Ref: CHB/News Bulletin/006/2013
Dengue fever Outbreak!
The Tanzania Ministry of Health and Social Welfare is investigating an outbreak of dengue fever, in Dar es Salaam and the surrounding areas. A public health team found several persons with dengue fever while investigating an increase in malaria-like illness. Further confirmatory testing is taking place. Earlier this year, dengue outbreaks have been reported in Somalia and Kenya, including a large outbreak in Mombasa.
Dengue fever
This is a disease caused by a virus spread by the bite of an infected Aedesaegypti mosquito. The mosquito becomes infected when it bites a person with dengue virus in their blood. It can’t be spread directly from one person to another person.
The incidence of dengue has grown dramatically around the world in recent decades. Over 2.5 billion people – over 40% of the world’s population – are now at risk from dengue. It is common in tropical and subtropical regions including parts of the Caribbean, Central and South America, Western Pacific Islands, Australia, Southeast Asia, and Africa. WHO currently estimates there is an estimated 100 million cases of dengue fever occur worldwide.
Infected humans are the main carriers and multipliers of the virus, serving as a source of the virus for uninfected mosquitoes. Patients who are already infected with the dengue virus can transmit the infection (for 4–5 days; maximum 12) via Aedes mosquitoes after their first symptoms appear.
Symptoms:
The infection causes flu-like illness, and occasionally develops into a potentially lethal complication called severe dengue.
Dengue should be suspected when a high fever (40°C/ 104°F) is accompanied by two of the following symptoms: severe headache, pain behind the eyes, muscle and joint pains, nausea, vomiting, swollen glands or rash. Symptoms usually last for 2–7 days, after an incubation period of 4–10 days after the bite from an infected mosquito.
Severe dengue (previously known as dengue hemorrhagic fever) is a potentially deadly complication due to plasma leaking, fluid accumulation, respiratory distress, severe bleeding, or organ impairment. Warning signs occur 3–7 days after the first symptoms in conjunction with a decrease in temperature (below 38°C/ 100°F) and include: severe abdominal pain, persistent vomiting, rapid breathing, bleeding gums, fatigue, restlessness, blood in vomit. Also get bruises without bumping into anything,they may get purple spots on the skin.
The symptoms may progress to massive bleeding, shock, and death. This is called dengue shock syndrome (DSS). The next 24–48 hours of the critical stage can be lethal; proper medical care is needed to avoid complications and risk of death.
Diagnosis of dengue fever is done by symptoms in the endemic areas. The earliest change detectable on laboratory investigations is a low white blood cell count, which may then be followed by low platelets and metabolic acidosis.
Treatment for Dengue Fever
There is no specific medicine to treat dengue infection. If you think you may have dengue fever, you should use pain relievers with acetaminophen and avoid medicines with aspirin, which could worsen bleeding. You should also rest, drink plenty of fluids, as fluid balance and maintenance is critical to severe dengue care.
Prevention and control
At present, there are no approved vaccines for the dengue virus. The only method to control or prevent the transmission of dengue virus is to combat vector mosquitoes through:
- Eliminating A. aegyptis habitats – This is done by emptying containers of water or by adding insecticides or biological control agents to these areas
- covering, emptying and cleaning of domestic water storage containers on a weekly basis;
- applying appropriate insecticides to water storage outdoor containers;
- Using of personal household protection such as window screens, long-sleeved clothes, using mosquito netting, and using of insect repellent.
Source: http://www.who.int/mediacentre/factsheets/fs117/en/
Compiled by Neelam.A Ismail