Updated

Central America is on track to have one of its worst years ever for the painful, sometimes fatal disease of dengue, prompting governments across the region to mobilize against the mosquito-borne virus.

There have been 120,000 suspected cases of dengue reported across Central America so far in the season, which is roughly June to November, when the rains make it optimal for mosquito breeding. The number of cases already is about to surpass the total for all of 2012 in the seven countries from Guatemala to Panama. At least 39 people have died so far, more than the 32 for all of 2012.

The disease is endemic to the region, but cases tend to surge every three to five years, and the Pan-American Health Organization says this year's looks unusually bad. Perhaps the worst major outbreak in the Americas was in 2010, when 132 people in Central America died.

Honduras and El Salvador have declared health emergencies to channel extra funds and efforts to prevent the spread of the disease. Other nations are also sending teams of workers across villages and cities to squirt bursts of insecticide at puddles and to lecture citizens against leaving standing water where mosquitoes can breed.

"They're involving people from public health, police and soldiers. It's an all-out effort to fight the effects of the epidemic," said Vilma Areas, spokeswoman for the Nicaraguan Health Ministry.

At least 17 people have died in Honduras, where more than half the municipalities have registered dengue cases.

Most of Nicaragua's 2,000 cases, including six deaths, are concentrated on the border with Honduras, which has reported nearly 18,000 cases so far, compared with 15,000 for all of 2012.

Dengue is a leading cause of illness and death in the tropics and subtropics, according to the U.S. Centers for Disease Control. The virus-transmitting aedes aegypti mosquitoes are found in dense population areas where a combination of people and standing water allow them to breed and thrive.

There is no vaccine or cure for dengue. Treatments can mirror those for standard flu symptoms or can be more extensive for patients who have to be hospitalized. People contracting the most severe type, hemorrhagic dengue, can experience severe pain, breathing difficulties, bleeding and even circulatory failure.

Epidemics can depend on which type of dengue is circulating in a particular year, and whether the population has already built immunities to that type. People with immunity to one type of dengue can still contract others.

"New, susceptible people are being born all the time," CDC epidemiologist Dr. George Han noted.