Current World Environment

Introduction

Dengue is a viral disease transmitted to humans by the bite of infected females of the main vector Aedes aegypti and to lesser extent Aedes albopictus mosquitoes.¹ The World Health Organization has classified dengue into three categories according to disease severity; Dengue Fever (DF), Dengue Hemorrhagic Fever (DHF), and Dengue Shock Syndrome (DSS).² Severe dengue (DHF and DSS) causes lethal complications that included severe hemorrhage, plasma leakage, organ impairment, fluid accumulation, or respiratory distress.^{3, 4} The four genetically related viruses that cause dengue are single-stranded RNA, belonging to the Flaviviridae family and genus Flavivirus.⁵ These four viruses were designated as DEN-1, DEN-2, DEN-3, and DEN-4.²

Globally, the disability-adjusted life years (DALYS) were estimated as 750.000 per annum lost years of healthy life due to dengue. The loss is mainly due to immobilization, absenteeism, or debilitation. ^{6, 7, 8}

In some parts of the world (e.g. Americas), losses caused by dengue to the economies of these countries are similar to that caused by tuberculosis and malaria.⁹ In Thailand, Malaysia, and Cambodia, the economic losses attributed to dengue are as much as $89 million,¹⁰ whereas, the loss is estimated to be $2.1 billion in the Caribbean and Latin America.¹¹

The incidence of DF has increased more than 30 fold over the last five decades, thus, the dengue virus (DENV) infection has globally become a major public health threat. DF is now endemic in128 countries.¹² According to Bhatt et al.,¹³ 390 million DENV infections are estimated to occur per year; over three times more than previous estimates by the World Health Organization (WHO) had suggested.¹⁴ Although some progresses had been achieved towards the development and clinical evaluation of vaccines against DENV infection, no such vaccine is on the market yet¹⁵ and there is no specific treatment against DF. Thus, controlling the populations of DENV vector mosquitoes, especially Aedes aegypti and Aedes albopictus, and limiting their dispersal to new regions is crucial to prevent DENV transmission.¹⁶

Case fatality rate of DHF is 5% in most countries and this rate is expected to increase during epidemics.

In Saudi Arabia, Jeddah has witnessed the first cases of DF in 1994 with DENV-2. Shortly after that, virus surveillance revealed 3 dengue serotypes.¹⁷ Endemicity of DF in Jeddah has been confirmed by Ministry of Health in the last decades and 1551 positive cases were notified in 2006 -2007 with 1.1% and 0.5 % of DHF and DSS cases, respectively.¹⁸

Jazan region, on other hand, had registered 832 confirmed DF cases in the period from 2005 to 2014 with the highest cases being in 2010 (290 cases). Alazragi et al .¹⁹ conducted study in Jazan to measure seroprevalence of dengue virus (DENV) infection among 965 persons. A seroprevalence of 31.7 % (306/965) for DENV specific IgG was found. They revealed that the significant risk factors were: age ≥20 years, being male, lack of electricity and having water basins in the house.

Ibrahim et al .²⁰ conducted a study to investigate knowledge, attitudes and practices (KAPs) relating to dengue fever among females in Jeddah high schools. They concluded that KAPs towards DF was deficient among target populations, especially students.

It is well known that the ecology and epidemiology of DF are pretty associated with human habits. Therefore, assessment of people's knowledge, attitude, and practice is an important tool in preventing the disease and it is also a vital component of the integrated vector control programmes. ²¹

In Jazan, the variation in local, community-level, environmental and socio-behavioral drivers have rarely been carefully investigated. In particular, the importance of people’s knowledge, attitudes and practices (KAP) concerning DF prevention in these local contexts is poorly understood. In addition, there is a lack of relevant studies on the KAPs in Jazan region. Only one study by Bani et al ²² has been published on the topic but it focused primarily on households KAPs towards dengue.

Therefore, significant gaps in the literature on levels of awareness of students of Jazan on the KAPs of dengue fever are existed. The present study aimed to evaluate the knowledge, attitudes and practices regarding dengue infections among students of secondary schools in Jazan, Kingdom of Saudi Arabia (KSA).

Materials and Methods

Study subjects and sample

The present study was conducted using a cross-sectional approach ²³ in August 2015. This study design is appropriate as the main objective of this investigation was to assess the knowledge, attitudes, and practices regarding DF among school students.

Six secondary schools were randomly selected (five in Jazan – 3 boy's schools and 2 girls' schools – and one in Samtah around 60 km south of Jazan).

Multistage stratified random sample method²⁴ was used to select the students sample by dividing schools according to geographic districts (north, south, east and west of Jazan city, in addition to Samtah to represent sub-urban schools), educational grade (first, second and third year). In addition, all teachers who were available in the selected schools on the day of interview and agreed to participate were also included in the study. A total of 742 respondents participated in this study (vast majority are student beside some few teachers).

The team followed the ethical standards of confidentiality and freedom to participate.

The respondents were told that the research was voluntary and that they could choose to withdraw, and they were assured that their privacy and confidentiality would be protected.

Questionnaire

In addition to the socio-demographic information (age, sex, marital status, education level and employment), the questionnaire consists also of:

Respondents' knowledge

Multiple choices questions (MCQs) consisted of 32 items concerning the prior history, transmission methods, Symptoms, treatment, main vectors, mosquito's biting time, mosquito's breeding sites and vector's controlling methods of DF were used.

Respondents' attitudes

As the dengue fever is considered a significant public health problem in Jazan region, respondents attitudes on their roles in DF prevention and control, responsibility of DF control, and their agreement on other preventive and control measures of DF were sought.

Respondents' self-reported practices

Participating with your community in DF control campaigns, investigating and cleaning breeding sites in water filled containers under air conditions, covering water containers, disposing larvae from breeding containers, investigating Aedes larvae in water of cans and bottles around home, weekly changing of animal drinking water and disposing garbage in allocated garbage bins were reported by the respondents.

Statistical Analysis

The collected data from the questionnaire were coded, reviewed and entered into a computerized data base and analyzed using SPSS, version 18 (SPSS Inc, Chicago, Ill., USA). Frequencies and percentages (descriptive statistics) were used for analyzing the selected socio-demographic data, while the means and t-test were used to assess responses of the participants on the questionnaire regarding practice scores in relation to demography. Chi-squared test was used to determine the significance of the relationship between socio-demographic characteristics and knowledge on DF, as well as, to assess the responses of the participants as for the sources of their information on DF.  A p-value of equal to or less than 0.05 was considered statistically significant.

Results

Socio-demographic characteristics of the study population of Jazan secondary schools

The socio-demographic characteristics of the respondents as obtained during the KAP student survey in Jazan secondary schools are illustrated in Table 1.

A total of seven hundred forty two (742) respondents were recruited to participate in the investigation consisting of 555 (74.8%) male and 187 (25.2%) female. Majority of the respondents belong to the age group of 16 to 20 years old (n = 664, 89.5%) and not married (n = 686, 93%). As to education, the majority of the respondents were at secondary level (n = 686, 92.5%). Of the total study respondents, 94.1% were unemployed and 5.9% were employed.

Table 1: Socio-demographic characteristics of the respondents (N=742)

Knowledge of students on different dengue fever items:

Only 26 (3.5%) of the research participants had prior history with DF (Table 2). More than half of the respondents knew that dengue is caused by a mosquito bite (n = 430, 58%), and it is more likely to feed/bite in the night (n = 403, 56%). While, 42% of the respondents do not know what are the methods of DF transmission. Less than half of the respondents cited that a person with dengue infections may develop typical symptoms of fever (n= 343, 46.7%), similarly less than half also (n= 348, 47.4%) do not know what are the symptoms of the DF.

As for the knowledge on DF treatment, 440 of the respondents (60%) knew that DF is curable, whereas 40% of them do not know.

More than half of the respondents do not know the principal vector of dengue fever (n= 477, 65%), while only little portion of them knew the vector (n= 256, 35%).

Major proportion of the respondents cited swamps and ponds to be the DF mosquito's breeding sites, followed by sewage water and containers under air conditions (n= 509, 70.1%; n= 264, 36.3%; n=164, 22.6%), respectively.

As far as DF's vector control methods is concerned, most of the respondents reported insecticides (n = 426, 72.3%), then covering water tanks (n = 193, 32.8%) and using repellents (n =183, 31.1%).

Attitudes towards dengue fever

Respondents' attitudes towards DF are shown in Table 3. Vast majority of the respondents believed that DF could be prevented and controlled (n= 680, 93.2%) and they also cited that the control of DF is the responsibility of both government and community (n= 599, 83.1%).

Great proportion of the respondents does not think that elimination of breeding sites of the DF vector is complicated and time consumer process (n= 527, 71.7%). Less than half of the respondents do not know whether fogging is the only control method against DF or no, whereas more than third disagreed that it does. High percentage of the respondents thought that it is possible to recover from DF infection (n= 545, 74.5%).  Around forty one percent of the respondents disagreed that healthy person cannot be infected by DF, while one third of them agreed.

In this study, it was found that three quarters of the respondents agreed that they have an important role to play in DF prevention (n= 573).

Self-reported preventive measures against dengue fever

Most of the respondents employed environmental preventive measures to reduce mosquitoes and hence dengue fever (Table 4). For example, the majority of the respondents disposed larvae from breeding containers (n = 618, 85.5%), covered water containers (n = 502, 68.6%), disposed garbage in allocated garbage bins (n = 400, 66%), and participate with the community in DF control campaigns (n = 457, 63.6%). While only about one third investigated Aedes larvae in water of cans and bottles around home or weekly changed the animal drinking water (Table 4).

Practice Vs Socio-Demographic characteristics

Socio-demographic characteristics in relation to DF preventive practices are illustrated in Table 5. As gleaned on the table, means and test statistics show that only the gender characteristic is predictor of practice against DF (female mean=.1.7672 ± 0.25, male mean=1.6287± 0.33) However, there is a highly significant difference between females and males in their practice ( t = 4.247 , P<0.005).

Source of knowledge on DF among the respondents

Respondents' sources of information about dengue are presented in Table 6.  Less than half of the respondents or 48.1% and 44.5% cited Primary Health Care (PHC) and television as their main sources of information on dengue fever, respectively. However, no significant difference was found between the respondents regarding their answers on PHC (P>0.005). Third of the respondents found their information on dengue from Pamphlets. In addition, few respondents obtained such information from Radio, Friends or Relatives.

Table 2: Knowledge of the respondents*

Multiple responses. 

Table 3: Attitudes of the respondents

Table 4: Self-reported prevention practices among the respondents

Table 5: Prevention Practice Vs Socio-Demographic characteristics

Table 6: Sources of knowledge on DF

Discussion

The present study evaluated the knowledge, attitude and preventive practices regarding dengue fever among secondary schools students in Jazan, Saudi Arabia.

Our current study illustrates that only 3.5% of the respondents have a prior history of DF. This presumably justify that the respondents could not point out typical symptoms of dengue because they had not witnessed a case from a close relative or community's member nor had they personally experienced the disease. This in turn means that the disease may easily be undetected or confused with other similar causes of fever like influenza, typhoid, etc. leading to delays in accessing health care centers and eventually to DF complications.²⁵

More than half of the respondents (58%) in the present study have correctly identified mosquito bites as a transmission route. This result is in close relation to other studies conducted in Brazil (60.8%)²¹ and Philippines (68.7%).²⁶ In contrast, higher percentages of correct answers than those of the present study were reported from Jeddah, Saudi Arabia (88.8%)²⁰ and 95.8% obtained from Hong Kong.²⁷ More than third of respondents in the present study do not know what is the method of DF transmission indicating the need for educational campaigns.

Less than half of the respondents cited fever as the most common symptom of DF. This finding concurs with other studies carried out in Saudi Arabia,²⁰ India,²⁸ Hong Kong,²⁶ Brazil,²¹ Pakistan,²⁹ northern Thailand³⁰ and Cambodia.³¹ It is also worthy to note that 47.4% of the respondents do not know the DF symptoms although 60% of them agreed that DF is curable. However, isolated knowledge on symptoms may be considered somewhat adequate. Good knowledge of signs and symptoms of DF is essential in identifying the disease and to seeking early appropriate health care to save life.³²

Surprisingly, more than half of respondents (56%) were unaware that dengue mosquitoes are more likely to bite in the afternoon; instead they reported night as the mosquito's biting time. Only 6.7% of respondents correctly identified the morning time. World Health Organization¹ pointed out that Aedes mosquito usually bites during the day. Moreover, majority of respondents (70.1%) correctly cited swamps and ponds as mosquitoes' breeding sites, while 36.3% of them were unaware and reported sewage water. Bridging this gap in knowledge in vector biology is important in planning and designing programs and activities to educate rural residents on preventive measures to combat dengue.

Regarding the knowledge on the mosquito controlling methods, it was found that the use of insecticides sprays, covering water tanks and use of mosquito repellents were the most commonly preferred preventive practices (72.3%, 32.8% and 31.1%, respectively). This finding is in accordance with the study conducted in Jazan²² where it revealed that 81.2% of the participants prefer to use spray to keep mosquitoes away. Itrat et al ²⁹ in Pakistan revealed that mosquito sprays was considered the most common choices for prevention. Conversely in Philippines, only a little proportion of the respondents reported the use of pesticides.³²

This investigation illustrates a poor overall DF knowledge among the secondary school students in Jazan. This may be attributed to the fact that the disease is only recently emerged in Jazan, Saudi Arabia, compared with other countries where the disease has been endemic for decades. This result coincides with the findings of Ibrahim et al ²⁰ in Jeddah Saudi Arabia.

As to attitudes towards DF prevention and control, the majority of the respondents were having good attitudes and believed that DF could be controlled and prevented (93.2%), DF control is the responsibility of government and community (83.1%) and they themselves have an important role to play in DF prevention (78.5%). This on the other hand shows that the majority of the students had perceived a risk and health threat of DF and seemed supportive towards DF control and prevention.³³

Concerning the self-reported prevention practices against DF, the most common practice to prevent mosquito breeding was found to be the disposing of water from breeding containers (85.5%). This is in accordance with the finding of Dhimal et al. ³³ in Nepal where 91% of the participants cited this practice to be useful in reducing the number of mosquitoes. While in Brazil, the most commonly reported preventive practice was elimination of water containers.²¹ The second common DF preventive measure used by the respondents in the current study was the covering of water containers (68.6%). In Thailand, a survey of KAP of the prevention of DHF pointed out that covering water containers was the most common practice to prevent mosquito breeding in drinking-water containers.³⁴ Disposing garbage in allocated garbage bins (66%) and participating with community in DF control campaigns (63.6) were also some of the preventive practices reported by the respondents in the present study.

We found a significant association between the practice of DF preventive and control measures and the gender (sex) of the respondents (P<0.005). While in central Nepal, Dhimal et al ³³ revealed that education level was associated with good practices among the respondents who had completed secondary or higher secondary education.

Contrary to this, a lack of significant association between socio-demographic factors and practice level was observed in Malaysia and Jamaica.^35,25

In the current study, the most common source of DF knowledge came from primary health care centers (PHCs) and television. These selected sources of disseminated information may reflect the impact of Saudi Arabian DF public educational campaigns launched in Jazan region. A round 45% of the respondents cited television as a source of their information, correlating with data gathered from Saudi Arabia,²² Kuala Lumpur,³⁵ Thailand ³⁴ and partially coincides with the findings of Ibrahim et al ²⁰ in Jeddah, Saudi Arabia. Conversely, lower percentages of participants cited radio, newspapers and magazines, friends and relatives as their primary sources of information about the disease. This may reflect the importance of targeting future educational campaigns in these areas by the government in order to change behaviors and effectively communicate DF preventive measures through information, education and communication (IECs).

Conclusion

Low prevalence of sufficient knowledge was evident among secondary school students in Jazan. Nevertheless, isolated knowledge on symptoms, attitudes and prevention measures may be considered somewhat adequate. Good practice to prevent DF was related the gender.

The popular preventive measures were mainly the disposing of water from breeding containers and covering water containers.

It is evident from this study that primary health care centers (PHCs) and television were the most important source of information on DF among the study population. Based on this result, government authorities should strengthen its programs on massive educational campaign to increase awareness and knowledge regarding dengue and preventive measures to reduce mosquito and prevent dengue. Information, education and communication (IECs) materials maybe provided in areas like schools and health centers to make it more accessible for the residents to obtain. Knowledge of dengue, the vectors and transmission of disease may be incorporated into the school and university curriculum especially in areas where dengue is highly prevalent like Jazan. More intersectoral coordination should be obtained to identify possible partners for public education dengue control campaigns. Training of school teachers and community health workers should be conducted regularly to improve their technical skills and capabilities to supervise prevention and control activities.

Conflict of interest

The authors declare that they have no competing interests.

References
     

1. WHO Dengue: guidelines for diagnosis, treatment, prevention and control- New edition. WHO/HTM/NTD/DEN/2009.1. 2009.
2. WHO Dengue haemorrhagic fever: diagnosis, treatment, prevention and control. 2^nd Geneva,WHO, 1997, 48-59.
3. WHO Post Introduction Evaluation of Rotavirus Vaccine in Sudan.2012 [Online]. Available from: http://apps.who.int/iris/bitstream/10665/94371/1/201273%20EMR%20EPI%20RotavirusVaccine%20Rpt%20SudanDec2012.pdf?ua=1,(Accessed: 10/05/2015).
4. TDR 2012 [Online]. Available from: http://apps.who.int/tdr/svc/diseases/dengue. (Accessed 9/05/2015).
5. Heinz, F. X., Collett, M. S., Purcell, R. H., Gould, E. A., Howard, C. R., Houghton, M., Moormann, R., Rice, C. M., and Thiel, H. J. Family flaviviridae. In van Regenmortel, , Fauquet, C. M., Bishop, D. H. L., Carstens, E. B., Estes, M. K., Lemon, S. M., Maniloff, J., Mayo, M. A., McGeoch, D. J., Pringle, C. R., and Wickner, R. B., editors, Virus Taxonomy: Seventh Report of the International Committee on Taxonomy of Viruses, Academic Press, San Diego, 2000, Part Three, 859–878.
6. Clark, D., Mammen Jr, M., Nisalak, A., Puthimethee, V., and Endy, T. Economic impact of Dengue Fever/Dengue Hemorrhagic Fever in Thailand at the family and population levels. American  Journal of  Tropical Medicine and  Hygiene, 72(6):786–791.
7. Murray, C. J. L. and Lopez, A. D. Global health statistics: global burden of disease and injury series, volume II. Harvard School of Public Health, Boston. 1996a.\
8. Murray, C. J. L. and Lopez, A. D. The global burden of disease: global burden of disease and injury series, volume I. Harvard School of Public Health, Boston. 1996b.
9. Torres, J. R. and Castro, J. The health and economic impact of dengue in Latin America. Cadernos deSaúde Pública, 23(Suppl. 1):23–31. 2007.
10. Suaya, J., Shepard, D., Siqueira, J. a., Martelli, C., Lum, L., Tan, L., Kongsin, S., Jiamton, S., Garrido, F., Montoya, R., Armien, B., Rekol, H., Castillo, L., Caram, M., Sah, B., Sughayyar, R., Tyo, K., and Halstead, S. Cost of Dengue Cases in Eight Countries in the Americas and Asia: A Prospective Study. American Journal of Tropical Medicine and Hygiene, 80(5):846–855.
11. Shepard, D. S., Coudeville, L., Halasa, Y. A., Zambrano, B., and Dayan, G. H. Economic Impact of Dengue Illness in the Americas. American Journal of Tropical Medicine and Hygiene, 84(2):200–207. 2011.
12. Brady OJ, Gething PW, Bhatt S, Messina JP, Brownstein JS, et al. Refining the global spatial limits of dengue virus transmission by evidence-based consensus. PLoS Negl Trop Dis 6:e1760. 2012.
13. Bhatt S, Gething PW, Brady OJ, Messina JP, Farlow AW, et al. The global distribution and burden of dengue. Nature 496: 504–507. 2013
14. WHO/TDR Dengue: guidelines for diagnosis, treatment, prevention and control. Geneva: World Health Organization (WHO) and the Special Programme for Research and Training in Tropical Diseases (TDR). 2009.
15. Halstead SB. Dengue vaccine development: a 75% solution? Lancet 380: 1535–1536.
16. WHO/SEARO Comprehensive guidelines for prevention and control of dengue and dengue haemorrhagic fever (revised and expanded edition). New Delhi: World Health Organization, Regional Office for South East Asia. 2011.
17. Fakeeh, M., and Zaki, A.M. Virologic and serologic surveillance for dengue fever in Jeddah, Saudi Arabia, 1994-1999. Am J Trop Med Hyg, 65 (6): 764-767. 2001.
18. Elmusharaf N, Akbar N. Dengue and dengue hemorrhagic fever epidemic in Jeddah2006 2007. The Second International Conference on Dengue and Dengue Haemorrhagic Fever. 2008.
19. Al-Azraqi TA, El Mekki AA,  Mahfouz AA. Seroprevalence of dengue virus infection in Aseer and Jizan regions, Southwestern Saudi Arabia. Trans R Soc Trop Med Hyg. 107(6):368-71. 2013.
20. Ibrahim Nahla Khamis Ragab, Adnan Al-Bar, Mohamed Kordey, Ali Al-Fakeeh Knowledge, attitudes, and practices relating to Dengue fever among females in Jeddah high schools.  Infect Public Health, 2 (1). 30–40. 2009.
21. Degallier N, Vilarinhos PT, deCarvalho MS KnoxMS, Cae-tano JrJ. People’s knowledge and practice about dengue, its vectors, and control means in Brasilia (DF), Brazil: its relevance with entomological factors. Journal of the American Mosquito Control Association, 16:114—23. 2000.
22. Bani Ibrahim A., Anwar Makeen, Hussein M. Ageely, Waleed Milaat Knowledge, Attitude and Practices of Dengue prevention Jazan, Kingdom of Saudi Arabia (KSA). Annual meeting of the American society of tropical medicine and hygiene, November 19-22, 2009. Washington, D.C., USA.
23. Aday L. Designing & Conducting Health Surveys. ^2nd San Francisco: Jossey-Bass Publishers, 1996.
24. Aridaman K. Jain, and Robert E. Hausman. Encyclopedia of Statistical Sciences. DOI: 10.1002/0471667196.ess2604.pub2. 2006.
25. Shuaib F, Todd D, Campbell-Stennett D, Ehiri J, Jolly PE. Knowledge, attitudes and practices regarding dengue infection in Westmoreland, Jamaica. West Indian Med J 59: 139–146. 2010.
26. Mahilum MM, Ludwig M, Madon MB, Becker N. Evaluation of the present dengue situation and control strategies against Aedes aegypti in Cebu City, Philippines. Journal of Vector Ecology, 30:277—83. 2005.
27. Ho M, Luk Y, Choy RYL. Knowledge, attitude and practices of Hong Kong residents for dengue fever prevention. The Hong Kong Practitioner, 28:68—75. 2006.
28. Jeelani, S., Sabesan, S., and Subramanian Community knowledge, awareness and preventive practices regarding dengue fever in Puducherry – South India. DOI: http://dx.doi.org/10.1016/j.puhe.2015.02.026.  2015.
29. Itrat A, Khan A, Javaid S, Kamal M, Khan H, Javed S, et al. Knowledge, awareness and practices regarding dengue fever among the adult population of dengue hit cosmopolitan. PLoS One; 9(3):e2620. 2008.
30. Van Benthem BH, Khantikul N, Panart K, Kessels PJ, Somboon P, et al. Knowledge and use of prevention measures related to dengue in northern Thailand. Med Int. Health, 7: 993–1000. 2002.
31. Khun S and Manderson L. Community and School-Based Health Education for Dengue Control in Rural Cambodia: A Process Evaluation. PLoS Negl Trop Dis 1(3): e143. doi:10.1371/journal.pntd.0000143. 2007.
32. Yboa, C. and Labrague, L. J. Dengue Knowledge and Preventive Practices among Rural Residents in Samar Province, Philippines Begonia. American Journal of Public Health Research, 2013, Vol. 1, No. 2, 47-52. 2013.
33. Dhimal M, Aryal KK, Dhimal ML, Gautam I, Singh SP, Bhusal CL, et al. (2014) Knowledge, Attitude and Practice Regarding Dengue Fever among the Healthy Population of Highland and Lowland Communities in Central Nepal. PLoS ONE 9(7): e102028. doi:10.1371/journal.pone.0102028. 2014.
34. Swaddiwudhipong W, Lerdlukanavonge P, Khumklam P, Koonchote S, Nguntra P, Chaovakiratipong C. (1992) A survey of knowledge, attitude and practice of the prevention of dengue hemorrhagic fever in an urban community of Thailand. The South east Asian Journal of Tropical Medicine and Public Health, 23:207—11. 1992.
35. Hairi F, Ong CH, Suhaimi A,Tsung TW, bin Anis Ahmad MA, Sundaraj C, et al. A knowledge, attitude and practices (KAP) study on dengue among selected rural communities in the Kuala Kangsar district. Asia-Pacific Journal of Public Health, 15:37- 43. 2003.