There are four types of mosquito-borne flaviviruses that can confer dengue fever and immunity to any type is short-lived so you can actually catch all four types. Each subsequent infection increases in severity with type four being the most virulent.
There are four types of mosquito-borne flaviviruses that can confer dengue fever and immunity to any type is short-lived so you can actually catch all four types. Each subsequent infection increases in severity with type four being the most virulent. Actually about 75 percent of infections are asymptomatic (you don’t feel sick).
With uncomplicated dengue you might feel a headache, fever, muscle aches, eye pain and perhaps a rash. With the severe form, hemorrhagic dengue … you bleed. You may bleed from the nose or mouth, or even your lungs, and it can result in shock and death. The incidence of death from dengue goes from a low of .1 percent to a high of 10 percent of cases. Experts note that it is important to recognize the onset of severe dengue and properly manage the disease process.
Figures from a 2010 estimate shows that Africa and Asia are the two continents where dengue is most rampant. Of the estimated 96 million confirmed cases of dengue 82.5 million were from those two continents. Forty percent of the world’s population lives in areas at risk for dengue fever.
Dengue fever is spread by two mosquito species. The Aedes Aegyptus is a tropical and sub-tropical mosquito that is a very effective vector. It primarily bites people, lives where humans do and bites indoors. The other mosquito is the Asian tiger mosquito — Aedes albopictus — which can live in a more temperate climate, is a less effective vector and bites humans, animals and reptiles. Both species breed in small pools of water (which on Kauai are difficult to control), and both are day-time biters.
Although we have had outbreaks of dengue in the past, the only very large one affecting 30,000 people was in 1903. In 2002 there was an outbreak in the rural areas of Maui, Oahu and Kauai that involved 122 people. In 2011 there was also a small outbreak on Oahu. The current outbreak began on Sept. 15 of this year and as of Friday there are 163 confirmed cases, most of whom are adults.
Prevention is key. The experts advocate improved surveillance, and public education. They want to be sure that cases are correctly attributed to dengue rather than to other viruses or leptospirosis. They also advocate vector control and identification of vector breeding sites. The experts encourage the use of insect repellent, but acknowledge that for many — the homeless and other marginalized people — this may be difficult.
They encourage the use of air conditioning and screens in places of business and residence. They acknowledge that encouraging people to dump out their bromeliads is of little use since the sources of small pools of water on the islands are ubiquitous. Also as the mosquitoes are day biters, bed netting for most people is not required or useful.
The information that I have presented in this article came from a Kauai Medical Reserve Corp seminar presented last week.
The future outlook is that dengue fever is likely to become more of a problem globally, simply because of increased global travel; therefore experts expect future large outbreaks in the sub-tropical parts of the United States.
It is felt that the best protection is personal protection using insect repellents, long-sleeved and long-legged clothing.
Experts warn people to stay away from known mosquito infested areas — especially at dawn and dusk. The Sanofi vaccine is promising some hope of a partial immunity from dengue fever.
If you start to feel unwell after a mosquito bite, get yourself to the doctor. Mosquito control efforts have not stopped outbreaks in other areas but may have potentially prevented some cases. It is basically up to you to fight the bite.
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Jane Riley is a certified nutritional adviser and a certified behavior change specialist. She can be reached at janerileyfitness@gmail.com (808) 212-8119 and www.janerileyfitness.com.
