``Lions are dying like flies,'' Johan Krige, a deputy director in the Department of Agriculture, said in the Sunday Times newspaper.

Krige said the entire lion population of the park could be wiped out in five to 10 years if the disease was allowed to spread unchecked.

There are well over 1,000 lions in the park, according to a park official. More than 90 percent of lions tested in the southern quarter of the reserve, the area most popular with tourists, were infected and scientists predicted most would die, the newspaper said, quoting a recent study.

Lions have no natural resistance to the disease, spread by herds of infected buffalo, the study by academics said. South Africa may have to ask for international help in fighting the disease, which could have a``devastating'' impact on the country's tourism industry, Deputy Tourism Minister Peter Mokaba said.