Dengue Can Recur and Be More Severe, Experts Warn

Most patients who come with high fever every monsoon have the same question, 'Doctor, I had dengue a few years ago. Can I get dengue again?'

After the test report confirms dengue a few days later, they ask another question, 'I thought I was immune now.'

Although this thought is natural, it is one of the biggest misconceptions about dengue. Some diseases like chickenpox develop lifelong immunity after a single infection. But in dengue, recovery from one infection does not provide lifelong protection.

If a person is later infected with a different type (serotype) of the dengue virus, they can get dengue again. More importantly, the second infection can be more fatal than the first in some individuals. This does not mean everyone will have a severe condition with a second dengue infection, but ignoring the symptoms as mild can be dangerous.

Why can dengue occur more than once?

Dengue is caused by four different but related virus types (serotypes): DENV-1, DENV-2, DENV-3, and DENV-4.

After being infected with one serotype, long-term immunity develops only against that specific type of virus. Immunity against the other three types does not develop. Therefore, if a person is infected with another serotype later, they can get dengue again. In countries like India and other South Asian countries, where multiple serotypes are active simultaneously, reinfection is not uncommon.

Why can the second dengue infection be more severe?

After the first infection, the body produces antibodies against that virus. However, when a different serotype infects for the second time, these antibodies cannot completely destroy the virus. In some cases, they help the virus enter certain immune cells of the body. This is called Antibody-Dependent Enhancement (ADE).

This can cause excessive inflammation in the body, plasma leakage from blood vessels, a drop in blood pressure, fluid accumulation in the chest or abdomen, bleeding, Dengue Shock Syndrome, or affect other organs.

However, not all second infections are severe. Many patients recover completely with standard treatment. But individuals who have had dengue before should take special precautions if symptoms reappear.

The most critical period begins when the fever starts to subside

Many people think the disease is improving when the fever starts to decrease. But in dengue, the opposite can happen. The most critical phase begins from the third to the seventh day of illness, especially when the fever starts to subside. This is when the chances of plasma leakage, bleeding, or shock are higher.

Therefore, regular medical supervision is extremely necessary during this period.

Never ignore these warning signs

Initial symptoms of dengue may include: high fever, headache, pain behind the eyes, body and joint pain, nausea, skin rash. However, if symptoms like persistent vomiting, severe abdominal pain, bleeding from the nose or gums, blood in vomit or stool, excessive sleepiness or fainting, difficulty breathing, cold extremities, increased restlessness, or decreased urination occur, one should go to the hospital immediately.

These symptoms should not be treated at home.

Platelets are not everything

Many people assess the severity of dengue solely based on low platelet count. Although platelets are important, treatment decisions are not based on them alone. Doctors make treatment decisions by evaluating the patient's overall health condition, including hydration level, blood pressure, hematocrit, and signs of plasma leakage.

Some patients remain stable even with very low platelets, while others may develop serious complications even if their platelets are not significantly low.

Avoiding mosquito bites is the most effective measure

Even after having dengue once, precautions should not be reduced, as infection with another serotype is possible. Therefore, to prevent dengue: using mosquito repellents, wearing full-sleeved clothing, using nets on windows and doors, and preventing water from accumulating in and around the house are considered effective measures.

Recovery from dengue once does not develop lifelong immunity. Infection with a different serotype can occur a second time, and in some cases, it can be more severe than the first infection. However, with timely testing, adequate fluid intake, recognition of warning signs, and especially medical supervision during the period when the fever starts to subside, most patients recover successfully.

Vigilance, timely treatment, and correct information are the most effective defenses against dengue.

With the help of the agency