Concern over polio outbreak

Eighteen cases of the polio virus have been confirmed in Yemen, marking the first known outbreak of the disease in six years. The cases were reported after the completion of a national polio immunisation campaign conducted in April. The campaign had been considered only a precautionary measure when it was originally announced following the resurgence of the disease in neighbouring countries. Yemen has been rated a polio-free country by the World Health Organization (WHO) since surveillance first began in 1996. The cases were reported in five governorates across the country, with the first four cited in Hodeidah on the western coast of Yemen, approximately 150 km from the capital, Sana. "Our results are normally sent to laboratories in Oman and Cairo. When we send the samples, we usually wait for at least 14 to 18 days to get the results," WHO country representative Dr Hashim al-Zain told IRIN from Hodeidah, where he was working on the response campaign. Polio can infect hundreds of people without displaying immediate symptoms and as a result the disease spreads quickly. The WHO considers a single confirmed case of polio paralysis to be evidence of an epidemic, particularly in countries where very few cases are found. "We are very serious about this, because any single case of polio is considered serious by the Ministry of Health [MoH]. Many officials are in Hodeidah, including the health minister and we are taking this very seriously,” Abdulhakim al-Kohlani, Yemen's General Director of Disease Control and Surveillance, told IRIN. “We are conducting a house-to-house immunisation campaign," he added. The investigation of current cases and intensive immunisation is being conducted jointly by the MoH and the WHO. "We are doing this campaign to ensure that we cover all areas by vaccination," al-Zain said. "What worried us is that cases from Hodeidah may go to other governorates in the country. We are going to identify the pockets of low coverage and have alerted all the governorate directors do to as much as possible to boost immunisation of children," he added. There has been speculation that the virus was introduced from Saudi Arabia or from Sudan but so far the source has not been positively identified. "There were reports of polio from Nigeria, which has spread to 12 countries in Africa, including Sudan. From there, a case from Sudan was imported to Saudi Arabia. I think this virus was definitely brought to Yemen, because we had no problem [with polio] for the last six years. If the virus was indigenous we would have seen it within the last six years," the Yemeni health official explained. The virus is also being analysed at the US Centers for Disease Control and Prevention (CDCP) in Atlanta, Georgia, in order to determine its exact sequence and to verify its origin. Polio is detected using a system called Acute Flaccid Paralysis (AFP) surveillance. In Yemen, doctors throughout the country have been instructed to undertake AFP surveillance. At least 90 percent of children under the age of five displaying AFP symptoms are reported and give stool samples, one immediately and a second within a period of 24-48 hours. The threat of the crippling disease spreading to neighbouring countries is of concern to health experts. "We are worried not solely about the situation in Yemen but from here polio can be transmitted to other polio-free countries: we share a border with Saudi Arabia and a border with Oman," he added. Polio most commonly afflicts children under five. Only one in 200 infected persons will display symptoms, which lead to irreversible paralysis within a few days. There are only six countries in the world which are considered polio-endemic: Nigeria, India, Pakistan, Niger, Afghanistan and Egypt. A total of 1,266 cases of polio were reported world-wide in the year 2004, according to the WHO.