Plague is one of the three diseases for which international quarantine is obligatory, the others being cholera and yellow fever. Cases must be notified. All patients with plague, irrespective of the presence of cough or pneumonia, should be treated in strict isolation for at least 48 hours (risk of secondary pneumonic plague with subsequent aerogenic transmission). The room should be decontaminated and sprayed with insecticides. Masks, goggles and protective clothing are indicated. Gloves should be worn when handling bubonic aspirates and blood. Contacts may take tetracyclines (4 x 500 mg) or vibramycin for 1 week (sulphonamides are an alternative). They should be closely monitored for 7-10 days.

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Vaccination gives temporary protection against bubonic plague, but the vaccine is not easy to obtain. It is only indicated in very specific situations. Soldiers in the American forces during the Vietnam War were routinely vaccinated with a dead cell vaccine (3 primary injections followed by boosters, depending on the antibody titre in the blood). There was a much lower incidence in vaccinees than in the South Vietnamese forces (1/3000 cases per year of exposure).

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Urban plague can usually be controlled by quarantine and by rat control and flea eradication. Sylvatic plague cannot definitively be eradicated in view of its animal reservoir. In combating urban plague, fleas should be controlled first and then the rats. Otherwise a large number of fleas are suddenly released (since they no longer have any animal host) and then transfer to humans. It is important to have an idea of the susceptibility of the insects to various insecticides. Thus, strains of Xenopsylla cheopsis and Synosyllus fonquerniei (flea vectors in Madagascar) have been found which were resistant to the insecticides DDT and dieldrin (organochlorine compounds), malathion or phenitrothion (organophosphates) and propoxur (carbamate). Such resistance data are useful if there is an outbreak. Rat control involves the use of various methods, including rodenticides such as anticoagulants (warfarin, fumarin, bromadiolone, chlorophacinone), zinc phosphide, sodium fluoroacetate and strychnine. Rats are very social and intelligent animals and can learn to avoid poison, as well as teaching their nest mates to do so.