Two cases of meningococcal meningitis have been confirmed at Rarotonga Hospital.
But health authorities in the Cook Islands say there are no fears of a widespread outbreak.
The Director of Clinical Services, Dr Henry Tikaka, says both cases are recovering well.
Dr Tikaka says all doctors on Rarotonga and the outer islands have been informed of the cases and warned to watch out for anyone with possible symptoms.
The authorities have also confirmed that the hospital is treating a case of TB.
The patient is said to be from the outer islands and those who had been in contact with him have also been treated.