Article from The Nation :
" The Department of Medical Sciences' National Institute of Health yesterday revealed that one mosquito can carry two strains of dengue fever, as larvae can be infected with viruses through their mothers.
The NIH also warned that this year's weather changes could lead to an outbreak of the disease.
After receiving an award for outstanding research yesterday for her study of the biology and infection rate of mosquitoes carrying dengue fever, NIH researcher Usavadee Thavara said she conducted the study in 25 dengue-hit provinces from 2006 to 2010 and found that two species of mosquitoes, Aedes aegypti and A albopictus, spread the disease's four strains.
The two species also evolved from usually living at altitudes no higher than 500 metres above sea level to being found at places as high as 1,509 metres at Chiang Rai's Doi Tung area and 1,928 metres at Chiang Mai's Doi Angkhang area. The two species, formerly active only in daytime, now also hunted at night, she said.
While A aegypti's highest biting rate was 45 mosquitoes per person per hour during summer, A albopictus' highest rate was 18 per person per hour in winter, she said."