Dengue Fever

Dengue Fever is an acute illness of sudden onset that usually follows a benign course with symptoms such as headache, fever, exhaustion, severe muscle and joint pain, and swollen lymph nodes (glands), but in some individuals complications might develop and severe illness might result.

What causes Dengue Fever?
Dengue Fever is caused by the Dengue virus, a member of the Flavivirus group. There are fouracknowledged types of Dengue viruses designated as types 1, 2, 3 and 4. Periodic epidemics are associated with the emergence or reemergence of different serotypes. The reinfection of an individual by a differenttype (heterotypic reinfection) may trigger complex immunopathologic mechanisms leading to thetwo most severe manifestations of the disease: Dengue Haemorrhagic Fever (DHF) and Dengue ShockSyndrome (DSS).

Dengue viruses are transmitted by mosquitoes of the Aedes group. These are relatively small mosquitoes that feed exclusively on humans. Predominantly on humans and less so on other animals. They tend to bite during the day and are usually found resting in dark places inside human housing.

They breed in small deposits of relatively clean water in or around human housing (flower pots,saucers under plant pots, old tires, etc.).

The virus that causes Dengue Fever is not contagious and cannot be spread directly from person to person. There must be a person-to-mosquito-to-another-person pathway.

What are the symptoms of Dengue Fever?
Symptoms of Dengue Fever might vary from one individual to another. In some cases the symptoms are very mild, but symptoms can become very severe and life-threatening. Symptoms include the following:

• High fever (> 100° F)

• Headache / myalgias

• Retro-orbital pain (Pain behind the eyes)

• Lymphadenopathies (cervical/occipital)

• Maculo-papular rash

Other associated elements may include upper/lower respiratory involvement, pharyngitis, vomiting and diarrhea.

If you have symptoms suggestive of Dengue Fever you should seek medical attention early. Most cases of Dengue Fever do not need to be admitted to hospital, but a few do. Those patients who develop complications, or who develop dengue haemorrhagic fever or dengue shock syndrome, will require admission to hospital.

The reduction of dengue mortality requires an organized process to guaranteeing the early recognition, the treatment, and the referral of cases to hospital health care services, as necessary. Most dengue patients recover without requiring hospitalization.

What is Dengue Haemorrhagic Fever?
Dengue hemorrhagic fever is a more severe form of the viral illness. Manifestations include headache, fever, rash, and evidence of haemorrhage in the body. Petechiae (small red or purple blisters under the skin), bleeding in the nose or gums, black stools, or easy bruising, are all possible signs of hemorrhage. This form of Dengue Fever can be life – threatening and can progress to the most severe form of the illness, dengue shock syndrome.

What is the treatment for Dengue Fever?
Dengue Fever is caused by a virus. There is no specific medicine or antibiotic to treat it. For typical dengue, the treatment is purely concerned with relief of the symptoms (symptomatic). Rest and fluid intake for adequate hydration is important. Aspirin and nonsteroidal anti-inflammatory drugs should be avoided or only be taken under a doctor’s supervision because of the possibility of worsening haemorrhagic complications. Acetaminophen (Tylenol) may be given for severe headache and for joint and muscle pain (myalgia). Individuals with complications will require intensive care management in hospital.

How can Dengue Fever be prevented?
The transmission of the virus to mosquitoes must be interrupted to prevent the illness.The prevention of dengue requires control or eradication of the mosquitoes carrying the virus that causes dengue. In Anguilla, individuals are urged to empty stagnant water from old tires, trash cans, and flower pots to help decrease the number of aedes egypti mosquitoes. The community must become more involved in helping to control this mosquito. Individuals can use insect repellent on uncovered skin to help decrease insect bites as well. Individuals are also encouraged to wear loose, long-sleeved shirts and long pants when outdoors to decrease the risk of mosquito bites.

Conclusion
Dengue Fever is an acute febrile illness that is now occurring in several Caribbean countries. The recent heavy rains in Anguilla would likely lead to an increase in the number of aedes egypti mosquitoes and will increase the risk of Dengue Fever outbreak. Members of the community are being encouraged to take measures to prevent the breeding mosquitoes on the island and this will help to decrease the risk of a Dengue Fever outbreak.

Ask Your Doctor is a health education column and is not a substitute for medical advice from your physician. Dr Brett Hodge is an Obstetrician/Gynaecologist and Family Doctor who has over twenty five years in clinical practice. Dr Hodge has a medical practice in the Johnson Building in The Valley.