Presenter: Pattamaporn Kittayapong, Ph.D. Mahidol University, Thailand

Transcription

1 Study on Potential Impacts and Proposed Best Practices in Agricultural Development: A Case Study of Rubber Plantation Expansion and Increased Risk of Vector-Borne Diseases in Eastern Thailand Presenter: Pattamaporn Kittayapong, Ph.D. Mahidol University, Thailand

2 TOPIC OUTLINE Phase I: Baseline Situation Analysis and Eco-Bio-Social Data Collection Phase II: Health Education and Community/Public Engagement Phase III: Intervention Using DEET- Impregnated Jackets and Super- Sterile Male Mosquitoes

3 Research Partners 1. Mahidol University Dr. Pattamaporn Kittayapong, Faculty of Science Dr. Worachart Sirawaraporn, Faculty of Science Dr. Luechai Sringernyuang, Faculty of Social Science and Humanities Ms. Suwannapa Ninphanomchai Ms. Supaluk Khaklang 2. Kasetsart University Dr. Suporn Thongyuan, Faculty of Veterinary Medicine 3. Ministry of Public Health Dr. Chitti Chansang, Department of Medical Sciences Dr. Uruyakorn Chansang, Department of Medical Sciences 4. Rajabhat Rajanakarindra University, Chachoengsao Dr. Pongsri Maskhao, Former Dean, Faculty of Humanities and Social Science

4 Research Objectives 1. To determine whether the expansion of rubber plantation in eastern Thailand increases the risk for vector-borne diseases using chikungunya, dengue and malaria as proxy diseases 2. To investigate whether there are solutions and best practices in rubber plantation that could reduce the risk for these vector-borne diseases 3. To investigate whether behavior and livelihood of rubber workers could be changed to reduce vulnerability to vectorborne diseases

5 Dengue Situation in Thailand BANGKOK - After a year which saw an explosion of dengue fever infections, Thailand is bracing itself for an even worse 2016 with experts warning the number of infections may be on par with the 1987 mega-outbreak. Thailand recorded some 140,000 cases of infection in 2015, the highest number since the 170,000 cases of the 1987 crisis. (Chiangrai Times, 28 th January 2016) 2015 Total cases 144,952 Morbidity rate Mortality rate 0.23

6 Zika Disease Situation in Thailand Thailand has most Zika cases in region Thailand is the worst-hit country in South-east Asia, with seven Zika cases uncovered between 2012 and 2014 in various provinces. The Philippines, Cambodia, Indonesia and Malaysia each have had one Zika-related case since But World Health Organisation (WHO) officials say the disease is likely to have spread far more widely in South-east Asia than the number of cases suggests. (StraitsTimes, 30 th January 2016)

7 Research Strategic Sites Rubber plantation areas in Thailand (left) in 2011 and in Chachoengsao Province (right) in

8 Increased Risk of Dengue in Rubber Plantations Dengue cases in the districts with (left) and without (right) rubber plantations in Chachoengsao Province, eastern Thailand.

9 Increased Risk of Chikungunya in Rubber Plantations Rubber areas and Chikungunya cases per 1000 people in four sub districts in Wang Chan District.

10 Increased Risk of Dengue and Chikungunya in Rubber Plantations Chikungunya cases in each villages in Wang Chan District with Thaichote Satellite images.

11 (N = 503) Working time scale in rubber plantation, Chachoengsao Province, Thailand.

12 High Risk for Mosquito-Borne Diseases in Rubber Workers Living and working Tapping Rubber sheet making Activities in rubber plantations An. dirus Ae. albopictus Ae. aegypti Ae. aegypti An. minimus An. maculatus Ae. albopictus An. dirus Time scale Feeding time of mosquito vectors Dawn All day (stay in rubber plantations) Evening Period of time that migrants enter rubber plantations Working hour and associated mosquito vectors in rubber plantations

13 Sample Collection in Rubber Plantations Household Rubber plantation Mosquito Vectors Domestic dogs Water Soil Immature Adults Virus : CHICK DENV Heavy metal Pesticide Quality Contamination Biological Heavy metal Herbicide Contamination Microbial Heavy metal Herbicide

14 Mosquito Vectors Transmitting Dengue,Chikungunya, Zika and Yellow Fever Aedes aegypti Major vector: chikungunya, dengue, yellow fever and Zika viruses Main habitats: Households (indoor) Aedes albopictus Minor vector: chikungunya, dengue, yellow fever and Zika viruses Main habitats: Gardens, rubber plantations and forest areas (outdoor)

15 Mosquito Sample Collection in Rubber Plantations 109 of 156 houses with rubber plantation were visited

16 Mosquito Sample Collection in Rubber Plantations Adult mosquito collection by using vacuum aspirator

17 Number of Collected Adult Mosquitoes by Species and Collection Places Collection places Mosquito species Indoor House Outdoor Rubber plantation M F Total M F Total M F Total Ae. aegypti Ae. albopictus Culex spp Armigeres spp

18 Blood Collection in Domestic Dogs Visited houses No of blood sample collection No of PCR +ve DENV No of PCR +ve CHIKV

19 Heavy metal No. of samples Range (µg/dl) Mean ± SD No. of sample above limit value(%) Lead ±1.2 0 Cadmium ±0.2 18(54.5) Manganese ±1.8 33(100) Nickel ±0.3 10(76.9) Results: Blood samples from domestic dogs found high concentration level of manganese (100%), nickel (76.9%) and cadmium (54.5%).

20 Ground water in households Water Quality Assessment in Rubber Plantation Areas Natural water reservoirs Waste water reservoirs

21 Water Quality and Contamination Type of water Ground water Natural source Watse water Water usage drink drink+ domestic domestic use Total domestic use Not use Lab Results N=3 N=17 N=32 N=52 N=23 N=7 Chloride (<250 ppm) NA Iron (<0.3 ppm) 0 0 6(18.75%) 6(11.54%) 14(60.87%) NA Copper (<1.0 ppm) NA Manganese (<0.05 ppm) 1(33.33%) 1(5.88%) 4(12.5%) 6(11.54%) 0 NA Zinc (5 ppm) NA Calcium (<100 ppm) NA Magnesium (<50 ppm) 0 2(11.76%) 0 2(3.85%) 0 NA Cyanide (<0.2 ppm) NA Sulfate (250 ppm) NA Nitrate (10 ppm) 0 1(5.88%) 0 1(3.13%) 0 NA Ammonia (<0.2 mg/l) 0 0 7(21.88%) 7(13.46%) 13(56.52%) NA Total Dissolved Solid (500 ppm) (100%) BOD (<30 ppm) NA NA NA NA NA 7(100%) COD (<120 ppm) NA NA NA NA NA 7(100%) Total bacteria count (<500cfu/mL) 3(100%) 17(100%) 12(37.5%) 32(61.54%) 22(95.65%) 7(100%) Coliform ( cfu/ml) 3(100%) 17(100%) 18(56.25%) 39(75%) 16(69.57%) 7(100%) E. coli (0 cfu/ml) 3(100%) 6(35.29%) 4(12.5%) 15(28.85%) 2(8.70%) 6(85.71%) Salmonella spp. (positive/negative) 0 1(5.88%) Gr.E 0 1(1.92%) 1(4.35%) Gr. E 0

22 Water Quality: Parameters that are over standard values Ground water (N=52) Natural source water(n=23) Waste water (N=7) Iron 6(11.5%) Iron 14(60.87%) Manganese 6(11.5%) Magnesium 2(3.85%) Nitrate 1(3.13%) Ammonia 7(13.46%) Ammonia 13(56.52%) Bacteria *E. Coli 15(28.85%) *Salmonella Gr E 1(1.92%) Bacteria *E. Coli 2(8.7%) *Salmonella Gr E1(4.35%) Total Dissolved Solid (TDS) 7(100%) Bacteria *E. Coli 6(87.5%)

23 Quality Indicators and Residue of Soil Samples Indicators Limit value No of sample (%) Total bacteria count >50000 cfu/ml 107(100%) Coliform bacteria >1000 cfu/ml 104(97.2%) E.coli >1000 cfu/ml 27(25.23%) Salmonella spp. Found (Gr E) 1(0.93%)

24 Percentage Environmental Contamination in Rubber Plantations 120 Iron Manganese Magnesium Nitrate Ammonia E. Coli Salmonella Ground water Natural source water Waste water Source of water samples

25 Inappropriate Handling of Chemicals in Rubber Plantations

26 Community Engagement and Health Education

27 Public Engagement Through Media

28 Public Engagement Through Media

29 Intervention Using DEET-Impregnated Screen Jackets The research was conducted in collaboration with NanoTec, MOST, Thailand

30 Mean Intervention Using DEET-Impregnated Screen Jackets 25 Mean Number of Mosquitoes Collected after Volunteers being Exposed to DEET-Impregnated Jackets during Day & Night Time in Rubber Plantations Control Treatment Day_(In+Out) Night_(In+Out) Period of Collection There is statistically significant difference in the number of mosquitoes collected when compared between day and night (F=4.904, P=0.027). When compare between treatment and control, there is statistically significant difference both during the day (F=34.280, P=0.000) and during the night (F=25.565, P=0.000) (Kittayapong et al. unpublished data)

31 Mean Intervention Using DEET-Impregnated Screen Jackets 25 Mean Number of Mosquitoes Collected after Volunteers being Exposed to DEET-Impregnated Jackets before (In) and after (Out) Working in Rubber Plantations Control Treatment In_(Day&Night) Out_(Day&Night) Period of Collection -5 There is no statistically significant difference in the number of mosquitoes when compared between collection time before (in) and after (out) working (F=0.227, P=0.634) but when compared between treatment and control, there is statistically significant difference both before working (In) (F=25.842, P=0.000) and also after working (Out) (F=34.037, P=0.000) (Kittayapong et al., unpublished data)

32 Intervention Using Super-Sterile Male Mosquitoes The research was conducted in collaboration with MOPH and MOST, Thailand

33 Intervention Using Super-Sterile Male Mosquitoes

34 Intervention Using Super-Sterile Male Mosquitoes Periphery Center

35 Total eggs(eggs) Rainfall (mm) Total eggs(eggs) Rainfall (mm) Intervention Using Super-Sterile Male Mosquitoes Average Eggs & Hatched Eggs in the Center of Village 11, Plaeng Yao District, Chachoengsao Province Total Eggs Total Hatched Eggs Rainfall Rainy Season Winter Summer Precipitation Rainy Season Collection time Release super-sterile male mosquitoes 3500 Average Eggs & Hatched Eggs in the Periphery of Village 11, Plaeng Yao District, Chachoengsao Province Total Eggs Total Hatched Eggs Rainfall Precipitation Collection time Release super-sterile male mosquitoes 0

36 Percetage Rainfall (mm) Intervention Using Super-Sterile Male Mosquitoes Mean Egg Hatch in the Center and Periphery of Village 11, Plaeng Yao District, Chachoengsao Province Center Periphery Control Rainfall Rainy Season Winter Summer Rainy Season Precipitation Control Collection time 0 Release Super-Sterile male mosquitoes

37 Conclusions - Community engagement and health education could raise awareness on environmental contamination and risk of vector-borne diseases among rubber workers - DEET-impregnated jackets could reduce mosquito bites - Super-sterile male mosquitoes could induce infertility in natural mosquito vectors which should then lead to the reduction in vector populations and eventually the diseases they transmit.

38 Acknowledgement This research work received financial support from International Development Research Centre (IDRC) through the Field Building Leadership Initiative (FBLI).