A WA man has been infected with dengue fever in the Pilbara, the first time the potentially deadly mosquito-borne virus has been contracted in the State in more than 70 years.
The Department of Health confirmed yesterday that a man had contracted the disease recently after being bitten by a mosquito carrying dengue fever at Point Samson, east of Karratha.
A department spokesman said the circumstances of the man's infection were being investigated but it was a concern because there had not been a case of "locally acquired" dengue fever since before World War II.
The spokesman said notifications of dengue fever in WA had risen from 16 in 2006 to 532 last year but all of those had come after people travelled through places such as South-East Asia and Queensland.
Dengue fever is an infectious tropical disease, which comes in several strains that typically cause symptoms including headache, muscle and joint pains and a skin rash similar to measles.
In some cases it can be life-threatening because it leads to a fever involving bleeding and low levels of blood platelets or "dengue shock syndrome", in which the victim's blood pressure falls to dangerously low levels.
"It is most likely that an infected mosquito hitched a ride to the Point Samson area on a ship, in personal belongings of someone returning from overseas, or possibly in a vehicle travelling from north Queensland, and then bit the local person," the spokesman said.
"WA Health is investigating by searching for imported mosquitoes of the type that carry the dengue virus and for evidence of other infected people in the area."
Australian Medical Association WA president Richard Choong said the infection was surprising and alarming given the seriousness of dengue fever.
Dr Choong said the State Government must find out whether there was a population of Pilbara mosquitoes carrying the disease and, if there was, inform people living in and visiting the area.
The department spokesman said there had been no other cases confirmed.
'It is most likely that an infected mosquito hitched a ride to the Point Samson area on a ship.'" A Health Department spokesman