Anyone in the Cook Islands who has problems with eye irritation or breathing difficulties is being asked to report their symptoms to a newly set up hotline.
The service has been introduced after a series of health problems became prevalent in Titikaveka.
People who experience sore, watery eyes, breathing difficulties or nose irritation, are asked to report the symptoms immediately to Rarotonga hospital.
Once a reported case of the irritant syndrome is confirmed, the hospital will notify investigators to take samples.
The cause of the irritant syndrome is not known, but a flyer being distributed to households says there are two main possibilities for the syndrome - ground level ozone from the burning of leaves and car exhaust, and/or air-borne toxic algal blooms.
The first reported case of the syndrome affected students at Titikaveka College in November last year.