Prevention and control measures for yellow fever

Prevention measures

A safe, effective and inexpensive yellow fever attenuated vaccine, known as YF 17D, has been used for more than half a century. The vaccine is highly effective but routine vaccination is implemented by very few countries.

A YF vaccination certificate is the only vaccination certificate that should be required in international travel. The certificate of vaccination against yellow fever is valid for the life of the person vaccinated, beginning 10 days after the date of vaccination. An individual risk benefit analysis particularly in patients with auto-immune diseases, immune-deficiencies or other related underlying conditions, and also among the elderly should be conducted prior to vaccination taking into account the destination and duration of travel, and the likelihood of exposure to mosquitoes.

At the beginning of the 20th century, urban YF was eliminated from many countries by energetic campaigns to eliminate Ae. aegypti breeding sites. After World War II, targeted application of DDT to infested containers and their surroundings was an outstanding success. According to the Pan American Health Organization, the species was eradicated from 22 countries of the Americas. No substitute for DDT is currently available. Many health authorities resort to insecticidal aerosols delivered from hand-held machines, road vehicles or aircraft. The technique is expensive and ineffective. Moreover, even if a high kill rate were attainable, the impact on adult populations would probably be too short to make an effective impact on transmission. The World Health Organization has recommended ‘community based source reduction’ for several years, but there is no evidence that this has been successful anywhere in the world.