Infection A day-biting mosquito transmits yellow fever. In forest areas monkeys may be a reservoir. The risk of infection is small, but the infection serious.
Vaccination certificate Yellow fever is the only disease still subject to international rules concerning vaccination requirement for international travel. The countries, which have yellow fever, are marked on the map below. These countries has the right to request a valid yellow fever vaccination certificate upon entry. Some countries, where there is no yellow fever, but where there is a risk of introducing yellow fever, can also request a valid vaccination certificate if you arrive from a country with yellow fever. The certificate is valid 10 days after the vaccination and for 10 years thereafter. The WHO recommends that all travellers to countries with yellow fever be vaccinated. Countries with yellow fever, can requst a valid vacciation certificate from travellers, and countries without yellow fever can request a certificate from travellers entering from a country whith yellow fever.
There is an effective, live (attenuated) vaccine.
The vaccine protect for 10 years after one injection.
Because the vaccine is a live virus, persons with compromised immune systems should not be vaccinated.
Persons over 60 years, who has not previously been vaccinated probably has an increased risk of complications.
Pregnant women and children under 9 months of age should not be vaccinated.
The vaccine contain small amounts of egg proteins, and person with an allergy to egg should not be vaccinated.
Symptoms Yellow fever is hepatitis with fever, jaundice and bleedings. The lethality is usually between 5% and 40%.
Diagnosis Antibodies and sometimes virus nucleic acid can be detected in a blood sample.
Treatment Supportive only. No specific antiviral drugs available.
More about yellow fever Yellow fever often occurs in small epidemics. The local population is usually vaccinated and with a reservoir in monkeys it is impossible to predict where the non-vaccinated traveller are at risk. Tourists, who is not vaccinated, die every year from yellow fever.