Overview
Dengue fever is a mosquito-borne illness that primarily occurs in tropical and subtropical areas of the world. It causes a high fever and flu-like symptoms, such as headache, muscle and joint pain, nausea, vomiting, and a rash. Dengue fever can range from mild to severe, with the severe form known as dengue hemorrhagic fever or dengue shock syndrome potentially leading to shock, internal bleeding, organ failure, and even death. Dengue fever is most common in Southeast Asia, the western Pacific islands, Latin America, and Africa, but it has also spread to new areas, including parts of Europe and the southern United States. Currently, the best ways to prevent infection are to avoid mosquito bites and reduce the mosquito population in affected areas. If you have recently traveled to an area where dengue fever is common and develop a fever and mild symptoms, you should contact your doctor.
Understanding the disease
Symptoms
The symptoms of dengue fever include a high fever (104 F or 40 C), headache, muscle, bone, or joint pain, nausea, vomiting, pain behind the eyes, swollen glands, and a rash. Symptoms usually begin four to 10 days after being bitten by an infected mosquito. Some people may not experience any symptoms, while others may recover within a week or so. However, in severe cases, dengue fever can progress to dengue hemorrhagic fever or dengue shock syndrome, which can cause serious bleeding, shock, organ failure, and death.
Risk Factors
Risk factors for developing dengue fever include living or traveling in tropical and subtropical areas where the virus is prevalent, such as Southeast Asia, the western Pacific islands, Latin America, and Africa. Additionally, having had dengue fever in the past increases the risk of experiencing a more severe form of the disease if contracted again.
Development
Dengue fever develops through the transmission of dengue viruses, primarily by the bite of an infected Aedes mosquito. The virus enters the mosquito when it bites an infected person, and then spreads to other individuals when the same mosquito bites again. Dengue fever has four distinct serotypes (types), and a person who recovers from one serotype gains immunity to that specific type but remains vulnerable to the other three. Repeated infections with different serotypes can increase the risk of developing severe dengue fever, such as dengue hemorrhagic fever or dengue shock syndrome.
Assessment and Diagnosis
Triage
You should see a doctor if dengue fever is suspected, especially if you have recently visited an area where dengue fever is known to occur, you have had a fever, and you develop any of the warning signs. These warning signs include severe stomach pain, persistent vomiting, difficulty breathing, or blood in your nose, gums, vomit or stools. If you have mild symptoms of dengue fever and have recently traveled to an area where the disease is common, it's also a good idea to call your doctor.
Diagnosis
Diagnosing dengue fever can be challenging since its symptoms can be confused with those of other diseases like chikungunya, Zika virus, malaria, and typhoid fever. To diagnose dengue fever, your doctor will generally ask about your medical and travel history, as well as any exposure to mosquitoes. They may also perform a blood test to check for evidence of infection with one of the dengue viruses. It's important to be honest about your travel history and any potential exposure to help with an accurate diagnosis.
Management and Treatment
Complications
Dengue fever can potentially lead to severe dengue, dengue hemorrhagic fever, or dengue shock syndrome. These severe forms of the disease can cause internal bleeding, organ damage, and shock, which can be life-threatening. Dengue fever during pregnancy may also pose risks to the baby, including the possibility of virus transmission during childbirth, pre-term birth, low birth weight, or fetal distress.
Prevention
Preventing mosquito bites and controlling the mosquito population are the primary methods for preventing the spread of dengue fever. In areas where dengue fever is common, the vaccine Dengvaxia is approved for people ages 9 to 45 who have already had dengue fever at least once. The vaccine is given in three doses over the course of 12 months. However, for people who have not had dengue fever in the past (seronegative), receiving the vaccine appears to increase the risk of severe dengue fever and hospitalization due to dengue fever in the future. To reduce the risk of mosquito bites, stay in air-conditioned or well-screened housing, wear protective clothing, and use mosquito repellent containing at least a 10% concentration of DEET.
Preparing for medical consultation
To prepare for an appointment for dengue fever, you should:
- Write down any symptoms you're experiencing, including any that may seem unrelated to dengue fever.
- List your international travel history, with dates and countries visited, as dengue fever is prevalent in certain regions.
- Make a list of all your medications, including any vitamins or supplements you take regularly.
- Be aware of any pre-appointment restrictions and ask your doctor about them when you make the appointment.
- Write down key personal information, such as recent exposure to anyone who's been ill or any other potential sources of infection.
- Prepare a list of questions to ask your doctor, such as:
- What's the most likely cause of my symptoms?
- What kinds of tests do I need?
- What treatments are available?
- How long will it be before I'm feeling better?
- Are there any long-term effects of this illness?
- Do you have any brochures or other printed material that I can take home with me? What websites do you recommend? Remember to bring your vaccination record and a record of any pre-travel vaccinations if possible. Being well prepared will help you make the most of your time with your doctor and ensure a productive appointment.