Plague Vaccination Vaccination schedule Primary vaccination consists of a series of three shots with the first and second dose given one month apart, and the third dose at the sixth month. Booster doses are given 6-12 months later. The schedule is for persons of age 18 years or above. Data is insufficient for drawing up recommendation for those below age of 18. Recommendations No country requires a vaccination certificate against plague as a condition of entry. The vaccine is normally recommended only for persons with a very high risk of exposure, for instance laboratory workers and field workers working in plague epizootic areas. Travellers to countries reporting plague cases rarely need vaccination, unless the risk of exposure is very high. Even then, a short course of preventive antibiotics with doxycycline during exposure periods is often preferred. Adverse reactions Adverse reactions are quite common, including mild pain, redness, induration at injection sites. More severe headache, tiredness and fever often occur with repeated injections.