A study of 1,437 unselected febrile patients in rural Malaysia yielded a diagnosis of leptospirosis in 86 (6.0%). The clinical syndrome was mild to moderate in all cases, jaundice was observed in only 2 (2.3%) and no deaths were documented. The diagnosis was not clinically obvious in most cases, and it is apparent that many infections must be going unnoticed at present.
MeSH terms: Fever/etiology*; Headache/etiology; Humans; Jaundice/etiology; Leptospirosis/complications*; Leptospirosis/diagnosis; Malaysia
A survey of Angiostrongylus malaysiensis among wild rodent and molluscan hosts was made in the Tuaran Central Agricultural Research Station and within the vicinity of Tuaran, Sabah. Three of 19 Rattus rattus diardii, one of 2 R. exulans and one R. argentiventer were found naturally infected with the parasite. In this survey 56 of 382 molluscs comprising of Pila scutata, Achatina fulica and two species of land slugs, Laevicaulis alte and Microparmarion malayanus, were found naturally infected with the parasite. Samples of larvae from each of these molluscs were experimentally transferred to laboratory albino rats and adult worms consistent with A. malaysiensis were recovered. Comparison of the rat hosts and the molluscan intermediate hosts of the parasite in Peninsular Malaysia, Sarawak and Sabah was made, and the finding of A. malaysiensis in Tuaran is the first report of the parasite from Sabah. The distribution of the parasite throughout Malaysia is discussed. Observation on the human consumption of the freshwater snail, P. scutata, was made. Although the infection rate of this snail is low compared with other molluscan hosts examined. The importance of this mollusc as a potential source of human infection should not be overlooked. Hospital records for 1974 and 1975 were examined and clinical human angiostrongyliasis was rarely recorded in Sabah.
A comparative epidemiological and anthropometric survey was conducted among Ibans, the largest indigenous ethnic group in Sarawak, in three regions where the endemicity of goitre exhibited marked differences , to assess the effect of endemic goitre on somatic growth. In the Ai river region the prevalence of goitre was 99.5%; 35% having grade 3 goitres, 55% grade 2 goitres and 9.5% grade 1 goitres. At Rubu the prevalence of endemic goitre was 74%; 3% having grade 3 goitre, 16% grade 2 goitre and 55% grade 1 goitre. In the Bajong region relatively few people were detected with goitre and most of these had migrated from other regions. Neurological cretinism was estimated at 3.6% in the severely goitrous Ai river population but was not detected in the other regions. Anthropometric data obtained from the three adult populations did not reveal any statistically significant differences in the following parameters: weight, height, weight/height ratio, height/sitting height ratios, head circumference, scapular skinfold thickness and left mid arm muscle circumference. The haemoglobin, serum total protein and serum albumin concentrations were similar in the three populations. It is concluded that endemic goitre occurs with a frequency of close to 100% in certain Iban populations which represents one of the highest incidences of endemic goitre in the world. Neurological cretinism is common in this population. Our observations suggest that body proportions and somatic growth do not vary among similar ethnic populations exhibiting greatly different endemicity of goitre. Although no iodine balance studies were performed, assessment of diets suggested that iodine deficiency is a significant contributory factor in the development of endemic goitre in Sarawak. Urgent attention to iodine supplementation is indicated to prevent the development of endemic goitre and neurological cretinism.
The weights and heights of 3,312 Malaysian primary school boys and girls, aged 6 to 11 years, belonging to various ethnic groups in Malaysia were measured. On the whole, the Chinese children were taller and heavier than the Malay and the Indian children who were the least heavy among the three ethnic groups. Economically the Indians were the poorest among the three ethnic groups and they also had the largest family size. When the household incomes were taken into consideration it was found that the growth achievement of the higher income children was better than that of the poorer children, irrespective of their ethnic groups. It is interesting to note that, although the Indian children as a whole, were the least heavy of the three ethnic groups, yet the growth achievement of the higher income Indian children was similar to that of the higher income Chinese children. The differences in growth achievement of the various ethnic groups are probably due to environmental differences, rather than genetic differences. It seems likely that Malaysian children of different ethnic groups (Malay, Chinese and Indian) can attain similar statures if environmental conditions are similar.
MeSH terms: Body Weight; Child; China/ethnology; Ethnic Groups; Female; Growth*; Humans; Income; India/ethnology; Malaysia; Male
The primary objective of this project was to study the life cycle and ecology of Plasmodium pitheci, a malaria parasite of the orang-utan. The field work was based on the orang-utan rehabilitation centre in the Sepilok Forest Reserve of eastern Sabah. Two visits were made to Sepilok, the first in February and March, 1972, and the second (by W.P.) in January 1974. On the first visit two species of "surrogate host" were taken to Sabah, i.e. chimpanzees and Aotus monkeys for experimental work. The arboreal habitat of the orang-utan in the dipterocarp forests of eastern Sabah is described. In the Sepilok Forest Reserve dwell gibbons and leaf-monkeys, in addition to a small population of semi-domesticated and wild, free-ranging orang-utans of various ages. Although numerous species of anopheline mosquitoes have been collected in eastern Sabah, longitudinal studies are not available. Anopheles balabacensis was caught both attracted to orang-utans and to man at Sepilok. This species which is the main vector of human malaria in the north of Borneo, is suspected also of transmitting orang-utan malaria in this part of Sabah. Repeated blood examinations have been made on a number of orang-utans in the centre since 1966 and a high prevalence of infection was recorded with Plasmodium pitheci. In 1966 10 out of 19 animals had demonstrable parasitaemia. Detailed case histories are presented to show the course of parasitaemia in several orang-utans. Infections of P. pitheci were found to run a very chronic course. During the 1972 expedition a second, previously undescribed malaria parasite of the orang-utan was discovered, and was named P. silvaticum. The new parasite was successfully transmitted both by blood inoculation and, later, by sporozoite inoculation, into splenectomized chimpanzees. Although both species of malaria parasite may cause transitory signs of illness, orang-utans in general appear to be little discomforted by the infection. The animals do however suffer from other infectious diseases such as amoebic and balantidial dysentery, and melioidosis is a serious natural hazard which may have accounted for several deaths of wild orang-utans. An unidentified, intraerythrocytic structure that appeared in the blood of one chimpanzee, which had been inoculated with blood from an orang-utan, may have contributed to its death. Detailed descriptions and illustrations of P. pitheci and P. silvaticum are given. All stages of the life cycle of P. silvaticum are known (the tissue stages having been described in the liver of a "surrogate host", the chimpanzee) but only the blood and sporogonic stages of P. pitheci have been seen. This species was not infective to a chimpanzee, although there is an earlier report of a transient infection in this host by other workers. In the blood both parasites showed a tertian periodicity. From the appearance of the tissue schizonts on the seventh day it was estimated that the complete pre-erythrocytic cycle of P. silvaticum in the chimpanzee would occupy 8 days. P...
An immature merocyst of Hepatocystis malayensis and gametocytes of H. brayi were studied with the electron microscope. The merocyst consisted of a highly complex cytoplasmic reticulum ramifying through an amorphous matrix: the entire complex was enclosed by a simple unit membrane. The host cell was apparently destroyed completely during growth of the cyst. Immature gametocytes were highly amoeboid and showed extensive vacuolisation or attenuation of the cytoplasm. The nucleus contained one or two prominent nucleoli. Mature gametocytes had compact cytoplasm and contained pyriform osmiophilic bodies which were believed to function in the release of the parasites from the host cells. Macrogametocytes were distinguished from microgametocytes by cytoplasmic differences in numbers of ribosomes, and cristate mitochondria and in the extent of development of the smooth endoplasmic reticulum. The compact nuclei of the macrogametocytes had inconspicuous DNA but prominent nucleoli whereas those of the microgametocytes were irregular and showed a central aggregate of DNA. In microgametogenesis karyokinesis of the parent nucleus was delayed until axoneme formation was complete. Then the nuclear buds were extruded into emerging microgametes. At fertilisation the plasmalemmas of the two gametes fused and the single axoneme and nucleus of the microgamete moved into the cytoplasm of the macrogamete.
In an attempt to discover how the phenomenon of amok is viewed within its indigenous culture, the authors studied and interviewed 21 subjects in West Malaysia who were labeled as amok. This investigation showed that both the subjects and the Malay culture view amok as psychopathology, that amok cases are disposed of in line with this view, and that the behavior of the amok person conforms to social expectations of the phenomenon. Despite cultural proscriptions, however, the act is purposive and motivated and is subtly sanctioned by Malay society.
MeSH terms: Adult; Aged; Mental Disorders/diagnosis*; Commitment of Mentally Ill; Ethnic Groups*; Hospital Records; Humans; Interview, Psychological; Length of Stay; Malaysia; Male; Middle Aged; Motivation; Psychotic Disorders/complications; Rural Population; Seasons; Social Perception; Stress, Psychological; Time Factors; Violence
The pace of urbanization in Peninsular Malaysia was slower in the most recent intercensal interval, 1957 to 1970, than in the previous period, 1947 to 1957. Most of the small change in the rural-urban balance from 1957 to 1970 appears due to the growth of towns into the urban classification rather than to a redistribution of population into the previous urban settlements. A number of towns in Peninsular Malaysia do show exceptional growth from 1957 to 1970, but there seems to be no clear relationship between a city's size and its subsequent growth. The rural areas on the outskirts of the largest cities do show rapid growth, especially the periphery of the capital city. It appears that neither the classic model of urbanization based upon Western experience nor the over-urbanization thesis explain the urbanization process in Peninsular Malaysia.
MeSH terms: Employment; Humans; Malaysia; Population Growth; Socioeconomic Factors; Urbanization*
Eimeria tenggilingi is described from the pangolin or scaly anteater, Manis javanica, in Malaysia. The spheroid to subspheroid oocysts average 18.9 X 17.8 mum. The oocyst wall is composed of 3 layers, each approximately 0.6 mum thick. The 2 outer layers are striated and yellowish green. The inner layer is dark brown. One or 2 polar granules are present, but an oocyst residuum is absent. Ellipsoid sporocysts average 12.4 X 6.2 mum. A sporocyst residuum is present. This is the first Eimeria species reported from a host in the order Pholidota.
MeSH terms: Animals; Xenarthra/parasitology*; Eimeria/classification*; Eimeria/cytology; Feces/parasitology; Malaysia
Insecticides Abate, DDT, Dowco-214, Dursban, fenitrothion, fenthion, gamma-HCH, and malathion were tested against the field collected fourth instars larvae of Mansonia from Penang Island, Malaysia. The larvae appeared to be highly susceptible to Dursban and Abate with LC50 values of 1.54 and 1.92 parts per billion respectively. Other chemicals, in decreasing degree of effectiveness, were gamma-HCH, fenthion, P,P'-DDT, Dowco-214, fenithrothion and malathion. The potential use of these chemicals in Mansonia control was discussed. A simple method for collecting and testing Mansonia larvae was also described.
Based on the prevalence of antibody, an estimated 3% of the population of rural Malaysia is infected with Rickettsia tsutsugamushi each year, resulting in positive antibody rates in focal areas of 6 to 69%. Most of these infections do not appear to produce clinical scrub typhus. A wide range of seropositivity rates was found in areas otherwise resembling each other in predominant occupation, terrain, and nearby habitat. The prevalence rates however were significantly higher in people who worked in forested areas and significantly lower in people with urban occupations.
This is a review of 261 patients operated for 271 instances of mechanical intestinal obstruction over a 5-year period in a developing country in the tropics. The pattern of intestinal obstruction in Chinese is similar to that in Caucasians, where adhesions account for the largest number of cases. The occurrence in Malays, Indians, Pakistanis and Ceylonese is similar to that in other developing communities where external hernia is commonest while adhesive or tumour obstruction is rare; however, these racial groups do not exhibit the high incidence of intussusception and volvulus found in Africa and India. The operative mortality was 13-9 per cent, which is comparable to that in Western series. The major adverse factors in intestinal obstruction, i.e. extremes of age, associated disease, gangrenous bowel, large bowel obstruction and malignancy, were confirmed. Fluid and electrolyte imbalance was frequent, as in other tropical series, but with intensive preoperative correction it was not an important adverse factor.
MeSH terms: Adolescent; Adult; Aged; Child; Child, Preschool; Humans; Infant; Infant, Newborn; Malaysia; Male; Middle Aged; Continental Population Groups