A mumps outbreak in the Marshall Islands may be hitting the country much harder than reported, according to the country's Ministry of Health.
Since the viral disease was first found in the Marshalls in March, there have been more than 1,000 confirmed cases.
The ministry said the number of cases had been dropping in recent weeks, but it was noted this may be due to under-reporting, and officials warn figures could be as high as 3,000.
Our correspondent Giff Johnson said doctors managing the outbreak were saying even though the outbreak could be more widespread than reported, the cases were less serious.
"A very small number of the mumps cases that have been presented. A very small number have been ones that have serious secondary effects and they are pretty happy about that. Because that suggests to them that they have immunisation coverage at least for the children," Giff Johnson.
Giff Johnson said vaccines had been delivered for a mass immunisation program which was being launched for all islands struck by the outbreak.
Marshallese were reported to represent more than half of mumps cases in an outbreak in the US state of Arkansas last year, although there's no clear link with the situation in the Marshalls yet.