The main objective of this study was to survey the prevalence of hypertension in Malaysians aged 55 years and above who responded to a public health screening campaign in Kuala Langat district, Selangor, Malaysia. The relationship between the detection, treatment and control in the study population was also examined. An epidemiological survey of the elderly was conducted in Kuala Langat, a rural district in Malaysia for a consecutive period of six weeks. The survey was conducted using a standardized questionnaire and interview by trained research assistants. The medical students and nurses were trained on the correct protocol of measuring blood pressure based on the recommendations of the British Hypertension Society. Newly detected persons with blood pressure readings 160/95 mmHg and above, were given a green card to return to the nearest health center for a further 2 visits to check his/her blood pressure. A total of 1,392 people with a mean age of 65 years and comprising of 53.1% males and 46.9% females responded to the health survey. Based on the history 335 (24.1%) of the respondents were known hypertensives and 82.1% of this hypertensive group were on regular treatment. However good control of hypertension was achieved only in 161 (48.1%) of them. Newly detected hypertension was found in 204 (14.6%) of the respondents. The overall prevalence of hypertension in our sample of respondents was 25.6%. There was no significant difference between the sexes and the races in terms of their detection, treatment and control. However there was a significant difference between the persons aged less than 65 years of age and those older than 65 years. There was a large proportion of previously known hypertensives among the survey population. Of those detected, not all were on regular medications and the majority on medications were not well controlled. Education of the public through intensive public health campaigns is vital to improve their knowledge on hypertension and the need for effective control. More community studies are needed to formulate better methods in the detection, treatment and control of hypertension.
Regular blood transfusions for patients with thalassemia have improved their overall survival although these transfusions carry a definite risk of the transmission of certain viruses. Infection with hepatitis B virus (HBV), hepatitis C virus (HCV), cytomegalovirus (CMV) and human immunodeficiency virus (HIV) leads to complications which contribute to the morbidity and mortality of patients with thalassemia. We analyzed the blood samples taken from 85 transfusion dependent thalassemics receiving treatment at the day care center in Hospital Universiti Kebangsaan Malaysia and found that the seroprevalence rates for HBV, HCV and CMV were 2.4%, 22.4% and 91.8% respectively. None of the patients tested positive for HIV. Those positive for HBV and HCV will require further tests and treatment if chronic hepatitis is confirmed.
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.
A study to determine the effect of antihelminthic treatment on growth and nutritional status was undertaken on 103 children in the second grade of primary school, 71 of whom were found to be infected with Ascaris lumbricoides or Trichuris trichiura. The median Ascaris and Trichuris intensities in the infected group were 19,600 (range; 0-488,000) and 2,800 (range; 0-84,600) eggs per gram of feces respectively. Forty-three children harbored both types of worm. Fourteen weeks after two 400 mg doses of albendazole were administered to infected children, the increases in weight, height, weight for age, height for age and weight for height were significantly higher among infected children than controls who were uninfected at baseline. The observed gains were independent of sex and socioeconomic status. Decrease in log transformed Trichuris intensity correlated with increases in weight (r=0.24; p=0.02) and weight for age (r=0.20; p=0.06) but decrease in Ascaris intensity did not correlate with increases in any of the anthropometric parameters. The results suggest that antihelminthic treatment has beneficial short-term effects on growth and nutritional status of a modest magnitude among early primary schoolchildren in the area.
Two formulations of lambda-cyhalothrin (EC-Emulsion concentrate and MC-Microencapsulated) were impregnated into bednets made of polyethylene and polyester. The nets were treated at a dosage of 15 mg/m2. For bioassay of insecticidal efficacy, female Anopheles maculatus and Aedes aegypti were exposed to the nets for two minutes and mortality was scored 24 hours later. The nets were also tested after repeated washings with water and with soap and water. Microencapsulated (2.5CS) formulation was more effective than emulsion concentrate (2.5EC) formulation on both net materials--polyethylene and polyester. Repeated washing with water and soap reduces the efficacy of all bednet treatment combinations. Microencapsulated formulation on polyethylene gave best results; it could sustain up to five washes with water and two with soap and water.
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.
Adult immunization is a neglected and underpublicised issue in Southeast Asia. Vaccine-preventable diseases cause unnecessary morbidity and mortality among adults in the region, while inadequate immunization results in unnecessary costs, including those associated with hospitalization, treatment, and loss of income. Childhood vaccination coverage is high for the EPI diseases of diphtheria, tetanus and pertussis; however, unvaccinated, undervaccinated, and aging adults with waning immunity remain at risk from infection and may benefit from vaccination. Catch-up immunization is advisable for adults seronegative for hepatitis B virus, while immunization against the hepatitis A and varicella viruses may benefit those who remain susceptible. Among older adults, immunization against influenza and pneumococcal infections is likely to be beneficial in reducing morbidity and mortality. Certain vaccinations are also recommended for specific groups, such as rubella for women of child-bearing age, typhoid for those travelling to high-endemicity areas, and several vaccines for high-risk occupational groups such as health care workers. This paper presents an overview of a number of vaccine-preventable diseases which occur in adults, and highlights the importance of immunization to protect those at risk of infection.
The Filariasis Control Program was established more than 30 years ago in the country and the disease is still a public health problem in some states. Since 1983, a total of 17 filariasis control teams were formed throughout the country to carry out filariasis control work. The teams conduct house and population censuses, nocturnal mass blood surveys and treatment of microscopically confirmed cases. Individual case follow-up is being carried out after 3-5 months while the locality is resurveyed after about 2-3 years. During the years 1988 to 1990, there appeared to be a decreasing trend in the number of filariasis cases detected countrywide. In 1991, brugian filariasis accounted for 92% of the cases detected. The microfilaria rate (MFR) also showed a decreasing trend countrywide for the years 1988 (0.57%) to 1990 (0.35%) but there was an increase in 1991 although it remained well below the 5% MFR targeted in the program objective, In 1991, the filariasis control teams and the district multi-purpose teams collected a total of 167, 151 blood slides out of which 871 were found to be positive for microfilaria. To determine the true endemicity of filariasis in the country, the malaria district multi-purpose teams are also utilized to assist in probe surveys in new areas of the district. Two species of filarial worms, namely Brugia malayi and Wuchereria bancrofti, and the mosquito vectors belonging to the Anopheles and Mansonia genera are involved in the transmission of filariasis in Malaysia. Monkeys and domestic cats are the reservoir hosts for the subperiodic strain of B. malayi.
A novel method for the control of Mansonia larvae was developed and tested. In this method, foliar absorption and translocation of a chemical insecticide, monocrotophos, a known systemic insecticide was studied in the Eicchornia plant. Acetone solution of the insecticide was painted onto leaves of the plant. At daily intervals, stems were severed and divided into equal sections which were introduced into bowls. Larvae of Aedes aegypti were tested for the presence of monocrotophos. It was found that translocation of the insecticide occurred at different rates in the stems and in some plants the chemical was also released into the surrounding water. Based on these results, 2 insecticides namely, monocrotophos and temephos were painted onto leaves of the host plant and their translocation to the root and water environment was examined by testing with Mansonia and Aedes aegypti larvae. The results again confirmed the translocation process and it was found that the insecticides were secreted into the surrounding water, thereby killing the larvae. However, in leaves painted with permethrin (synthetic pyrethroid) or flufenoxuron (chitin synthesis inhibitor), such a process was not detected. The potential of this new concept in Mansonia larval control is examined.
Two monoclonal antibodies (MAbs), one produced against Plasmodium falciparum (PF-IG8) and the other against P. cynomolgi (PC-IE12) schizont antigens were used in a sandwich ELISA for the detection of circulating plasmodial antigens in sera of patients infected with either P. falciparum, P. vivax or P. malariae. The mean +/- SD optical density (OD) values for the normal control group using PF-108 and PC-1E12 were 0.351 +/- 0.036 and 0.205 +/- 0.044, respectively. Mean OD values for the three infected groups were found to be significantly higher than those of the normal control group for both MAbs. However, ELISA values for individual serum specimens did not correlate with the level of parasitemia in the infected blood. Using a cut-off point of mean OD +/- 3 SD of the normal control group as indicating a positive reading, the specificity of this assay with both MAbs was 100%. The sensitivity of the assay using PF-1G8 was 95% while that obtained with PC-1E12 was 98%.
The highly sensitive AFRIMS format IgM capture ELISA for the diagnosis of dengue virus infections requires the use of mouse brain derived hemagglutinins and consequently also the use of 20% acetone extracted normal human serum to eliminate high background. These reagents are not always easily available and we have thus compared the AFRIMS format with another published format which uses cell culture derived antigens (culture fluid, CF, format) in order to determine if it is reasonable to use cell culture derived antigens in situations where hemagglutinins and normal human serum are difficult to obtain. The study shows that using AFRIMS results as the reference point, the CF format described here has a sensitivity of 90% and a specificity of 96%.
The control of dengue outbreak requires a multi-pronged effort by the various government agencies. It requires co-operation of the community in the control activities, strict adherence to existing control procedures and guidelines by health personnel, increased manpower where necessary and strengthening co-operation between various health agencies to prevent delay in instituting control measures.
The ability to identify the occurrence of different resistance genotypes in field populations of mosquito is considered important for the purpose of optimising chemical control operations. The recent development of rapid microassays of enzymes responsible for resistance has provided a means for rapidly assessing the genetic background of target mosquito populations. This concept is the topic of investigation in this study. Non-specific esterase activity, which is responsible for the resistance to organophosphates in Malaysian Culex quinquefasciatus Say adults, was determined in 3 field populations from Kuala Lumpur City using rapid enzyme assay. The optical density results were used to estimate the genotypic frequencies of the populations. Subsequently, time-dependent changes in the various frequencies were determined. Such techniques allowed rapid assessment of resistance genotypes for decision-making and its possible use in insect control merits further investigation.
Spirometry was performed on 1,485 male subjects ranging in age from 13 years to 78 years and comprising of all the main ethnic groups in Malaysia. They were divided into six age categories. Mean forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) were 3.45 +/- 0.02 and 3.10 +/- 0.02, respectively. Both FVC and FEV1 correlated negatively with age. Regression analysis revealed an age-related decline in FVC of 295 ml per decade of life. Multiple stepwise regression of the data for the prediction of an individual's FVC above the age of 20 years gave the equation FVC (1) = 0.0404 (height in cm)-0.0295 (age in years)-2.2892. Predicted FVC values derived from equations based on other populations were considerably higher than the observed mean in this study. This study therefore, reemphasises the need to be cautions when applying formulae derived from one population to another. Grossly erroneous conclusions may be reached unless predicted equations for lung-function tests for a given population group are derived from studies based upon the same population group.
Two commercial serological kits, Pylori-set (Orion Diagnostica, Finland) and Helico-G (Cambridge Biomedical Ltd, UK), and an in-house ELISA were evaluated with sera from 24 Helicobacter pylori-positive and 146 H. pylori-negative dyspeptic patients. Sensitivity, specificity, positive and negative predictive values of Pylori-set were lower than that of Helico-G and in-house ELISA. Helico-G was more sensitive (91.7%) than in-house ELISA (83.3%) and both had comparable negative predictive values of 98.3% and 97.3%, respectively. However, specificity (97.9%) and positive predictive value (86.9%) of an in-house ELISA were much higher than specificity (80.1%) and positive predictive value (43.1%) of Helico-G. Kappa index of agreement between the three serological tests (Pylori-set, Helico-G or in-house ELISA) and the presence of H. pylori in antral biopsies was very low (k = 0.13; z = 1.9; p > 0.05), moderate (k = 0.49; z = 7.1; p < 0.0001), or substantial (k = 0.82; z = 10.8; p < 0.0001), respectively. Overall, statistical evaluations demonstrated that both commercial kits were not as reliable as the in-house ELISA for serodiagnosing H. pylori infection.
The prevalence and intensity of soil-transmitted helminths in five rural villages in northern peninsular were investigated. Generally the prevalence and intensity of infection were low in the 0-10- and above 50-year-old age groups when compared with other age groups. The prevalence and intensity of infection in the five villages were quite similar, because of similar socio-economic status. The highest intensity was observed for Ascaris lumbricoides, followed by hookworms and Trichuris trichiura.
Dengue viruses pose a considerable global public health problem with an estimated 100 million cases of illness every year. This illustrates the need for rapid and reliable diagnostic methods for proper patient management and disease control. Currently, laboratory diagnosis depends on serology or virus isolation, with both methods having certain drawbacks. Alternatively, reverse transcription and polymerase chain reaction (RT-PCR) offers the potential for the rapid, highly sensitive and specific detection of dengue viruses. Since we occasionally encounter the problem of insufficient amounts of patient serum for the direct detection of dengue viruses, a method was developed for the extraction of viral RNA after biological amplification in mosquito larvae. Using this method, 15 of 19 clinical samples tested were correctly identified using RT-PCR.
A questionnaire survey to study the smoking habits and attitudes toward smoking among secondary school teachers in Kelantan, Malaysia was conducted between July and September 1992. Questionnaires were sent to 5,112 teachers through their respective headmasters. Sixty-three percent (3,208 teachers; 61% males, 39% females) responded satisfactorily. Overall, 625 teachers (20%) were current smokers, 141 (4%) were occasional smokers, 317 (10%) were ex-smokers and 2,123 (67%) had never smoked. Only six (0.8%) of the 766 regular and occasional smokers were females. The rates of smoking among parents and siblings of smokers were higher than parents and siblings of non-smokers. Seventy-four percent of the smoking teachers admitted to smoking in the school premises. The teachers' attitudes about the health effects of smoking were statistically different between smokers and non-smokers. However, both smoking and non-smoking teachers had similar views regarding methods to control the smoking habit which included banning cigarette sales, putting a halt to the tobacco industry and banning cigarette advertisements.