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Measures to prevent dengue fever. The content and pictures are adapted from the Food and Environmental Hygiene Department’s website. What is dengue fever?. Dengue fever is prevalent in regions 。 Transmitted by , it is an acute viral disease.
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Measures to prevent dengue fever The content and pictures are adapted from the Food and Environmental Hygiene Department’s website.
What is dengue fever? • Dengue fever is prevalent in regions。 • Transmitted by , it is an acute viral disease. • Prevalent in over countries and regions, and about 2 billion world population are under threat of its infection. tropical and subtropical mosquito bites 60
What are the symptoms of dengue fever … • High fever for 3 to 5 days • Severe headache • Muscle and joint pain • Pain behind the eyes • loss of appetite, nausea • Rash • Severe cases may have bleeding, shock and even death incubation period ranges from 3 – 14 days
How does it spread? • Transmitted by mosquitoes, cannot be directly transmitted from person to person.。 • The vectors that spread the disease include: • Aedes aegypti • Aedes albopictus Found in Hong Kong
How can you prevent it? • At present, there is no effective vaccine for dengue. So?
We should first understand the vector of dengue fever- Aedes albopictus
Profile of Aedes albopictus • Name • Class • Origin of birth • Food • Active time • Characteristics • Aedes albopictus • Insect • South of Liaoning, east of Shaanxi, more common in the south of the Yangtze River • Blood(female) • Daytime, especially 2 hours after sunrise and several hours before sunset • Spread dengue virus
Life cycle of Aedes albopictus • eggs:Usually laying eggs in stagnant water, a female mosquito can produce a time of about one hundred eggs.
Life cycle of mosquitoes • Larva:Like a caterpillar, it floats with a respirator connecting it to the water surface.
Life cycle of mosquitoes Pupa: Like a circular ball, the pupa comes to the water surface to breathe with a respirator.
Life cycle of mosquitoes • Adult:breaks out of the pupa and leaves the water.
The four stages take 7 days to complete. The first 3 stages proceed in water. So the best way to eliminate mosquito breeding is to remove stagnant water.
Precautionary measures to avoid mosquitoes bites • Wear long-sleeved clothes and long trousers • Use insect repellent over exposed parts of the body when outdoors • Use mosquito screens or nets when a room is not air-conditioned
Please say how they remove stagnant water and eliminate mosquito breeding
Answers: Leave no water in the saucers under flower pots Dispose of rubbish properly Pierce the tyres Cover tightly all water containers