Dengue Fever

Dengue fever is a sickness spread by mosquitoes, found mostly in hot, humid parts of the world. It's like the flu, but it can be more serious. A mild case of dengue will make you feel very sick with a high temperature and flu-like symptoms like body aches and a headache. In severe cases, called dengue hemorrhagic fever, it can lead to dangerous problems like uncontrolled bleeding, a sudden drop in blood pressure (which can be life-threatening), and even death.

Millions of people get dengue fever every year. It's most common in places like Southeast Asia, the islands of the western Pacific, Latin America, and Africa. However, it's also showing up in new places, such as parts of Europe and the southern United States. Scientists are developing vaccines to help protect people from dengue fever, but for now, the best way to avoid getting it is to prevent mosquito bites and control mosquito populations in your area. This means things like using insect repellent, wearing long sleeves and pants when outdoors, and getting rid of standing water where mosquitoes breed.

Many people don't show any symptoms of dengue fever. When symptoms do appear, they often resemble other illnesses, like the flu. They usually start 4 to 10 days after a mosquito bite.

Dengue fever typically brings a high fever (104°F or 40°C) along with several other symptoms:

• Headache
• Muscle, joint, or bone pain
• Nausea
• Vomiting
• Eye pain (behind the eyes)
• Swollen lymph nodes (glands)
• Rash

Most people recover within a week. However, in some cases, the illness gets worse and can be life-threatening. This is called severe dengue, dengue hemorrhagic fever, or dengue shock syndrome.

Severe dengue happens when the blood vessels become damaged and leak fluid. The body also loses important blood cells called platelets, which help stop bleeding. This can lead to shock, internal bleeding, organ failure, and even death.

Warning signs of severe dengue, a serious medical emergency, can develop quickly. These signs often appear within the first day or two after the fever breaks:

• Severe stomach pain
• Constant vomiting
• Bleeding from the gums or nose
• Blood in the urine, vomit, or stool
• Bruising or bleeding under the skin
• Fast or difficult breathing
• Feeling very tired
• Irritability or restlessness

If you develop these warning signs, it's a medical emergency. Seek immediate medical attention if:

• You've recently been in an area where dengue fever is common.
• You have a fever.
• You have any of the warning signs listed above.

If you've traveled recently and have a fever and mild symptoms that might suggest dengue fever, contact your doctor.

Dengue fever can be serious and even life-threatening. If you've been in an area where dengue is common, and you have a fever, get medical help right away if you notice any of these warning signs: intense stomach pain, throwing up, trouble breathing, or blood in your nose, your mouth (gums), vomit, or bowel movements.

If you've traveled recently and have a fever along with some less severe dengue symptoms, call your doctor. Don't wait. Early treatment is key to avoiding serious problems.

Dengue fever is a disease caused by one of four different viruses. You can't catch it from another person directly. Instead, it's spread by the bite of certain mosquitoes.

Two types of mosquitoes often involved in spreading dengue are commonly found near homes and in areas where people live. If a mosquito bites someone who already has dengue fever, the virus gets into the mosquito. Then, if that infected mosquito bites someone else, the virus is passed on to that person's bloodstream, causing the infection.

Once you recover from dengue fever, you'll be immune to the specific virus that made you sick. However, you won't be immune to the other three types of dengue viruses. This means you could get dengue fever again later in life from a different virus. Importantly, your risk of getting a serious form of dengue fever is higher the more times you've had it. Each subsequent infection increases your chance of a severe illness.

Dengue fever is more likely to happen, or to be more serious, if:

1. You live or visit places with a hot climate. Dengue fever is spread by mosquitoes, and these insects thrive in warm, humid environments. Parts of Southeast Asia, the islands of the western Pacific, Latin America, and Africa are particularly prone to dengue outbreaks, meaning people there have a higher chance of being bitten by infected mosquitoes and getting the disease.

2. You've had dengue before. If you've had dengue fever once, your body's immune system might react differently the next time you're exposed to the virus. This can lead to a more severe form of the disease. Essentially, your body might not fight off the infection as effectively, potentially causing more serious symptoms.

Dengue fever can be serious. A severe case can lead to internal bleeding and harm to organs. Blood pressure can fall very low, potentially causing a dangerous condition called shock. Unfortunately, severe dengue fever can sometimes be fatal.

If a pregnant woman gets dengue fever, there's a chance the virus could be passed to her baby during delivery. Babies born to mothers with dengue during pregnancy also have a higher chance of being born too early (premature), having a low birth weight, or experiencing problems during pregnancy (fetal distress).

Dengue fever vaccines are now available for people aged 6 to 60 in some parts of the world. These vaccines come in a series of shots – either two or three – given over several months. They're only recommended for people who live in areas where dengue fever is common, and who have already had the illness at least once.

Currently, these vaccines aren't available in the main part of the United States. However, in 2019, the U.S. Food and Drug Administration (FDA) approved a vaccine called Dengvaxia for use in children and teens (9-16 years old) who've previously had dengue fever and live in U.S. territories or freely associated states where dengue is widespread.

Crucially, the World Health Organization (WHO) emphasizes that vaccines alone aren't enough to significantly reduce dengue fever in places where it's prevalent. Stopping mosquito bites and controlling mosquito populations are still the most important ways to prevent the disease.

If you live or travel to areas where dengue fever is common, you can take steps to lower your risk of getting bitten by mosquitoes:

• Protect your home: Stay indoors in air-conditioned or screened areas as much as possible. Mosquitoes that spread dengue are most active around dawn and dusk, but they can bite at any time.

• Dress for protection: Wear long-sleeved shirts, long pants, socks, and shoes when you're in areas with mosquitoes.

• Use insect repellent: You can apply permethrin to clothing, shoes, camping gear, or bed nets. Permethrin-treated clothing is also available. For your skin, use a repellent with at least 10% DEET.

• Reduce mosquito breeding grounds: Mosquitoes that carry dengue often breed near homes in standing water, such as old tires, flower pots, pet water dishes, and other containers. You can help reduce mosquito populations by regularly emptying and cleaning any containers that hold standing water. Cover containers of standing water when not in use.

By following these precautions, you can significantly decrease your chances of mosquito bites and, consequently, your risk of getting dengue fever.

Dengue fever can be tricky to diagnose because its symptoms are similar to other illnesses, like chikungunya, Zika, malaria, and typhoid. It's hard to tell them apart just by looking at the symptoms.

To figure out if you have dengue, your doctor will likely ask about your health history and where you've traveled. It's important to give detailed information about any trips outside the country, including the dates and places you visited. Tell your doctor about any mosquito bites you might have gotten while traveling.

Your doctor might also order a blood test to check for the dengue virus. This test is done in a lab to look for signs of the infection.

Unfortunately, there's no specific medicine to cure dengue fever. The best thing to do while recovering is to drink plenty of fluids. This is important because dengue fever can cause dehydration. If you notice any signs of dehydration, such as less frequent urination, no tears, a dry mouth or lips, feeling very tired or confused, or cold, clammy skin, call your doctor right away.

Over-the-counter pain relievers like acetaminophen (like Tylenol) can help with the muscle aches and fever. However, if you have dengue fever, avoid other pain relievers like aspirin, ibuprofen (like Advil or Motrin), and naproxen (like Aleve). These other pain relievers can make bleeding complications more likely in people with dengue fever.

In more serious cases of dengue fever, you might need medical care in a hospital. This could include:

• Supportive care: This means getting the help you need to get better.
• IV fluids and electrolytes: This helps replace lost fluids and salts in your body.
• Blood pressure monitoring: Doctors will check your blood pressure regularly.
• Blood transfusions: If you've lost a lot of blood, a transfusion might be needed.

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