An outbreak of measles in Zanzibar, where 184 cases have been reported in one district on the island of Pemba since mid-December, has prompted health officials to plan a two-day emergency immunisation campaign beginning on Saturday to curb the disease.

The majority of cases - 166 - were reported in Micheweni District of Pemba in the past two weeks, Sultan Mohamed Mugheiry, Zanzibar's Minister of Health and Social Welfare, told reporters on Thursday. The outbreak is the first on the islands in about five years, Mugheiry said.

"The situation is not good. We have had one death and we have been receiving an average of five cases a day, including some adults," said Abdulhamid Ameir Salum, the manager of Zanzibar's Expanded Programme on Immunisation.

A house-to-house awareness campaign is under way. The campaign is supported by the United Nations Children's Fund (UNICEF) and targets 44,653 children aged between six months and 15 years in Micheweni District.

Salum attributed the latest measles outbreak to frequent travel between the islands and mainland Tanzania, especially Dar es Salaam, where measles is more common.

"Another reason for the outbreak is reluctance by parents to bring their children to health centres for vaccination and failure to respond to immunisation campaigns," Salum said.

According to the UN World Health Organization, measles is a major killer of young children, despite the availability of a safe and effective vaccine for the past 40 years. Measles is an acute viral respiratory illness associated with high fever, rashes and vomiting.