Across Kenya and the wider region, monthly collections of wastewater and stool samples make their way to the Kenya Medical Research Institute (KEMRI), where laboratory analysis searches for early evidence of poliovirus. Early detection of poliovirus, a highly contagious disease that can cause permanent paralysis in children, enables Kenya and neighbouring countries to confirm cases quickly and launch targeted interventions before the virus spreads through vulnerable communities.
To strengthen the region's ability to detect poliovirus and other diseases, Kenya has upgraded KEMRI's laboratory to a new state-of-the-art building. Supported by WHO and the Gates Foundation under the Global Polio Eradication Initiative, the enhanced laboratory features advanced genomic sequencing technologies, virus isolation capabilities, molecular diagnostic platforms, and expanded storage facilities that will reduce diagnostic turnaround times for poliovirus and other infectious diseases across the region.
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Professor Peter Borus from WHO overlooks one of Kenya's 24 environmental sampling sites in Kibera, where wastewater is collected monthly and transported to KEMRI's laboratory for analysis.
"Environmental surveillance has played a very critical role as part of the Kenya’s polio surveillance strategy," explained Professor Peter Borus, "last year, we had a total of five confirmed variant poliovirus cases, and all of them were first detected through environmental sampling."
Since poliovirus spreads through faecal material, infected people shed the virus into sewage systems, making wastewater monitoring an effective way to detect the disease early.
"Environmental surveillance has played a very critical role as part of the Kenya’s polio surveillance strategy," explained Professor Peter Borus, "last year, we had a total of five confirmed variant poliovirus cases, and all of them were first detected through environmental sampling."
Since poliovirus spreads through faecal material, infected people shed the virus into sewage systems, making wastewater monitoring an effective way to detect the disease early.
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"Environmental sampling is essential because up to 90% of poliovirus infections cause no symptoms”, explained Charles Korir, Global Polio Eradication Initiative Coordinator for Kenya. “This means that infected people can unknowingly spread the virus through sewage without ever seeking medical care,” he added.
In Kibra Sub-County, where Samuel Muturi has collected samples for over 10 years, this surveillance is particularly vital. With over 300,000 residents and 80% living in informal settlements, "testing these water sources regularly helps us catch polio early before it spreads through such densely populated areas," Samuel noted.
In Kibra Sub-County, where Samuel Muturi has collected samples for over 10 years, this surveillance is particularly vital. With over 300,000 residents and 80% living in informal settlements, "testing these water sources regularly helps us catch polio early before it spreads through such densely populated areas," Samuel noted.
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Kenya became the second African country after Nigeria to establish environmental surveillance for polio in 2013, starting with just two sampling sites that have since expanded to 24 locations nationwide.
"A few years ago, the Ministry of Health and WHO selected this spot as a collection site. We were involved in choosing the location and trained on safe sample collection," said Peter Adoyo, a community health promoter from Kibera who helps Samuel collect samples each month. "Now we collect samples in the first week of each month and send them to the labs for analysis.”
“It’s always encouraging to get the results back from the lab and see that the population that we serve are safe," said Peter Adoyo.
"A few years ago, the Ministry of Health and WHO selected this spot as a collection site. We were involved in choosing the location and trained on safe sample collection," said Peter Adoyo, a community health promoter from Kibera who helps Samuel collect samples each month. "Now we collect samples in the first week of each month and send them to the labs for analysis.”
“It’s always encouraging to get the results back from the lab and see that the population that we serve are safe," said Peter Adoyo.
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Evans Komen, a Senior Laboratory Technologist who has worked at KEMRI for over 10 years, helps investigate these samples each month.
"Once we receive the samples, they undergo thorough investigation," said Evans Komen. "Our results are then shared with the Ministry of Health and WHO to guide vaccination campaigns and initiate a rapid response."
In the past 10 years, Kenya with support from WHO, has conducted over 8 targeted polio vaccination campaigns, administering over 60 million polio vaccine doses and reaching millions of children. Each campaign was initiated from positive poliovirus results which were investigated at KEMRI’s laboratory.
This response follows the detection of polioviruses, including five cases identified across two counties in 2024. No new cases have been reported in the past 15 months, thanks to targeted and effective interventions.
"Once we receive the samples, they undergo thorough investigation," said Evans Komen. "Our results are then shared with the Ministry of Health and WHO to guide vaccination campaigns and initiate a rapid response."
In the past 10 years, Kenya with support from WHO, has conducted over 8 targeted polio vaccination campaigns, administering over 60 million polio vaccine doses and reaching millions of children. Each campaign was initiated from positive poliovirus results which were investigated at KEMRI’s laboratory.
This response follows the detection of polioviruses, including five cases identified across two counties in 2024. No new cases have been reported in the past 15 months, thanks to targeted and effective interventions.
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The new WHO-accredited laboratory expansion establishes Kenya as a regional center of excellence, extending its impact beyond Kenya to serve multiple countries across WHO's African and Eastern Mediterranean regions.
"We are a unique laboratory as we serve as a regional diagnostic hub, processing samples from Kenya, Somalia, Ethiopia, Uganda, Djibouti, Eritrea, and Yemen," said Shadrack Barmasai, Research Scientist from KEMRI.
"We are a unique laboratory as we serve as a regional diagnostic hub, processing samples from Kenya, Somalia, Ethiopia, Uganda, Djibouti, Eritrea, and Yemen," said Shadrack Barmasai, Research Scientist from KEMRI.
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The new KEMRI facility is equipped with cutting-edge molecular diagnostic platforms, expanded sample storage capacity, and improved biosafety standards, ensuring timely, accurate results. In particular new genetic sequencing capacities is going to reduce turnaround time for sample testing significantly.
"Having worked here for 28 years, this upgrade will really change how we operate,” said Joanne Hassan, laboratory manager at KEMRI. “We used to send our results to Atlanta for final confirmation which can take anywhere between three and six weeks. With the new lab capacity in Kenya, we are going to get them in less than one week."
"Having worked here for 28 years, this upgrade will really change how we operate,” said Joanne Hassan, laboratory manager at KEMRI. “We used to send our results to Atlanta for final confirmation which can take anywhere between three and six weeks. With the new lab capacity in Kenya, we are going to get them in less than one week."
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"We can now tell the Ministry of Health the specific type of virus we're dealing with, which helps them plan the most effective response," added Collins Steriot, a research scientist at KEMRI's Polio Genomics Laboratory.
"With our enhanced capacity and reduced turnaround times, we can help Kenya and other countries in the region stop outbreaks before they spread to larger populations, rather than waiting weeks for results while the situation worsens."
"With our enhanced capacity and reduced turnaround times, we can help Kenya and other countries in the region stop outbreaks before they spread to larger populations, rather than waiting weeks for results while the situation worsens."
For Additional Information or to Request Interviews, Please contact:
Genna Print
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