The top health authority on the Indonesian island of Bali is denying reports in the Australian media of an outbreak of mosquito-borne Japanese Encephalitis (JE).

Bali Health Agency head Ketut Suarjaya said, "There have been no reported cases of JE in Bali since April," when the health authority commenced an island-wide JE vaccination drive targeting more than 960,000 children aged 9 months to 15 years old.  That's the age when children are most vulnerable to the infection.

Most people with the virus don't even exhibit symptoms.  But about one percent can suffer fever, headache, and vomiting; that can progress to serious neurological complications, such as disorientation, seizures, brain swelling.  The end result for these worst-case scenarios include blindness and paralysis.

With this in mind, authorities began the vaccination drive, eventually reaching 101.78 percent coverage.

"The drive also targeted a large number of children with parents who were temporary residents or migrant workers on the island.  That's why the coverage rate is above 100 percent," said Suarjaya.  "I can assure you that the island is not experiencing any disease outbreak at the moment, let alone a JE outbreak," he added.

Warnings to Australian tourists about an alleged JE outbreak on Bali started appearing in NewsCorp outlets last week.