The plague has claimed 128 lives on the African island of Madagascar and prompted nine countries nearby to be issued with a health alert.
Destinations popular with British tourists – including Mauritius, Kenya, and the Seychelles – could now be under threat.
At least 140,000 British tourists travel to Mauritius every year on holiday.
And, at least 100,000 British residents visit Kenya and the Seychelles each year.
A spokesman for the Foreign Office warned: “There is currently an outbreak of pneumonic and bubonic plague in Madagascar.
“Outbreaks of plague tend to be seasonal and occur mainly during the rainy season with around 500 cases reported annually.”
The government has suspended flights from Madagascar to the Seychelles in a bid to stop any further spread of the disease.
The World Health Organisation said: ‘The risk of the disease spreading is high at national level… because it is present in several towns and this is just the start of the outbreak.”
International agencies have sent over one million doses of antibiotics to Madagascar.
More than 1,130 people are thought to have been infected by the outbreak.
It has forced the closure of schools, universities and a ban on public gatherings in Madagascar.
The current outbreak is unusual as it has affected urban areas increasing the risk of transmission, according to WHO.
Health experts said that the plague bacteria develops in rats and is carried by fleas.
In humans, the pneumonic version is transferred through coughing and can be fatal within 72 hours.
Most of the victims recorded in Madagascar have been infected with the pneumonic form. The bubonic form is less dangerous.
Both plagues can be cured using antibiotics if given quickly.