Prevention is the Best Treatment for Mosquito-born Illnesses
Tara A. Spears
It’s official. Jaltemba Bay has medically identified incidences of the viral illness chikungunya. Just following a few preventative steps can make the difference between a fun, memorable vacation trip or picking up a tropical infection. You can blame it on the mosquitoes-those pesky carriers of several viral infections. Unfortunately, the summer/fall seasons with plentiful rainfall creates optimal growing conditions for the mosquito species that transmit chikungunya. 
“The public needs to know the means of transmission, the vectors that spread the illness, the habitat of the mosquitoes, as well as the prevention and management of chikungunya viral illness. Since the first case that I saw among my patients two months ago, I have devoted all the days to give information on the disease through social networks and getting the word out in the community,” explained Dr. Vladimir Munoz Valle, a local family practice physician. He is concerned enough to contact local town officials and health ministers besides holding an informational seminar for the community last week.
Meet the Carriers: Both Ae. aegypti and Ae. albopictus mosquitoes have been implicated in large outbreaks of chikungunya according to World Health Organization data. It is documented that some people naturally repel mosquitoes. As previously reported in Chemistry World, some people naturally repel mosquitoes by giving off a collection of compounds related to the stress response. The pheromones emitted by stressed out individuals deters blood-sucking pests. The research regarding the powerful sense of smell that insects possess is being conducted in labs to try to develop commercial applications.
Aedes aegypti mosquito have evolved a strong preference for humans, making them dangerously efficient vectors of malaria, Dengue haemorrhagic fever, and more recently, chikungunya illness. Specific host odors probably drive this strong preference because other attractive cues, including body heat and exhaled carbon dioxide, are common to all warm-blooded hosts.
The specie Ae. albopictus thrives in a wider range of water-filled breeding sites than Ae. aegypti, including coconut husks, cocoa pods, bamboo stumps, tree holes and rock pools, in addition to artificial containers such as vehicle tires and saucers beneath plant pots. This diversity of habitats explains the abundance of Ae. albopictus in rural as well as urban areas and shady city parks.
Ae. aegypti is more closely associated with human habitation and uses indoor breeding sites, including flower vases, water storage vessels, concrete water tanks, toilets in bathrooms, as well as the same outdoor habitats as Ae. albopictus. With one of the carriers being able to live indoors, it is even more likely that the dreaded virus can be spread.
These mosquitoes can be found biting throughout daylight hours, though there may be peaks of activity in the early morning and late afternoon. Both species are found biting outdoors, but Ae. aegypti will also readily feed indoors.
Symptoms: A high percentage of those infected become sick. It is estimated that 90% of those bitten will develop symptoms.
Symptoms of Chikunguna usually begin three to seven days after being bitten by an infected mosquito and can include fever and severe joint pains, often in the hands and feet, according to the department. Other symptoms can include headache, muscle pain, joint swelling or rash.
People at increased risk for severe disease include newborns exposed during delivery, those 65 or older and people with medical conditions such as high blood pressure, diabetes or heart disease. The mosquito-borne illness was first detected in the Caribbean in December 2013.
The virus is transmitted from human to human by the bites of infected female mosquitoes. Most commonly, the mosquitoes involved are Aedes aegypti and Aedes albopictus, two species which can also transmit other mosquito-borne viruses, including dengue. After the bite of an infected mosquito, onset of illness occurs usually between 4 and 8 days but can range from 2 to 12 days.
People at increased risk for severe disease include newborns exposed during delivery, those 65 or older and people with medical conditions such as high blood pressure, diabetes or heart disease.
The virus is transmitted from human to human by the bites of infected female mosquitoes. Most commonly, the mosquitoes involved are Aedes aegypti and Aedes albopictus, two species which can also transmit other mosquito-borne viruses, including dengue. After the bite of an infected mosquito, onset of illness occurs usually between 4 and 8 days but can range from 2 to 12 days.
Diagnosis and Treatment: Several methods can be used for diagnosis. Serological and viral tests will detect the presence of the chikungunya antibodies. The antibody levels are highest 3 to 5 weeks after the onset of illness and persist for about 2 months.
There is no specific antiviral drug treatment for chikungunya. Treatment is directed primarily at relieving the symptoms, including the joint pain using anti-pyretics, optimal analgesics, and fluids. There is no commercial chikungunya vaccine. “Most people will get better in about a week,” the Center for Disease Control says, although some will need to be hospitalized. A small number of people will have joint pain that lasts for months.
The CDC states that newborns exposed during delivery, people 65 and older, and people with medical conditions like diabetes, high blood pressure, or heart disease are particularly vulnerable to infection and should take extra precautions.
Prevention and control
The proximity of mosquito vector breeding sites to human habitation is a significant risk factor for chikungunya as well as for other diseases that these species transmit. Prevention and control relies heavily on reducing the number of natural and artificial water-filled container habitats that support breeding of the mosquitoes. This requires mobilization of affected communities. During outbreaks, insecticides may be sprayed to kill flying mosquitoes, applied to surfaces in and around containers where the mosquitoes land, and used to treat water in containers to kill the immature larvae.
For protection during outbreaks of chikungunya, clothing which minimizes skin exposure to the day-biting vectors is advised. Repellents can be applied to exposed skin or to clothing in strict accordance with product label instructions. Repellents should contain DEET, IR3535, or icaridin. For those who sleep during the daytime, particularly young children, or sick or older people, insecticide-treated mosquito nets afford good protection. Mosquito coils or other insecticide vaporizers may also reduce indoor biting.
Basic precautions should be taken by people travelling to risk areas and these include use of repellents, wearing long sleeves and pants and ensuring rooms are fitted with screens to prevent mosquitoes from entering.
Prevention and control: The proximity of mosquito vector breeding sites to human habitation is a significant risk factor for chikungunya as well as for other diseases that these species transmit. Prevention and control relies heavily on reducing the number of natural and artificial water-filled container habitats that support breeding of the mosquitoes. This requires mobilization of affected communities. During outbreaks, insecticides may be sprayed to kill flying mosquitoes, applied to surfaces in and around containers where the mosquitoes land, and used to treat water in containers to kill the immature larvae.
For protection during outbreaks of chikungunya, clothing which minimizes skin exposure to the day-biting vectors is advised. Repellents can be applied to exposed skin or to clothing in strict accordance with product label instructions. Repellents should contain DEET, IR3535, or icaridin. For those who sleep during the daytime, particularly young children, or sick or older people, insecticide-treated mosquito nets afford good protection. Mosquito coils or other insecticide vaporizers may also reduce indoor biting.
Basic precautions should be taken by people travelling to risk areas and these include use of repellents, wearing long sleeves and pants and ensuring rooms are fitted with screens to prevent mosquitoes from entering.
“It is the duty of all to stop the disease. Both government and inhabitants have responsibility in containing this illness,” said Dr. Vladimir Munez. But for many of the poor, going to a clinic for diagnosis and treatment is too large a financial burden.”
He also advises that if a member of a household has chikungunya, additional steps should be instigated to contain the spread of the virus. “When chikunguya is already present in a family the household should intensify cleaning of pots and pans, the house should be to fumigated every third day with cypermethrin which is easy to achieve, placing mosquito nets, avoid exposing the family to more mosquitoes in the home through the use of repellent and clothes that protect the extremities from insects. It is highly recommended to take B complex vitamins as a preventative measure.”
Use common sense to enjoy the beautiful Mexican outdoors: slather on insect repellant before taking the evening stroll and sleep with screened windows or a net over your bed. Take a little time to peruse your yard and make sure that there aren’t places with standing water that might attract mosquitoes.
The author wishes to thank Dr. Vladimir for his efforts to keep this illness from becoming an epidemic. For additional information on chikungunya, contact Dr. Vladimir Munez
Calle Venezuela no. 5,
Colonia Juan Escutia (north of central La Penita)
Office tel: 327 107 0456 or cell 322 170 5730
Email: vladimir1977-2008@live.com.mx