National Research Repository
The National Research Fund facilitates research for the advancement of Science, Technology and Innovation. One of our core functions is to compile and maintain a national database of research and innovation projects funded by the Fund and other agencies as per the STI Act of 2013.
Browse Collections
Select a community to browse its collections.
Registry of Repositories in Kenya (RoRiK)
NRF is developing a Registry of Research Repositories in Kenya (RoRiK) in an effort to promote access to research data in the country.
Recent Submissions
Resurgence of Visceral and Cutaneous Leishmaniasis in Kajiado County, Kenya: A Coordinated Response and Entomological Survey.
(The Lancet Global Health, 2025) Matoke-Muhia, Damaris and Owino, Barrack and Kiplagat, Stephen and Mwangi, Hannah N. and Ingonga, Johnstone M. and Njenga, Daniel and Septer, Benny and Kitondo, Mwatela and Mwiti, Daniel and Magiri, Charles and Nyakundi, Hellen and Onditi, Juliet Akoth and Weihl, Sarah and Wenger, Catherine and Wamai, Richard and Satoskar, Abhay R. and Villinger, Jandouwe and Kamhawi, Shaden and Ndungu, Joseph and Masiga, Daniel,
Background: Leishmaniasis is of major global health concern with global elimination targets
set for 2030. East Africa accounts for ~75% of global visceral leishmaniasis (VL) cases.
Hence, attention to endemic, recurrent or emerging foci is critical to meeting global elimination
targets. In 2021, Kajiado County, on the southern border of Kenya with Tanzania, emerged
with cases of local transmission that necessitated this investigation.
Methods: This was a mixed methods coordinated response. We conducted a training for
clinicians, sensitised communities, and set up medical camps in four villages. Here we
screened the community for VL and other common ailments and undertook an entomological
survey for sandfly vector species in the same villages. We screened 100 individuals (males:
56; females: 44) for leishmaniasis using the rK39 rapid antibody test and by microscopic
examination. Dry blood spots (DBS) were collected from suspected cases. The samples were
further analyzed using PCR targeting the internal transcribed spacer 1 (ITS1) region, followed
1
Preprint not peer reviewed
This preprint research paper has not been peer reviewed. Electronic copy available at: https://ssrn.com/abstract=5242611
by sequencing for Leishmania species identification. For entomological surveys, sandfly
sampling was done in the four villages where medical camps were implemented, and another
four adjacent villages using CDC miniature or Silverbullet 2.0 light traps. Sandflies were
identified morphologically using taxonomic keys and the speciation confirmed by PCR analysis
of the cytochrome c oxidase subunit 1 (Cox1) gene and sequencing. We characterized sandfly
blood feeding preference by PCR analysis of the vertebrate cytochrome-b (Cyt-b) gene,
followed by HRM analysis and sequencing.
Results: Ten people (10/100; 10%) tested positive for VL (eight below 15 years old - six
males and two females). Of the 22 suspected cases with lesions suspected of cutaneous
leishmaniasis (CL), eight were confirmed as being infected with Leishmania tropica. We
trapped 4,781 sandflies and identified 1,624 specimens, consisting of 422 males and 1202
females, to species. They represented four Phlebotomus spp. and eight Sergentomyia spp.
The Phlebotomus spp. included Ph. martini (8.4%; n = 136), Ph. saevus (2.2%; n = 35), Ph.
orientalis (1.2%; n = 19), and Ph. guggisbergi (0.1%; n = 1). Overall, Sergentomyia species
(62.7%, 1019 specimens) were abundant. Of the 450 sandflies examined for presence of
Leishmania parasites by PCR, we detected DNA of Leishmania donovani in Sergentomyia
clydei (n = 13), Sergentomyia adleri (n = 4), S. antennatus (n = 2), and Ph. saevus (n = 1),
while L. tropica DNA was detected in Ph. saevus (n = 1). Analysis of the blood meal sources
of the 68 engorged sand flies showed that most fed on humans followed by goats. We also
detected blood from donkeys, mongoose and rock hyraxes.
Conclusion: We confirmed L. donovani and L. tropica as the main Leishmania species
responsible for VL and CL, respectively, in Kajiado. The presence of the parasites in humans
and the high human blood indices in sandflies indicate active transmission and high vector
human contact in the area. The co-occurrence of VL and CL is unusual and complicates case
management as the two forms are managed differently, and raises the possibilities of genetic
recombination in Leishmania parasites. Since access to diagnostic and treatment facilities are
at the core of infectious diseases management, and elimination efforts, the establishment of
two treatment Centres in Kajiado, for the first time, constitutes an important step in enhancing
community access to treatment and stemming the spread of leishmaniasis in the region. This
study thus contributes to global and national VL elimination targets, and demonstrates the
value of coordinated outbreak preparedness.
Association of Phlebotomus guggisbergi with Leishmania major and Leishmania tropica in a complex transmission setting for cutaneous leishmaniasis in Gilgil, Nakuru county, Kenya
(PLOSNeglectedTropical Diseases, 2019-10-18) Barrack O.Owino Milkah Mwangi, DamarisMatoke-Muhia, Yasser Alraey, Jackline , Johnstone M.Ingonga Alvaro Acosta-Serrano, Philip M. Ngumbi , Daniel K. Masiga
Background
Phlebotomus (Larroussius) guggisbergi is among the confirmed vectors for cutaneous leish
maniasis (CL) transmission in Kenya. This scarring and stigmatizing form of leishmaniasis
accounts for over one million annual cases worldwide. Most recent CL epidemics in Kenya
have beenreported in Gilgil, Nakuru County, where the disease has become a public health
issue. However, little is known about the factors that drive its transmission. Here, we sought
to determine the occurrence, distribution and host blood feeding preference of the vectors,
andto identify Leishmania species and infection rates in sandflies using molecular tech
niques. This information could lead to a better understanding of the disease transmission
andimprovement of control strategies in the area.
Methodology/ Principal findings
Anentomological survey of sandflies using CDC light traps was conducted for one week per
month in April 2016, and in June and July 2017 from five villages of Gilgil, Nakuru county;
Jaica, Sogonoi, Utut, Gitare and Njeru. Sandflies were identified to species level using mor
phological keys and further verified by PCR analysis of cytochrome c oxidase subunit I
(COI) gene. Midguts of female sandflies found to harbour Leishmania were ruptured and the
isolated parasites cultured in Novy-MacNeal-Nicolle (NNN) media overlaid with Schneider’s
insect media to identify the species. Leishmania parasite screening and identification in 198
randomly selected Phlebotomus females and parasite cultures was done by PCR-RFLP
analysis of ITS1 gene, nested kDNA-PCR and real-time PCR-HRM followed by sequencing.
Bloodmeal source identification was done by real-time PCR-HRM of the vertebrate cyto
chrome-b gene. Atotal of 729 sandflies (males: n = 310; females: n = 419) were collected
from Utut (36.6%), Jaica (24.3%), Sogonoi (34.4%), Njeru (4.5%), and Gitare (0.1%). These
were found to consist of nine species: three Phlebotomus spp. and six Sergentomyia spp.
Ph. guggisbergi was the most abundant species (75.4%, n = 550) followed by Ph. saevus
sensu lato (11.3%, n = 82). Sandfly species distribution across the villages was found to be
significantly different (p<0.001) with Jaica recording the highest diversity. The overall Leish
mania infection rate in sandflies was estimated at 7.07% (14/198). Infection rates in Ph. gug
gisbergi and Ph. saevus s.l. were 9.09% (12/132) and 3.57% (2/56) respectively. L. tropica
wasfound tobethepredominant parasite in Gilgil with an overall infection rate of 6.91% (13/
188) in Ph. guggisbergi (n = 11) and Ph. saevus s.l. (n = 2) sandflies. However, PCR analy
sis also revealed L. major infection in one Ph. guggisbergi specimen. Bloodmeal analysis in
the 74 blood-fed sandflies disclosed a diverse range of vertebrate hosts in Ph. guggisbergi
bloodmeals, while Ph. saevus s.l. fed mainly on humans.
Conclusions/ Significance
Thehigh infection rates of L. tropica and abundance of Ph. guggisbergi in this study con
firms this sandfly as a vector of L. tropica in Kenya. Furthermore, isolation of live L. tropica
parasites from Ph. saevus s.l. suggest that there are at least three potential vectors of this
parasite species in Gilgil; Ph. guggisbergi, Ph. aculeatus and Ph. saevus s.l. Molecular iden
tification of L. major infections in Ph. guggisbergi suggested this sandfly species as a poten
tial permissive vector of L. major, which needs to be investigated further. Sandfly host
preference analysis revealed the possibility of zoonotic transmissions of L. tropica in Gilgil
since the main vector (Ph. guggisbergi) does not feed exclusively on humans but also other
vertebrate species. Further investigations are needed to determine the potential role of
these vertebrate species in L. tropica and L. major transmission in the area.
Molecular detection of Leishmania donovani, Leishmania major, and Trypanosoma species in Sergentomyia squamipleuris sand flies from a visceral leishmaniasis focus in Merti sub-County, eastern Kenya
(BMC Parasites & Vectors, 2021) Barrack O. Owino, Jackline Milkah Mwangi, Steve Kiplagat, Hannah Njiriku Mwangi, Johnstone M. Ingonga, Alphine Chebet, Philip M. Ngumbi, Jandouwe Villinger, Daniel K. Masiga and Damaris Matoke‑Muhia
Background: Visceral leishmaniasis (VL) and zoonotic cutaneous leishmaniasis (ZCL) are of public health concern
in Merti sub‑County, Kenya, but epidemiological data on transmission, vector abundance, distribution, and reservoir
hosts remain limited. To better understand the disease and inform control measures to reduce transmission, we inves
tigated the abundance and distribution of sand fly species responsible for Leishmania transmission in the sub‑County
and their blood‑meal hosts.
Methods: We conducted an entomological survey in five villages with reported cases of VL in Merti sub‑County,
Kenya, using CDC miniature light traps and castor oil sticky papers. Sand flies were dissected and identified to the
species level using standard taxonomic keys and PCR analysis of the cytochrome c oxidase subunit 1 (cox1) gene.
Leishmania parasites were detected and identified by PCR and sequencing of internal transcribed spacer 1 (ITS1)
genes. Blood‑meal sources of engorged females were identified by high‑resolution melting analysis of vertebrate
cytochrome b (cyt‑b) gene PCR products.
Results: We sampled 526 sand flies consisting of 8 species, Phlebotomus orientalis (1.52%; n = 8), and 7 Sergentomyia
spp. Sergentomyia squamipleuris was the most abundant sand fly species (78.71%; n = 414) followed by Sergentomyia
clydei (10.46%; n = 55). Leishmania major, Leishmania donovani, and Trypanosoma DNA were detected in S. squami
pleuris specimens. Humans were the main sources of sand fly blood meals. However, we also detected mixed blood
meals; one S. squamipleuris specimen had fed on both human and mouse (Mus musculus) blood, while two Ph. orien
talis specimens fed on human, hyrax (Procavia capensis), and mouse (Mus musculus) blood.
Conclusions: Our findings implicate the potential involvement of S. squamipleuris in the transmission of Leishma
nia and question the dogma that human leishmaniases in the Old World are exclusively transmitted by sand flies of the Phlebotomus genus. The presence of Trypanosoma spp. may indicate mechanical transmission, whose efficiency
should be investigated. Host preference analysis revealed the possibility of zoonotic transmission of leishmaniasis and
other pathogens in the sub‑County. Leishmania major and L. donovani are known to cause ZCL and VL, respectively.
However, the reservoir status of the parasites is not uniform. Further studies are needed to determine the reservoir
hosts of Leishmania spp. in the area.
Keywords: Leishmania, Leishmaniasis, Sand fly, Trypanosoma, Sergentomyia, Phlebotomus, Zoonotic cutaneous
leishmaniasis, Visceral leishmaniasis, Kenya
Strengthening primary care systems for prevention & control of cardiovascular diseases in Kenya: feasibility study of health kiosks in markets “HEKIMA Study”
(BMJ GROUP, 2024-09-30) Lydia Kaduka, Jaymima Mbuka, Joanna Olale, Joseph Mutai, Elia Christelle, Rodgers Ochieng, Boniface Oyugi, Chrispine Oduor, Majella O’Keeffe, Harriet Boulding, Jamie Murdoch, Divya Parmar, Gilbert Kokwaro, Elijah Ogola, Seeromanie Harding
Objectives The increasing burden of cardiovascular diseases (CVDs) in Kenya threatens its healthcare system. There is a need for innovative models that improve equitable access to CVD prevention services. Community markets are social establishments with untapped potential to promote public health. This is a multiphased feasibility study that explores the potential of Health Kiosks in Markets (HEKIMA) to improve access to CVD prevention services. In this formative phase, the aim was to assess the readiness of primary healthcare centres (HCs) and community markets to jointly deliver CVD prevention services.
Design Mixed methods using concept mapping and readiness surveys. Concept mapping with 35 stakeholders from different sectors (health and non-health) to identify feasible priorities for HEKIMA. The readiness questionnaire contained 193 items which were based on the guidance of the WHO Handbook for Monitoring the Building Blocks of Health Systems and adapted to suit the context of a single HC.
Setting Vihiga County is located in western Kenya and has a population of 590 013. A total of 18 HCs and 19 markets were assessed, with 10 HCs and 15 markets included in the evaluation.
Results 91 statements were generated from concept mapping and distilled into 8 clusters, namely equipment and supplies, access and referral, communication, manpower, networks and linkages, practice, service delivery and health promotion. Agreed actions for HEKIMA were provision of efficient quality services, health promotion and partnerships sensitive to the local context. HCs and markets had established governance systems and basic infrastructure. The majority of the HCs lacked essential CVD medications. No HC–market interface existed but there was willingness for a partnership.
Conclusion There was strong consensus that an HC–market interface via community health worker manned kiosks could have a positive impact on health systems, markets and CVD prevention in vulnerable communities. However, significant infrastructural, technical and resource gaps were observed that need to be addressed.
Bioprospecting for Phytochemical Repellents and bio-pesticides of the Jigger Flea Tunga penetrans from the Western Kenya Flora.
(WIPO International Publication, 2022-03-03) Maurice V. Omolo, Paul K. Tarus, Joseph Owino, Regina Bwire, Vitman M. Wafula, Judith V. Adhiambo, Regina J. Cheptum, Vincent C. Terer, Anderson Misati, James Nonoh, John Muoma, Dennis Ochieno and Consolata Ngala
Discloses a composition comprising for treating jigger infestation, comprising Nicotine and related compounds present in Nicotiana tobaccum as bio-pesticides and antitungiasis of the jigger flea, Tunga penetrans. A single application of 10% formulation of Nicotine, nornicotine, Anabasine, Anatabine, Continine and myosmine in the ratio of 85: 2: 4: 7: 1: 1 respectively in petroleum jelly base of 90% and lemon Eucalyptus oil of 1 g on a jigger (6) infested victim's feet (6) gives 100% pesticide activity within 5-7 days as demonstrated by recovered foot (2B) and jigger scars (8). The said bio-chemicals, alone or in combination with one another and/ or other natural or synthetic pesticides exhibit activity against the jigger flea among other blood feeding insect & arachnid pests of humans and animals. Also discloses a method of formulating the bio-pesticide composition consisting of Nicotine and other biomolecules extracts from Nicotiana tobaccum.
