Yellow Fever: Causes, Signs, Prevention and Treatment

 

Yellow fever is a very serious, potentially fatal, mosquito-borne disease caused by the flavivirus. The disease is transmitted to man by infected species of Aedes mosquitoes. The mosquito becomes infected when it bites an infected human or animal (especially a primate).The disease is commonly seen parts of Africa and tropical South America. Severe cases of yellow fever can cause high fever, internal bleeding and liver and kidney damage. Often, liver damage leads to severe jaundice, which causes yellowing of the skin and eyes and is therefore known as yellow fever.Since yellow fever is associated with acute hemorrhage, you should contact your family doctor or general practitioner immediately if symptoms consistent with those of you or a family member appear, to avoid fatal consequences.

How does Yellow Fever Develop?

The flavivirus, which causes yellow fever, enters the system of a mosquito, multiplies in its body and spreads to its salivary glands. Soon after, when the mosquito nourishes a person, the virus is transmitted to the person. It travels through its body and spreads to various glands in the body. when the virus enters the bloodstream, it causes inflammation of the blood vessels thereby making them to swell and leak. This affects the blood flow in the body and can cause the body to go into shock because the organs are not getting the required amount of oxygen-rich blood.The incubation period of the flavivirus in humans varies between 3 and 6 days. After that there is a sudden onset of chills, fever, muscle and joint pains and headaches. After a day or so, other symptoms may appear soon, including facials, redness, deep red tongue, loss of appetite, and tremors. These symptoms persist for 3 to 4 days and disappear in most cases.  
 The patient starts to improveHowever, a small percentage of patients (15% to 25%) see a return of fever after about 24 hours of recovery from initial symptoms and develop jaundice and hemorrhagic symptoms. Abdominal pain occurs along with vomiting. They can also bleed from the mouth, nose or eyes. 50% of patients entering the toxic phase die within 7 to 10 days.People who have suffered from yellow fever and have recovered will be immune to the disease for the rest of their lives.There is no cure for yellow fever, but it can be prevented by vaccination. However, not everyone is suitable for the yellow fever vaccine. The exceptions include:

Infants aged 6-8 months
People with a severe allergy to any part of the vaccine, including eggs, egg white or gelatin
People who had a severe reaction to a previous dose of yellow fever vaccine
People HIV / AIDS or another disease that affects the immune system
People with a weak immune system due to cancer or other diseases
People with thymus disorder
Adults 60 years and older
pregnant women and breastfeeding mothers

What are the symptoms of yellow fever? How is yellow fever diagnosed?The symptoms of yellow fever occur three to six days after exposure to the virus. It develops faster than dengue, malaria or chikungunya.The initial symptoms at the onset of this disease are the same as those of ordinary flu and include:

• a headache
• Muscle and joint pain
• chills
• high fever

The second phase of this fever is an acute phase and the symptoms that appear in addition to the above are:

• flush
• Tremble
• back pain
• nausea
• loss of appetite

After this phase, most patients recover. However, 15% to 25% of patients find a third phase that represents the toxic phase and can often be fatal. Before this phase, the symptoms of the second phase disappear for a period of about 24 hours. They then appear with new serious conditions such as:

• reduced urination due to kidney damage
• stomach pain
• Vomiting (sometimes with blood)
• internal bleeding (hemorrhage)
• Jaundice (liver damage), which causes yellowing of the skin and eyes
• Hepatitis (inflammation of the liver)
• Heart rhythm problems
• seizures
• delirium
• bleed from the nose, mouth and eyes 
• multiple organ failure
  

According to World Health Organization statistics, 50% of patients who reach the third phase die while the other half recover.

Diagnosis

Diagnosis of yellow fever can be a complicated process due to the fact that the symptoms can be adapted to a variety of other diseases, such as flu, severe malaria, typhoid fever, leptospirosis or viral hepatitis.A general practitioner will usually examine your symptoms and ask if you recently traveled to a place where yellow fever is active.A special blood test, performed solely to diagnose yellow fever, can produce specific antibodies that are virus-specific in response to the particular infection. Additional specific antibody tests, such as the Plaque Reduction Neutralization Test (PRNT), are being conducted to confirm yellow fever diagnosis.

What are the complications of yellow fever?

The complications of yellow fever can be very severe and often lead to death. Some of them include:jaundice, internal bleeding (hemorrhage). Heart rhythm problems, seizures, delirium, coma bleed from the nose, mouth and eyes, multiple organ failure

What is the Treatment of Yellow Fever?

There are no specific medications for the treatment of yellow fever. At the most, they are treated inpatient and receive supportive measures such as the provision of fluids, oxygen on demand, replacement of blood loss, dialysis of kidney failure, and the treatment of other complications, if any. The treatment focuses more on alleviating yellow fever symptoms such as dehydration, bleeding or bleeding, muscle and joint pain and so on.Depending on your condition, you may be quarantined. And if you are treated at home, the doctor will ask you to protect yourself from mosquito bite
to others.