Some 1,300 cases of the pneumonic plague, which is transmitted by air, have now been confirmed.
An estimated 50 million lives were lost as a result of the Black Death epidemic of the 1300s.
And now the deadly disease has spread into more African countries after taking root in Madagascar.
Countries affected include South Africa, Mozambique, Tanzania, Kenya, Ethiopia, Comoros, the Seychelles, Mauritius and Reunion.
So far, the virus has killed 124 people and infected around 1,300, but scientists say this figure will definitely rise.
The World Health Organisation, which has been working with Madagascar’s Ministry of Health, has warned the risk of the epidemic spreading is “high”.
"Plague, though terrifying, is nothing new in Madagascar, where about 600 cases are reported annually," the organisation said on its website.
But officials said while "health officials couldn't explain it", the plague is different this time.
A Crisis Emergency Committee has been established in response to the outbreak, which will "coordinate surveillance, contact tracing, case management, isolation and supplies" until it is contained.
Air Seychelles, one of Madagascar's biggest airlines, stopped flying earlier in the month, in an effort to contain the spread and airports are screening passengers to avoid spread of the plague.
Schools and businesses have been closed, and large public gatherings have been cancelled. READ MORE
