Health Risk Assessment of PM10 exposure among Malaysian Adult Population based on Physical Activity Pattern

Most health advisories related to outdoor physical activity during haze are general in nature. The advisories normally advise everyone to reduce or limit prolonged exertion or heavy exertion without mentioning the acceptable duration for performing outdoor physical activity causing difficulty for public to decide to stop or cancel a particular outdoor or sport event. The aim of this paper is to determine the acceptable duration for performing outdoor physical activity pattern based on API level. Health risk assessment approach that comprises of hazard identification, exposure assessment, dose-response, and risk characterization steps were used to determine the potential inhaled dose and risk associated with performing the physical activity during haze. We have considered many factors that include time spent for physical activity patterns for Malaysian adult, age, physical intensity-specific inhalation rate (m3/min), and the indoor/outdoor ratio of PM10. A hypothetical exposure scenario of PM10 was created using the breakpoints of PM10 concentration for the calculation of respective API levels. The association between physical activity pattern, API level and risk quotient were presented in the form of risk radar diagram. In general, based on the average estimate, everyone should avoid high intensity physical activity and moderate exertion when API reach > 175 and > 200 respectively. Whereas, based on the high estimate, everyone should avoid high intensity physical activity and moderate exertion when API reach > 135 and > 150 respectively. Below the said API, the duration for performing prolonged exertion and heavy exertion should be adjusted according to the API level as stated in the recommended maximum duration for performing physical activity. Reducing the physical activity is an effective strategy to lower the dose of inhaled pollutants and reduce the health risk during poor air quality. Based on the assessment, the recommended maximum duration for performing the physical activity based on API level was established as a guide for the authority or public to plan their activity during poor air quality.​

Health Risk Assessment of PM10 Exposure among School Children and the Proposed API Level for Closing the School during Haze in Malaysia

During haze, at what level should Air Pollutant Index (API) showed, public or private school be closed is not without controversy and is very much debated. Therefore, the aim of this paper is to objectively quantify the potential inhaled dose of PM10 associated with exposure at school and home microenvironments during haze. The result of the health risk assessment will be used to propose the API level for closing the school during haze episode. A hypothetical haze exposure scenario was created using the breakpoints of PM10 concentration for calculation of API and respective inhaled dose during haze. To determine the potential inhaled dose, we have considered many factors that include time spent for specific physical intensity at school and home microenvironments, age-specific and physical intensity-specific inhalation rate (m3/min), and the indoor/outdoor ratio of PM10. To calculate risk quotient (RQ), the inhaled dose was compared with the health reference dose computed based on the concentration of PM10 in the Malaysian Ambient Air Quality Standard. When considering the specific exposure at each microenvironment (school and home), the potential inhaled dose of PM10 was substantially lower when school is closed for both primary and secondary school. The calculated risk quotient (RQ) indicates that primary school children are likely to be affected at slightly lower PM10 concentration (equivalent to API of 197) as compared to secondary school children. Short duration of high physical activity intensity during school breaks has contributed to a large proportion of inhaled dose among school children indicating the important to avoid physical activities during haze. Based on the assessment, taking into account the uncertainty of risk assessment methodology, we proposed school to be closed when API reach 190 for both primary and secondary schools. These findings and recommendations are only valid for naturally ventilated school and applicable in the context of the current API calculation system and the existing Recommended Air Quality Guideline values in Malaysia. ​

Potential Health Impacts of Bauxite Mining in Kuantan

Bauxite mining is not known to most Malaysian except recently due to environmental pollution issues in Kuantan, Pahang. Potential impacts are expected to go beyond physical environment and physical illness if the situation is not controlled. Loss of economic potentials, and the presence of unpleasant red dust causing mental distress, anger and community outrage. More studies are needed to associate it with chronic physical illness. While evidences are vital for action, merely waiting for a disease to occur is a sign of failure in prevention. All responsible agencies should focus on a wider aspect of health determinants rather than merely on the occurrence of diseases to act and the need to emphasize on sustainable mining to ensure health of people is not compromised.

Investigation of hepatitis A outbreak in district of Manjung, Perak, Malaysia, October 2012

Background：In September 2012, 10 cases suspected to be hepatitis A were notified to the Manjung District Health Department. An investigation was conducted to identify the possible mode of transmission, source of the outbreak and to recommend prevention and control measures.Methods：A case was a person with acute illness with discrete onset of symptoms and jaundice or elevated serum aminotransferase levels in September 2012 in the Manjung District. We conducted a case-control study and environmental assessments of processing plants and food premises.Results：There were 78 confirmed cases of hepatitis A; an attack rate of 3.1 per 10 000 population. Multiple logistic regression showed that being male (odds ratio [OR]: 18.4 [5.13–65.9]; P < 0.001) and drinking toddy at processing place A (Adjusted OR: 2.70 [1.17–6.25]; P < 0.05) were associated with being a case. Environmental investigations of this and one other processing place found them to be unhygienic, and the pH of the toddy was at levels that encouraged growth of hepatitis A virus.Conclusion：Toddy was possibly the primary source of this outbreak based on both epidemiological and environmental results. Both toddy preparation places and several food premises were closed as a result of this investigation.

Responding to the Potential of Ebola Virus Disease (EVD) Importation into Malaysia

The current Ebola outbreak, which is the first to affect West African countries, has been declared to have met the conditions for a Public Health Emergency of International Concern (PHEIC) by the World Health Organization (WHO). Thus, the Ministry of Health (MOH) of Malaysia has taken steps to strengthen and enhanced the five core components of preparedness and response to mitigate the outbreak. The National Crisis Preparedness and Response Centre (CPRC) commands, controls and coordinates the preparedness and response plans for disasters, outbreaks, crises and emergencies (DOCE) related to health in a centralised way. Through standardised case definition and mandatory notification of Ebola by public and private practitioners, surveillance of Ebola is made possible. Government hospitals and laboratories have been identified to manage and diagnose Ebola virus infections, and medical staff members have been trained to handle an Ebola outbreak, with emphasis on strict infection prevention and control practices. Monitoring of the points of entry, focusing on travellers and students visiting or coming from West African countries is made possible by interagency collaborations. To alleviate the public’s anxiety, effective risk communications are being delivered through various channels. With experience in past outbreak control, the MOH’s preparedness and response plans are in place to abate an Ebola outbreak.

Surveillance For Sarcocystosis In Tioman Island, Malaysia

In October 2011, the National International Health Regulations (IHR) 2005 Focal Point for Malaysia received notification from the United States’ Centers for Disease Control and Prevention (CDC) of a probable Sarcocystis outbreak amongst 23 travellers from six countries who had vacationed on Tioman Island between June and August 2011. The Ministry of Health, Malaysia (MOH) in collaboration with the Department of Veterinary Services, Malaysia (DVS) conducted a cross sectional study in November 2011 to determine the presence of Sarcocystosis among humans, animals and in the environment in Tioman Island. Epidemiological investigations conducted involved a community health survey of 44 residents in Kampung Salang, Tioman and review of outpatient attendance cards for suspected or confirmed cases of Sarcocystosis. Twenty-eight fresh stool samples were collected and sent to the National Public Health Laboratory (NPHL) for detection of Sarcocystis oocysts using fluorescence microscopy. Water samples taken from 27 water sampling points around the island were processed and analysed under the fluorescence microscope using ultraviolet (UV) light at the Institute for Medical Research (IMR) to detect the presence of Sarcocystis sporocyst. DVS collected 84 faecal samples from four types of domesticated animals and then analysed them at the Veterinary Services Centre in Tioman Island for Sarcocystis oocysts and other parasitic ova and cysts using qualitative Floatation Technique. The results showed that Sarcocystis was not present in humans, animals and in the environment in Tioman Island during the study period. Further surveillance among humans, wildlife and the environment is needed to determine Sarcocystis endemicity in Tioman Island.

Validation of ICD 10 on congenital anomalies in the state of Penang

Background: Database on hospital records like discharge data, birth and death certificates are widely used for epidemiological and research studies. However there are a very few validation studies on these data. The aim of this study was to validate and assess the accuracy of the ICD 10 database on congenital anomalies in the state of Penang. This study was carried out for three years, from 2002 to 2004. Methods: The list of cases coded under the general coding “Q” was extracted and approximately 30% of cases were randomly selected from the list. Medical records for the selected cases were checked and discrepancies for the diagnoses between the medical records and the ICD 10 data base were recorded for three years. Verification was done for basic demographic variables and the coding of the diseases. Discrepancies, sensitivity and specificity were calculated. Results: The ICD 10 database for congenital anomalies are classified into two types: Type 1 and Type 2. Discrepancies on demographic information were found among the age of patients (babies with congenital anomalies). In Type 1, there was a discrepancy of about 0.02 % to 0.05% probability that a congenital anomaly case can be recorded as non congenital anomaly in the ICD 10. In Type 2 there was a discrepancy that a non-congenital anomaly was classified as congenital anomaly and this ranged from 26.7% to 50.0%. The sensitivity ranged from 96.85% to 97.98%, thus it can be concluded the ICD 10 database is highly sensitive while the specificity ranged from 50.00% to 78.57 %. In other words the ICD 10 is not accurate when classifying the non- congenital anomaly cases. A fair percentage of non-congenital anomaly cases were classified as CA in the ICD 10 database. Conclusion: Even though hospital databases are used as a baseline data for a number of research and epidemiological studies it cannot be used at face value. Validation of these data is necessary before any conclusions can be drawn or intervention measures are undertaken.

“Ulam-ulaman” Intake Among Adults from Various Ethnics in Selangor / Jurnal Sains Kesihatan Malaysia

A survey was conducted to investigate the level of consumption of ‘ulam’ in Selangor State among 252 adults (> 17years) (male 28.6%, female 71.4%) of major ethnics (Malays-51.6%; Chinese-30.5%; Indians-17.5%) with the mean age of 42.7 ± 13.9 years. Consumption data were collected using 24 hours duplicate samples together with questionnaire on perceptions of ‘ulam.’ Results showed that ‘ulam’ was preferred by majority of the subjects (82.1%), especially amongst Malays (92.3%). A total of 52% of the subjects consumed partially or boiled ‘ulam.’ Factors that affect their preferences on ‘ulam’ were the perception of therapeutic effects of the ‘ulam’ towards health, its good taste and unique aroma. The most consumed ‘ulam’ were cucumber (Cucumis sativus) (60.6%) ‘kacang botol’ (Psophocarpus tetragonolobus) (33%), Indian pennywort (Hydrocotyle asiatica) (31.5%), lettuce (Lactuca sativa) (27.6%), ‘petai’ (Parkia speciosa) (29%) and ‘ulam raja’ (Cosmos caudatus) (21.9%). The most preferred partially or boiled ‘ulam’ were tapioca shoot (Manihot esculenta) (31.5%), ocra (Hibiscus esculentus) (12.5%) and ‘jantung pisang’ (Musa sapientum) (20.1%). There was no significant difference (P > 0.05) amongst the three different ethnic groups on the consumption of ‘ulam’ and the median for total intake per day was within the range of 30-39 g/day. Ulam is a potential source for increasing vegetable consumption to meet recommendation by World Health Organization (WHO), which is 400 g per day.

Use of molecular tools to distinguish Entamoeba histolytica and Entamoeba dispar infection among the aborigines in Cameron Highlands

Amoebiasis is an infectious diseased caused by parasitic one-celled protozoan called Entamoeba histolytica. Numerous protozoa also can inhabit the gastro-intestinal tract of human. Majority of these protozoa are non-pathogenic commensals or only causes disease under certain circumstances. Morphologically, E. histolytica, the invasive form, share the same characteristic with the nonpathogenic form, E. dispar. Both strains can be distinguished by using DNA identification. Many previous researches in Malaysia only reported infection with E. histolytica infection. Therefore in this study we tried to classify infection among the aborigines in Cameron Highland as true E. histolytica or E. dispar by Nested Polymerase Chain Reaction (Nested PCR) and Restriction enzyme (RE) digestion. Results showed that 31 samples were positive by microscopic examination, however of these 28 (13.2%) samples were positive for E. histolytica and 12 (5.6%) samples were positive for E. dispar by molecular tools.