Introduction Globally, the neglected intestinal parasitic infections (IPIs) such as soil-transmitted helminth (STH) and protozoa infections have been recognized as one of the most significant causes of illnesses and diseases especially among disadvantaged communities. With an average prevalence rate of 50% in developed world, and almost 95% in developing countries, it is estimated that IPIs result in 450 million illnesses [1], [2], [3]. These infections are ubiquitous with high prevalence among the poor and socioeconomically deprived communities where overcrowding, poor environmental sanitation, low level of education and lack of access to safe water are prevalent [4], trapping them in a perennial cycle of poverty and destitution [5]. These parasitic diseases contribute to economic instability and social marginalization; and the poor people of under developed nations experience a vicious cycle of under nutrition and repeated infections leading to excess morbidity with children being the worst affected [2], [6]. Of these illnesses, infections by STH have been increasingly recognized as an important public health problem and most prevalent of IPIs [7]. STH infections caused by Ascaris lumbricoides, Trichuris trichiura and hookworm (Necator americanus and Ancylostoma duodenale) are most significant in the bottom billion of the world's poorest people (i.e., RM 500 54668 45627 83.540.0 7.60 (5.30–11.13)1 <0.001 Water supply status*Untreated (river, well, rain water)Treated pipe water 317399 275249 86.862.4 2.84 (2.08–3.86)1 <0.001 Presence of proper latrine systemNoYes 212504 181343 85.468.1 2.19 (1.54–3.10)1 <0.001 Type of toilet facilityNonePour flush toilet 538178 44678 82.943.8 3.29 (2.62–4.12)1 <0.001 Defecation places status*Others (Bush, River)Pour flush toilet 550166 45668 82.941.0 3.45 (2.76–4.32)1 <0.001 Close contact with pets/livestockYesNo 65165 47252 72.580.0 0.73 (0.44–1.20)1 0.193 Garbage disposalIndiscriminatelyCollected 198518 168356 84.868.7 2.06 (1.45–2.94)1 <0.001 Iron supplementNoYes 412304 303221 73.572.7 1.03 (0.81–1.32)1 0.801 Anthelminthic drugNoYes 374342 286238 76.569.6 1.29 (1.01-1.65)1 0.038 N: Number examined; no: Number positive. Reference group marked as OR = 1; CI: Confidence interval. Significant association (p<0.05). * Variables were confirmed by multivariate analysis as significant predictors of IPIs. Discussion As shown by the results of the present study, intestinal parasitic infections (IPIs) are still a major public health problem (i.e., overall prevalence of 73.2%) among the impoverished and underprivileged communities in rural and remote West Malaysia. However, this study also observed some very encouraging trends. In Sungai Layau village where each family was provided with a concrete house and basic amenities like treated water supply, prevalence of IPIs was shown to be significantly lower (4.5%). This proved that proper provision of basic infrastructure and education are effective tools to reduce the prevalence of these infections. On the contrary, in Betau, Kuala Betis, Sungai Bumbun, Sungai Perah, Gurney, Pos Iskandar and Bukit Serok villages where some villagers still lived in traditional-built houses and using water from wells or rivers, prevalence of IPIs were very high. This was evident in the present findings whereby Betau village which was less provided or developed had the highest rate of infection (97.8%). Results also showed that STH infections (73.2%) were more common compared to protozoa infections (20.1%). T. trichiura infection is the most common (66.8%) followed by A. lumbricoides (38.5%) and hookworm (12.8%). These findings were in agreement with other previous local studies where T. trichiura infection was found to be the most prevalent (range: 26.0% to 98.2%), followed by A. lumbricoides infections (range: 19.0% to 67.8%) and lastly hookworm infections (range: 3.0% to 37.0%) [17], [18], [19], [20], [21]. However, global data has indicated that A. lumbricoides infections were the most prevalent among the three STH infections. The higher rate of T. trichiura infection has been reported to be due to the ineffective dosage and choice of anthelminthic used. Currently, the recommended treatment regime for STH infection is broad spectrum anthelminthics such as albendazole and mebendazole. Important therapeutic differences do exist between these drugs which affect their uses in clinical practice [22]. Both drugs are effective against ascariasis in single dose, whereas single doses of either albendazole or mebendazole have been found to be ineffective in many cases of trichuriasis [22]. Furthermore, potential resistance of T. trichiura to anthelminthic drugs has been highlighted in two intervention studies in Malaysian communities [23], [24]. It has been noted that unscheduled deworming without proper monitoring system was common among the children of these communities. Since the mass deworming program of schoolchildren has been discontinued in 1983 [25], some of the children received anthelminthic drug during visits to health clinic or from their school medical health team. Some parents have also bought anthelminthic drug for their children without following the recommended treatment intervals (i.e., periodic deworming) and this could have resulted in the inefficacy of the drug and subsequently lead to drug resistance [24]. Another important problem encountered in treatment is the high rate of re-infection especially in highly endemic areas. Local studies among rural communities have found that re-infection can occur as early as 2 months post treatment, by 4 months almost half of the treated population had been re-infected [24] and by 6 months the intensity of infections had returned to pre-treatment levels [26]. Similar findings have also been reported in other parts of the world indicating that by 6 months, the intensity of infections of T. trichiura and A. lumbricoides were similar to pre-treatment levels [27]. WHO has recommended that mass deworming programme should be carried out in communities when the cumulative STH prevalence is more than 50% or the cumulative percentage of moderately or heavily infected individuals is more than 10% [28]. As the present findings have indicated that the overall prevalence was 73.2%, it is strongly recommended that mass deworming programmes are restored and a systematic evaluation of treatment regime must be put in place to reduce the rates of re-infection. As for protozoa infections, the overall prevalence was 21.4%. However, in contrast with the latest local study in rural area, Noor Azian and colleagues reported very high rates of protozoa infection (72.3%) [29]. The present study found that G. duodenalis (10.4%) was the most predominant protozoa, followed by E. histolytica/dispar (10.2%) and lastly Cryptosporidium sp. (2.1%). In Malaysia, the prevalence of G. duodenalis infections varied from 2.0% to 29.2% while the prevalence of E. histolytica/dispar infections was reported to range from 1.0% to 18.5% among rural community [23], [29]. Although amoebic liver abscess (65% of 34) has been documented in patients admitted to an urban hospital in Malaysia [30], information from rural communities is not available as this infection can only be confirmed in a hospital setup. Two previous studies have indicated that Cryptosporidium sp. infections in rural areas ranged from 5.5% to 20.1% [31], [32]. The present study also reported 2 cases (0.3%) of Fasciolopsis/Fasciola sp. infection in Gurney village. This infection is most probably spurious due to consumption of infected animal liver. To date, there has not been any published data on intestinal fluke infection in West Malaysia, however, a case report of fasciolopsiasis by Fasciolopsis buski has been reported among rural community in East Malaysia [33]. In addition, two reported cases of food-borne diphyllobothriasis after consuming sushi and sashimi have also been reported in urban West Malaysia [34], [35]. Previous local studies indicated that there was a web of risk factors associated with the high prevalence of IPIs which included age, low family income, inadequate sanitation, presence and close contact with livestock or pets, untreated water supply, low level of parental education, poor geographical and personal hygiene [17], [22], [23]. Using multivariate analysis, the present study confirmed that children, low household income, untreated water supply, indiscriminate defecation were significant risk predictors of IPIs. This finding is further confirmed with the significantly lower prevalence in Sungai Layau village where household incomes are much higher and basic amenities provided by the government are fully utilized by the villagers. Conclusion Intestinal parasitic infections are highly prevalent and are major public health concerns among the poor and socioeconomically deprived rural and remote communities in West Malaysia. Given that IPIs are intimately associated with poverty, poor environmental sanitation and lack of clean water supply, it is crucial that these factors are addressed effectively. Improvement of socioeconomic status, sanitation, health education to promote awareness about health and hygiene together with periodic mass deworming are better strategies to control these infections. With effective control measures in place, these communities (especially children) will have a greater opportunity for a better future in terms of health and educational achievement. 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