What is Yellow Fever?
Yellow fever is a dengue fever (hemorrhagic) caused by a virus spread by a certain type of mosquito. This virus comes from the Flavivirus genus, which is a large group of RNA viruses.
The yellow fever outbreak is most common in areas of Africa and South America, which affects travelers and local residents. According to the World Health Organization (WHO), there were around 84,000 to 170,000 cases of severe yellow fever with 29,000 to 60,000 deaths in 2003.
In mild cases, yellow fever causes a fever, headache, nausea and vomiting. However, in more serious cases, yellow fever can cause problems related to the heart, liver, and kidney.
Until now, there is no specific treatment for yellow fever. It is recommended that you get the yellow fever vaccine before traveling to endemic areas so that you are protected from the disease.
Causes of Yellow Fever
Yellow fever is caused by a virus spread by the Aedes aegypti mosquito that can breed in and around human habitation. They are dangerous as they can breed in clean water.
Most cases of yellow fever occur in tropical areas such as Africa and South America.
The intermediate mosquito (vector) of yellow fever varies from region to region.
- In the African forest area: Aedes africanus and other Aedes species.
- In South America: Haemagogus and Sabethes
- In the urban areas of Africa and South America: Aedes aegypti.
Humans and monkeys are susceptible to get infected by the yellow fever virus. The Aedes aegypti mosquito transmits the virus between humans, monkeys, or both.
When an intermediate (vector) mosquito bites a human or monkey infected with yellow fever, the virus will enter the mosquito’s bloodstream and circulate before settling in the salivary glands. When an intermediate (vector) mosquito that has been infected bites another human or monkey, the virus will then enter the host – which causes the yellow fever.
When to See a Doctor for Yellow Fever
It may be difficult to diagnose yellow fever, especially in its early stages. More severe cases can be mistaken for other similar illnesses, including malaria, leptospirosis, hepatitis, dengue fever, poisoning and other infections of the Flavivirus genus.
Your doctor may likely ask you a number of questions regarding your medical condition and traveling history.
Polymerase chain reaction (PCR) tests in blood and urine may be required to help detect the virus at an early stage. Then, in the next stage, tests are required to identify antibodies, such as the enzyme-linked immunosorbent assay (ELISA) and the plaque reduction neutralization test (PRNT).
Symptoms of Yellow Fever
The incubation period is the first three to six days after contracting the yellow fever virus. During the incubation period, you will not experience any signs or symptoms.
After that, the infection will enter an acute phase. In some cases, people with yellow fever will enter a toxic phase that can be life-threatening.
You may experience the following symptoms during the acute phase:
- Loss of appetite.
- Nausea, vomiting, or both.
- Sensitivity to light
- Red eyes, face, or tongue.
- Muscle pain, especially in your back and knees
However, the symptoms of acute phase yellow fever usually get better within a few days.
Although the symptoms of yellow fever disappear within one or two days after the acute phase ends, there are some people with a more severe phase, which is the toxic phase.
In this life-threatening phase, acute symptoms reappear and are more fatal. Symptoms of the toxic phase include:
- Liver and kidney failure.
- Slow heart rate (bradycardia).
- Reduced intensity of urination.
- Bleeding from the nose, mouth and eyes.
- Abdominal pain and vomiting, even bleeding.
- Brain dysfunction, including delirium, seizures, and coma.
- Yellowing of the skin and whites of the eyes (jaundice).
Treatment for Yellow Fever
There are no antiviral medications that have been shown to be effective in treating yellow fever. However, you can get supportive care in a hospital, including providing fluids and oxygen, maintaining blood pressure, replacing blood loss, providing dialysis for kidney failure, and treating other infections. Some people receive plasma transfusions to replace blood proteins.
If you have yellow fever, your doctor will likely advise you to stay inside to avoid mosquitoes and to avoid transmitting the disease to other people.
After recovering from yellow fever, you will be immune to this disease for the rest of your life.
Treatment for Yellow Fever
Treatment cost for Yellow Fever depends on the type of treatment recommended by your doctor and the vaccine you receive.
For more details regarding the estimated treatment cost for yellow fever at home and abroad, contact Smarter Health.
Prevention of Yellow Fever
You can prevent yellow fever by getting vaccinations and mosquito protections.
Vaccination is the most effective way to prevent yellow fever. A single dose of vaccine is not only safe and affordable, but also offers lifelong protection against the yellow fever infection.
There are several vaccination strategies to prevent yellow fever and its transmission, such as:
- Immunization for infants
- A mass vaccination campaign in areas affected by yellow fever
- Vaccinate tourists going to areas affected by yellow fever
Below are some criteria for not getting vaccinated, including:
- Infants younger than nine months.
- People who have a severe allergy to egg protein.
- Pregnant women, unless at high risk of infection during a yellow fever outbreak.
- People with immunodeficiency due to symptoms of HIV / AIDS or other causes, including people who have a thymus disorder.
Apart from getting the vaccine, you can help protect yourself against yellow fever by protecting yourself against mosquitoes. In order to avoid mosquito bites, try the following tips:
- Install an air conditioner or close any gaps in your house properly.
- Avoid unnecessary outdoor activities when mosquitoes are most active (i.e. dusk to dawn).
- Wear long-sleeved shirts and trousers when you travel to mosquito-infested areas.
- If your living area does not have adequate curtains or air conditioning, use bed nets for extra protection.
- If your accommodation does not have good window screens or air conditioning, use bed nets. Pre-treated nets with insecticide offer additional protection.
- Apply mosquito repellent containing permethrin on your clothes, shoes and bed nets. Note that permethrin should not be applied on your skin.
- Apple a mosquito repellent lotion that contains DEET’s active ingredients to provide long-lasting skin protection.
Home Remedies for Yellow Fever
Take medications recommended by your doctor to treat yellow fever. Since there is no specific treatment for viral infections, medical treatment for yellow fever focuses on relieving symptoms, such as fever, muscle pain, and dehydration.
To reduce the risk of internal bleeding, avoid medications such as aspirin and other nonsteroidal anti-inflammatory medications.
Consult a doctor immediately if you experience symptoms of yellow fever. Smarter Health can help you make appointments with doctors from hospitals at home and abroad.
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