Yellow Fever
£75.00
- Eligible patients: 9 months and above
- The vaccine schedule: 1 dose
- Length of protection: Lifetime Vaccine (at least 35 years).
- Certificate included
- Yellow fever (YF) is caused by a virus of the Flaviviridaefamily, which circulates between infected monkeys or humans and mosquitoes.
- YF virus can cause an illness that results in jaundice (yellowing of the skin and eyes) and bleeding with severe damage to the major organs (e.g. liver, kidneys and heart). The mortality rate is high in those who develop severe disease.
- YF is a vaccine preventable disease. In order to prevent the international spread of YF, under the International Health Regulations (IHR) (2005), countries may require proof of vaccination, recorded in an International Certificate of Vaccination or Prophylaxis (ICVP). A Medical Letter of Exemption (MLoE) from vaccination which should be taken into consideration by a receiving country can be provided where a health professional advises that an individual should not be vaccinated on medical grounds.
- Areas with a ‘risk of YF transmission’ (also known as endemic areas) are countries (or areas within countries) where mosquito species known to transmit the disease are present and where the infection is reported in monkeys and/or humans.
- Some areas are designated as ‘low risk’ (also described as areas with low potential for exposure to yellow fever); these are bordering endemic areas where there have been no confirmed reports of yellow fever in either monkeys or humans, and evidence of transmission in the past is uncertain or suggests low prevalence of infection. Transmission of YF virus in these areas is therefore considered unlikely.
- Under-reporting, limitations in surveillance methods and misdiagnosis make estimating the burden of YF disease challenging. The World Health Organization (WHO) estimates 200,000 cases of YF and 30,000 deaths occur globally each year with the majority (90 percent) occurring in Africa. These estimates are based on studies from the early 1990s. However, a recent study of YF disease burden in Africa estimated there to be 130,000 (95% CI 51-380,000) cases of severe YF in 2013, resulting in 78,000 (95% CI 19-180,000) deaths.
- YF varies in severity. The infection has an incubation period (time from infected mosquito feeding and symptoms developing) of three to six days. Initial symptoms include myalgia (muscle pain), pyrexia (high temperature), headache, anorexia (lack of appetite), nausea, and vomiting. In many patients there will be improvement in symptoms and gradual recovery three to four days after the onset of symptoms.
- Within 24 hours of an apparent recovery, 15 to 25 percent of patients progress to a more serious illness. This takes the form of an acute haemorrhagic fever, in which there may be bleeding from the mouth, eyes, ears, and stomach, pronounced jaundice (yellowing of the skin, from which the disease gets its name), and renal (kidney) damage. The patient develops shock and there is deterioration of major organ function; 20 to 50 percent of patients who develop this form of the disease do not survive [21]. Infection results in lifelong immunity in those who recover.