Travel Health; Yellow Fever
Yellow fever is a viral infection that is spread by the bite of an infected Aedes aegypti mosquito which mainly bites during daylight hours. It's found in parts of Africa, South America, Central America and the Caribbean. Infection with yellow fever results in lifelong natural immunity in individuals who recover. Up to 60% of those infected with yellow fever will die from the disease as there is no treatment available. There's a vaccine that can stop you from getting it if you're travelling to an area where the infection is found.
Yellow fever vaccination is carried out for two different purposes:
- To prevent the international spread of the disease by protecting countries from the risk of importing or spreading yellow fever virus. The countries that require proof of vaccination are those where the disease may or may not occur and where the mosquito and potential non-human primate hosts of yellow fever are present. Any importation of the virus by an infected traveller could result in its propagation and establishment, leading to a permanent risk of infection for the human population.
- To protect individual travellers who may be exposed to yellow fever infection. As yellow fever is frequently fatal for those who have not been vaccinated, vaccination is recommended for all travellers (with a few exceptions) visiting areas where there is a risk of yellow fever transmission. An individual risk assessment is indicated for all travellers.
You need to have the vaccine at least 10 days before travelling to give it enough time to work. Your certificate will only be valid after this time. The vaccine and certificate are only available from registered yellow fever vaccination centres. It is not usually available on the NHS and must be administered by a private clinic.
The yellow fever vaccine provides lifelong protection for most people. Booster doses and new vaccination certificates used to be recommended every 10 years for people who continued to be at risk of the infection, but this is no longer necessary in most cases. All vaccination certificates are now valid for life, including older ones with an expiry date on them.
The yellow fever vaccine can cause some side effects, but the risk of not being vaccinated usually outweighs the risk of having side effects.
After having the vaccine, up to one in every three people gets:
- a headache
- muscle pain
- a mild fever
- soreness at the injection site
These side effects usually pass within two weeks.
There are also some more serious but very rare side effects that can occur, including an allergic reaction and problems affecting the brain or organs. These occur less than 10 times for every million doses of vaccine given.
However, in some circumstances, the yellow fever vaccine isn't always recommended for some people, including:
- babies under nine months of age – babies who are six to nine months old may sometimes be vaccinated if the risk of getting yellow fever is high
- pregnant and breastfeeding women
- people over the age of 60
- people with weakened immune systems – such as those with HIV
- people who are very allergic to any of the ingredients in the vaccine – including people with an egg allergy
If you have visited an area with yellow fever and develop symptoms, you must see a doctor as soon as possible. The first symptoms of yellow fever usually develop three to six days after being infected.
- a high temperature (fever) of 38C (100.4F) or above
- a headache
- feeling sick or vomiting
- muscle pain and backache
- your eyes being sensitive to light
- loss of appetite and feeling generally unwell
Most people make a full recovery after three or four days. A few people go on to get more serious symptoms, such as:
- yellowing of the skin and eyes (jaundice)
- bleeding from the mouth, nose or eyes
- vomitting blood or blood in poo
Up to half of those who get these symptoms die. See a doctor straight away if you get symptoms of yellow fever while travelling in an area where the infection is found.
Take on messages from today’s blog:
- Vaccination against yellow fever is extremely important and mandatory in some cases if you are visiting risky areas and can be the best way to protect yourself against the infection.
- It is important to be precautious and follow travel advice even if you are vaccinated.
For more information on vaccinations, call our travel health clinic at 0203 630 1244.