The recovery of six adult Gnathostoma spinigerum Owen, 1936 from a civet cat, Prionodon linsang Hardwick, constitutes the second reported record of this parasite and the first authenticated case of adult worms found in a wild animal from Malaysia. The food habits of the infected P. linsang as an important link in the transmission of G. spinigerum in the intermediate and definitive hosts together with the probable distribution of this parasite are discussed.
The prevalence and intensity of intestinal nematode infections were assessed during 3 anthelminthic interventions in an urban community in Malaysia. The prevalence levels of Ascaris lumbricoides at Interventions 1, 2 and 3 were 30.6%, 18.9% and 15.5%, respectively and the mean intensities were 1.9, 0.75 and 0.81 worms per person. For Trichuris trichiura, the prevalence levels at Interventions 1, 2 and 3 were 46.9%, 21.6% and 15.7%, respectively. The mean intensities for T. trichiura at Interventions 1, 2 and 3 were 3.30, 0.92 and 0.07 worms per person. No gender-related prevalence and intensity were observed for the two geohelminths in this community. Prevalences and intensity had convex age profiles. Although repeated chemotherapeutic intervention reduced both prevalence and intensity levels, intensity was a more sensitive indicator than prevalence. The results indicate that age-targetting treatment at school children of 7-12 years of age would be an appropriate strategy for this community.
Studies have shown that smokers rationalize smoking by self-exempting beliefs. This study explored lay beliefs about smoking in Kelantan, Malaysia, using focus groups among outpatients, medical students and staff, and a questionnaire survey of 193 male smokers. In focus groups, patients said they could do something to make smoking safe. When asked, 'Do you think there are any safe ways to smoke?' 132/193 (68%) male smokers described at least one way. The commonest were 'drink water' (69/193, 36%), 'use a filter' (60/193, 31%), 'smoke after food' (27/193, 14%), and 'take sour fruit' (21/193, 11%). At three- or six-month follow-up, numbers agreeing with these beliefs were: for 'drink water' 67/115 (58%), for 'take sour fruit' 61/115 (53%), and for 'smoke after food' 38/115 (33%), with 88/115 (77%) supporting at least one. The main explanations for water were that it cleaned or moistened the lungs or throat. Sour fruit was described as cleaning, and sometimes as 'sharp', able to scrape out the essence of cigarettes. The conclusion is that self-exempting false beliefs about smoking are widespread, and here they probably represent an extension of the traditional humoral system. Anti-smoking campaigns and health workers in smoking cessation services should address these beliefs.
Study site: outpatients clinic (Klinik Perubatan Masyarakat, KPM), Hospital Universiti Sains Malaysia (HUSM), Kelantan, Malaysia
Smoking deception is often ignored, but is important in health care. In this trial it was assessed at both study entry and outcome. At study entry, 1,044 males at a primary care clinic were asked smoking status and tested for breath carbon monoxide (CO). Of self-reported non-smokers, 57/402 (14%) were actually smokers, as were 59/251 (24%) of self-reported ex-smokers. The self-reported smokers (n=387) entered a randomized, controlled trial where the intervention comprised four questions on knowledge and beliefs about smoking, standardized verbal advice against smoking, and a leaflet. At follow-up, subjects were also questioned about beliefs. Follow-up was difficult, but 191/387 (49%) attended at three or six months. Of 27 who claimed to have quit, 6 (22%) were deceivers and 21 were confirmed quitters. Cessation did not differ between intervention and control groups. Overall confirmed cessation at six months was 16/387 (4.1 %). Confirmed quitters were significantly lighter smokers than deceivers and still smokers. There were non-significant trends between the outcome groups whereby deceivers had least knowledge and most lay beliefs, and quitters had most knowledge and fewest lay beliefs. The lay beliefs may prevent some smokers from quitting.
Study site: open-access outpatients
clinic (KPM) attached to the teaching hospital
(HUSM) of Universiti Sains Malaysia
No focalization of rats (Rattus tiomanicus and R. argentiventer) infected with Rickettsia tsutsugamushi could be discerned over a 500 m trapping transect at the border between a forest and lalang grass (Imperata cylindrica). R. tiomanicus appeared to occupy 250 m of the transect on the average and had periods during which infections were observed which averaged 97 days. Calulations indicated that more than 50% of individuals become infected over their life-time. The high rate of infection in this and other areas described in earlier publications and the habits of the rats suggest that infected mites are densely and widely dispersed in the areas studied in Malaysia.
Successful colonization of Mansonia dives, the principal vector of subperiodic Brugia malayi was established in a field insectary. Mean egg clusters laid on Eichhornia crassipes, Pistia stratiotes, Homalomena cordata and polystyrofoam strips were 12.0, 10.4, 9.5 and 13.7 respectively. However, the mean number of first instar larvae hatched from each egg cluster laid by females on the three plant substrates (range 51.1 to 58.6) was higher than that laid on the polystyrofoam strips (41.8). There were no significant differences in the success pupation and adult emergence rates among the three host plants used as attachment substrates. Adult emergence occurred at a mean of 10.8 days. The first adult emergence was observed at the 25th day after hatching and continued till the 50th day. The 50% mortality rates for the adults were estimated as 8 days for the males and 14 days for the females. The mean gonotrophic cycle ranged from 3.8 to 4.3 days with a mean of 4.04 days. 63.6% of Ma. dives females oviposited in a medium of rat dung and water. The mean incubation period of eggs ranged from 5.2 to 6.5 days with a mean of 5.7 days. The biology of Ma. dives and Ma. bonneae is briefly compared.
The measurement of the ultimate effects of the microbial insecticides on mosquito density is best obtained by assessment of adult populations. The main aims of this study are: (1) to assess the effect of Bacillus thuringiensis israelensis (Bti) FC Skeetal and Bactimos briquettes on the emergence rate of Mansonia bonneae developed from the introduced first-instar stage larvae and (2) to measure the effect of these two formulations of insecticides on Mansonia adult populations emerging from the natural breeding plots. Bti Skeetal and Bactimos briquettes at the lower applied dosages of 2.3 kg/ha and 1 briquette case/20 m2 respectively achieved 39-40% pupation rates and 31.5-34.2% adult emergence rates. At these low applied dosages, there was little or no direct effect on pupation from the surviving larvae and thereafter on the emergence of adults from the pupae. A two-fold increase in dosage, however, produced a drastic decline in the pupation rate and adult emergence rate. The rates dropped to 6.5% (pupation) and 4.3% (adult emergence) of the total larvae for Bactimos briquettes and to merely 1.5% (pupation) and 1.3% (adult emergence) of the total larvae for Skeetal. In studying the effect of Bti on the field populations of Mansonia mosquitos, two plots each were treated with Bactimos at 1 briquette case/10 m2 and Skeetal at 4.6 kg/ha. A wooden pyramid-shaped screened cage was placed on a cluster of host plants for a period of 2 weeks to trap the emerging adult mosquitoes. There were a total of 24 clusters of host plants in each plot.(ABSTRACT TRUNCATED AT 250 WORDS)
To study the distribution of presenting features and their prognostic significance in neuroblastoma treated in a single institution in Malaysia. A retrospective study was made of 78 neuroblastoma cases diagnosed and treated in the University Hospital, Kuala Lumpur, Malaysia between June 1982 and February 1997. Diagnosis was established by standard histological criteria. The presenting features were evaluated for their distribution and prognostic influence. Disease-free survival from diagnosis was the outcome variable of interest. The ages ranged from 0.1 to 11 years old (median: 3 years old). The tumor originated from the adrenal glands in 83% and the majority of cases presented in advanced stage (stage III 22%, stage IV 66%). Bone marrow was the commonest site of distant metastasis occurring in 45% of patients. The main presenting signs and symptoms in decreasing order were pallor, fever, abdominal mass, weight loss, and bone/joint pain. Univariate analysis conferred age, initial stage and Hb level as significant prognostic factors. No influence in disease-free survival was found for sex, race, primary site, urinary vanillylmandelic acid level, white cell count and platelet count. Overall 2-year disease-free survival was achieved in 27 (39%) patients. Four patients underwent bone marrow transplant, three of whom achieved 2-year disease-free survival. The results suggest that age, initial stage and hemoglobin level are significant prognostic factors based on univariate analysis. In addition, more Malaysian children presented with adrenal primary site and advanced disease compared to previous reported studies.
The nutritional status of 896 Kadazan children below 6 years of age from 23 villages of Tambunan District were studied. When stunting and wasting were defined as those who were below two standard deviations of height-for-age and weight-for-height (Waterlow et al, 1977) and based on the National Center for Health Statistics reference population, 67.6% of boys and 66.8% of girls were stunted while 12.3% of boys and 8.3% of girls were wasted. Weaning foods and toddler feeding practices were unsatisfactory. The role of health education on child care and feeding practices is emphasized.
A survey was conducted to document the blood pressures of two indigenous groups (Kadazans and Bajaus) who reside in rural Sabah in East Malaysia. Their health knowledge status is also recorded. Fifty percent of those surveyed were unable to associate high blood pressure with a risk factor and as high as 38% were unaware of the consequences of high blood pressure. A total of 16.2% had blood pressures > or = 140/or 90mm Hg while 3.9% had blood pressures > or = 160/or 95mm Hg. While these figures are low compared to those of developed countries, lifestyle changes associated with rapid urbanization in Malaysia may be expected to increase hypertension prevalence. The strengthening of health education programs is timely as health knowledge is limited and many hypertensives default treatment.
Discrepancies in angiotensin-1 converting enzyme (ACE) allele genetic susceptibility with disease etiology have been attributed to ethnic differences. We investigated ACE gene polymorphism of the multiethnic Malaysian population by utilizing nested polymerase chain reaction. Allelic frequency of 0.65 and 0.35 for I and D allele, respectively in the pooled population was comparable with other Asian populations. A significant association was found between the Malaysian ethnic groups and ACE I/D genotype. The II genotype was found at higher frequency among the Malays but a greater frequency of DD genotype among Indians.
CDC Light traps were used to study the attractant effect of CO2 and 1-octen-3-ol on trap catches of mosquito populations at three different locations in Malaysia. There was a significant increase in the number of mosquitos caught in traps baited with CO2 and CO2 with 1-octen-3-ol. The number of mosquitos caught in the CDC light trap and in the CDC light trap baited with 1-octen-3-ol alone were very few. 1-octen-3-ol and CO2 acted synergistically in attracting significantly greater numbers of Culex tritaeniorhynchus. However Anopheles sp. were not very attracted to light traps even with attractants added to them.
Field tests were conducted to compare the degree of protection from bites of Mansonia species and Anopheles maculatus by applying two repellent/insecticidal bars, MOSBAR and MOSKIL, to exposed arms and legs. Human test subjects were exposed to natural populations of mosquitos for an 8-hour night time period while using the repellent/insecticidal bars. MOSBAR gave good protection against the bites of Mansonia and An. maculatus. MOSKIL was effective against An. maculatus but not against Mansonia. High mortality was observed among the mosquitos collected from human test subjects treated with the repellent/insecticidal bars. Use of MOSBAR in terms of cost-effectiveness and safety by field and health workers entering into malaria and filariasis endemic areas is discussed.
Industrial development in Malaysia is discussed in relation to impact on health. Trends in Malaysia are evaluated and the findings of some studies in Malaysia are reviewed.
Non-haemoglobin liver iron was estimated in 275 presumably normal individuals from Kuala Lumpur and Singapore at necropsy. Liver Iron concentrations were highest during the first two years after birth but declined sharply during childhood. They then rose gradually and reached a value of 20 mg/100gm in adult males. Liver iron concentrations of childbearing women remained low and it was only after menopause that values in women rose to those of males. Liver iron stores increased with age to a plateau of about 300 mg in adults, suggesting that this value may represent the adult size for liver iron store. Among the three major ethnic groups in Malaysia and Singapore, Chinese, being in a better socio-eonomic class, had larger liver iron stores. The median liver iron concentrations of Malaysians and Singaporeans, on the whole, were lower than those reported from western populations and as many as 35 per cent of the women were in a subclinical state of iron deficiency.
Two separate observations from recent electrophoretic studies of the systematics and population genetics of laboratory-reared populations which had a long history of colonization in various laboratories, were found to be inconsistent with the present study which used wild-caught populations from East Malaysia. Reanalysis of the two data sets generally indicated a low amount of genetic variation in laboratory colonies. The latter is characterized by higher frequency of monomorphic loci, low average heterozygosity values and, in one extreme case, no variability at two loci. However, natural populations of An. balabacensis and An. leucosphyrus showed more protein variability by the use of polyacrylamide gel electrophoresis. Since laboratory-maintained mosquitoes are genetically and phenotypically different from those in the field, results of laboratory studies on the systematics and population genetics of Anopheles species complexes may be biased.