PREVALENCE OF BRUCELLOSIS IN LIVESTOCK AND INCIDENCES IN HUMANS IN EAST AFRICA

Brucellosis is an emerging zoonotic disease that poses a threat to both livestock and public health in east Africa. There are several reports of occurrence of the disease in livestock populations especially in Tanzania and Kenya, suggesting chances of increased spread to humans, and the disease being misdiagnosed for malaria. The objective of this study was to determine brucellosis prevalence in livestock and incidence in humans among pastoralists and agro-pastoralists communities in some areas of Kenya and Tanzania. A total of 2349 ruminants were screened using different serological techniques, in the selected areas. Serum samples from the Southern Highlands Zone (SHZ), Northern zone (NZ) and Eastern Zone (EZ) were screened using Rose Bengal Plate Test (RBPT) antigen, and later positive samples were confirmed using competitive enzyme linked immune-sorbent assay (c-ELISA). Results showed prevalence of 11.4% in the SHZ (n=799), 2.4% in the EZ (n=169) and 1% in the NZ (n= 408). Milk ring test was used to test milk samples from Migori, West Pokot and Mwingi, and the prevalences recorded in cattle were 17.9% (n=56) in 2012 and 11.7 (n=77) in 2014. Within the same period, West Pokot recorded prevalence of up to 21.9% (n=96) in cattle and 16.7% (n=6) in goats. Generally, Migori had lower prevalence in Kenya, but being the third lower in Tanzania and Kenya with the prevalence being 4.3% (n=70) in goats and 2.2% (n=45) in goats. Serum from cattle and goats were tested using compliment fixation test (CFT); showing 0.9% (n=212) prevalence in Migori. In West Pokot, the prevalence was 4.0% (n=101) in cattle, 20% (n=100) in goats and 13.8% (=29) in sheep; whereas in Mwingi prevalence was 4.75% (n=43) and 9.5% (n=21) in cattle and goats respectively. A total of 1,140 human cases were followed up in selected study areas where livestock samples were collected, and an overall incidence of 22.7% (n=1140) was confirmed. Selected areas in Tanzania had an incidence of 28.2% (n=578) and in Kenya 17.1% (n=562). Brucellosis is endemic in many areas of Tanzania and Kenya and pose a high risk to human health.La brucellose est une zoonose qui constitue une menace pour la sante animale et humaine dans l\u2018 Afrique de l\u2018Est. Il existe beaucoup de rapports signalant la pr\ue9sence de cette maladie dans les populations d\u2019animaux, specialement en \ue9levage dans la Tanzanie et au Kenya. Ces rapports font aussi \ue9tat de ce qu\u2019il y ait des chances de contamination humaine, et la maladie est en train d\u2019\ueatre mal diagnostiqu\ue9e parce qu\u2019elle est confondue au paludisme. L\u2019objectif de cette \ue9tude \ue9tait de d\ue9terminer la pr\ue9valence de brucellose en \ue9levage et son incidence dans les humains, dans les communaut\ue9s de pastoralistes et agro-pastoralistes en Tanzanie et au Kenya. Un ensemble de 1,702 ruminant ont \ue9t\ue9 d\ue9pist\ue9s dans les zones d\u2019\ue9tude en se servant de techniques s\ue9rologiques diff\ue9rentes. Des \ue9chantillons de s\ue9rum venant de la zone Sud (SHZ), de la zone Nord (NZ) et de la zone Est (EZ) ont \ue9t\ue9 analyses par des tests de d\ue9tection d\u2019antig\ue8ne au Rose Bengale sur plaque (RBPT), et plus tard, les \ue9chantillons positifs ont \ue9t\ue9 confirmes par des \ue9preuves immuno-enzymatiques (c-ELISA). Les resultats montrait une pr\ue9valence de 11,4% dans la SHZ (n=799)\ua0; 2\ua0,4% dans l\u2019EZ (n=169) et 1% dans la NZ (n= 408). Des \ue9preuves de l\u2019anneau sur le lait ont permis de tester les \ue9chantillons de lait de Migori, West Pokot et Mwingi, et de pr\ue9valence enregistr\ue9e chez le bovin \ue9taient de 17,9% (n=56) en 2012 et 11,7 (n=77) en 2014. Dans la m\ueame p\ue9riode, West Pokot a enregistr\ue9 un taux de pr\ue9valence de 21.9% (n=96) chez le bovin et 16,7% (n=6) chez les caprins. De fa\ue7on g\ue9n\ue9rale, Migori exhibait de faibles taux de pr\ue9valence au Kenya, mais s\u2019est classe troisi\ue8me faible taux en Tanzanie et au Kenya avec une pr\ue9valence de 4,3% (n=70) chez les caprins 2,2% (n=45) chez les caprins. Du s\ue9rum pr\ue9lev\ue9 chez les bovins et caprins ont \ue9t\ue9 testes gr\ue2ce au test de fixation de compl\ue9ments (CFT)\ua0; montrait 0.9% (n=212) de pr\ue9valence en Migori. A West Pokot, la pr\ue9valence \ue9tait de 4,0% (n=101) chez les bovins, 20% (n=100) chez les caprins et 13,8% (=29) chez les ovins; tandis qu\u2019en Mwingi la pr\ue9valence \ue9tait de 4,75% (n=43) et 9,5% (n=21) respectivement chez les bovins et caprins. Un ensemble de 1,140 cas humains ont \ue9t\ue9 suivis dans la zone d\u2019\ue9tude ou les animaux ont \ue9t\ue9 \ue9chantillonn\ue9s. Une incidence globale de 22,7% (n=1140) a \ue9t\ue9 confirm\ue9e. Les zones s\ue9lectionn\ue9es en Tanzanie avaient une incidence de 28,2% (n=578) et 17,1% (n=562) au Kenya. Cet \ue9tude a montr\ue9 que la brucellose continue d\u2019\ueatre end\ue9mique dans plusieurs zones de la Tanzanie et du Kenya, et ceci constitue un grand risqu\ue9 pour la sant\ue9 humaine

Bovine tuberculosis in east Africa

The zoonotic Mycobacterium bovis is a pathogen of significance in the dairy industry in many parts of the world. Although the pathogen primarily affects cattle, it has a wide host range including humans. A cross-sectional study was carried out in three agro-ecological zones of Tanzania, namely the southern highlands zone (SHZ), eastern zone (EZ) and northern zone (NZ), to examine the status of the disease in cattle, in order to inform control measures. A total of 391, 169 and 401 cattle were tested for bovine tuberculosis (bTB) in the SHZ, EZ and NZ respectively using the Single Intradermal Comparative Cervical Tuberculin Test (SICTT). Results showed that the prevalence of bTB was higher (P<0.05) in EZ 2.37% (n = 169) compared to SHZ 1.3% (n=391) and NZ, where no positive result was recorded (n = 401). Thirty three cattle from SHZ and seven from EZ showed inconclusive results. In Kenya, 625 cattle from four sites within agro-pastoral and pastoral production systems were tested. In one area of Mwingi County, eastern Kenya, all the 161 cattle tested negative; while in the other three sites of Migori, in Nyanza, West Pokot and Laikipia in the Rift Valley, prevalence of 4-6% was obtained with SICTT. Bovine TB occurs in the region and may pose a public health threat through occupational activities and/or consumption of animal products, especially since no obvious clinical signs were observed in positive animals. Policy issues on how to deal with positive cases, creation of awareness on this important zoonotic disease, and a simple test to quickly identify sick animals in the field require urgent attention.La bact\ue9rie zoonotique Mycobacterium bovis est un agent pathog\ue8ne d\u2019importance dans l\u2019industrie laiti\ue8re partout dans le monde entier. Bien que l\u2019agent pathog\ue8ne affecte essentiellement les bovins, il peut infecter une large range d\u2019h\uf4tes l\u2019homme y compris. Une \ue9tude transversale a \ue9t\ue9 r\ue9alis\ue9e dans trois zones agro-\ue9cologiques de la Tanzanie, notamment la zone Sud (SHZ), la zone Est (EZ) et la zone Nord (NZ), afin d\u2019examiner la pr\ue9valence de cette maladie chez les bovins, en vue de d\ue9finir des mesures pour son contr\uf4le. Au total, 391, 169 et 401 bovins ont \ue9t\ue9 testes pour la tuberculose bovine (bTB) respectivement dans le SHZ, EZ et NZ. Le test Intradermique Comparatif a la Tuberculine Cervicale (SICTT). Les r\ue9sultats ont montr\ue9 que la pr\ue9valence de bTB \ue9tait \ue9lev\ue9e (p<0.05) en EZ 2.37% (n = 169) comparativement \ue0 SHZ 1.3% (n=391) et NZ, ou aucun cas positif n\u2019a \ue9t\ue9 enregistre (n = 401). Trente-trois bovins de SHZ et 7 de EZ ont montre des r\ue9sultats non conclusifs. Au Kenya, 625 bovins provenant de quatre sites au sein des syst\ue8mes de production agro-pastorale et pastorale ont \ue9t\ue9 testes. Dans une zone de Mwingi a l\u2019Est du Kenya, tous les 161 bovins ont \ue9t\ue9 testes n\ue9gative; tandis que dans les trois autres sites de Migori, en Nyanza, West Pokot et Laikipia dans la vall\ue9e du Rift, la pr\ue9valence \ue9tait de 4-6% avec le test SICTT. La tuberculose bovine est pr\ue9sent\ue9 dans la r\ue9gion et peut engendrer des menaces de sante publique au travers des activit\ue9s d\u2019\ue9levage et la consommation de viandes infect\ue9es, surtout qu\u2019aucun signe Clinique \ue9vident n\u2019a \ue9t\ue9 observe chez les animaux d\ue9pist\ue9s positifs. Il est important et urgent de d\ue9finir des mesures de gestion des cas positifs, de sensibiliser les populations sur les risques probables et de rendre disponibles des kits de tests rapides permettant d\u2019identifier \ue0 temps les animaux atteints

Short Communicaton: The socio-economic impact of helminth infections and the level of adoption of strategic helminth control by small ruminant farmers in Kakamega district, western Kenya

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Genetic variation in resistance to repeated infections with Heligmosomoides polygyrus bakeri, in inbred mouse strains selected for the mouse genome project

Since the publication of the mouse genome, attention has focused on the strains that were selected for sequencing. In this paper we report the results of experiments that characterized the response to infection with the murine gastrointestinal nematode Heligmosomoides polygyrus of eight new strains (A/J, C57BL/6, C3H, DBA/2, BALB/c, NIH, SJL and 129/J), in addition to the well-characterized CBA (poor responder) and SWR (strong responder) as our controls. We employed the repeated infection protocol (consisting of 7 superimposed doses of 125L3 each administered at weekly intervals, faecal egg counts in weeks 2, 4 and 6 and assessment of worm burdens in week 6) that was used successfully to identify quantitative trait loci for genes involved in resistance to H. polygyrus SWR, SJL and NIH mice performed indistinguishably and are confirmed as strong responder strains to H. polygyrus CBA, C3H and A/J mice all tolerated heavy infections and are assessed as poor responders. In contrast, DBA/2, 129/J and BALB/c mice performed variably between experiments, some tolerating heavy worm burdens comparable to those in poor responders, and some showing evidence of resistance, although only in one experiment with female 129/J females and one with female BALB/c was the pattern and extent of worm loss much like that in SWR mice. Because the genetic relationships between six of the strains exploited in this study are now well-understood, our results should enable analysis through single nucleotide polymorphisms and thereby provide more insight into the role of the genes that control resistance to H. polygyrus

High resolution mapping of chromosomal regions controlling resistance to gastrointestinal nematode infections in an advanced intercross line of mice

Fine mapping of quantitative trait loci (QTL) associated with resistance to the gastrointestinal parasite Heligmosomoides polygyrus was achieved on F6/F7 offspring (1076 mice) from resistant (SWR) and susceptible (CBA) mouse strains by selective genotyping (top and bottom 20% selected on total worm count in week 6). Fecal egg counts were recorded at weeks 2, 4, and 6, and the average was also analyzed. Blood packed cell volume in weeks 3 and 6 and five immunological traits (mucosal mast cell protease 1, granuloma score, IgG1 against adult worm, IgG1, and IgE to L4 antigen) were also recorded. On Chromosome 1 single-trait analyses identified a QTL with effects on eight traits located at about 24 cM on the F2 mouse genome database (MGD) linkage map, with a 95% confidence interval (CI) of 20-32 cM established from a multitrait analysis. On Chromosome 17 a QTL with effects on nine traits was located at about 18 cM on the MGD map (CI 17.9-18.4 cM). Strong candidate genes for the QTL position on Chromosome 1 include genes known to be involved in regulating immune responses and on Chromosome 17 genes within the MHC, notably the Class II molecules and tumor necrosis factor

Quantitative trait loci for resistance to Heligmosomoides bakeri and associated immunological and pathological traits in mice: comparison of loci on chromosomes 5, 8 and 11 in F2 and F6/7 inter-cross lines of mice

D.M. Menge, S. Nagda, F.A. Iraqi, R.J.M. Mugambi & J.P. Gibson are ILRI authorsA comparison of F2 and F6/7 inter-cross lines of mice, derived from CBA and SWR parental strains, has provided strong evidence for several previously undetected quantitative trait loci (QTL) for resistance to Heligmosomoides bakeri. Five QTL affecting average faecal egg counts and/or worm burdens in week 6 were detected on mouse chromosomes 5 (Hbnr9 and Hbnr10), 8 (Hbnr11) and 11 (Hbnr13 and Hbnr14). Three QTL for faecal egg counts in weeks 4 and 6 were found on both chromosomes 5 (Hbnr9) and 11 (Hbnr13 and Hbnr14). Two QTL for the mucosal mast cell protease 1 (MCPT1) response were located on chromosomes 8 (Hbnr11) and 11 (Hbnr13), two for the IgG1 antibody response to adult worms on chromosomes 5 (Hbnr10) and 8 (Hbnr11), two for PCV in week 6 on chromosomes 5 (Hbnr9) and 11 (Hbnr13), and two for the granulomatous response on chromosome 8 (Hbnr12) and 11 (Hbnr15). Our data emphasize that the control of resistance to H. bakeri is multigenic, and regulated by genes within QTL regions that have a complex range of hierarchical relationships

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

Background: The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications. Methods: ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery. Results: The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784. Conclusions: This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance. © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.Medical Research Council of South Africa gran