The present study was conducted to determine the prevalence of helminth eggs excreted in the faeces of stray cats, dogs and in soil samples. A total of 505 fresh samples of faeces (from 227 dogs and 152 cats) and soil were collected. The egg stage was detected via microscopy after the application of formalin-ether concentration technique. Genomic DNA was extracted from the samples containing hookworm eggs and used for further identification to the species level using real-time polymerase chain reaction coupled with high resolution melting analysis. Microscopic observation showed that the overall prevalence of helminth eggs among stray cats and dogs was 75.7% (95% CI = 71.2%-79.9%), in which 87.7% of dogs and 57.9% of cats were infected with at least one parasite genus. Five genera of heliminth eggs were detected in the faecal samples, including hookworms (46.4%), Toxocara (11.1%), Trichuris (8.4%), Spirometra (7.4%) and Ascaris (2.4%). The prevalence of helminth infections among stray dogs was significantly higher than that among stray cats (p < 0.001). Only three genera of helminths were detected in soil samples with the prevalence of 23% (95% CI = 15.1%-31%), consisting of hookworms (16.6%), Ascaris (4%) and Toxocara (2.4%). The molecular identification of hookworm species revealed that Ancylostoma ceylanicum was dominant in both faecal and soil samples. The dog hookworm, Ancylostoma caninum, was also detected among cats, which is the first such occurrence reported in Malaysia till date. This finding indicated that there was a cross-infection of A. caninum between stray cats and dogs because of their coexistent within human communities. Taken together, these data suggest the potential role of stray cats and dogs as being the main sources of environmental contamination as well as for human infections.
Hookworm-related cutaneous larva migrans (CLM) is characterized clinically by erythematous and slightly raised tracks, located especially on the feet. These tracks may be single or multiple, linear or serpiginous, more or less ramified and intertwined. The length is variable (up to many cm); the width ranges from 1 mm to 4 mm. Tracks are often accompanied by severe pruritus.
In Soil-Transmitted Helminth (STH) control programs, microscopic examination is applied as a standard method for detecting the presence and the number of STH eggs. The time limitations of fresh specimen processing, especially for an accurate quantitative diagnosis, cause the specimen processing to be delayed or should be performed at a referral laboratory. This deferment requires preservatives to keep the stool integrity without reducing the accuracy. The aims of this study were: 1) to compare the proportion of positive samples and the intensity of A. lumbricoides, T. trichiura, and hookworm infection based on the examination of fresh samples and stool preserved by 10% formalin for >12 months and 2) to determine the most reliably accurate between Kato-Katz and mini-FLOTAC methods in detecting A. lumbricoides, T. trichiura, and hookworm eggs in preserved stools both qualitatively and quantitatively. Seventy-eight (78) stool samples were examined by mini-FLOTAC, and KatoKatz methods. Proportion of positive samples of A. lumbricoides, T. trichiura, and hookworms in fresh and in >=12 months 10% formalin preserved stools had no significant difference. Helminths density (eggs per gram of stool/EPG) in fresh samples was fewer compared to EPG in preserved samples (p <0.05) which leads to a lower proportion of moderate and high level groups in fresh stools samples compared to those in preserved samples (p <0.05). In preserved samples, as qualitative method, mini-FLOTAC detected more A. lumbricoides and T. trichiura eggs than Kato-Katz, while hookworm eggs were detected more by Kato-Katz than the miniFLOTAC. As a quantitative detection, Kato-Katz showed higher calculation of STH EPG than mini-FLOTAC. Using 10% formalin preservation for stool samples, the STH eggs' morphology could still be well identified. Homogenization process and low number of samples tested, were acknowledged as the limitation of this study.
This study investigated the distribution of parasites as main contaminants in water environments of peninsular Malaysia (October 2011-December 2011) and the southeastern coast of Thailand (June 2012). Sixty-four water samples, 33 from Malaysia and 31 from Thailand, of various water types were examined according to U.S. Environmental Protection Agency guidelines. Drinking or household water types from both countries were free from parasitic contamination. The recreational/environmental (except a swimming pool in Malaysia) and effluent water types from these two countries were contaminated with waterborne parasites: Giardia (0.04-4 cysts/L), Cryptosporidium (0.06-2.33 oocysts/L), hookworm (6.67-350 ova/L), Ascaris (0.33-33.33 ova/L), and Schistosoma (9.25-13.33 ova/L). The most contaminated sites were recreational lake garden 3 in Malaysia and river 2 in Thailand. Higher concentrations of Giardia, Cryptosporidium, and hookworm were found in samples from Malaysia than in samples from Thailand. The presence of Giardia cysts showed a significant association with the presence of Cryptosporidium oocysts (P < 0.005).
Soil-transmitted helminth (STH) infections of humans fall within the World Health Organization's (WHO) grouping termed the neglected tropical diseases (NTDs). It is estimated that they affect approximately 1.4 billion people worldwide. A significant proportion of these infections are in the population of Southeast Asia. This review analyses published data on STH prevalence and intensity in Southeast Asia over the time period of 1900 to the present to describe age related patterns in these epidemiological measures. This is with a focus on the four major parasite species affecting humans; namely Ascaris lumbricoides, Trichuris trichiura and the hookworms; Necator americanus and Ancylostoma duodenale. Data were also collected on the diagnostic methods used in the published surveys and how the studies were designed to facilitate comparative analyses of recorded patterns and changes therein over time. PubMed, Google Scholar, EMBASE, ISI Web of Science, Cochrane Database of Systematic Reviews and the Global Atlas of Helminth Infections search engines were used to identify studies on STH in Southeast Asia with the search based on the major key words, and variants on, "soil-transmitted helminth" "Ascaris" "Trichuris" "hookworm" and the country name. A total of 280 studies satisfied the inclusion criteria from 11 Southeast Asian countries; Brunei, Cambodia, Indonesia, Lao People's Democratic Republic (Lao PDR), Malaysia, Myanmar, Philippines, Singapore, Thailand, Timor-Leste and Vietnam. It was concluded that the epidemiological patterns of STH infection by age and species mix in Southeast Asia are similar to those reported in other parts of the world. In the published studies there were a large number of different diagnostic methods used with differing sensitivities and specificities, which makes comparison of the results both within and between countries difficult. There is a clear requirement to standardise the methods of both STH diagnosis in faecal material and how the intensity of infection is recorded and reported in future STH research and in monitoring and evaluation (M&E) of the impact of continuing and expanding mass drug administration (MDA) programmes.
The intestinal parasites of schoolchildren from an urban and a rural area on Penang island, Malaysia were compared. Examination of stool samples for helminth eggs showed that helminths found were Trichuris, Ascaris and hookworms. The results indicate that there is no significant difference (p<0.05) between rural and urban schoolchildren as regards to the prevalence of the three species of helminths. An extensive control program targetted at schoolchildren to monitor the helminth problem on the island is suggested.
Currently, information on prevalence of soil-transmitted helminth (STH) infections among different tribes of Orang Asli (aboriginal) is scarce in Malaysia. The present study is a cross-sectional study aimed at determining the factors associated with the prevalence of STH infections among the Proto-Malay, Negrito and Senoi tribes. Faecal samples were collected from 500 participants and socioeconomic data was collected via pre-tested questionnaire. All samples were processed using formalin-ether sedimentation and Wheatley's trichrome staining. Trichuris trichiura (57%) was the most common STH seen among the participants, followed by Ascaris lumbricoides (23.8%) and hookworm (7.4%). Trichuriasis and ascariasis showed an age-dependency relationship; significantly higher rates were observed among Senois who aged <15 years. Likewise, Negritos also showed an age-dependency association with ascariasis affecting mainly the under 15 years old individuals. Multivariate logistic regression model indicated the following predictors of trichuriasis among these communities; being aged <15 years, consuming raw vegetables, belonging to a large household members (≥8) and earning low household income (
Geohelminthiasis is a worldwide problem, especially in low-income countries. Children from rural areas and those living in poverty, lacking basic health amenities and having poor environmental sanitation are likely to be affected. Adverse effects such as anemia, protein malnutrition, colitis are common which can affect both the children's physical and mental growing development. A cross-sectional study on geohelminthiasis was conducted among children from 238 households in 13 villages in Kota Marudu of northern Sabah, East Malaysia. The study involved interviewing villagers using questionnaires to collect demographic and socio-economic data, getting faecal samples from the children, collecting soil samples and identifying parasite eggs with microscopy and molecular methods. A total of 407 children (6 months-17 years old) enrolled in the study. Geohelminthiasis was detected in the faecal samples of children from 54% (7/13) of the villages with mean prevalence of infection per village of 9.0% (0%-34.9%). On a household basis, 18% (43/238) of the households sampled had infected children, with mean prevalence rate per household of 11% (0%-43%). The prevalence was for Ascaris lumbricoides: 9.6% (39/407), Trichuris trichiura: 2.7% (11/407) and hookworms (Necator americanus and Ancylostoma sp.): 2.7% (11/407). The overall mean infection rate of the children examined was 14.3%. Significantly higher prevalence was recorded for the children of mothers who did not have any formal education (p = 0.003); household income of less than USD119 (RM500) (p<0.001); children from homes without proper sanitation facilities (p<0.001); children who usually go about barefoot (p<0.001) and not washing feet before entering the house (p = 0.017). Soil samples were found to have geohelminth eggs or larvae which could be due to unhygienic sanitation practices. This study shows the geohelminthiasis is prevalent in the villages, and the risk factors are lack of maternal education, low income, poor sanitation facilities and irregular deworming practice. Expanding deworming coverage in the study region may help reduce the worm infections in these communities, so that the mental and physical development of the children would not be affected by geohelminthiasis. The data on the prevalence of geohelminthiasis in this study would contribute to better public health monitoring and operation to reduce the infection in rural areas.