It’s that time of year again: green season. With daily rains come swarms of mosquitoes – many carrying the dreaded virus dengue fever.
Imagine the worst flu you’ve ever had, and then magnify it by 10. Add crippling headaches, high fevers, joint and muscle pain and a skin rash, and you’ve got dengue fever. The most intense symptoms usually last 7-10 days, but it can take months for the body to fully recover.
There are four different types of dengue fever infection, and all lower blood platelet counts. But one strain, dengue hemorrhagic fever, can actually be fatal if untreated. The sole remedy for dengue fever is to wait it out, keep hydrated and control fever with Tylenol.
Because there is no vaccine for the virus, the only surefire way of avoiding it is prevention. Not much research exists on the virus or its carrier, the Aedes aegypti mosquito. What scientists do know is that dengue-carrying bloodsuckers have black and white coloring and usually bite during the day rather than the night. Dengue-carrying mosquitoes also prefer shady, lowland areas, and they hide in holes and recesses that collect any amount of fresh, stagnant water. This includes holes in the ground, underneath flowerpots, and manmade receptacles like old car tires, buckets, leaky faucets and wheelbarrows.
According to National Coordinator of Disease Control Rodrigo Marín, Aedes aegypti larvae are extremely resilient. Not wanting to submerge themselves in liquid, mosquitoes lay eggs in dry places that are likely to eventually fill with water. Larvae can survive up to one year without being activated by water.
Last year, residents of the northwestern Pacific beach town Tamarindo began noticing an alarming increase in dengue incidents around the middle of the rainy season. Local resident Shlomy Koren, owner of Seasons restaurant, decided to do something about it for the sake of his family.
“My wife had dengue four years ago and she almost died because of complications in the hospital,” he said.
Koren organized a town cleanup. He hired a private crew of 10 men to collect trash for two days, which cost roughly $1,000. Next, he contacted the Health Ministry and asked health officials to come spray the town. But they asked him to show statistics proving that the number of dengue cases was increasing – statistics he didn’t have.
“It’s a tricky virus to diagnose because you can only do a blood test two days after you are feeling bad. Then you have to keep being tested,” said Koren. “A lot of people just ride it out at home and never get checked, so the numbers are off.”
According to Hanzel Larios, a physician in Playas del Coco, in the northwestern Guanacaste province, some dengue cases go undocumented because they aren’t officially diagnosed.
“There is only one definitive diagnostic test that costs ₡17,000 [$34],” Larios said. Although the test is covered by the Social Security System (Caja), many people don’t go to the doctor. A cheaper test called a blood panel is also available, but only results from the official test are reported to the Health Ministry database.
In an effort last year to raise money for dengue awareness, Koren started a fundraising campaign. He emailed Tamarindo residents and business owners and asked for donations. “It ended up being a big joint operation,” he said. “Everything we did was because of the Ministry of Health and the support of Dr. Marín.”
Marín said that while a town cleanup is a good idea, it isn’t the best method of attack when it comes to dengue prevention. “Fumigation is not the solution. The solution is eliminating the deposits of water where the mosquitoes reproduce,” he said. Up to 90 percent of all carriers are bred within residential homes, he added.
As an extra precaution, Marín agreed to fumigate Tamarindo if the community would pay for food and lodging for 10 ministry employees, as well as gas and diesel to operate the fumigators – roughly $400 per fumigation.
Marín also laid out a plan to educate the town about how to eliminate mosquito breeding grounds. Local hotels like Capitan Suizo and Hotel Barcelo pitched in and donated food.
“These guys went house to house,” said Koren. “They had a piece of chalk, so if someone wasn’t home they’d mark the house to know that they had to come back. Volunteers helped out… They checked in the backyard of everyone’s home [and] went into the gutters with mirrors to look for larva.”
In one case, Health Ministry officials found that 200 new plants at a hotel development were hosting mosquito larva.
“It’s very important to get a professional out there,” said Koren. “I would go to places that looked OK to me, but when [the ministry] checked with mirrors I was astonished at what they could find.”
Marín is enthusiastic about squelching the spread of dengue fever in Costa Rica. He recently spoke in Flamingo, in Guanacaste, and will be giving a speech on prevention in Playas del Coco on June 23.