Mosquitoes are the main carriers of insect-borne illnesses common throughout tropical areas around the world. The best approach to avoiding malaria and other mosquito-borne illnesses is to avoid being bitten by mosquitoes in the first place. Mosquitoes are most abundant during the rainy season, so take special care to protect against mosquito bites during this time of year. Some travelers favor liberal application of bug spray with DEET as the active ingredient, which seems to be the most effective at keeping the critters at bay. Plant-based bug sprays seem to be less effective. It’s also possible to buy clothing treated with permethrin, a bug-repellent chemical. It’s also possible to buy it separately and treat your clothing with it. Treated garments are scentless in addition to being highly insect repellent. You can find these products in camping and outdoor stores.
Malaria is transmitted by the female Anopheles mosquito and is prevalent in the Caribbean lowlands and Petén jungles, though not in the highlands. Anopheles mosquitoes tend to bite at night. Flulike symptoms of malaria include high fever, chills, headaches, muscle pain, and fatigue. It can be fatal if left untreated.
Some travelers also opt to take antimalarial drugs, available locally without a prescription (and quite cheaply). The most widely used is chloroquine, known by its brand name Aralen. Although chloroquine-resistant strains of malaria are found in other parts of the world, including South America, this is not the case in Guatemala. You’ll need to start taking the drug (500 mg) a week before arriving in malarial zones, weekly while there, and continue to take it once a week for at least four weeks after you’ve left the malarial zone. Other travelers opt to take two 500 mg doses with them to use if and only if the disease strikes.
Some people experience marked side effects while taking chloroquine, including nausea, headaches, fever, rashes, and nightmares. A newer antimalarial drug, malarone, was approved by the FDA in 2000, supposedly with fewer side effects than traditional drugs and which does not need to be taken for as long. It is not yet widely available in Guatemala.
Dengue is also transmitted by mosquitoes and is prevalent in lowland areas, though it is far less common than malaria and only rarely fatal. Although there is no treatment, most people recover from its debilitating symptoms, which include a fever that can last 5–7 days, headache, severe joint pain, and skin rashes. The disease may last up to another week after the fever has lifted. Tylenol can help reduce the fever and counteract the headaches. Dengue is transmitted by a mosquito that bites during the daytime, the Aëdes aegypti. A far less common, though potentially fatal, form of dengue is hemorrhagic dengue. It needs to be treated within a few days of the appearance of symptoms, which are a carbon copy of regular dengue symptoms until severe hemorrhaging sets in, making medical treatment well advised at the first sign of dengue.
Spread by the bites of the conenose and assassin bugs living in adobe structures and feeding at night, Chagas’ disease is most common in Brazil but also affects millions of people between Mexico and Argentina. Curiously, Panama and Costa Rica are Chagas-free, probably because of the absence in local construction styles of adobe structures. Chickens, dogs, and rodents are thought to carry the disease. Avoid sleeping near the walls of an adobe structure and wear DEET-containing bug spray to bed. The only time this may be a consideration for the average traveler is if trekking across areas of the Western Highlands and staying with local families, who tend to live in adobe structures. Chagas-carrying bugs also tend to be found in dried palm leaves, which makes mosquito netting a must for the traveler sleeping under thatched-roof structures that are not insulated by wire mesh.
The disease usually starts off as a swollen bite accompanied by fever, which eventually subsides. Chagas’ disease may eventually cause heart damage leading to sudden death and there is no cure for this disease. Only about 2 percent of those bitten ever develop Chagas’ disease.