Q. What is dengue?
A. Dengue (pronounced den' gee) is a disease caused by any one
of four closely related viruses (DEN-1, DEN-2, DEN-3, or DEN-4). The viruses
are transmitted to humans by the bite of an infected mosquito(Aedes aegypti).
The Aedes aegypti mosquito is the vector of dengue/DHF. It is estimated
that there are over 100 million cases of Dengue worldwide each year.
Q. What is dengue hemorrhagic fever
A. DHF is a more severe form of dengue. It can be fatal if
unrecognized and not properly treated. DHF is caused by infection with the same
viruses that cause dengue. With proper management, mortality due to DHF can be
Q. How are dengue and dengue hemorrhagic
fever (DHF) spread?
A. Dengue is transmitted to people by the bite of an Aedes
mosquito that is infected with a dengue virus. The mosquito becomes infected
with dengue virus when it bites a person who has dengue or DHF and after about
a week can transmit the virus while biting a healthy person. Dengue cannot be
spread directly from person to person.
Q. What are the symptoms of the disease?
A. The principal symptoms of dengue are high fever, severe
headache, backache, joint pains, nausea and vomiting, eye pain, and rash.
Generally, younger children are more affected than older children and adults.
Dengue hemorrhagic fever is
characterized by a fever that lasts from 2 to 7 days, with general signs and
symptoms that could occur with many other illnesses (e.g., nausea, vomiting,
abdominal pain, and headache). This stage is followed by hemorrhagic
manifestations, tendency to bruise easily or other types of skin hemorrhages,
bleeding nose or gums, and possibly internal bleeding. The smallest blood
vessels (capillaries) become excessively permeable (“leaky”), allowing the
fluid component to escape from the blood vessels. This may lead to failure of
the circulatory system and shock, followed by death, if circulatory failure is
Q. What is the treatment for dengue?
A. There is no specific medication for treatment of a dengue
infection. Persons who think they have dengue should use analgesics (pain
relievers) with paracetamal and avoid those containing aspirin. They should
also rest, drink plenty of fluids, and consult a physician
Q. Is there an effective treatment for
dengue hemorrhagic fever (DHF)?
A. As with dengue, there is no specific medication for DHF. It
can however be effectively treated by fluid replacement therapy if an early
clinical diagnosis is made. Hospitalization is frequently required in order to
adequately manage DHF.
Q. Where can outbreaks of dengue occur?
A. Outbreaks of dengue occur primarily in areas where Aedes
aegypti (sometimes also Aedes albopictus) mosquitoes are found in
large numbers. This includes urban areas as well as rural areas. Dengue viruses
may be introduced into areas by migratory workers who become infected while
visiting other endemic areas, where dengue commonly exists.
Q. What can be done
to reduce the risk of acquiring dengue?
A. There is no vaccine for preventing dengue. The best
preventive measure for residents living in areas infested with Aedes aegypti
is to eliminate the places where the mosquito lays her eggs, primarily
artificial containers that hold water.
Items that collect
rainwater or are used to store water (for example, plastic containers, drums,
buckets, or used automobile tires) should be covered or properly discarded. Pet
and animal watering containers and vases with fresh flowers should be emptied
and scrub dried at least once a week. This will eliminate the mosquito eggs and
larvae and reduce the number of mosquitoes present in these areas.
For travellers to
areas with dengue, as well as people living in areas with dengue, the risk of
being bitten by mosquitoes indoors is reduced by windows and doors that are
screened. Proper application of mosquito repellents on exposed skin and use of
full sleeve clothes decreases the risk of being bitten by mosquitoes.
Q. How can we
prevent epidemics of dengue hemorrhagic fever (DHF)?
A. The emphasis for dengue prevention is on sustainable,
community-based, integrated mosquito control, with limited reliance on
insecticides (chemical larvicides and adulticides). Preventing epidemic disease
requires a coordinated community effort to increase awareness about how to
control the mosquito that transmits it. Residents should be made responsible
for keeping houses and surroundings free from mosquito breeding by emptying
& scrub drying the rotate containers once a week
Tamil Nadu Scenario