1. Royal Thai Army
Roles of mosquito vectors, bats, and swine in the epidemiology of emerging and re-emerging infectious diseases
Akina Sukasem, 2LT Kanokporn Kanthavichit,
Korakot Chairatnikorn, Pichaya Phataisit,
Sonthaya Tiawsirisup

2. BACKGROUND Emerging and re-emerging diseases
- The most important of global significance
Mostly zoonosis
At least 66 species of virus were found in bats
Bats become an important reservoir
Mosquitoes are an important vector in both human and animal infection

3. Emerging and re-emerging virus
Japanese encephalitis virus (JEV)
West Nile virus
(WNV)
Nipah virus
Dengue virus
Chikungunya virus
english.ytpo.net
Visuals Unlimited, Inc./Scientifica/C. S. Goldsmith, P. E. Rollin
rationaldiscoveryblog.com/post/ /dengue-virus
fineartamerica.com/products/2-chikungunya-virus-capsid-science-photo-library-poster.html

4. Japanese Encephalitis Virus (JEV)
Important cause of encephalitis in humans
Esp. under 15 years of age
Culex plays important role as a vector
The outbreak mostly occurs in rainy season
There are more than 30,000 cases reported in Asia (Lobigs, 2012)
In Thailand; from 101 cases in 2011 to 144 cases in 2014 (Tipsriraj, 2015)

5. Japanese Encephalitis Virus Transmission Cycle
Amplifying host
Japanese Encephalitis Virus Transmission Cycle
Dead end host because they produce low viraemia levels over a limited timeframe that are insufficient to infect feeding mosquitoes
Dead-end host

6. Distribution of Japanese Encephalitis Virus

7. West Nile Virus (WNV) WNV was first isolated in Uganda in 1937
WNV can be found worldwide, especially in Africa continent
West Nile virus can cause a fatal neurological disease in humans
Human and horse are dead-end host and Culex play important role as a vector

8. West Nile Virus Transmission Cycle

9. Distribution of West Nile Virus
Gubler D J Clin Infect Dis. 2007;45:

10. The purposes of this project
To study the roles of mosquito as a vector in virus transmission cycle from bat to swine in Panatnikom, Chonburi
To study the amount and species of mosquito found in Panatnikom, Chonburi
To detect JEV and WNV in mosquito for surveillance and control the emerging and re-emerging diseases

11. Mosquitoes counting and identification Viral RNA detection by RT-PCR
Material and method
Sample collection
Mosquitoes counting and identification
Viral RNA Extraction
Viral RNA detection by RT-PCR

12. Sample collection Sample collection date: from
Using CDC-light trap with dry ice (source of CO2)
Place the trap on the tree overnight and collect it in the morning
Sample collection date: from
August 2011
to October 2012

13. Map of Chonburi
Blue : Pig farm Red : Bat habitat

14. Mosquitoes counting and identification Viral RNA detection by RT-PCR
Material and method
Sample collection
Mosquitoes counting and identification
Viral RNA Extraction
Viral RNA detection by RT-PCR

15. Mosquitoes identification
Culex
Mansonia
Armigeres
Anopheles
Aedes
Courtesy of Dr. Sonthaya Tiawsirisup

16. Mosquitoes counting and identification Viral RNA detection by RT-PCR
Material and method
Sample collection
Mosquitoes counting and identification
Viral RNA Extraction
Viral RNA detection by RT-PCR

17. Mosquitoes counting and identification Viral RNA detection by RT-PCR
Material and method
Sample collection
Mosquitoes counting and identification
Viral RNA Extraction
Viral RNA detection by RT-PCR

18. Result The dominant species of the collected mosquitoes
Culex tritaeniorrhynchus : 65.40%
Culex gelidus : 27.14%
Mansonia uniformis : 4.03%
The mosquitoes abundant were high in
August 2011, October and July 2012
The mosquitoes abundant were low in
January and April 2012

19. Chart shows the amount of mosquitoes in each month of sample collection
1 : Bat habitat
2 : Pig farm

20. Flavivirus NOT found RT-PCR RESULTS Sample Ladder Negative Positive 12
203 bp 
Flavivirus NOT found

21. Conclusion and discussion
Result were negative because of
This area may not be the risk area for Flavivirus or virus is to less to detect
Low level of virus antigen titer as same as the study of West Nile Virus in Aedes. No antigen titer was found after mosquitoes fed on chicken blood with WNV titer < PFU/ml (Tiawsirisup, 2008)
Duration of viremia is only ten days (Leake et al., 1986)

22. Conclusion and discussion
Further study
Surveillance in other mosquitoes population
Detection of antigen or/and immune response in pigs
Detection of antigen or/and immune response in bats

23. Acknowledgements
Parasitology Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University.
Center of Excellence Emerging and Re-emerging Infectious Diseases in Animals, Faculty of Veterinary Science, Chulalongkorn University.
Faculty of Medicine, Chulalongkorn University.

24. QUESTION??

25. Thank you for your attention