Yellow Fever

Background of Illness

Yellow Fever is a viral illness spread by mosquitos, it occurs in Africa and South America, however it has been reported in Asia. Symptoms range from non specific temperature, achy, photophobia and headache leading to sickness which ends up in jaundice and haemorrhage. Mortality rate is 5-20% in the local population, however this fatality can exceed 50% in the non-immune travellers. There is no specific treatment for yellow fever so preventative measures, for example medication of the mosquito, avoiding mosquito bites and immunisation reduces the risk.

Vaccine Facts

The vaccine is a live vaccine, the single dose confirms protection for up to 10 years given as a one injection into the subcutaneous, under the skin in the shoulder, reinforcing dose is given after 10 years. Yellow Fever certificate is required as a pre-requisite for entry into certain countries. The certificate is valid for 10 years beginning from the 10th day after injection immediately after re-immunisation.

Complications

It is contraindicated in under five months, those who have had anaphylactic reaction to the previous dose and those who have had confirmed anaphylactic reaction to egg and those with thymus gland disorders and the patients with the above condition should be warned about risks of yellow fever and should take measures to avoid mosquito bites. The yellow fever vaccine is only given at designated yellow fever vaccination centres, yellow fever vaccination should not be given to pregnant women, but there is no evidence of any harm to the baby from vaccination after breast feeding mothers. Adverse reactions following yellow fever vaccination are very mild, consist of muscle ache, headache etc. 1 in 10,000 people have been reported to have post vaccine encephalitis, however this compared to contracting yellow fever illness is very rare. The vaccine is associated adverse effect is multi organ failure, which resembles yellow fever, this is more common in older people over the age of 60. The risks associated with the vaccine can increase several fold and patients should be counselled regarding this.