28 research outputs found
Mouse cytokine profile skewed towards Th2 in pregnancy during infection with Brucella abortus S19 strain
The two classes of cytokines Th1 and Th2 determine the type of immune response elicited. The Th2 immune response is associated with successful pregnancy. Brucellosis is an intracellular bacterium that elicits the Th1 response and is known to cause spontaneous abortion in mammalian species. This study sought to determine if Brucella infection causes spontaneous abortion by causing the circulating cytokine profile be Th1 dominant during pregnancy. Forty-eight Swiss white mice were used in this murine model and the S19 strain of Brucella abortus was used in as the infective agent. Pregnant mice in the test group were injected intraperitoneally with 105-8 CFU of Brucella and cytokine profile evaluated over the three trimesters of pregnancy. Pregnant mice in the control group were left to go through normal pregnancy and their cytokine profile evaluated over the three trimesters of pregnancy. Cytokines in serum samples were analyzed by Cytometric Bead Array. The data was analyzed using the Paired T- test and
Utilization and Satisfaction with Community Health Worker Services amongst Caregivers of Children under Five in Mwea West, Kirinyaga County
CHWs provide a possible solution for delivery of promotive and preventive interventions which have the potential to improve child health
An assessment of priority setting process and its implication on availability of emergency obstetric care services in Malindi District, Kenya
Introduction: In spite of the critical role of Emergency Obstetric Care in treating complications arising from pregnancy and childbirth, very few facilities are equipped in Kenya to offer this service. In Malindi, availability of EmOC services does not meet the UN recommended levels of at least one comprehensive and four basic EmOC facilities per 500,000 populations. This study was conducted to assess priority setting process and its implication on availability, access and use of EmOC services at the district level. Methods: A qualitative study was conducted both at health facility and community levels. Triangulation of data sources and methods was employed, where document reviews, in-depth interviews and focus group discussions were conducted with health personnel, facility committee members, stakeholders who offer and/ or support maternal health services and programmes; and the community members as end users. Data was thematically analysed. Results: Limitations in the extent to which priorities in regard to maternal health services can be set at the district level were observed. The priority setting process was greatly restricted by guidelines and limited resources from the national level. Relevant stakeholders including community members are not involved in the priority setting process, thereby denying them the opportunity to contribute in the process. Conclusion: The findings illuminate that consideration of all local plans in national planning and budgeting as well as the involvement of all relevant stakeholders in the priority setting exercise is essential in order to achieve a consensus on the provision of emergency obstetric care services among other health service priorities. Key words: Priority setting, decision making, EmOC, stakeholders, accountabilit
Alterations on peripheral B cell subsets following an acute uncomplicated clinical malaria infection in children
<p>Abstract</p> <p>Background</p> <p>The effects of <it>Plasmodium falciparum </it>on B-cell homeostasis have not been well characterized. This study investigated whether an episode of acute malaria in young children results in changes in the peripheral B cell phenotype.</p> <p>Methods</p> <p>Using flow-cytofluorimetric analysis, the B cell phenotypes found in the peripheral blood of children aged 2–5 years were characterized during an episode of acute uncomplicated clinical malaria and four weeks post-recovery and in healthy age-matched controls.</p> <p>Results</p> <p>There was a significant decrease in CD19<sup>+ </sup>B lymphocytes during acute malaria. Characterization of the CD19<sup>+ </sup>B cell subsets in the peripheral blood based on expression of IgD and CD38 revealed a significant decrease in the numbers of naive 1 CD38<sup>-</sup>IgD<sup>+ </sup>B cells while there was an increase in CD38<sup>+</sup>IgD<sup>- </sup>memory 3 B cells during acute malaria. Further analysis of the peripheral B cell phenotype also identified an expansion of transitional CD10<sup>+</sup>CD19<sup>+ </sup>B cells in children following an episode of acute malaria with up to 25% of total CD19<sup>+ </sup>B cell pool residing in this subset.</p> <p>Conclusion</p> <p>Children experiencing an episode of acute uncomplicated clinical malaria experienced profound disturbances in B cell homeostasis.</p
Mutations in the “a” Determinant Region of Hepatitis B Virus Genotype A among Voluntary Kenyan Blood Donors
Background: Occurrence of mutations within the major antigenic alpha determinant region of hepatitis B surface antigen (HBsAg can alter HBV antigenicity resulting in  failures in diagnosis, vaccine and hepatitis B immunoglobulin therapy. Objective: This study aimed at detection of mutations in the “a” determinant region of HBV surface antigen among voluntary blood donors in Kenya. Design: A cross sectional study involving serology and molecular techniques Settings: This study involved analysis of samples from blood transfusion centers Subjects: A total of 301 blood samples from donor blood were collected for the study. Methods: Sero-status for HBsAg was determined using Enzyme-Linked Immunosorbent Assay (ELISA). A fragment of the S gene including the "a" determinant was amplified by PCR from the HBsAg positive samples and sequenced for mutation analysis. Mutations and phylogenetic analyses were performed using Mega 6 software, Bioedit software and GENETYX® software version 9.1.0. Results: Out of the 301 samples tested 69/301 (22.9%) were Polymerase Chain Reaction (PCR) positive including 2/69(2.9%) were sero-negative for HBsAg. All isolates were genotype A, sub-genotype A1. A total of 29 mutations were observed of which 37.9% were located within the “a” determinant. Mutations T143M and K122R were the most frequent in this study. Escape mutations associated with diagnostic failure, vaccine and immunoglobulin therapy escape were also identified. Conclusions: These findings are important for policies related to vaccine implementation and therapeutic and diagnostic guidelines. Keywords: Escape mutants, genotype, hepatitis B virus, antigenic determinant, surface antigen
Mutations in the “a” Determinant Region of Hepatitis B Virus Genotype A among Voluntary Kenyan Blood Donors
Occurrence of mutations within the major antigenic alpha determinant region of hepatitis B surface antigen (HBsAg can alter HBV antigenicity resulting in  failures in diagnosis, vaccine and hepatitis B immunoglobulin therapy. This study aimed at detection of mutations in the “a” determinant region of HBV surface antigen among voluntary blood donors in Kenya. This was a cross sectional study involving serology and molecular techniques. This study involved analysis of samples from blood transfusion centers. A total of 301 blood samples from donor blood were collected for the study. Sero-status for HBsAg was determined using Enzyme-Linked Immunosorbent Assay (ELISA). A fragment of the S gene including the "a" determinant was amplified by PCR from the HBsAg positive samples and sequenced for mutation analysis. Mutations and phylogenetic analyses were performed using Mega 6 software, Bioedit software and GENETYX® software version 9.1.0. Out of the 301 samples tested 69/301 (22.9%) were Polymerase Chain Reaction (PCR) positive including 2/69(2.9%) were sero-negative for HBsAg. All isolates were genotype A, sub-genotype A1. A total of 29 mutations were observed of which 37.9% were located within the “a” determinant. Mutations T143M and K122R were the most frequent in this study. Escape mutations associated with diagnostic failure, vaccine and immunoglobulin therapy escape were also identified. These findings are important for policies related to vaccine implementation and therapeutic and diagnostic guidelines. Keywords: Escape mutants, genotype, hepatitis B virus, antigenic determinant, surface antige
Concomitant infections of Plasmodium falciparum and Wuchereria bancrofti on the Kenyan coast
BACKGROUND: Anopheles gambiae s.l. and An. funestus are important vectors of malaria and bancroftian filariasis, which occur as co-endemic infections along the Kenyan Coast. However, little is known about the occurrence and prevalence of concomitant infections of the two diseases in mosquito and human populations in these areas. This study reports the prevalence of concomitant infections of Plasmodium falciparum and Wuchereria bancrofti in mosquito and human populations in Jilore and Shakahola villages in Malindi, Kenya. METHODS: Mosquitoes were sampled inside houses by pyrethrum spray sheet collection (PSC) while blood samples were collected by finger prick technique at the end of entomological survey. RESULTS: A total of 1,979 female Anopheles mosquitoes comprising of 1,919 Anopheles gambiae s.l and 60 An. funestus were collected. Concomitant infections of P. falciparum sporozoites and filarial worms occurred in 1.1% and 1.6% of An. gambiae s.l collected in Jilore and Shakahola villages respectively. Wuchereria-infected mosquitoes had higher sporozoite rates compared to non-infected mosquitoes, but multiple infections appeared to reduce mosquito survivorship making transmission of such infections rare. None of the persons examined in Shakahola (n = 107) had coinfections of the two parasites, whereas in Jilore (n = 94), out of the 4.3% of individuals harbouring both parasites, 1.2% had P. falciparum gametocytes and microfilariae and could potentially infect the mosquito with both parasites simultaneously. CONCLUSION: Concerted efforts should be made to integrate the control of malaria and bancroftian filariasis in areas where they co-exist
High prevalence of <i>Rickettsia africae</i> variants in <i>Amblyomma variegatum</i> ticks from domestic mammals in rural western Kenya: implications for human health
Tick-borne spotted fever group (SFG) rickettsioses are emerging human diseases caused by obligate intracellular Gram-negative bacteria of the genus Rickettsia. Despite being important causes of systemic febrile illnesses in travelers returning from sub-Saharan Africa, little is known about the reservoir hosts of these pathogens. We conducted surveys for rickettsiae in domestic animals and ticks in a rural setting in western Kenya. Of the 100 serum specimens tested from each species of domestic ruminant 43% of goats, 23% of sheep, and 1% of cattle had immunoglobulin G (IgG) antibodies to the SFG rickettsiae. None of these sera were positive for IgG against typhus group rickettsiae. We detected Rickettsia africae–genotype DNA in 92.6% of adult Amblyomma variegatum ticks collected from domestic ruminants, but found no evidence of the pathogen in blood specimens from cattle, goats, or sheep. Sequencing of a subset of 21 rickettsia-positive ticks revealed R. africae variants in 95.2% (20/21) of ticks tested. Our findings show a high prevalence of R. africae variants in A. variegatum ticks in western Kenya, which may represent a low disease risk for humans. This may provide a possible explanation for the lack of African tick-bite fever cases among febrile patients in Kenya
Knowledge and Adherence to the National Guidelines for Malaria Diagnosis in Pregnancy among Health-Care Providers and Drug-Outlet Dispensers in Rural Western Kenya
Prompt diagnosis and effective treatment of acute malaria in pregnancy (MiP) is important for the mother and fetus; data on health-care provider adherence to diagnostic guidelines in pregnancy are limited. From September to November 2013, a cross-sectional survey was conducted in 51 health facilities and 39 drug outlets in Western Kenya. Provider knowledge of national diagnostic guidelines for uncomplicated MiP were assessed using standardized questionnaires. The use of parasitologic testing was assessed in health facilities via exit interviews with febrile women of childbearing age and in drug outlets via simulated-client scenarios, posing as pregnant women or their spouses. Overall, 93% of providers tested for malaria or accurately described signs and symptoms consistent with clinical malaria. Malaria was parasitologically confirmed in 77% of all patients presenting with febrile illness at health facilities and 5% of simulated clients at drug outlets. Parasitological testing was available in 80% of health facilities; 92% of patients evaluated at these facilities were tested. Only 23% of drug outlets had malaria rapid diagnostic tests (RDTs); at these outlets, RDTs were offered in 17% of client simulations. No differences were observed in testing rates by pregnancy trimester. The study highlights gaps among health providers in diagnostic knowledge and practice related to MiP, and the lack of malaria diagnostic capacity, particularly in drug outlets. The most important factor associated with malaria testing of pregnant women was the availability of diagnostics at the point of service. Interventions that increase the availability of malaria diagnostic services might improve malaria case management in pregnant women
High Prevalence of Rickettsia africae Variants in Amblyomma variegatum Ticks from Domestic Mammals in Rural Western Kenya: Implications for Human Health
Tick-borne spotted fever group (SFG) rickettsioses are emerging human diseases caused by obligate intracellular Gram-negative bacteria of the genus Rickettsia. Despite being important causes of systemic febrile illnesses in travelers returning from sub-Saharan Africa, little is known about the reservoir hosts of these pathogens. We conducted surveys for rickettsiae in domestic animals and ticks in a rural setting in western Kenya. Of the 100 serum specimens tested from each species of domestic ruminant 43% of goats, 23% of sheep, and 1% of cattle had immunoglobulin G (IgG) antibodies to the SFG rickettsiae. None of these sera were positive for IgG against typhus group rickettsiae. We detected Rickettsia africae–genotype DNA in 92.6% of adult Amblyomma variegatum ticks collected from domestic ruminants, but found no evidence of the pathogen in blood specimens from cattle, goats, or sheep. Sequencing of a subset of 21 rickettsia-positive ticks revealed R. africae variants in 95.2% (20/21) of ticks tested. Our findings show a high prevalence of R. africae variants in A. variegatum ticks in western Kenya, which may represent a low disease risk for humans. This may provide a possible explanation for the lack of African tick-bite fever cases among febrile patients in Kenya