1. Health Effect of Climatic Change: Malaysian Senarios
Dr Rozlan Ishak
Environmental Health Unit
Disease Control Division
Ministry of Health Malaysia

2. Situations 50 years ago Malaria was rampant in Malaysia
460,000 cases a year
High mortality and morbidity
Every parts of the country were under malaria
Even the Island of Penang has malaria
Some urban areas were free from malaria

3. Health problems Water supply was inadequate.
Hygiene and sanitation was poor
Latrines were lacking in most parts of the country.
Bucket latrines was the style of the day.
Infectious disease such as cholera, typhoid, dysentery, worms infestation were very common.
Dengue is not a problem!

4. Mosquito borne diseases
50 years later

5. Malaria

6. Dengue Fever

7. Viral Encephalitis

8. Water Borne Diseases
50 years later

9. Cholera

10. Dysentery

11. Food Poisoning

12. Typhoid

13. Hepatitis (all forms)

14. Climate Change Facts !
Global Warming
2100

15. Climate Change

16. Pathways

17. Climate change and health: pathway from driving forces, through exposures to potential health impact.
Source: Climate Change and Human Health – Risks and Reponses. Summary (WHO, 2003)

18. Biological Factors

23. Biologic response to changes in climate
Global warming and wider fluctuation in weather help to spread diseases
Temperatures – affect growth, development and survival of microbes and the vectors
Weather affects the timing and intensity of disease outbreaks (McMichael et al, 2003)

24. Biologic response to changes in climate: Infectious diseases
Warmer environment and mosquitoes
Boost rate of reproduction
Increase the number of blood meal
Prolongs their breeding season
Shorten the maturation period of microbes they carry

25. Heavy downpours
Drive rodents from burrows: risk of zoonotic diseases
Create mosquito breeding sites
Faster fungal growth in houses
Flush pathogens and chemicals into waterways
Milwaukee’s cryptosporidiosis outbreak in 1993
Katrina’s flood 2005: water-borne pathogens and toxins spread.
Johor flood 2007 and leptospirosis

26. Common communicabale diseases sensitive to climate (WHO, 2004)
Climate is the primary factor in epidemic
Cholera, Malaria
Climate plays significant role
Meningococcal meningitis, leishmaniasis, dengue, Japanese encephalitis, Rift valley fever, Ross river virus, St. Louis encephalitis, Murray valley fever

27. Infection & Climate: Potential impact on endemic diseases in Malaysia
Trans-mission
Evidence for inter-annual variability
Climate-epidemic link
Strength of climate sensitivity
Climate-epidemic relationship quantified
Cholera
Food & water-borne
*****
Increase in sea & air temp. Sanitation √
Malaria
Mosquito
Temp. & rainfall. Many others
Dengue
****
Temp., humidity & rainfall
***

28. Temperature, vectorial capacity of Ann
Temperature, vectorial capacity of Ann. maculatus and projected number of malaria cases (Ambu et al. 2003)
Temp (oC)
Esti. Ma
Esti. A
Esti. N C 27 20
0.043 10
0.069 28 21
9.9
0.075 29 22
9.8
0.081 30 25
0.050
9.7
0.096 31
9.6
0.12 32
9.5
0.14 33 35
9.4
0.17 34 40
9.3
0.20

29. Rainfall and dengue outbreak in Malaysia
No. days examined for rain
Low transmission: no. raining days required for an outbreak
High transmission: no. raining days required for an outbreak 30
2.89
0.47 60
4.57
2.15 90
6.25
3.83
120
7.93
5.51
150
9.61
7.19
180
11.29
8.87
210
12.97
10.55
240
14.65
12.33
270
16.33
13.91
300
18.01
15.59
330
19.69
17.27
360
21.37
18.95
Modification of Mogi et al model
Study the threshold of rainfall actually required to trigger an outbreak
Dengue incidence and rainfall data in
Model indicated relatively fewer raining days are required for high transmission
Heavy rain flushes off breeding habitats

30. Potential Health Effects from Global Warming
Year 2100

31. Malaria Year 2100

32. Dengue Fever Year 2100

33. Thank you rozlan@dph.gov.my
What is our plans?
Thank you