2. OVERVIEW
Dengue (DENG-gey) fever is a mosquito-borne illness that occurs in tropical and
subtropical areas of the world. Mild dengue fever causes a high fever and flu-like
symptoms. The severe form of dengue fever, also called dengue haemorrhagic fever,
can cause serious bleeding, a sudden drop in blood pressure (shock) and death.
3. EPIDEMIOLOGY
Millions of cases of dengue infection occur worldwide each year. Dengue fever is most
common in Southeast Asia, the western Pacific islands, Latin America and Africa. But the
disease has been spreading to new areas, including local outbreaks in Europe and
southern parts of the United States.
Researchers are working on dengue fever vaccines. For now, in areas where dengue
fever is common, the best ways to prevent infection are to avoid being bitten by
mosquitoes and to take steps to reduce the mosquito population.
4. PATHOLOGY
Plasma leakage is specific to the pleural and peritoneal surfaces: plasma leakage results
from cytokine mediated increase in vascular permeability.
The immune system is implicated in the pathogenesis of DHF owing to the increased
propensity to develop DHF with secondary dengue infection.
The pathogenesis of bleeding in DHF is unclear even though well-recognised
coagulation disturbances do exist.
5. MODE OF TRANSMISSION
Dengue viruses are spread to people through the bites of infected Aedes species
mosquitoes (Ae. aegypti or Ae. albopictus). These are the same types of mosquitoes
that spread Zika and chikungunya viruses.
A pregnant woman already infected with dengue can pass the virus to her foetus
during pregnancy or around the time of birth.
Rarely, dengue can be spread through blood transfusion, organ transplant, or through
a needle stick injury.
6. SYMPTOMS/CF
Patients with Dengue fever usually present with a high fever — 104 F (40 C) — and any of the following signs and
symptoms:
Headache
Skin erythema
Myalgia
Bleeding (any haemorrhagic manifestations)
Muscle, bone or joint pain
Nausea
Vomiting
Pain behind the eyes
Swollen glands
Rash
7. Most people recover within a week or so. In some cases, symptoms worsen and can
become life-threatening. This is called severe dengue, dengue haemorrhagic fever or
dengue shock syndrome.
Severe dengue: happens when the blood vessels become damaged and leaky. And the
the number of clot-forming cells (platelets) in the bloodstream drops. This can lead to
shock, internal bleeding, organ failure and even death.
8. WARNING SIGNS OF SEVERE DENGUE
FEVER
The warning signs usually begin the first day or two after the fever goes away, and may
include:
Severe stomach pain
Persistent vomiting
Bleeding from gums or nose
Blood in urine, stools or vomit
Bleeding under the skin, which might look like bruising
Difficult or rapid breathing
Fatigue
Irritability or restlessness
9. DIAGNOSIS
Dengue fever is diagnosed thorough careful clinical (History & Examination) and
laboratory procedures which includes:
Nucleic acid amplification tests (NAATs)
Serologic tests
Cross-reactive flaviviruses
And IgG antibody testing amongst others.
10. MANAGEMENT
APPROACH: Dengue fever is usually a self-limited illness. There is no specific antiviral
treatment currently available for dengue fever.
Supportive care with analgesics, fluid replacement, and bed rest is usually sufficient.
Acetaminophen may be used to treat fever and relieve other symptoms.
Patients with dengue haemorrhagic fever or dengue shock syndrome may require
intravenous volume replacement. Plasma volume expanders can be used in patients
who do not respond to isotonic fluids.
Aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), and corticosteroids should be
avoided.
Management of severe dengue requires careful attention to fluid management and
proactive treatment of haemorrhage.
11. PREVENTION:
The only way to truly prevent dengue virus acquisition is to avoid being bitten by a vector
mosquito.
VACCINATION:
One vaccine is currently approved for the prevention of dengue infection. Sanofi Pasteur
registered Dengvaxia (CYD-TDV), a live recombinant tetravalent vaccine, in several countries in
late 2015-2016, with Mexico being the initial country to register the vaccine in December 2015.
12. CONCLUSION
Dengue fever is a mosquito-borne illness that occurs in tropical and subtropical areas of
the world which can be transmitted transplacental or rearely through blood transfusion
and organ transplant.
It is characterized by high fever and flu-like symptoms amongst others.
The only way to prevent Dengue fever is to avoid mosquito bites and prevent mosquito
population.
It is a self-limited illness. There is no specific antiviral treatment currently available for
dengue fever
Supportive care with analgesics, fluid replacement, and bed rest is usually sufficient in
management of dengue fever.
