Dengue fever is an infectious disease caused by the dengue virus, transmitted by Aedes aegypti mosquitoes. Common symptoms include sudden high fever, pain behind the eyes, muscle and joint aches, fatigue, loss of appetite, and skin rash.

From the 4th day, the disease can worsen even after the fever subsides, with signs such as restlessness, lethargy, abdominal pain, nausea, nosebleeds, bleeding gums, and black stools. Patients risk complications like hemorrhage, shock, multi-organ failure, pleural effusion, and even death.

A study published in the European Heart Journal (8/2025), based on 80 patients at Oxford University Hospital in Bangalore, India, indicated that blood type O had the highest incidence of dengue fever (28,75%) and dengue shock (nearly 44%).

Blood test for dengue fever diagnosis. Photo: Vecteezy.

Blood test for dengue fever diagnosis. Photo: Vecteezy.

Another study in the US National Library of Medicine (1/2025), involving 88 patients aged one to 18 in India, also noted a higher incidence and severe complications among those with blood type O (46,1% and 56,2%).

However, a study at Lady Reading Hospital Peshawar, Pakistan (2020), involving 160 patients, suggested that blood type B had a higher risk.

Scientists have not yet fully explained the link between blood type and dengue shock, but they confirm that no blood type is immune, and everyone is at risk of complications.

The dengue virus has 4 serotypes: Den-1, Den-2, Den-3, and Den-4. Individuals can contract the disease multiple times due to different serotypes, with subsequent infections potentially leading to more severe outcomes. For prevention, people should keep their living areas clean and well-ventilated, discard stagnant water around their homes, regularly change water in flower vases and plant pots, and make a habit of sleeping under mosquito nets, even during the day.

Additionally, dengue vaccination offers effective protection. The current vaccine is for children aged four and older, and adults. The vaccination schedule involves two doses, given three months apart. Women should complete the vaccination schedule at least one month, and ideally three months, before pregnancy. Completing both vaccine doses provides over 80% protection against the disease and reduces the risk of hospitalization due to dengue by up to 90%.

Doctor Pham Hong Thuyet

Medical Manager, VNVC Vaccination System

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