By Pedro Fonseca
RIO DE JANEIRO, April 8 (Reuters) - Hundreds of Brazilian soldiers swapped ammunition packs for yellow bags of mosquito larvicide on Tuesday, taking the battle against a deadly dengue fever epidemic to the streets of Rio de Janeiro.
The outbreak of the mosquito-borne disease has killed 68 people in the state of Rio, most of them in its capital -- a major tourism destination.
About 60,000 people have contracted the disease since the start of the year. Portugal has confirmed two dengue cases in tourists returning from Brazil this week.
A week ago, the Brazilian military opened three field hospitals in the city to help prevent more deaths from the outbreak that has overwhelmed public clinics. Now troops on anti-dengue foot patrol have joined the military doctors.
"Our motto is ‘strong arm and helping hand’, today it’s about the helping hand," said Lt. Col. Ugo de Negreiros. "It’s a combat soldiers aren’t used to, as they don’t see the enemy."
Some 300 soldiers and officers under his command will visit up to 4,000 dwellings a day during a month, starting with Rio’s impoverished western zone. They will check for pools of stagnant water where dengue mosquito breed and will use powdered chemicals to kill the larvae.
Dengue is a viral disease spread by the small, stripe-bellied Aedes aegypti mosquito and there is no vaccine or drug to cure it. Treatment primarily involves increased fluid intake, administered orally and intravenously.
Dengue can cause high fevers, headaches, muscle and joint pain, lack of appetite and fatigue, but some people can develop the potentially fatal hemorrhagic form of dengue from repeated exposure to more than one strain of the disease.
Biologist and dengue mosquito expert Alvaro Eiras told Reuters that with the epidemic already raging, authorities should concentrate their limited resources on killing mosquitoes that lay eggs and transmit dengue and not larvae that will still take time to become dangerous.
"The city of Rio de Janeiro didn’t do what it was supposed to do, allowing a large mosquito population to form ... During an epidemic, you have to kill the adult mosquito with insecticide," he said.
Authorities have deployed 17 cars equipped with powerful insecticide sprays in the city, but they were fewer than during the last major outbreak in 2002, when many such vehicles were seen circulating in the streets. Dengue killed more than 90 people in Rio state in 2002 and infected 280,000 people.
Authorities hope the outbreak will ease in the coming weeks with the arrival of cooler weather after a hot, wet summer.
Sales of insecticide and anti-mosquito candles have soared. Even foreign tourists arriving in Rio have been seen applying repellent while still at the airport building. (Writing by Andrei Khalip; Editing by Cynthia Osterman)