Attachments
Description of the Event
Date when the trigger was met
08-09-2024
What happened, where and when?
Kenya is currently facing a public health challenge due to an outbreak of circulating vaccine-derived poliovirus type 2 (cVDPV2) with three (3) cases confirmed so far in Kenya in 2024. All are confirmed in a very volatile context with high risk of transmission and low vaccination coverage.
On 8th September 2024 out of the 60 samples, two were confirmed positive. KRCS received information from the Turkana County health department of two new polio cases in the refugee camp located in Turkana West sub-county. MOH has declared SAI -dates in response to the case in Kalobeyei camp. Round 1 planned: 02/10/2024– 06/10/2024 and KRCS will play its leading role on the social mobilization.
This case is in addition to a previous one reported in the same camp, following a positive sample on 15 July 2024. On 12 June 2024, a stool sample was collected from a 14-month-old male child residing in Turkana West, originally from Torit district in South Sudan, during KRCS routine surveillance in the refugee camp where KRCS provides health services. The stool sample underwent culture and sensitivity testing, although there was a significant delay in processing and receiving the results. On 15 July 2024, the sample tested positive for a circulating vaccine-derived poliovirus strain. Contact tracing was conducted, focusing on the child’s immediate contacts. The child was staying at the reception center and is believed to be part of a family that fled due to conflicts that erupted in late June between Ethiopian and South Sudanese communities, resulting in displacement and entry into Kenya.
Given the low vaccination coverage, border transmission risks, and localized factors, the circulation of a vaccine-derived virus presents a significant emergency.
Scope and Scale
On 31 May 2024, Uganda confirmed a case of circulating vaccine-derived poliovirus type 2 (cVDPV2) from an environmental sample collected at a surveillance site in Doko, Mbale City. Genetic sequencing revealed that this isolate was linked to a cVDPV2 strain previously detected in Garissa County, Kenya, which had been imported from Somalia. In late June 2024, intertribal conflicts between the Anyuak community of Ethiopia and the Nuer community of South Sudan erupted in the Kalobeyei refugee settlement, leading to fatalities and widespread displacement. Many fled back to their home countries, while others relocated to Nairobi for safety.
By 15 July 2024, when results from the first samples were received, the suspected first cVDPV2 case could not be traced, as the child was still at the reception center in Turkana West, Takuma County. It was suspected that these families were among those fleeing the June conflicts from areas experiencing ongoing outbreaks of vaccine-derived poliovirus. This posed significant challenges for contact tracing, particularly in such a volatile context, necessitating a thorough triangulation of areas with potential contacts along common displacement routes.
On 18 July 2024, a case of cVDPV2 was confirmed in a child at the Kakuma refugee camp in Turkana West Sub-County, Turkana County. The sample, collected on 12 June 2024, revealed the virus had 70 nucleotide differences from Sabin 2. Genetic sequencing showed all four isolates were linked to the cVDPV2 circulating in Banadir, Somalia. Additionally, on 8 September 2024, out of 60 samples collected, two more were confirmed positive. KRCS received notification from the Turkana County Health Department of two new polio cases in the refugee camp in Turkana West Sub-County, bringing the total number of confirmed cases to three.
The displacement and ongoing volatile situation in the refugee camps, as well as at border locations between Somalia and neighboring countries, poses a significant risk for further transmission. This underscores the need for enhanced contact tracing, particularly along common displacement routes and within camps. WHO assessed the overall national risk to be high due to overcrowded living conditions in the refugee camps, high malnutrition rates, poor water and sanitation facilities, and frequent population movements with Somalia.
Over the past 12 months, Kenya has conducted rapid campaigns, vaccinating millions of children using the oral polio vaccine. In response to the new cases, the Ministry of Health, with technical guidance from the Polio-Global Eradication Initiative and WHO, has planned a Supplementary Immunization Activity (SIA) rollout for the next month. Round 1 of the SIA is scheduled for 2 to 6 October 2024.
Nine counties have been prioritized for the SIA due to their links to cases in the camp, environmental factors, transport corridors, and low immunization coverage. This DREF operation aims to support the SIA in five high-risk counties—Busia, Bungoma, West Pokot, Trans Nzoia, and Turkana—targeting children under 10 years old. These counties were selected because they border Turkana, where the vaccine-derived poliovirus case was reported, and are located along the Western refugee transport corridor, bordering Uganda, which increases the transmission risk. Low vaccine coverage in these areas and refugee camps has further raised the risk of polio transmission.