The United Nations World Health Organization (WHO) has dispatched a team of experts to Angola to help local authorities probe an outbreak of a mysterious but apparently non-fatal illness afflicting schoolchildren in the African nation.

The illness has been reported in schools in the capital, Luanda, and in other Angolan provinces, WHO reported today. Sufferers have experienced vomiting, headaches, sore throats, eye irritation, coughing, breathing difficulties and, in some cases, fainting.

No deaths have been reported so far and the symptoms often stop within a few hours of the illness first striking.

In a statement WHO said that "although the cause of these outbreaks still remains unknown, this may be related to exposure to irritant chemicals."

The agency team ? comprising an epidemiologist, a pharmacologist/toxicologist and laboratory specialists ? will assist the Angolan Government to investigate the outbreaks and suggest measures for preventing further occurrences.

"This is complex work and WHO is consulting with experts and specialized institutions from other countries to explore ideas on appropriate lines of investigation," the statement noted.