While the rest of the world panics about bird flu, the islands of Mauritius, Réunion and the Seychelles in the Indian Ocean are in the grip of a mosquito-borne epidemic that has infected thousands and killed at least 78 in a month.

Madagascar has recorded the first cases of the mosquito-borne disease Chikungunya, which has caused havoc and is suspected in 93 deaths on nearby Reunion Island.

Reunion is about 500 miles (800km) east of Madagascar in the Indian Ocean and the presence of the infection on Madagascar puts 18 million inhabitants at risk.

The French prime minister, Dominique de Villepin, has declared a state of emergency on Réunion, where 157,000 people, one in five of the population, have been affected by the disease.

De Villepin, has returned from Réunion, and although his trip lasted only 24 hours, it was long enough for the premier to be bitten by a mosquito and there are fears he himself may have fallen victim to the mosquito-borne disease.

Mr de Villepin has announced a £60 million aid package to fight the epidemic of the disease.

A quarter of Réunion’s 770,000 inhabitants have been infected - most of them in the past two months.

The Chikungunya virus broke out on Réunion a year ago and to date the disease, for which there is no vaccine or cure, has reached Mauritius, where 1,174 have been stricken, and the Seychelles, where more than 1,000 are infected.

The symptoms of Chikungunya include high fever, dehydration, nausea and severe joint and bone pains; there is no known cure, but sufferers usually recover after several days.

Experts say that although the disease is generally non-fatal, it can leave patients vulnerable to other life-threatening diseases.

The island’s tourism industry has been badly hit by the epidemic.

The mosquito that spreads the disease, Aedes albopictus or Asian tiger mosquito, is prevalent in parts of the Mediterranean, and scientists say there is a possibility of a European outbreak this summer.