Dengue and Dengue Haemorrhagic fever (DHF) are caused by one of four closely related virus types from the same family of viruses. Infection from one type of Dengue Fever virus does provide immunity to that ‘type’, but does NOT provide cross-protective immunity to other ‘types’, so persons living in a Dengue Fever area can have four dengue infections during their lifetime.
Infection with a Dengue Fever virus can produce a spectrum of illness, from a ‘mild viral syndrome’ to a severe and fatal bleeding disorder called Dengue Haemorrhagic Fever (DHF). Important risk factors for DHF include age, (the young are worse off than older people), and an immune status that is compromised or reduced.
Dengue Fever is primarily an urban disease of the tropics. There are three areas world-wide that are currently at increased risk for travellers getting the disease: Western Pacific, South East Asia, Eastern Seaboard of Central and South America
Dengue Fever is transmitted by the bite of an infected mosquito. The viruses that cause it are maintained in a cycle that involves humans and a domestic, day-biting mosquito that prefers to feed on humans. Once infected, a mosquito remains infective for life.
The dengue fever mosquito (Aedes aegypti) is dependent on humans and never lives more than 90 metres from dwellings, thus guaranteeing her meals. The sound of her wings cannot be heard and she attacks from below or behind, e.g. underneath chairs and mainly at the feet and ankles.
The females are very nervous feeders, disrupting the feeding process at the slightest movement, only to return to the same or a different person to continue feeding moments later. Because of this behaviour the mosquito will often feed on several persons during a single blood meal and, if infective, may transmit the dengue virus to many people in a short time. It is not uncommon to see several members of the same household become ill with dengue fever within a 24-36 hour frame, suggesting that a single infective mosquito infected all of them
The clinical features of Dengue Fever vary according to the age of the patient. These may develop as soon as 5-7 days after infection.
Infants and young children may have a fever with a rash. Older children and adults may have a combination of any of the following:
high fever and chills
But opting out of some of these cookies may have an effect on your browsing experience.
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.