Relationships between dengue virus infection in mosquitovector, (Aedes aegypti), dengue cases and weatherconditions in Samut Sakhon Province, Thailand
Background : Dengue is commonly found in the tropical and subtropical regions.The disease is still affecting the population of the world especially inSoutheast Asia. The current increase in both morbidity and mortalityrates was associated with the potentiality of the viral transmission.Surveillance focusing on the virus infection in principal dengue vector,weather conditions and number of dengue cases should be evaluatedto develop an effective control approach, therefore reducethe emergence of dengue disease within the endemic and/or new areas.Objectives : To characterize the transmission pattern of dengue virus in the mosquitovector (Aedes aegypti) according to the seasons and to determinethe relationship between dengue virus infections in the mosquito,monthly dengue case reports and weather conditions in a highlyendemic area of Thailand.Research design : Descriptive study.Setting : Ban Phaeo District, Samut Sakhon Province, ThailandMethods : Ae. aegypti mosquitoes were collected from the study site duringthe rainy season of 2012, winter, dry and rainy seasons of 2013.Dengue infection in the mosquitoes was determined by nestedreverse-transcription polymerase chain reaction. The seasonalprevalence pattern of dengue in the mosquitoes was compared tothe dengue cases, and also with to local-weather condition withinthe same periods.Results : Four dengue serotypes were detected in the individual mosquitosamples. The highest rate of infection was shown in the rainy seasonof 2012 (August - November). The infection rate in mosquitoesdeclined in the winter and dry season of 2013. However, the infectionrate in the mosquitoes was increasing in the rainy season of 2013.The trend of the dengue cycle in mosquito vector likely associatedwith that from the cycle of dengue cases or the morbidity rate inthe study area. Interestingly, those were also associated withthe changes of local weather conditions, i.e. temperature and relativehumidity.Conclusions : The result showed significant association between the pattern ofdengue case, morbidity and the dengue infection in the mosquitovectors. Incidence trends of the disease were also accompanied withthe consecutive data of both humidity and temperature. Therefore,the data could improve the surveillance and contribute to betterprediction of the magnitude for the dengue outbreak.
Faculty of Medicine, Chulalongkorn University
Kittichai, Veerayuth; Montriwat, Prakaikaew; Chompoosri, Jakkrawarn; Bhakdeenuan, Payu; Pengsakul, Theerakamol; Tawatsin, Apiwat; Thavara, Usavadee; and Siriyasatien, Padet
"Relationships between dengue virus infection in mosquitovector, (Aedes aegypti), dengue cases and weatherconditions in Samut Sakhon Province, Thailand,"
Chulalongkorn Medical Journal: Vol. 59:
4, Article 2.
Available at: https://digital.car.chula.ac.th/clmjournal/vol59/iss4/2