Dengue and blood pressure: Here’s how the two are linked

Dengue fever, a viral infection transmitted by the Aedes mosquito, can lead to high fever, severe headache, pain behind the eyes, joint and muscle pain, and fatigue. This infection that spreads from mosquitoes to humans, can be accompanied by nausea, vomiting, and skin rash too. While experiencing all this, your blood pressure may also go through changes. In fact, people with hypertension should be extra careful about this infection. On National Dengue Day, observed annually on May 16, know the link between dengue and blood pressure.

What is dengue fever?

Dengue fever is a viral infection that is transmitted mostly by Aedes mosquitoes, specifically Aedes aegypti. These mosquitoes thrive in tropical and subtropical climates, making dengue prevalent in different parts of the world, says internal medicine expert Dr Rituja Ugalmugle.

The dengue virus belongs to the Flaviviridae family. There are four distinct serotypes of the virus, DEN-1 through DEN-4. This virus is primarily transmitted to humans through the bite of infected Aedes mosquitoes, particularly Aedes aegypti and, to a lesser extent, Aedes albopictus. The mosquitoes get infected when they bite an infected person. After an incubation period of 4 to 10 days, the mosquito can then transmit the virus to other humans through subsequent bites. Dengue is not contagious, and only mosquitoes serve as vectors for transmission, says internal medicine expert Dr P Venkata Krishnan.

What are the symptoms of dengue fever?

Symptoms of dengue fever generally manifest within 4 to 10 days after being bitten by an infected mosquito. Common symptoms include:

• Suddenly having a high fever
• Severe headache
• Pain behind the eyes
• Fatigue
• Joint and muscle pain
• Nausea
• Vomiting
• Skin rash

Some people may also experience mild bleeding, such as nosebleeds, gum bleeding, or easy bruising. Dengue can also progress to dengue shock syndrome characterised by severe abdominal pain, persistent vomiting, bleeding gums, difficulty breathing, and signs of circulatory failure, which can be life-threatening if you don’t reach out to a doctor immediately.

What is the connection between dengue and blood pressure?

Dengue can affect blood pressure because of its impact on the circulatory system, says Dr Krishnan. Dengue fever often leads to low blood pressure (hypotension) because of fluid loss from vomiting, diarrhea, and dehydration caused by high fever. This can result in symptoms like dizziness and lightheadedness. In severe cases like dengue hemorrhagic fever or dengue shock syndrome, blood pressure can drastically drop, leading to hypotensive shock, a life-threatening condition.

In some cases, during the recovery phase, blood pressure may temporarily rise (hypertension) as the body replenishes fluids, but this generally resolves when the person recovers.

A significant association was found between hypertension (high blood pressure) and the development of severe dengue in adult patients, according to a 2022 study published in Plos One. Researchers suggested that people with dengue and underlying hypertension need closer monitoring for deterioration.

People living with hypertension are not inherently more prone to contracting dengue infection. However, hypertension can potentially aggravate the severity of dengue symptoms if a person becomes infected, says Dr Krishnan. This is because hypertension can weaken the cardiovascular system, making it difficult for the body to cope with the fluid loss and circulatory challenges associated with dengue fever. Also, certain medications used to manage hypertension, like beta-blockers, may affect immune function, potentially impacting the body’s ability to fight off the dengue virus.

How to manage high blood pressure in dengue?

You can do the following to manage high blood pressure and the mosquito-borne disease:

1. Hydration

Drink plenty of fluids, including water and fresh juices, to prevent dehydration, especially crucial during dengue fever. You should be hydrated, as there is a risk of fluid loss due to fever and sweating, says Dr Ugalmugle.

2. Medication management

People with both high blood pressure and dengue need to continue their prescribed hypertension medications unless otherwise directed by their doctor. These medications help in controlling blood pressure levels, reducing the risk of complications associated with hypertension during dengue infection.

3. Rest and monitoring

Rest is crucial for people with both high blood pressure and dengue. Adequate rest helps in lowering blood pressure and supports the body’s immune response to combat the dengue virus. Regular monitoring of blood pressure and dengue symptoms allows for early detection of any complications.

4. Dietary modifications

Adopting a healthy diet, which should be low in sodium, and rich in fruits, vegetables, whole grains, and lean proteins, can help in managing high blood pressure and support immune function during dengue infection. Limiting processed foods and high-sodium items helps in controlling blood pressure, while consuming nutrient-rich foods provides essential vitamins and minerals to aid recovery from dengue, says Dr Krishnan.

5. Prevent mosquito bites

Take measures to prevent mosquito bites, such as using insect repellent, wearing long-sleeved clothing, and using mosquito nets, especially during evening time. This helps reduce the risk of dengue transmission, says Dr Ugalmugle.

What to do if blood pressure becomes too low due to dengue?

If blood pressure becomes too low because of dengue, immediately contact your doctor. To address low blood pressure, you may be given intravenous fluids to restore fluid volume and improve blood pressure. In severe cases, medications to constrict blood vessels and increase blood pressure, like vasopressors, may be needed.

Dengue fever is an infection that spreads to people from mosquitoes. It may affect blood pressure, and people with hypertension need to be more cautious.