The vector-borne dengue virus infection spreads via the bite of a striped Aedes aegypti and Aedes albopictus mosquito that has previously bitten an infected person. Aedes aegytpi, a species of mosquito, is the carrier of any one of the four closely related dengue virus serotypes — DEN 1, DEN 2, DEN 3 and DEN 4. The mosquito flourishes during rainy seasons but can breed in water-filled flowerpots, plastic bags, and cans year-round. One mosquito bite can cause the disease.
The virus is not contagious and cannot spread directly from person to person. It is mosquito-borne, so there must be a person-to-mosquito-to-another-person pathway. A mosquito bites a dengue-infected person and becomes infected with dengue. That mosquito then bites another person and passes the dengue virus infection to that person. The full life cycle of the virus involves the Aedes mosquito as the vector (transmitter) and the human as the source of infection.
Avoiding mosquitoes is important to avoid contracting dengue fever. In dengue-endemic tropical and sub-tropical areas, you should wear light-colored long-sleeved shirts and long pants or trousers, use insect repellant, stay or sleep indoors in air conditioning when possible and use mosquito netting over the bed if available.
What is the incubation period for dengue fever?
After being bitten by a mosquito carrying the virus, the incubation period for dengue fever ranges from 3 to 15 (usually 5 to 8) days before the signs and symptoms of dengue appear in stages.
Symptoms of Dengue
Symptoms of dengue fever may include high fever, severe headaches, pain behind the eyes, severe joint and muscle pain, fatigue, nausea, vomiting, skin rash and mild bleeding.
General advice for patients on home-care
— Even if you are positive (+) for dengue NS1 Antigen test, you may not need immediate hospitalisation.
— Negative (-) NS1 test does not exclude dengue illness.
— Home care should be always guided by a qualified doctor.
— Hospital admissions will be determined by platelet count of the latest complete blood count (CBC).
Platelets in our blood influence the coagulation process and are responsible for preventing bleeding. For this reason, it is recommended that you keep them within the advisable parameters.
Dengue fever can lower the platelet count and could turn fatal.
If the platelet count is significantly low due to dengue fever, one must consult a specialist doctor as early as possible and follow his instructions.
Accurate and timely diagnosis of dengue virus is important for early detection of dengue virus infection. The NS1 test should be taken on the very first day of the fever striking. It holds relevance after 24 hours. Dengue IgM is usually detectable in primary infection between 5 to 7 days after fever, while dengue IgG appears after 7 days. Therefore, the appearance of dengue IgM or IgM/IgG is mostly found in the primary infection depending on the time window of test; while dengue IgG usually appears in the secondary infection in the early days of infection with or without dengue IgM. Based on the tests from different geographic regions, our dengue IgG/IgM test has the sensitivity with clear signal over 90% for all four dengue serotypes, and equal sensitivity tested in the different geographic region, the specifity is over 95%
Fluid management for Dengue patients
- Fluids should include not only water but also certain electrolyte solutions such as fruit juice, papaya juice, green coconut water, chicken soup, yogurt, etc.
- Drink enough fluids to maintain a normal urine output.
- If the body weight is between 30 to 50 kilogrammes, take fluids double the weight in millilitres (ml) per hour, according to medicine specialist doctor’s opinion.
When should the CBC be repeated?
- Do the CBC in 8-12 hours intervals as recommended by your doctor.
- Do not delay showing the report to your doctor (at least within 3 hours) to get medical advice.
- If the platelet count has reached a low value nearing 100,000/ml, see your doctor immediately.
- When you see the doctor, bring all your blood investigation reports done during this fever episode.
- Use Paracetamol (acetaminophen) only. Follow your doctor’s instructions on the dose of
- Use tepid sponging to bring down the fever in between the Paracetamol dosing. Soak a clean towel in moderately warm water, then squeeze the excess water away and wipe the body to reduce fever.
Proper home-care for Dengue Patients
Physical rest is highly recommended.
Staying at home without exerting yourself to any stress is ideal.
Consume sufficient fluids to stay hydrated and maintain the body’s electrolyte balance.
When to get alarmed
The symptoms may develop into serious problems including dengue hemorrhagic fever, a rare complication characterized by high fever, damage to lymph and blood vessels, bleeding from the nose and gums, enlargement of the liver, and failure of the circulatory system. Such symptoms may progress to massive bleeding, shock, and death. This is called dengue shock syndrome (DSS).