Kenya: Three-Month Wild Polio Virus Outbreak Response Assessment, 18 to 26 August 2013



On 9 May 2013, the Somalia Ministry of Health reported the first confirmed case of type 1 wild poliovirus (WPV1) in a 32-month old girl from Mogadishu with onset of acute flaccid paralysis (AFP) on 18 April 2013. A week later, on 16 May 2013, Kenya confirmed a case of WPV1 in a 4-month old girl from the Dadaab refugee camp in North Eastern Province of Kenya with date of onset 30 April 2013. Three months following the detection of the outbreak in Somalia, on 14 August 2013 the Kenya Medical Research Institute (KEMRI) issued an advanced notification of a case of WPV1 from a child living in Ethiopia with date of onset 10 July 2013. As of 30 August 2013, Kenya has confirmed 13 cases of WPV-1 whereas Somalia has confirmed 152 cases of WPV1 cases in 33 districts. The latest date of onset for Kenya’s polio outbreak is 14 July 2013. The 13 confirmed cases in Kenya are from the Garissa County in North Eastern Region and all Kenya’s cases are concentrated within the axis of the Dadaab refugee camp with proximity to the border with Somalia. Of the 13 WPV1 cases, 7 (54%) cases are from the refugee camps whereas 6 (46%) are from the host community. In the refugee camp, 4 (57%) are from Hagadera, 2 (29%) from IFO1 and 1 (14%) from Kambios camps. Among those from the host community, 3 (23%) are from Damanjale, 1 (8%) each from Mathegesi and Hamay, and Hulugho areas. Regarding the age distribution, 10 (77%) out of the 13 cases are <5 years (range of 4-60 months), while 3 (23%) are adults, two aged 19 and one aged 23 years. Nine (69%) of the 13 cases are female. Only 4 (31%) out of the 13 cases had received at least 4-doses of OPV, 2 (16%) had received 1-dose of OPV each and 7 (54%) had never received oral polio vaccine (OPV) before. Six (46%) of the cases occurred during the month of May (1-18th), 2 (15%) in the month of June (3rd & 14th) and 5 (39%) in July (2nd-14th), 2013. Although 7 (54%) of the cases had no travel history, 6 (46%) were from nomadic families and only one case had a travel history to Somalia. Two cases were related and had family contact before the onset of paralysis. The population dynamics in this area are complex. Many are nomadic pastoralists who are always on the move between Kenya and Somalia for trade, grazing and meeting relatives. There are strong links to clans or tribes rather than nationality. The host communities and the refugee camps interact with each other freely, creating a favorable environment for disease transmission. Even though the Kenya-Somalia border is officially closed, there are multiple informal border crossing points. Since January 2013, Kenya has detected 373 AFP cases, giving an annualized national non-polio (NP-AFP) detection rate of 2.64/100,000 children aged <15 years. Of the 373 AFP cases, 66 (18%) cases are from North Eastern Province. Twenty percent (13) of the AFP cases in North Eastern were detected during the polio SIAs.

This report summarizes the findings from a 3-month outbreak assessment conducted by an inter-agency team of experts (see annex 1) between 18 and 26 August 2013