- 1. When to get the vaccine?
- 2. What reactions can occur to the yellow fever vaccine?
- 3. What are the symptoms and when do they appear?
- 4. What is the relationship between yellow fever and monkeys?
- 5. Does yellow fever pass from one person to another?
- 6. Why does the skin turn yellow?
- 7. What is the difference between dengue and yellow fever?
- 8. How is the treatment done?
- 9. What is the difference between wild and urban yellow fever?
- 10. When can the yellow fever vaccine fail?
Yellow fever is a serious infectious disease that can be transmitted by the bite of two types of mosquitoes, Aedes Aegypti or Haemagogus Sabethes . This disease causes symptoms such as abdominal pain, headache and fever and must be treated in order to alleviate the symptoms.
Here are the 10 most common doubts regarding this disease:
1. When to get the vaccine?
The yellow fever vaccine is indicated for all people living in areas at risk, such as the northern region of Brazil and some countries in Africa, but it must also be taken by people who intend to travel to these places, who work with rural tourism or who need to enter the forest in these regions and who have never been vaccinated.
The vaccine can be taken 10 days before travel to areas at risk of disease transmission, such as Brazil and Africa, and can be applied from 9 months of life. The vaccine is contraindicated for pregnant women, immunosuppressed, who are individuals with weakened immune systems, and people allergic to egg yolk. More information at: Yellow fever vaccine.
In 2018, the fractional vaccine, which contains 1/10 of the full vaccine dose and protects for 8 years, was also released. This measure is implemented when there is an epidemic of the disease to allow more people to be vaccinated.
Know who can't get the yellow fever vaccine.
2. What reactions can occur to the yellow fever vaccine?
Reactions to the vaccine are rare, but side effects such as skin rash, muscle pain, seizure, headache, fever, and general malaise can arise. The injection site is usually painful, but placing a small piece of ice on the site, giving a gentle massage helps to relieve this discomfort.
3. What are the symptoms and when do they appear?
Symptoms of yellow fever include fever, headache, chills, nausea, vomiting, aches in the body, yellowed skin and eyes and there may be bleeding from the gums and nose, dark stools and bloody urine. These symptoms appear between 3 and 7 days after being bitten by the mosquito. Learn more at Yellow fever symptoms.
In the most severe cases, symptoms such as heart problems, kidney and liver disease and bleeding may appear. In severe forms, if the person does not receive medical assistance, he or she may die and must therefore stay in the hospital to receive treatment.
4. What is the relationship between yellow fever and monkeys?
Gibão monkeys, which are very common in Brazil, are frequently affected by the yellow fever virus. Thus, when the virus is circulating in your blood and it is bitten by the Haemagogus Sabethes mosquito , it becomes infected and transmits the disease by biting humans.
5. Does yellow fever pass from one person to another?
Yellow fever is not transmitted from individual to individual, as it is only transmitted by infected mosquitoes.
6. Why does the skin turn yellow?
The skin turns yellow because the virus affects the liver, preventing blood clotting factors from forming and increasing the amount of bilirubin in the blood. As this bilirubin is yellow, its accumulation in the skin and eyes causes them to turn yellow.
7. What is the difference between dengue and yellow fever?
Dengue and yellow fever are caused by different viruses, so dengue is only transmitted by Aedes Aegypti , while yellow fever can be transmitted by Aedes Aegypti or Haemagogus Sabethes mosquitoes.
In addition, the first symptoms of yellow fever are usually fever, vomiting and back pain, while the first signs of dengue include joint pain, red spots on the skin, diarrhea and general tiredness. Both diseases can be prevented through vaccination and protective measures, such as the use of repellents.
8. How is the treatment done?
The treatment for yellow fever consists only in relieving the symptoms that the disease causes through analgesic and antipyretic drugs that do not contain acetylsalicylic acid, which could lead to the patient's death, and requires hospitalization to prevent the disease from progressing to more severe cases.
9. What is the difference between wild and urban yellow fever?
There are two types of yellow fever:
- Yellow wild fever: It is transmitted by the bite of the Haemagogus Sabethes mosquito , which bites the Gibbon monkey, which often has the virus circulating in the blood, and then bites the man; Urban yellow fever: It is transmitted by the bite of the mosquito Aedes aegypti , the same that transmits dengue, but there are no cases registered in Brazil since 1940.
This indicates that there have been no cases of urban yellow fever in the country for more than 70 years, and all registered cases are yellow fever of the wild type.
10. When can the yellow fever vaccine fail?
Despite being rare, the yellow fever vaccine can fail and it can happen by reaction or because the vaccine did not work.
The reaction happens when the vaccine activates the immune system with a weakened virus, that is, it causes the person to develop a picture similar to that of the disease. Because of this possibility of reacting to the vaccine, it is not recommended for people over 60 or with diseases that compromise the immune system to take it without medical advice.
Another case that characterizes the failure of the vaccine is when the vaccine does not activate the immune system, which may be because of the immunity of the person who was very low at the time of the vaccine, because of a pre-existing infection with the same virus present in the vaccine or because the vaccine was taken when there was an infection developing in the person (incubation period).
