Kaohsiung takes dramatic step to fight dengue fever

Kaohsiung, Nov. 10 (CNA) Desperate to exterminate mosquitoes spreading the dengue virus, the Kaohsiung Department of Health on Monday flooded drainage systems in two dengue fever-affected wards with sea water, hoping it will kill the insects. Health department technical specialist Chen Chao-tung said the water was brought in from the city's coastal areas of Cijin, Cianjhen, Gushan and Sizihwan, which had average salinity of over 30 practical salinity units (PSU). "Mosquito larvae soaked in such sea water for 12 hours will die," Chen said, touting the "sea water treatment" as efficient in killing vector mosquitoes. The official said the sea water in the drainage system will eventually flow into the sea and will not cause any pollution, Chen said. Asked whether this alternative strategy to wipe out vector mosquitoes will damage the ecology, Chen said using pesticides would generate more destructive toxicity than sea water. If the strategy proves effective, it will be carried out on a wider scale, the specialist said. On Monday, only two wards in Sanmin District, which has one of the largest dengue fever outbreaks in the southern municipality, were given the alternative treatment. The city health department said there had been 10,012 indigenous dengue fever cases this year in Kaohsiung as of Nov. 9, including 11 deaths. The Centers for Disease Control put the number of deaths at only nine as of Nov. 9, and said the total number of cases at 10,516 in all of Taiwan, far higher than the 860 cases that occurred in Taiwan all of last year. Commenting on the unconventional measure to eliminate vector mosquito larvae, mosquito expert Lien Jih-ching called it "unbelievable," saying he worried the strategy would achieve nothing but waste time and money, a local newspaper reported on Monday. Lien, known in Taiwan as "Mosquito Man" or "Doctor Mosquito," said the main species of vector mosquito that spreads dengue fever is the yellow fever mosquito, which likes clean water and rarely stays in drainage systems. The insect mostly breeds in containers or basements with stagnant water, said Lien, who suggested that the best way to wipe out vector mosquitoes was to empty water from flowerpots and buckets and keep basements dry. Dengue fever is an influenza-like viral disease spread by the bite of infected mosquitoes. The disease is characterized by such symptoms as high fever, rash, severe headache, pain behind the eyes, and muscle and joint pain. The severe type of the infection, dengue hemorrhagic fever, is fatal. (By Cheng Chi-fong and Elizabeth Hsu)