In any type of infection, after contracting the disease, the body will create antibodies to help fight the disease if it is infected again with the immunity formed. In dengue fever, after contracting the disease, the body also has protective immunity but only with the corresponding type of virus infected. Although this immunity is quite stable, the dengue virus that causes the disease has 4 different types, so it is possible to get sick again with other types of viruses; people can get dengue fever 4 times with 4 types of dengue virus.
In any type of infection, after contracting the disease, the body will create antibodies to help fight the disease if it is infected again with the immunity formed. In dengue fever, after contracting the disease, the body also has protective immunity but only with the corresponding type of virus infected. Although this immunity is quite stable, the dengue virus that causes the disease has 4 different types, so it is possible to get sick again with other types of viruses; people can get dengue fever 4 times with 4 types of dengue virus.
Dengue fever is an acute mosquito‐borne dengue virus infection that can cause large epidemics. According to scientists, in our country, the epidemic is prevalent in some localities in the Mekong Delta, the Northern Delta and the Central coastal region. The causative agent is the Dengue virus belonging to the Flavivirus group, the Flaviviridae family with 4 serotypes denoted as DEN‐1, DEN‐2, DEN‐3 and DEN‐4. The disease is transmitted from sick people to healthy people through two types of mosquitoes that transmit the disease, Aedes aegypti and Aedes albopictus, from blood bites. Everyone from infants to adults who do not have specific immunity to dengue fever can get the disease. After recovering from the disease, they will be immune for life to the virus type that causes the disease but will not be cross‐protective against other types of dengue virus. If infected a second time with a different virus type, the patient may be infected with a more severe level and is more likely to develop dengue shock syndrome.
With the above characteristics, testing the patient’s serum and dengue virus is very necessary to record information from the patient. Collect the patient’s specimens with blood samples within 5 days from the date of onset of the disease to diagnose and identify the type of dengue virus causing the disease by isolating the virus and identifying genetic material or antigens. Blood samples after 5 days from the date of onset of the disease are used to diagnose dengue virus infection by detecting IgM antibodies. In fact, rapid tests can be used for screening in diagnosing the virus causing the disease. Note that samples must be sent to the Institute of Hygiene and Epidemiology or the Pasteur Institute to identify the circulating dengue virus type.
In parallel with testing to detect the type of Dengue virus causing the disease in patients, the Centers for Preventive Medicine, Institute of Hygiene and Epidemiology or Pasteur Institute also need to perform the necessary tests to detect and classify the type of Dengue virus on mosquito samples collected from the field where the epidemic occurred where the patient is residing for comparison.
Determining the type of Dengue virus that causes dengue fever is necessary information that should be provided to patients. At the same time, patients are advised that although the body has immunity to this type of Dengue virus after being infected, if they do not take good preventive measures, they can get sick again and again due to being infected with a different type of Dengue virus than the previous time because there are up to 4 different types of the virus that causes the disease. In other words, although immunity to dengue fever after being infected is quite stable, potentially long‐lasting and lifelong, patients can get sick up to 4 times due to being infected with 4 different types of Dengue virus that cause the disease; the severity of the disease the next time is always more severe than the previous time with many risks of clinical illness such as dengue shock syndrome that threatens life. Therefore, disease prevention measures are always better than treatment measures, and measures to kill mosquito larvae that transmit the disease to prevent the disease are always better than measures to kill adult mosquitoes.
