Health officials on Tanzania's semi-autonomous island of Zanzibar have reported a resurgence of measles, a disease once thought eradicated from the area.

"We had controlled measles in the islands; unfortunately, we have had 18 cases now," Sultan Mohamed Mugheiry, Zanzibar’s Minister of Health and Social Welfare, said on Wednesday.

According to health professionals, measles is highly contagious and causes fever, rash, and flu-like symptoms. The telltale rash can also be accompanied by diarrhoea and more serious conditions, including pneumonia and inflammation of the brain.

The World Health Organization (WHO) estimates that about 450,000 people worldwide, mostly children, die from measles each year.

An official from the Health Ministry's Immunization Department, Abdulhamid Ameir Saleh, attributed the latest measles outbreak to people on the island mingling with people on the Tanzanian mainland, specifically in the commercial capital of Dar es Salaam, where measles has been a problem.

"Another reason for the outbreak is negligence by parents to bring their children to health centres for treatment and to respond to immunisation campaigns," Ameir said.

Ameir said his department had launched an awareness campaign, urging parents who travel with children to report to health centres for screening and treatment, and "to make sure their children receive immunisation".

The measles cases have been identified at the Zanzibar Mnazi Mmoja national hospital and at health centres in the rural areas of Kivunge, Mwera and Kidoti on Unguja Island, and at Micheweni in Pemba. The isles of Unguja and Pemba, with estimated populations of one million, make up Zanzibar.

Ameir warned that the measles outbreak could spread quickly if the public failed to observe health precautions, including immunisation