Dengue fever is an illness caused by the transmission of dengue virus (DENV) from bites of infected female mosquitoes, usually from the Aedes species. A mosquito is said to be infected when it is infected by the dengue virus. This occurs when the mosquito bites a person that is previously infected by dengue and the circulating virus inside the human body then infect the mosquito. Dengue virus is then transmitted to the other person when the infected mosquitoes bites other human beings and releases the dengue virus into the bloodstream of the human body.
In general, we know that after a person is infected with a virus, the body produces antibodies as a product from the immune system in an attempt to fight off the infection. The antibody is then present in the body and able to help the body ward off infections of the same virus in the future. This makes a person unable to catch the same disease in the future.
However, this does not apply to dengue fever. Dengue fever can recur in future and a person is able to be infected again with other virus types. Dengue virus exists in 4 serotypes, which are DENV-1, DENV-2, DENV-3 and DENV-4. When a person has been infected by one serotype and recovers, the body only produces antibodies against that one specific serotype. This means that when a person is exposed to the other 3 serotypes, a person will be infected by the subsequent serotypes as the existing antibody is unable to fight off the infection.
Unfortunately, reinfection by other serotypes pose great threat as it is likely that subsequent infection could lead to severe dengue. For instance, if a person was previously infected by serotype DENV-1 and catches serotypes DENV-2 or DENV-3 in future, they are likely to suffer severe dengue due to the cross-reaction immune reaction. The most dangerous serotypes are the DENV-2 since it has been associated with severe forms of dengue such as Dengue Haemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS).
Dengue fever usually starts with high grade fever that lasts for 2 to 7 days. Symptoms commonly reported with dengue fever such as severe headaches, muscle pain (myalgia), joint pain (arthralgia), pain behind the eyes (retro-orbital headaches) and skin rash should be a concern and raise suspicion that a person is experiencing dengue infection. Such symptoms should cause great concerns if there are known cases of dengue fever around the neighbourhood area.
Warning signs like severe sudden abdominal pain, persistent vomiting that lasts more than 3 times in 24 hours, sudden bleeding gums or nose and vomiting blood or presence of blood in stool should be a sign that a person needs to go to a nearby healthcare facility or emergency room. This is because such signs could lead to a severe form of dengue fever. Severe dengue needs to be taken care of by medical professionals immediately as during the critical phase, a person’s condition may quickly deteriorate and symptoms may get worse easily.
Critical phase occurs in the 3rd until the 7th days after the initial symptoms of dengue are exhibited. This phase lasts for 24 to 48 hours. Due to this phase, a person may need to be admitted or stay in hospital for a few days to enable observations from healthcare professionals. Observations help a person to get immediate treatment or supportive care if a person shows warning signs. This can help reduce the likelihood of a person falling into a life-threatening condition and to prevent complications such as internal bleeding or organ failure from occurring.
It can be concluded that a dengue fever may recur due to the existence of the other serotypes infecting a person. A person needs to be treated the same as the previous infections although he or she has experienced dengue fever in the past. Plus, reinfection should cause great concerns as the likelihood of severe dengue is high in this case. Get Vaccinated.