Mosquitos and Dengue Fever

Health

Backgrounder

Can you name two diseases that are carried by mosquitos? Malaria is a common one that most people know. The other disease is called dengue or dengue fever. Sometimes this illness is confused with malaria.

Dengue fever is a virus which is carried from person to person by the bite of a small, dark mosquito. It is a different mosquito than the one that carries malaria. This mosquito is active during the day time, especially early in the morning and in the late afternoon. If you look carefully you will see that this mosquito has white, ring like stripes on its legs.

You get dengue fever if you are bitten by a mosquito that carries it. The disease spreads from person to person this way. It does not spread in any other way.

The dengue mosquito is mostly found in cities and towns. It lives inside houses, in closed in spaces and in dark places. Outside, the mosquito chooses cool and shadowy places. The female mosquitos lay their eggs on the surface of water in containers that contain clean water, for example in tin cans, old tires and flower pots. In general dengue mosquitos only live a few weeks – not more than a month.

The dengue mosquitos attack silently. They bite the lower part of people’s legs, especially around the ankles. They bite in the early hours of the morning and at the end of the afternoon.

If you get dengue fever you will have headaches and pain behind your eyes. You will have a high fever. You will have pain in your joints and muscles. And you may develop a skin rash that begins on your hands and feet and then spreads to your arms, legs and the rest of your body. The rash looks similar to measles.

If you think you have dengue fever you must see a doctor or health worker immediately.

To prevent dengue, control mosquitoes and protect against bites. Cover the baby’s bed with a mosquito netting during the day. Destroy mosquitoes and their larvae. Keep water containers covered. Clean up garbage. Cover pits, old cans, or broken pots that collect water where mosquitos can breed.

Fewer mosquitos mean less dengue!

Acknowledgements

Contributed by: Mr. Mario Zonis, Journalist, National University of Lujan, Argentina.

Reviewed by: Dr. Keystone, Tropical Disease Unit, The Toronto Hospital, Toronto, Canada, and Catherine Fergusson, R.N., Toronto, Canada.

Note
Dengue has two forms: Dengue Fever and Dengue Haemorrhagic Fever. Most dengue infections are not severe and are self limited although the person may feel unwell for several weeks. The initial fever, headache and rash last less than a week. Fatigue and muscle pains may persist and some people become depressed.

Haemorrhagic dengue fever can be quite serious with signs of bleeding and shock. In this case the person should seek medical attention immediately. Dengue haemorrhagic fever is uncommon except in young children, particularly in southeast Asia.