State health officials confirmed Friday that they are spraying areas of Kaua’i in an attempt to knock out dengue fever at its source: Ponds and standing water where mosquitos breed.
“We are spraying in areas where there are suspected cases of dengue fever,” including Anahola, Kalaheo and Poipu, said Jo Manea, an epidemiology specialist with the Department of Health office on Kaua’i.
Manea said the spray is a non-DDT-based product.
She added that people who want to spray around their homes, but are afraid of toxic chemicals, can use many safe (for humans) repellents sold at homecare and garden stores.
Manea said dengue fever cases are highly suspected, after field testing, in Anahola and Kalaheo, but that none of the cases have been officially confirmed by the Centers for Disease Control (CDC) in Atlanta, Ga.
There are 21 confirmed cases in east Maui, with another 100 suspected on that island.
Blood tests and clinical testing are used to officially pinpoint a case.
Dengue fever is transmitted by the Albopictus mosquito. There are four strains of the disease, and exposure to one doesn’t grant immunity to the other three. That means it is possible, according to medical experts, to catch dengue fever four times in a lifetime.
Symptoms, which appear in 20 to 30 percent of all cases, include headaches, chills and fever.
The Albopictus is a daytime mosquito. Experts advise wearing long-sleeve clothing and using mosquito repellent on skin and clothing.
The myth is that the offending mosquitos can only live for two to three days. But Roland Mortimer, a Brazilian dengue fever expert, reported that if unmolested, the Albopictus can live for months.
The males of the species do not bite. Dengue fever is transmitted solely by the females, according to Mortimer.
Kaua’i and Maui are not suffering from dengue fever alone. The CDC reports “a global pandemic” of dengue fever, which began in Southeast Asia after World War II, and has intensified during the past 15 years.
Hawai’i is not the only place where the disease reasurfaced after disappearing for two to three decades. After an absence of 30 to 35 years, it reappeared in the People’s Republic of China and Taiwan in the mid-1980s.
Singapore implemented a successful dengue fever control program in the early 1970s, but had a resurgence of the disease between 1990 and 1994, anyway.
And in 1994, Pakistan reported its first-ever dengue fever epidemic.
On the U.S. mainland, the only indigenous outbreaks in the past 20 years took place in south Texas, although more than 2,000 people have returned from Asia and the tropics with dengue fever. The last outbreak in Texas was in 1996, killing at least one person.
The CDC said dengue fever returned to the Pacific in the early 1970s after an absence of 25 years. The last serious outbreak in Hawai’i was in 1943. Those known to be infected numbered 1,420; three people died.
Most at-risk, according to health officials, are young children and the elderly.
Bill Woods, a former state health department administrator now living on Oahu, noted that the disease can reappear, even after spraying mosquitos.
“I was in Fiji this February and they had had no cases for seven or eight months, and then it reappeared,” Woods said. He added that the disease may spread within the mosquito population and via animals, other than humans, for as long as a year.
Until World War II, there were always long intervals of 10 to 40 years between tropical dengue epidemics because, according to CDC officials, the viruses and their mosquito vectors could only be transported between population centers by boat.
According to the CDC, the reasons for the dramatic global upswing in dengue fever are the result of several factors:
– First, effective mosquito control is virtually non-existent.
– Second, major global demographic changes have occurred, the most important of which have been uncontrolled urbanization and concurrent population growth resulting in inadequate water, sewer and waste management system.
– Third, increased travel by airplanes provides the ideal mechanism for transmitting viruses between population centers in the tropics.
– Lastly, in most countries the public health infrastructure has deteriorated.
Despite claims that there are cures for dengue fever, the CDC is not optimistic.
Vaccines reportedly are being developed in Thailand. But CDC officials say the vaccines haven’t been tested on humans, putting an effective public vaccine at least five to 10 years in the future.
Staff writer Dennis Wilken can be reached at 245-3681 (ext. 252) and mailto:dwilken@pulitzer.net
