Epidemiology
Also known as "Tropical Flu", this is an arbovirosis due to a Flavivirus, (Flaviviridae family), of which there are 4 types (DEN-1, DEN-2, DEN-3 and DEN-4).
It is transmitted by the bites of female mosquitoes of the genus Aedes (Aedes aegypti, Aedes albopictus, Aedes polynesiensis, etc.). Aedes bites mainly during the day (mostly in the early morning and at the end of the day).
Currently, dengue is endemic in over one hundred countries of Africa, the Americas (including the Caribbean), the Eastern Mediterranean, Southeast Asia and the Western Pacific.
It is the most widespread arbovirosis in the world. 2/5 of the global population is exposed to this risk. Every year, 60 to 100 million persons are infected worldwide, and 20,000 persons die from the hemorrhagic form of dengue.
Symptoms
There are 3 forms: "classic dengue", which is generally without complications, the "haemorrhaging form", which is extremely severe, sometimes even deadly, and dengue with "shock syndrome".
- Classic form :
- After 2 to 7 days of incubation, a high fever (>39°C) appears, often accompanied by headaches, vomiting, joint and muscle pain, and a measles-like rash on the torso extending over the face and extremities.
After 3 to 4 days, a brief remission is observed, then the symptoms intensify: mild haemorrhaging (bleeding nose or gums, etc.) ecchymosis, etc. After a week, the symptoms subside.
This form spontaneously progresses to recovery without sequelae in the majority of cases, although the convalescent period may be long.
- Hemorrhagic form and dengue with shock syndrome :
- In certain cases (most often in children under 15 years of age), after 2 to 7 days have passed and the temperature has returned to normal, the infection may progress to hemorrhagic dengue or dengue with shock syndrome.
Hemorrhagic dengue is characterised by a persistent fever and multiple haemorrhages (gastrointestinal, cutaneous and cerebral). This form is deadly in 2.5% of cases.
There can also be a shock syndrome (restlessness, increased heart rate and blood pressure, chills in the extremities) accompanied by abdominal pain.
In very rare cases, patients may develop neurological symptoms (seizures, partial paralysis, impaired consciousness) with or without hemorrhaging, requiring hospitalisation with a profile of acute encephalitis.
Treatment
Treatment consists of treating the symptoms only (fever, pain, etc.). Considering that there is a risk of haemorrhage, it is absolutely necessary to avoid the use of aspirin and anti-inflammatory drugs (ibuprofen, corticosteroids, etc.).
Prevention
1. Vaccination
There is no vaccine against dengue.
2. Prevention of insect bites
The only way to protect oneself is to avoid mosquito bites via personal protection:
- wearing ample clothing that covers the body,
- use of appropriate repellent product for the body and insecticide product for clothing (Moustifluid High Protection Tropical Zones and Moustifluid Lotion For Fabrics and Clothing Tropical Zones)
- and repellent-sprayed mosquito nets (Moustifluid Lotion For Fabrics and Clothing Tropical Zones).
To fight the Aedes mosquito, protection must be maximised at dawn and at sunset: this is the period when the mosquito is most active, although it can also bite during the day.