Mosquito crackdown as Japanese encephalitis cases in Hong Kong reach three-year high

Efforts to eradicate mosquitoes have been stepped up after this year has already seen the highest number of cases of Japanese encephalitis in three years.

The Food and Environmental Hygiene Department launched a 42-day campaign following confirmation of the latest case of the potentially deadly disease a week ago when a 36-year-old British expatriate fell ill.

The man, who lives with his family in Tuen Mun, brought the number of locally acquired cases this year to four - compared to two last year and just one in 2012.

Traps to collect data have been installed at three locations within a two-kilometre radius of the man's home, and the area has been sprayed with mosquito repellant.

Samples from the traps will be sent to the Department of Health for virus analysis.

"We have already cleaned up 46 potential Japanese encephalitis-breeding areas within the two-kilometre radius of the British man's residence," said the head of the department's mosquito risk assessment and advisory unit, Leung Chi-wah.

The Briton's infection came less than three weeks after a 13-year old boy from Tin Shui Wai tested positive for the virus, and about two months after the first case, which involved a 26-year-old woman in the same district.

Unlike previous cases, where there were pig farms near the patients' homes, there are no such farms within the 2km radius of the British man's residence at the Crossroads Foundation, a charity which helps people in need in Hong Kong and around the world.

The infections occurred despite a 42 per cent drop in complaints about mosquito numbers from Tuen Mun residents this year, to 173.