Yellow fever is a disease that spreads to people through bites from infected mosquitos. It is found in tropical regions of South America and Africa.
The most recent outbreaks of yellow fever and the highest risk of illness have been recorded in Nigeria and Brazil, with Brazil having an ongoing outbreak.
The virus causes flu-like symptoms that include fever, chills, nausea, vomiting, gas, and indigestion. The yellow fever virus is one of the small RNA viruses that are classified in the family Flaviviridae.
The virus is transmitted among humans and mosquitoes but also among other primates and mosquitoes. Infected people can also transmit the virus to other mosquitoes when they are bitten.
People traveling to these areas are at greater risk of catching the yellow fever virus and becoming ill. You are also at higher risk if you stay in rural areas or in forested regions where yellow fever is present, and if you are outside at dawn and dusk when mosquitoes are most active.
The best way to prevent getting yellow fever is to get vaccinated if you plan to travel to an area where the illness is known to occur.
Vaccination is recommended for people older than 9 months and younger than 60 years. However, pregnant women, people older than 60 years, and those with a weak immune system should not get the vaccine.
You can also wear long-sleeved clothing and use bug repellent to try to prevent being bitten by mosquitoes. If possible you should also avoid being active when mosquitoes are most active.
The vaccine is effective especially if taken a month before traveling, and it gives you protection for life.
Some countries may require proof of vaccination before you are allowed into the country, which is something you should check if you plan to travel to a high-risk country.
The South American countries where yellow fever vaccination is strongly recommended by the CDC include Columbia, Venezuela, French Guiana, Guyana, Suriname, Peru, Bolivia, Ecuador, Paraguay, and Brazil.
Only certain species of mosquitoes can carry the yellow fever virus and transmit the disease to people. The most well-known and most common vectors of the yellow fever disease are the mosquitoes Aedes aegypti and Haemagogus species.
Vaccination is also recommended if you are visiting western and central regions of Africa including Guinea, Sierra Leone, Togo, Ghana, Burkina Faso, Cote d’Ivoire, Liberia, Senegal, Gambia, Cameroon, Nigeria, Central African Republic, Democratic Republic of Congo, Rwanda, Burundi, Uganda, Kenya, Angola, Gabon, Republic of Congo, and Sudan.
There is no way to kill the virus if you contract the disease. Doctors can only treat the symptoms and give supportive care. Half of the people who contract Yellow Fever die.
It is therefore important to be aware of the illness and take steps to avoid infection.