Dengue and severe dengue

29 September 2019

Dengue is a mosquito-borne viral disease that has rapidly spread in all regions of WHO in recent years. Dengue virus is transmitted by female mosquitoes mainly of the species Aedes aegypti and, to a lesser extent, Ae. albopictus. These mosquitoes are also vectors of chikungunya, yellow fever and Zika viruses. Dengue is widespread throughout the tropics, with local variations in risk influenced by rainfall, temperature, relative humidity and unplanned rapid urbanization.

Ian Jabobs
An Ae. aegypti mosquito, one of the primary vectors for the transmission of dengue fever around the world, gets a blood meal from a host.

Ae. aegypti mosquito: one of the primary vectors for the transmission of dengue fever around the world, gets a blood meal from a host

An Ae. aegypti mosquito, one of the primary vectors for the transmission of dengue fever around the world, gets a blood meal from a host.
© Ian Jabobs

WHO
The mosquitoes thrive in areas close to human population (urban areas).

The dengue mosquitoes thrive in areas close to human population (urban areas)

The mosquitoes thrive in areas close to human population (urban areas). The dengue mosquito lays its eggs in water-filled containers inside the house and surrounding areas of dwellings (this includes non-used bottles, containers, discarded waste, tyres etc… which hold water).
© WHO

WHO
The dengue mosquito lays its eggs in water-filled containers inside the house and surrounding areas of dwellings.

The dengue mosquito lays its eggs in water-filled containers inside the house and surrounding areas of dwellings

The dengue mosquito lays its eggs in water-filled containers inside the house and surrounding areas of dwellings (this includes non-used bottles, containers, discarded waste, tyres etc… which hold water). A mosquito egg can develop in larva, pupa and adult between 7 to 10 days. The elimination of the hatcheries is key to reduce the mosquito population.
© WHO

Erika pineros
There is no vaccine or specific medication for dengue fever. Patients should seek medical advice, rest and drink plenty of fluids. Paracetamol can be taken to bring down fever and reduce joint pains. With proper medical care and early recognition, case-fatality rates are below 1%.

There is no vaccine or specific medication for dengue fever

There is no vaccine or specific medication for dengue fever. Patients should seek medical advice, rest and drink plenty of fluids. Paracetamol can be taken to bring down fever and reduce joint pains. With proper medical care and early recognition, case-fatality rates are below 1%.
© Erika pineros

PAHO/ J. E. Cogan
An entomologist sets up a trap to collect adult mosquitoes in a house. Afterwards he will bring it to the laboratory to study its behavior and pattern changes as for example insecticide resistance.

An entomologist sets up a trap to collect adult mosquitoes in a house

An entomologist sets up a trap to collect adult mosquitoes in a house. Afterwards he will bring it to the laboratory to study its behavior and pattern changes as for example insecticide resistance.
© WHO PAHO/ J. E. Cogan

André Luiz D. Takahashi
Window and door screens, air conditioning reduces the risk of mosquitoes coming into contact with the household members. Mosquito nets (and/or insecticide-treated nets) will also provide additional protection to people sleeping during the day, or protect against other mosquitoes which can bite at night (such as malaria). Household insecticides aerosols, mosquito coils or other insecticide vaporizers maybe also reduce biting activity.

Window and door screens, air conditioning reduces the risk of mosquitoes coming into contact with the household members

Window and door screens, air conditioning reduces the risk of mosquitoes coming into contact with the household members. Mosquito nets (and/or insecticide-treated nets) will also provide additional protection to people sleeping during the day, or protect against other mosquitoes which can bite at night (such as malaria). Household insecticides aerosols, mosquito coils or other insecticide vaporizers maybe also reduce biting activity.
© André Luiz D. Takahashi

Luiz Burdiez
The best preventive measure for areas infested with Aedes mosquito is to eliminate the mosquitoes’ egg laying sites – called source reduction.

The best preventive measure for areas infested with Aedes mosquito is to eliminate the mosquitoes’ egg laying sites – called source reduction

The best preventive measure for areas infested with Aedes mosquito is to eliminate the mosquitoes’ egg laying sites – called source reduction. Lowering the number of eggs, larvae and pupae will reduce the number of emerging adult mosquitoes and the transmission of the disease.
© Luiz Burdiez