Yellow fever: what is it, how dangerous is it, how do you get it, and should you vaccinate?

What is yellow fever?

• Yellow fever is an infectious disease caused by a virus transmitted by mosquitoes.
• The disease owes its name to the characteristic yellowish skin of sick people.
• Some mosquitoes can cause the disease by biting human skin, transmitting it via the lymphatic system. This compromises the human immune system to the point of causing a life-threatening situation.

Where does yellow fever occur?

• The mosquitoes that transmit yellow fever are primarily found in Africa and South America.
• There is an increased risk in Africa from Sub-Saharan Africa to the Namibian-Mozambican border and in and around the Amazon region of South America.
• The mosquitoes bite during the day and are mainly found in rural areas.
• An epidemic can break out if an infected person travels to a densely populated area. However, the disease is not directly transmitted from person to person.

What are the symptoms of yellow fever?

• The first symptoms appear three to six days after infection with the yellow fever virus.
• Some common symptoms include: sudden fever, chills, headache, back pain, muscle aches all over the body, nausea, and vomiting.
• The fever usually subsides within four to five days. During this time, symptoms such as pain behind the eyes, red eyes, muscle aches, joint pain, and facial redness typically occur.
• After the initial phase, the disease appears to recover for a short time, but in some cases, a second fever attack follows, with the skin turning yellow. Bleeding, such as bleeding gums and blood in vomit and stool, may occur at this point.
• In severe cases, the disease can lead to coma and death.

Can yellow fever be treated?

• Once infected, there is no treatment for the yellow fever virus.
• The only treatment is pain management and ensuring people stay cool and drink plenty of water.
• Headaches are relieved with painkillers, and fever is controlled with antipyretics. In some cases, a blood transfusion is necessary.
• In areas with high mosquito populations, patients are usually cared for under a mosquito net to prevent further spread of the infection by mosquitoes.

Are there vaccinations against yellow fever?

• Yellow fever is easily prevented by vaccination with a safe and effective vaccine.
• Officially, the vaccination is valid for 10 years. However, the protection provided by the yellow fever vaccination lasts much longer, likely lifelong.
• People staying in or traveling to areas with a high risk of yellow fever are advised to get vaccinated.
• A number of countries require the yellow fever vaccination. Yellow fever will be present in some countries, but in many cases, it is a preventative measure if you are traveling from a country where yellow fever is present.
• When traveling to a country that requires vaccination, you must be vaccinated at least 10 days before arrival.

How can you prevent yellow fever?

• Getting vaccinated is the most effective measure to prevent yellow fever.
• Be careful not to get bitten by mosquitoes! In areas where yellow fever is prevalent, mosquitoes transmit several nasty diseases.
• It is advisable to wear protective clothing that covers your arms and legs and to apply mosquito repellent containing DEET. Air conditioning and window screens also offer partial protection.
• Outside of cities, it is important to bring mosquito nets or mosquito repellent.