Dengue Fever

Dengue fever, also known as breakbone fever, is an infectious tropical disease caused by the dengue virus. The virus has four different types. Infection with one type usually gives lifelong immunity to that type, but only short-term immunity to the other types.

The four dengue viruses originated in monkeys and independently moved to humans in Africa or Southeast Asia between 100 and 800 years ago.

The current situation of Dengue fever in Mombasa

The first laboratory confirmed case was reported by Kenya Medical Research Institute (KEMRI) on 7 Mar 2013. As of 26 Apr 2013, 83 of 148 (56%) blood samples collected from residents of Mombasa who visited health facilities with dengue-like illness tested positive for dengue virus.

This is the second town in Kenya to have reported cases of dengue since 2011; cases were reported in Mandera town in September 2011 (1300 cases) and in January 2013 (190 cases).


Dengue virus is transmitted primarily by mosquitoes which typically bite during the day, particularly in the early morning and in the evening, but they are able to bite and spread the infection at any other time of the day.

Dengue can also be transmitted via infected blood products and through organ transplant. Vertical transmission (from mother to child) during pregnancy or at birth has been reported.

The Mosquito

The mosquitoes involved belong to a class called Aedes mosquitoes. These live in Tropical and Subtropical urban regions.

Progress of illness

The course of infection is divided into three phases:

  1. Febrile phase
  2. Critical phase
  3. Recovery phase.

Management/Treatment for Dengue Fever

There is no specific medicine to treat dengue infection. Management is therefore supportive. Use of either oral or intravenous rehydration is adopted for mild or moderate disease, while intravenous fluids and blood transfusion is for more severe cases. Management entails:

a) Control the fever

  • Give drugs to control fever as prescribed
  • Sponge patient’s skin with cool water if fever stays high.

b) Prevent dehydration

This occurs when a person loses too much fluid from high fevers, vomiting, or poor oral intake.

  • Give plenty of fluids and watch for signs of dehydration.
  • Take patient to a clinic or emergency room if any of the following signs develop
  • Decrease in urination, check number of wet diapers or trips to the bathroom
  • Few or no tears when child cries
  • Dry mouth, tongue or lips
  • Sunken eyes
  • Restlessness or overly agitated or confused
  • Fast heart beat (more than 100/min)
  • Cold or clammy fingers and toes
  • Sunken fontanel in infant


c) Bed rest.

  • Let patient rest as much as possible

Prevention of Dengue Fever

As there is no commercially available vaccine, prevention is sought by reducing the habitat and the number of mosquitoes and limiting exposure to bites.

The best way to prevent the disease is to prevent bites by infected mosquitoes. This involves protecting yourself and making efforts to keep the mosquito population down.

To protect yourself:

  • Cover the exposed skin including hands feet and head.
  • Use an appropriate insect repellent as directed. If you are also using sunscreen, apply sunscreen first and insect repellent second.
  • Follow package directions for using repellent on children.
  • Use permethrin-treated clothing. You can buy pretreated clothing or treat them yourself.
  • Stay away from heavily populated residential areas, if possible.
  • When indoors, use air conditioning if available.
  • Make sure window and door screens are secure and free of holes. If sleeping areas are not screened or air conditioned, use mosquito nets.
  • If someone in your home gets dengue fever, be especially vigilant about efforts to protect yourself and other family members from mosquitoes.

To reduce the mosquito population:

To reduce the mosquito population:

Get rid of places where mosquitoes can breed. These include old tires, cans, or flower pots that collect rain.

If you have symptoms of dengue, speak to your doctor or visit the nearest health facility!