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Kinyatta N, Wachira D, Githae R, Lusweti J, Ingonga J, Ichugu C, Maina C, Haji R, Kimani F, Musili R, Muli J, Kamau L. Detection of Wuchereria bancrofti in human blood samples and mosquitoes in Matayos, Busia County-Kenya. Sci Rep 2023; 13:19420. [PMID: 37940673 PMCID: PMC10632445 DOI: 10.1038/s41598-023-46329-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 10/30/2023] [Indexed: 11/10/2023] Open
Abstract
Lymphatic filariasis is a mosquito borne disease which leads to abnormal painful enlarged body parts, severe disability and social stigma. We screened Wuchereria bancrofti in Matayos constituency in Busia County. Blood samples were collected from 23 villages selected purposively based on clinical case reports. Finger prick and/or venous blood sampling and mosquito collections was carried out. Antigenaemia and filarial DNA prevalence were determined. Infection rates on mosquito pools were estimated and SPSS version 26 was used for descriptive statistics analysis. A total of 262 participants were recruited, 73.3% (n = 192) of the participants had no symptoms, 14.1% (n = 5.3) had swollen legs, 5.3% (n = 14) had painful legs and 3.8% (n = 10) with scrotal swellings. Average antigenemia prevalence was 35.9% (n = 94) and DNA prevalence was at 8.0% (n = 21). A total of 1305 mosquitoes were collected and pooled into 2-20 mosquitoes of the same species and from the same village. Two pools out of 78 were positive for filarial DNA with a minimum infection rate of 0.15%. From this study, antigenaemia and infected mosquitoes are an indication of active transmission. The clinical signs are evidence that filarial infections have been in circulation for over 10 years. The global climate change phenomenon currently happening has been shown to adversely affect the transmission of vector borne diseases and is likely to increase lymphatic filariasis transmission in the area. This study therefore recommends further screening before Mass Drug Administration, morbidity management and enhanced mosquito control Programmes are recommended in the study area.
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Yuko E, Sang R, Owino EA, Ingonga J, Matoke-Muhia D, Hassaballa IB, Junglen S, Tchouassi DP. Sandfly Blood-Feeding Habits and Competence in Transmitting Ntepes Virus, a Recently Discovered Member of the Genus Phlebovirus. BIOMED RESEARCH INTERNATIONAL 2022; 2022:4231978. [PMID: 36312854 PMCID: PMC9613380 DOI: 10.1155/2022/4231978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 10/07/2022] [Indexed: 11/17/2022]
Abstract
Phleboviruses transmitted by sandflies are among emerging public health threats. A novel Phlebovirus named Ntepes virus (NTPV) was recently described and found to infect humans from a wide geographic area in Kenya. However, the entomologic risk factors of this virus such as the potential vectors and the transmission cycles remain poorly defined. This study assessed the ability of the colonized sandfly Phlebotomus duboscqi to transmit NTPV and determined the bloodmeal host sources of field-collected sandflies from the area where NTPV was found in Baringo County, Kenya. Five-day old laboratory-reared P. duboscqi were orally challenged with an infectious dose of NTPV (≈106.0 pfu/ml) and incubated for up to 15 days postinfection. Individual sandflies were dissected into abdomens, legs, and salivary glands and screened for the virus infection by cell culture. Of the 205 virus-exposed sandflies, 19.5% developed non-disseminated infections in the midgut, with no evidence of virus dissemination or transmission in legs and salivary glands, respectively. The midgut infection rates decreased with increasing extrinsic incubation period (Spearman's correlation, ρ = -0.71). Blood-fed specimens analyzed by polymerase chain reaction (PCR) and sequencing of a region of the mitochondrial 12S rRNA, revealed almost exclusive feeding on humans (98%) represented by the sandflies Sergentomyia schwetzi, S. clydei, S. antennata, S. squamipleuris, S. africana, and Phlebotomus martini. One specimen of S. clydei had fed on cattle (2%). These findings suggest P. duboscqi is an incompetent laboratory vector of NTPV. The high human-feeding rate by diverse sandfly species increases the likelihood of human exposure to pathogens associated with these sandflies. Assessment of the susceptibility of Sergentomyia species to NTPV is recommended given their high human-feeding tendency.
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Kimutai A, Ngeiywa M, Mulaa M, Njagi PGN, Ingonga J, Nyamwamu LB, Ombati C, Ngumbi P. Repellent effects of the essential oils of Cymbopogon citratus and Tagetes minuta on the sandfly, Phlebotomus duboscqi. BMC Res Notes 2017; 10:98. [PMID: 28202077 PMCID: PMC5312532 DOI: 10.1186/s13104-017-2396-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 01/18/2017] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND The sandfly, Phlebotomus duboscqi is a vector of zoonotic cutaneous leishmaniasis (ZCL) that is an important public health problem in Eastern Africa. Repellents have been used for protection of humans against vectors of ZCL and other vectors that transmit killer diseases including malaria, Rift Valley fever, dengue, and yellow fever. The repellent effects of different doses of the essential oils from the lemon grass, Cymbopogon citratus and Mexican marigold, Tagetes minuta were evaluated in a two-chamber bioassay against 3- to 7-day-old unfed females of P. duboscqi in the laboratory. The results were compared with those that were obtained when test animals were treated with an equivalent dose of diethyl-3-methylbenzamide, which is a repellent that is commonly used as a positive control. RESULTS Overall, percentage repellency increased with increasing doses of the essential oils while biting rates decreased with increasing concentrations of the oils. Further, the oil of C. citratus was more potent than that of T. minuta with regard to protection time and biting deterrence. The effective doses at 50% (ED50) and at 90% (ED90) for the oil of C. citratus, were 0.04 and 0.79 mg/ml, respectively. Those of the oil of T. minuta were 0.10 and 12.58 mg/ml. In addition, the percentage repellency of 1 mg/ml of the essential oils of C. citratus and T. minuta against sandflies was 100% and 88.89%, respectively. A lower dose of 0.5 mg/ml of the oils, elicited 89.13% repellency for C. citratus and 52.22% for T. minuta. CONCLUSION The laboratory tests showed that the essential oils of the two plants were highly repellent to adult sand flies, P. duboscqi. Thus, the two essential oils are candidate natural repellents that can be used against P. duboscqi due to their high efficacy at very low doses, hence, the envisaged safety in their use over chemical repellents. It remains to carry out clinical studies on human subjects with appropriate formulations of the oils prior to recommending their adoption for use against the sandflies.
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Jumba BN, Anjili CO, Makwali J, Ingonga J, Nyamao R, Marango S, Choge JK, Khayeka-Wandabwa C. Evaluation of leishmanicidal activity and cytotoxicity of Ricinus communis and Azadirachta indica extracts from western Kenya: in vitro and in vivo assays. BMC Res Notes 2015; 8:650. [PMID: 26541197 PMCID: PMC4635543 DOI: 10.1186/s13104-015-1605-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 10/19/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Despite advances to targeted leishmanicidal chemotherapy, defies around severe toxicity, recent emergence of resistant variants and absence of rational vaccine still persist. This necessitates search and/or progressive validation of accessible medicinal remedies including plant based. The study examined both in vivo and in vitro response of L. major infection to combined therapy of Ricinus communis and Azadirachta indica extracts in BALB/c mice as the mouse model. A comparative study design was applied. RESULTS BALB/c mice, treated with combination therapy resulted in significantly (p < 0.05) larger reduction of lesion than those treated with monotherapies. The spleno-somatic index was found to be significantly low with combination therapy than monotherapies. Antiparasitic effect of A. indica and R. communis on amastigote with a 50 % inhibitory concentration (IC50) was of 11.5 and 16.5 µg mL(-1) respectively while combination therapy gave 9.0 µg ml(-1) compared to the standard drugs, Pentostam and amphotericin B which had an IC50 of 6.5 and 4.5 µg ml(-1) respectively. Optimal efficacy of A. indica and R. communis was 72 and 59.5 % respectively, combination therapy gave 88 %, while Pentostam and amphotericin B had 98 and 92 % respectively against amastigotes. Against promastigotes A. indica and R. Communis gave an IC50 of 10.1, 25.5 µg mL(-1) respectively, while combination, 12.2 µg mL(-1) against 4.1 and 5.0 µg ml(-1) for Pentostam and amphotericin B respectively. The optimal efficacy of the compounds against promastigotes was 78.0, 61.5 and 91.2 % (A. indica, R. communis and A. indica + R. communis respectively) against 96.5 and 98 % for Pentostam and amphotericin B respectively. The concentrations at optimal efficacy were significantly different (p < 0.05) among the test compounds. An evaluation of the IC50 values of the combination therapies clearly reveals synergistic effects. CONCLUSION Combination therapy of A. indica and R. communis had best antileishmanial activity than the monotherapies. The active ingredients of both R. communis and A. indica need to be fractionated, and studied further for activity against Leishmania parasites.
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Laban LT, Anjili CO, Mutiso JM, Ingonga J, Kiige SG, Ngedzo MM, Gicheru MM. Experimental therapeutic studies of Solanum aculeastrum Dunal. on Leishmania major infection in BALB/c mice. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2015; 18:64-71. [PMID: 25810878 PMCID: PMC4366745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 04/24/2014] [Indexed: 10/26/2022]
Abstract
OBJECTIVES Solanum acueastrum Dunal. has been shown to have some chemotherapeutic value. Leaf and berry water and methanol compounds of S. acueastrum were evaluated for possible antileishmanial activity In vivo on BALB/c mice and in vitro against Leishmania major promastigotes, amastigotes and vero cells. MATERIALS AND METHODS Dry S. aculeastrum berry and leaf material were extracted in methanol and water. L. major parasites were exposed to different concentrations of S. aculeastrum fruit and leaf compounds and the IC50 on the promastigotes, percentage of infection rate of macrophages by amastigotes and the toxicological effect on vero cells were determined. BALB/c mice were infected subcutaneously with 1×10(6) promastigotes and kept for four weeks to allow for disease establishment. Infected mice were treated with fruit and leaf methanolic and water compounds, amphotericin B (AmB), and sterile phosphate buffered saline (PBS). RESULTS Fruit methanol compound was most effective in inhibiting the growth of promastigotes with IC5078.62 μg/ml. Fruit water compound showed the best activity in inhibiting infection of macrophages by amastigotes. Fruit methanol compound was more toxic at Ld50=8.06 mg/ml to vero cells than amphotericin B. Analysis of variance computation indicated statistically significant difference in lesion sizes between experimental and control mice groups (P=0.0001). Splenic impression smears ANOVA indicated a highly significant difference in parasitic numbers between the experimental and the control groups (P=0.0001). CONCLUSION The results demonstrate that compounds from S. aculeastrum have potential anti-leishmanial activities and the medicinal use of the plant poses considerable toxicity against dividing vero cells.
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Kiige SG, Mutiso JM, Laban LT, Khayeka-Wandabwa C, Anjili CO, Ingonga J, Gicheru MM. F₁ cross-breed between susceptible BALB/c and resistant Swiss mice infected with Leishmania major exhibit an intermediate phenotype for lesion sizes and type 1 cytokines but show low level of total IgG antibodies. Scand J Immunol 2014; 79:283-91. [PMID: 24498914 DOI: 10.1111/sji.12159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 01/24/2014] [Indexed: 12/01/2022]
Abstract
Our current understanding of the host immune response during leishmaniases largely derives from studies performed in mice due to the intrusive techniques required to study infected human patients. Swiss mice are highly resistant to Leishmania infections in concordance with observed response in humans, while BALB/c mice indicate a high-susceptibility phenotype. Developing a cross-breed between BALB/c and Swiss mice may have important consequences on disease development, immune responses and parasite killing, as yet, response of the cross-breed to Leishmania infection is superficial. The aim of the present study was to determine disease course and immune responses in F₁ cross-breed between BALB/c and Swiss albino mice infected with L. major. Three mice groups were infected intradermally with stationary-phase L. major parasites with parental strains (BALB/c and Swiss albino) as controls. Lesion development was monitored weekly for 8 weeks and monocyte chemotactic protein (MCP-1), macrophage inflammatory protein (MIP-1α), interferon-gamma (IFN-γ) and IgG antibody quantified by enzyme-linked immunosorbent assay. The data were analysed using one-way analysis of variance and Tukey-Kramer test. Results indicated F₁ mice having intermediate lesion sizes, type 1 cytokine levels and footpad parasite loads as compared to the parental strains. However, the F₁ mice had low levels of IgG antibodies and parasite burden in the spleen. (P < 0.05). This study concludes that the F₁ cross-breed between resistant and susceptible mice may be used as a requisite model to study the role of genetics in leishmaniases and perhaps other intracellular parasites.
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Khayeka-Wandabwa C, Kutima H, Nyambati VCS, Ingonga J, Oyoo-Okoth E, Karani L, Jumba B, Githuku K, Anjili CO. Combination therapy using Pentostam and Praziquantel improves lesion healing and parasite resolution in BALB/c mice co-infected with Leishmania major and Schistosoma mansoni. Parasit Vectors 2013; 6:244. [PMID: 23968249 PMCID: PMC3765423 DOI: 10.1186/1756-3305-6-244] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 08/20/2013] [Indexed: 01/09/2023] Open
Abstract
Background Most natural host populations are exposed to a diversity of parasite communities and co-infection of hosts by multiple parasites is commonplace across a diverse range of systems. Co-infection with Leishmania major and Schistosoma mansoni may have important consequences for disease development, severity and transmission dynamics. Pentavalent antimonials and Praziquantel (PZQ) have been relied upon as a first line of treatment for Leishmania and Schistosoma infections respectively. However, it is not clear how combined therapy with the standard drugs will affect the host and parasite burden in concomitance. The aim of the current study was to determine the efficacy of combined chemotherapy using Pentostam and PZQ in BALB/c mice co-infected with L. major and S. mansoni. Methods The study used BALB/c mice infected with L. major and S. mansoni. A 3 × 4 factorial design with three parasite infection groups (Lm, Sm, Lm + Sm designated as groups infected with L. major, S. mansoni and L. major + S. mansoni, respectively) and four treatment regimens [P, PZQ, P + PZQ and PBS designating Pentostam®(GlaxoSmithKline UK), Praziquantel (Biltricide®, Bayer Ag. Leverkusen, Germany), Pentostam + Praziquantel and Phosphate buffered saline] as factors was applied. In each treatment group, there were 10 mice. Lesion development was monitored for 10 weeks. The parasite load, body weight, weight of the spleen and liver were determined between week 8 and week 10. Results Chemotherapy using the first line of treatment for L. major and S. mansoni reduced the lesion size and parasite loads but did not affect the growth response, spleen and liver. In the co-infected BALB/c mice, the use of Pentostam or PZQ did not result in any appreciable disease management. However, treatment with P + PZQ resulted in significantly (p < 0.05) larger reduction of lesions, net increase in the body weight, no changes in the spleen and liver weight and reduced Leishman-Donovan Units (LDU) and worm counts than BALB/c mice treated with Pentostam or PZQ alone. Conclusions The present study demonstrated that the combined first line of treatment is a more effective strategy in managing co-infection of L. major and S. mansoni in BALB/c mice.
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Makwali JA, Wanjala FME, Kaburi JC, Ingonga J, Byrum WW, Anjili CO. Combination and monotherapy of Leishmania major infection in BALB/c mice using plant extracts and herbicides. J Vector Borne Dis 2012; 49:123-130. [PMID: 23135005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023] Open
Abstract
BACKGROUND & OBJECTIVES Leishmaniasis is a growing health problem in many parts of the world. Efforts to find new chemotherapeutics for leishmaniasis remain a priority. This study was carried out to determine the effect of combination and monotherapies using plant extracts and herbicides on Leishmania major infection in BALB/c mice. METHODS The herbicides and saponin extract were purchased from Sigma. Roots of Plumbago capensis were collected from Karura forest, Nairobi, Kenya. Plant extractions were done in KEMRI at Center for Traditional Medicines and Drugs Research. RESULTS Lesion sizes after infection of BALB/c mice were similar in all the experimental groups till the onset of therapeutic treatments (p >0.05). At 15 days post-treatment, significant differences (p < 0.05) were discerned in the lesion sizes of the BALB/c mice in all the mono- and combined-treated groups. However, the combined therapies caused total elimination of the parasites from the lesions and significantly reduced parasite burden in liver and spleen compared to the untreated controls at the end of the experiment. INTERPRETATION & CONCLUSION The results of this study demonstrate that combination therapy using alternative administration of saponin, acriflavine, trifluralin and plumbagin is effective in treating L. major infection in mice. In this regard, an investigation into the efficacy of these combined therapies against other Leishmania strains should be explored further. Furthermore, studies with these combination therapies should be done on non-human primates such as the vervet monkey (Cercopithecus aethiops).
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Wabwoba BW, Anjili CO, Ngeiywa MM, Ngure PK, Kigondu EM, Ingonga J, Makwali J. Experimental chemotherapy with Allium sativum (Liliaceae) methanolic extract in rodents infected with Leishmania major and Leishmania donovani. J Vector Borne Dis 2010; 47:160-167. [PMID: 20834086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023] Open
Abstract
BACKGROUND & OBJECTIVES Several plant products have been tested and found to possess antileishmanial activity. The present study was undertaken to establish whether methanolic extract of Allium sativum Linn has antileishmanial activity in comparison to standard drugs. METHODS Methanolic extract of A. sativum bulbs was screened for in vitro and in vivo antileishmanial activity against Leishmania major strain (NLB 145) and L. donovani strain (NLB 065). Pentostam and Amphotericin B were used as standard drugs. BALB/c mice and golden hamsters (Mesocricetus auratus) were used in in vivo studies on L. major and L. donovani respectively. RESULTS The extract exhibited very low cytotoxicity (IC50 >450 μg/ml) against Vero cells. The extract had significantly better (p <0.001) leishmanicidal activity against both species (IC50 34.22 μg/ml to L. major, 37.41 μg/ml to L. donovani) than Pentostam. However, the activity was significantly lower (p <0.001) than that of Amphotericin B against both the species. At a concentration of 250 μg/ml, the extract induced the production of 60 μM of nitric oxide, a ten-fold up-regulation in activated macrophages. The multiplication indices for L. major amastigotes treated in 100 μg/ml were significantly different (p <0.05). Treatment with the extract, daily for 28 days led to a significant reduction (p <0.05) in footpad swelling in BALB/c mice; similar activity noticed in the treatment with standard drugs. The Leishman-Donovan Units (LDU) for the extract treated animals were significantly higher (p <0.05) than those of standard drugs, but lower compared to the negative control. INTERPRETATION & CONCLUSION Since the mechanism of action for the methanolic extract is apparently immunomodulatory, garlic compounds could be purified and tried as complementary medicine in the management of leishmaniases.
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Ngure PK, Ng'ang'a Z, Ingonga J, Rukunga G, Tonui WK. In vivo efficacy of oral and intraperitoneal administration of extracts of Warburgia ugandensis (Canellaceae) in experimental treatment of Old World cutaneous leishmaniasis caused by Leishmania major. AFRICAN JOURNAL OF TRADITIONAL, COMPLEMENTARY, AND ALTERNATIVE MEDICINES 2009; 6:207-12. [PMID: 20209014 DOI: 10.4314/ajtcam.v6i2.57093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The antileishmanial activity of extracts of Warburgia ugandensis Spraque (Canellaceae), a known traditional therapy in Kenya was evaluated in vivo. Treatment of infected BALB/c mice with W. ugandensis extracts orally resulted in a reduction of the size of lesions compared to the untreated control. The lesion sizes differed significantly for the four extracts (p=0.039) compared to the untreated control. For mice treated by intraperitoneal injection, the lesion sizes increased initially for the hexane, dichloromethane and ethyl acetate extracts and healed by day 42. The lesion sizes for mice treated with methanol increased steadily from 2.47mm to 3.57mm. The parasitic burden was significantly higher (p<0.001) in mice treated with methanol extracts and PBS compared to those treated with hexane, dichloromethane and ethyl acetate. This study demonstrated the antileishmanial potential of extracts of W. ugandensis.
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