1. ORAL PRESENTATION Abdul MM, Azmi MT, Shamsul AS 16 th National Public Health Colloquium 25 th Nov 2009

2. THE INFLUENCE OF ENVIRONMENTAL RISK FACTORS AND INDIVIDUAL BEHAVIOURS ON MALARIA OCCURRENCE IN LAHAD DATU DISTRICT OF SABAH: A CASE CONTROL STUDY. RESEARCH TITLE :

3. CONTENTS Introduction Introduction Literature Review Literature Review Research Justification Research Justification Objectives Objectives Hypothesis Hypothesis Methodology Methodology Results & Discussion Results & Discussion Conclusion & Recommendations Conclusion & Recommendations References References 3

4. Introduction Recorded as early as 2700 BC in China (Cox 2002). “Mala aria” – bad air Vector-borne disease caused by protozoan parasites Caused by Plasmodium spp. Transmitted by female Anopheles mosquitoes Infection may results in wide variety of symptoms Uncomplicated malaria Severe malaria Curable disease if Diagnosed and treated promptly and correctly 4

5. Magnitude of problem Worldwide (WHO 2008) Lived at high risk area – half of human population 300 millions infected 1 million death Malaysia Decreasing trend since 1996 IR (M’sia) 2.67/10 000 (2004) IR (Sabah) 9.56/ 10 000 (2004) IR (Lahad Datu) 20.4/10 000 (2008) 5

6. Literature review Lansang et al. (1997) study showed that the risk of malaria is higher in person worked in high risk occupation. CHESTRAD (2000) study showed that low household income is associated with higher risk of malaria infection. Tedros et al. (2000) and Koram et al. (1994) suggested that individual without car or refrigerator more likely to suffer from malaria. Guthmann et al. (2001) showed individual with formal education more than primary level less likely to get malaria. 6

7. Literature review Tedros et al. (2000) study showed low risk perception towards malaria more likely to have high risk of malaria disease. Usage of repellant, mosquito coil or aerosol spray found to reduced risk of severe malaria (Snow et al. 1998). Several studies have suggested that the usage of insecticide-treated bednets able to reduce the incidence of malaria (Binka et al. 1996 & Alexander et al. 2005). Konradsen et al. (2003) showed house sprayed with indoor residual spray was a protective factor for malaria infection. 7

8. Literature review Incardona et al. (2007) showed association between history of movement to the jungle with malaria infection. House located >500 m from forest fringe is protective factor towards malaria (Brooker et al. 2004) Water bodies provide suitable habitat for malaria vector thus increase risk of infection (Guthmann et al. 2002) Konradsen et al. (2003) suggest house built without good structure and design will increase risk of malaria. 8

9. Research justification Sabah highest malaria case contributor in Malaysia Analytical study to determine the association between environmental & individual factors and malaria is rarely done lately (none in LD) The incidence of malaria is high in Lahad Datu Justifications 9

10. Conceptual framework 10

11. Objectives General To identify the association between environmental risk factors, risk perception and individual behaviours with malaria infection in Lahad Datu district of Sabah. Specific To determine the association between socioeconomic status, risk perception, and individual movement and preventive behaviours with malaria infection in Lahad Datu. To determine the association between environmental factors (presence of potential breeding sites and house’ structure and design) and malaria in Lahad Datu. 11

12. Methodology Approved Study Case (Vekpro) Control Interviewed using a structured Q Inclusion and Exclusion End DESIGNSTUDY TOOLS AnalysisResults No. of cases = 166 No. of controls = 166 Discussion & Conclusion 12

13. Area of study 13

14. Sample size Based on Hennekens et al. (1987) 14

15. Questionnaires Sociodemographic & Socioeconomic status Individual behaviours Preventive Movement Environmental risk factors House location House design &structure Risk perception (12 Q) Cut off point = 9 (75%) Chronbach α = 0.73 Pretested in OPD LD (Dec 07) BSMP status 15

16. Data analysis Analyzed using SPSS version 12.0 McNemar on-line calculator (Graphpad) Statistical analysis Descriptive analysis Bivariate analysis Conditional logistic regression 16

17. 17

18. Results: Demographic features FactorsCase n=166 N (%) Control n=166 N (%) Age Minimum Maximum Median Interquartile range Gender Male Female Mukim Silam Silabukan Bandar Segama Tungku Felda 15 70 26 12 134 (80.7) 32 (19.3) 59 (35.5) 42 (25.3) 37 (22.3) 12 (7.2) 10 (6.0) 6 (3.6) 15 70 26 12 134 (80.7) 32 (19.3) 59 (35.5) 42 (25.3) 37 (22.3) 12 (7.2) 10 (6.0) 6 (3.6) 18

19. Association of study variables with Malaria 1.Type of occupation Variable n=166 Control OR M Wald Adjusted OR 95% CI Case Occupation High risk Low risk n (%) 69 (41.6) 8 (4.8) 49 (29.5) 40 (24.1) 6.124.0334.141.04-16.57 Type of occupation was found to be associated with malaria. High risk occupation more likely to get malaria infection. Earlier studies support this association (Lansang, 1997; Chang 1997 ; Honrado & Fungladda 1994) 19

20. Association of study variables with Malaria 2.Risk perception score Risk perception score was found associated with malaria infection. Consistent with the studies by Tedros et al. (2000) and Onwujekwe et al. (2000) Level of education associated with risk perception scores (OR 45; 95% CI 18-108) Risk perception influenced by many factors. Variable n=166 Control OR M Wald Adjusted OR 95% CI Case Score Low High n (%) 18 (10.9) 6 (3.6) 83 (50.0) 59 (35.5) 13.834.8476.011.22-29.63 20

21. Association of study variables with Malaria 3.Indoor residual spray Variable n=166 Control OR M Wald Adjusted OR 95% CI Case Residual spray No Yes n (%) 17 (10.2) 11 (6.6) 70 (42.2) 68 (41.0) 6.363.9723.701.02-13.39 Respondents lived in a house with no IRS done are at higher risk of malaria infection compared to those lived in a house sprayed with insecticide. Consistent with studies by Guthmann et al. (2001) and Konradsen et al. (2003) 21

22. Association of study variables with Malaria 4.History of movement Variable n=166 Control OR M Wald Adjusted OR 95% CI Case Movement Yes No n (%) 25 (15.1) 6 (3.6) 37 (22.3) 98 (59.0) 6.173.9945.251.03-26.71 History of movement in the last two weeks was found to be associated with malaria. Consistent with studies by Honrado & Fungladda (1994) & Singhanetra-Renard (1986) Frequency, duration, place and purpose of movement were insignificant. 22

23. Conclusion Type of occupation, risk perception, indoor residual spray activity and history of movement in the last two weeks are risk factors for malaria infection in Lahad Datu district. 23

24. Recommendations Improve risk perception amongst community Strengthen health education and promotion Preventive measures when doing high risk jobs or moving into high risk area IRS as method of choice in malaria control measures in oil palm plantations/estates ex; Hiring private company 24

25. References Cox 2002. History of human parasitology. Clinical Microbiology Review. 15(4); 595-612. Greenwood, B.M. 1989. The microepidemiology of malaria and its importance to malaria control. Transactions of the Royal Society of Tropical Medicine and Hygiene: 83; 25-29. WHO. 2008. World Malaria Report 2008. World Health Organization Media Centre. http://www.who.int/malaria/mediacentre/wmr2008/malaria2008.pdf JKN Sabah. 2004. Laporan Tahunan Unit Rancangan Kawalan Penyakit Bawaan Vektor (RKPBV) Pejabat Kesihatan Kawasan Lahad Datu, Jabatan Kesihatan Negeri Sabah. Lansang, M.A.D., Belizario, V.Y., Bustos, M.D.G., Saul, A. & Aguirre, A. 1997. Risk factors for infection with malaria in a low endemic community in Bataan, Phillipines. Acta Tropica: 63; 257-265. CHESTRAD. 2000. NetMark regional Africa programme briefing book. Insecticide treated materials in Nigeria. NetMark. http://www.netmarkafrica.org/countries/nigeria/briefbook/nigeria_briefing_book.pdf Tedros, A.G., Haile, M., Witten, K.H., Getachew, A., Yohannes, M., Lindsay, S.W. & Byass, P. 2000. Household risk factors for malaria among children in Ethiopia highlands. Transaction of the Royal Society of Tropical Medicine and Hygiene; 94: 17-21. Koram, K.A., Bennett, S., Adiamah, J.H. & Greenwood, B.M. 1995. Socioeconomic risk factors for malaria in a peri-urban area Of Gambia. Transaction of the Royal Society of Tropical Medicine and Hygiene: 89; 146-150. Alexander, N., Rodriguez, M., Perez, L., Caicedo, J.C., Cruz, J., Prieto, G., Arroyo, J.A., Cotacio, M.C., Suarez, M., De la Hoz F. & Hall A.J. 2005. Case-control study of mosquito nets against malaria in the Amazon region of Colombia. American Journal of Tropical Medicine and Hygiene: 73(1); 140-148. Guthmann, J.P., Hall, A.J., Jaffar, S., Palacios, A., Lines, J. & Llanos-Cuentas, A. 2001. Environmental risk factors for clinical malaria: A case-control study in the Grau region of Peru. Transaction of The Royal Society of Tropical Medicine and Hygiene: 95; 577-583. Snow, R.W., Peshu, N., Foster, D., Bomu, G., Mitsanze, E., Ngumbao, E., Chisengwa, R., Schellenberg, J.R., Hayes, R.J., Newbold, C.I. & Marsh, K. 1998. Environmental and entomological risk factors for the development of clinical malaria among children on the Kenyan Coast. Transactions of the Royal Society of Tropical Medicine and Hygiene: 92; 381-385. 25

26. References Binka, F.N., Kubaje, A., Adjuik, M., Williams, L.A., Lengeler, C., Maude, G.H., Armah, G.E., Kajihara, B., Adiamah, J.H. & Smith, P.G. 1996. Impact of permethrin impregnated bednets on child mortality in Kassena-Nankana district, Ghana: A randomized controlled trial. Tropical Medicine and International Health: 1; 147-154. Konradsen, F., Amerasinghe, P., Van der Hoek, W., Amerasinghe, F., Perera, D. & Piyaratne, M. 2003. Strong Association between house characteristics and malaria vectors in Sri Lanka. American Journal of Tropical Medicine and Hygiene: 68(2); 177- 181. Incardona, S., Vong, S., Chiv, L., Lim, P., Nhem, S., Sem, R., Khim, N., Doung, S., Mercereau-Puijalon, O. & Fandeur, T. 2007. Large-scale malaria survey in Cambodia: Novel insights on species distribution and risk factors. Malaria Journal: 6; 37-48. Brooker, S., Clark, S., Njagi, K.J., Polack, S., Mugo, B., Estambale, B., Muchiri, E., Magnussen, P. & Cox, J. 2004. Spatial clustering of malaria and associated risk factors during an epidemic in a highland area of western Kenya. Tropical Medicine and International Health: 9(7); 757-766. Guthmann, J.P., Llanos-Cuentas, A., Palacios, A. & Hall, A.J. 2002. Environmental factors as determinants of malaria risk. A descriptive study on the northern coast of Peru. Tropical Medicine and Health: 7(6); 518-525. Graphpad Software. 2008. McNemar’s test to analyze a matched case-control study. http://www.graphpad.com/quickcalcs/McNemar1.cfm Chang, M.S., Hii, J., Buttner, P. & Mansoor, F. 1997. Changes in abundance and behaviour of vector mosquitoes induced by land use during the development of an oil palm plantation in Sarawak. Transaction of Royal Society of Tropical Medicine and Hygiene: 91; 382-386. Honrado, E.R. & Fungladda, W. 1994. Social and behavioral risk factors related to malaria in Southeast Asian countries. Philippines Journal of Microbiological Infectious Disease: 23(2); 76-80. 26

27. Thank You Thank You 27