilaremia with Brugia malayi were detected in 51 (8.10 %) individuals, of which 42 (6.67 %) were among the Indonesians and 9 (1.98 %) among the Bangladeshis. Microfilaremia with Wuchereria bancrofti were detected in 33 (5.24 %) individuals of which 15 (2.38 %) were among the Indonesians and 18 (2.86 %) among the Bangladeshis workers. The DIA detected 96 (15.24 %) antigenemic cases which comprise of all the microfilaremic cases and 15 (2.38 %) amicrofilaremic cases. The amicrofilaremic cases with filarial antigenemia consisted of 9 (1. 43 %) Indonesians and 6 (0.95%) Bangladeshis. We have used 6 ul of the RbBmCAg and diluted (1:10) patients' sera per dipstick which make the DIA reagent conservative. The DIA is a rapid test and can be read in approximate 2 hours.. Additionally, coloured dots developed in the DIA can be qualitatively assessed visually for intensity. The DIA does not require sophisticated equipment or radioactivity, and therefore suitable for field application.

A preliminary study on the prevalence of intestinal microsporidiosis in patients with and without gastrointestinal symptoms in Malaysia.

An observational study was carried out to establish the existence of intestinal microsporidiosis among patients with and without gastrointestinal symptoms in Hospital Universiti Kebangsaan Malaysia, Malaysia. A total of 893 faecal specimens from hospitalized patients were examined for microsporidia using a modification of the usual Gram-chromotrope stain technique. One hundred and sixteen (13.0%) patients were positive for microsporidia: 84 (72.4%), 27 (23.3%) and 5 (4.3%) were low, moderate and high excreters of microsporidia spores, respectively. Of the 91 patients with available medical records, microsporidiosis was commonly observed in children aged 0-6 years (26.4%) and adults aged >or=31 years (57.2%). About one-third of this infection was observed in immunocompetent individuals. Among the immunosuppressive group, microsporidia were observed to be more prevalent in patients with haematological malignancy or a combination of malignancy and diabetes mellitus. About 74% of the patients who had microsporidia in their faeces had gastrointestinal symptoms, which could be related to infections or induced by immunosuppressive therapy. The role of microsporidia in causing gastrointestinal symptoms in this population is as yet unclear.

Serum iron status in Orang Asli children living in endemic areas of soil-transmitted helminths.

We conducted a cross sectional study to examine the association of intestinal parasitic infections and protein energy malnutrition (PEM) with iron-status indicators and anaemia among Orang Asli children in Selangor, Malaysia. A total of 281 children aged 2 - 15 years were studied. The data were collected using structured questionnaires, anthropometric measurements and laboratory analysis for blood and faecal samples. All children were infected either by A. lumbricoides, T. trichiura or hookworm and almost 19%, 26% and 3% of the children had severe infection of ascariasis, trichuriasis and hookworm infection respectively. The prevalence of giardiasis among them was 24.9%. Overall, 41.5% of the children were anaemic (haemoglobin < 11.0 g/dL). Of these 61.0% of the children had iron deficiency and 36.5% had iron deficiency anaemia (IDA), which accounted for 88.0% of anaemia in this population. Severe trichuriasis had the most significant correlation with anaemia and iron deficiency in this population. It contributed to low concentrations of haemoglobin, serum iron and serum ferritin and high total iron binding capacity (TIBC). Significant underweight and stunting were associated with low concentrations of haemoglobin and serum iron while significant wasting was significantly associated with low concentration of serum ferritin. Logistic regression analysis confirmed that severe trichuriasis was a strong predictor of IDA. It also confirmed that children who were significantly underweight and whose mother was working were independent predictors of IDA in this population.