In a statement issued by the Ministry of Health on Saturday, the two-day exercise started on Saturday in 15 districts in northern Uganda.

The districts include Adjumani, Apac, Arua, Gulu, Kitugum, Kotido, Katakwi, Masindi, Moyo, Moroto, Lira, Nakapiripirit, Nebbi, Yumbe and Pader.

According to the Ministry of Health, the 15 districts were selected because of their close proximity to Sudan after confirmed reports of a wild poliovirus outbreak in southern Sudan last year.

The program manager of the United Nations Expanded Program on Immunization, Dr. Isha Makumbi said that the exercise is intended to eliminate polio out of Uganda, by preventing all the dangers that would have come from Sudan.

Apart from polio vaccination, the children will be immunized against tetanus, measles, dewormed and also given vitamin A tablets.

This is the third round of Sub-National Immunization Days ( SNIDS) carried out in these districts.

The last campaign in the 15 districts was carried out in February and the Ministry of Health registered 93 percent coverage. According to the ministry statement about the immunization day, the SNIDS do not replace the routine national immunization days. The SNIDS are aimed at the strengthening of children's immunity.

Uganda has not had any polio case since 1997. However, Makumbi noted that the country can not be certified polio free since some countries in Africa still have cases of polio.

Poliomyelitis, to give it its full name, is a highly infectious viral disease that was once prevalent in Europe and the Americas but has been wiped out in much of the world, except in a dozen countries.

Polio spreads from the intestines and attacks the brain and spinal cord, causing paralysis, muscle wastage and even death.