30 research outputs found
Pulmonary Tuberculosis and Mycobacterium bovis, Uganda
Dat het vaststellen van het strafrechtelijk relevante causale verband geen gemakkelijke opgave is, bleek maar weer eens uit de Groningse HIV-zaak. Daarin was de vraag aan de orde of de verdachten die hun slachtoffers op een seksfeest hadden geïnjecteerd met besmet bloed, konden worden veroordeeld voor opzettelijke zware mishandeling, de later gebleken HIV-besmetting. De vraag is of de problemen met de strafrechtelijk relevante causaliteit niet voor een belangrijk deel kunnen worden opgelost door middel van materieelrechtelijke voorzieningen.
Transmission of foot and mouth disease at the wildlife/livestock interface of the Kruger National Park, South Africa : can the risk be mitigated?
In Southern Africa, the African buffalo (Syncerus caffer) is the natural reservoir of foot and mouth disease(FMD). Contacts between this species and cattle are responsible for most of the FMD outbreaks in cattleat the edge of protected areas, which generate huge economic losses. During the late 1980’s and 90’s, theerection of veterinary cordon fences and the regular vaccination of cattle exposed to buffalo contact at theinterface of the Kruger National Park (KNP), proved to be efficient to control and prevent FMD outbreaksin South Africa. However, since 2000, the efficiency of those measures has deteriorated, resulting in anincreased rate of FMD outbreaks in cattle outside KNP, currently occurring more than once a year.Based on retrospective ecological and epidemiological data, we developed a stochastic quantitativemodel to assess the annual risk of FMD virus (FMDV) transmission from buffalo to cattle herds present atthe KNP interface. The model suggests that good immunization of approximately 75% of the cattle pop-ulation combined with a reduction of buffalo/cattle contacts is an efficient combination to reduce FMDVtransmission to one infective event every 5.5 years, emulating the epidemiological situation observed atthe end of the 20th century, before current failure of control measures. The model also indicates that anincreasing number of buffalo present in the KNP and crossing its boundaries, combined with a reductionin the vaccination coverage of cattle herds at the interface, increases 3-fold the risk of transmission (oneinfective event per year).The model proposed makes biological sense and provides a good representationof current knowledge of FMD ecology and epidemiology in Southern Africa which can be used to discusswith stakeholders on different management options to control FMD at the wildlife livestock interface andupdated if new information becomes available. It also suggests that the control of FMD at the KNP inter-face is becoming increasingly challenging and will probably require alternative approaches to controlthis disease and its economic impact.University of Pretoria, South Africa. The project “Development of an epidemiological network to monitor the dynamics Foot and Mouth Disease at the GLTFCA” funded by the French Ministry of Foreign Affairs through the CORUS (Cooperation for Scientific and Academic Research).http://www.elsevier.com/locate/prevetmed2017-04-30hb2016Production Animal StudiesZoology and Entomolog
Method to assess farm-level vaccine and antibiotic usage utilizing financial documentation : a pilot study in a commercial pig farm in South Africa from 2016 to 2018
The purpose of the study was to develop a blueprint using financial documentation to
describe and quantify vaccine and antibiotic usage (ABU). This method was piloted
in a commercial pig farm in South Africa, with the ultimate hope to serve as a tool
in a future species-specific vaccine and ABU surveillance system. Data collection
was based on templates from the European Surveillance of Veterinary Antimicrobial
Consumption (ESVAC) network and the World Organisation for Animal Health (WOAH).
Invoices from 2016 to 2018 were used as the main data source. In addition, monthly
statement of accounts were used to check for missing invoices. An inventory check
was done to ensure that the correct antibiotic concentrations were used in subsequent
calculations. Livestock counts and slaughter statistics were also collected to be used
as denominator data. Cost calculations for the procurement of antibiotics and vaccines
were also done. The study showed that veterinary medicinal products were purchased
only from a single veterinary practice. A total of 291 invoices were issued over 3 years,
of which 2.75% (8/291) were missing and could therefore not be used in quantification.
Tetracyclines (453.65 ± 25.49 kg and 135.16 ± 3.31 mg/kg), followed by quinoxalines
(258.33 ± 8.04 kg and 77.07 ± 3.93 mg/kg) were used in the highest amounts, both
in terms of weight (kg) and adjusted for animal biomass (mg/kg). Vaccines used on
the farm targeted seven different diseases, namely enzootic pneumonia, erysipelas,
ileitis, infectious infertility, leptospirosis, neonatal pig diarrhea and porcine circovirus
disease. An average of 103 546 vaccine dosages was purchased for ZAR1 302,727 ( 69,561) per year. The study showed that invoices and monthly
statement of accounts, in combination with an inventory check and on-farm production
statistics, are useful data sources to quantify vaccine and ABU in the absence
of veterinary prescriptions. In addition, vaccinating pigs were more expensive than
administering antibiotics.The South African Medical Research Council (SAMRC) as a subgrant received from the Bill and Melinda Gates Foundation; a Fogarty International Center Global Infectious Disease research training grant, National Institutes of Health, to the University of Pittsburgh and the National Institute for Communicable Diseases.https://www.frontiersin.org/journals/veterinary-sciencedm2022Production Animal Studie
Progressive area elimination of bovine brucellosis, 2013-2018, in Gauteng Province, South Africa : evaluation using laboratory test reports
Bovine brucellosis is a zoonotic disease of global public health and economic importance.
South Africa has had a national bovine brucellosis eradication scheme since 1979; however, no
published report on elimination progress from any province exists. We analysed laboratory test
results of all cattle herds participating in the Gauteng Provincial Veterinary Services’ eradication
scheme between 2013 and 2018. Herd reactor status and within-herd seroprevalence, modelled using
mixed-effects logistic and negative binomial regression models, respectively, showed no significant
change over the period. However, provincial State Vet Areas, Randfontein (OR = 1.6; 95% CI: 1.2–2.1;
p < 0.001) and Germiston (OR = 1.9; 95% CI: 1.5–2.5, p = 0.008) had higher odds of reactor herds
than the Pretoria Area and within-herd prevalence count ratios for these areas were 1.5-fold greater
than the Pretoria State Vet Area (p < 0.001). Reactor herds were associated with increased herd size
(p < 0.001) and larger herd sizes were associated with lower within-herd prevalence (p < 0.001). Despite
no evidence of significant progress toward bovine brucellosis elimination in Gauteng province,
variability in bovine brucellosis prevalence between State Vet Areas exists. A public health and
farmer-supported strategy of ongoing district-based surveillance and cattle vaccination targeting
small- to medium-sized herds combined with compulsory test and slaughter of reactors in larger
herds is recommended for the province.The Gauteng Department of Agriculture and Rural Development and the APC was funded by the University of Pretoria.https://www.mdpi.com/journal/pathogensam2022Production Animal Studie
Do wild suids from Ndumo Game Reserve, South Africa, play a role in the maintenance and transmission of African swine fever to domestic pigs?
Warthogs (Phacochoerus africanus) and bushpigs (Potamochoerus larvatus) are considered as the wild reservoirs of ASF. They are both present in Ndumo Game Reserve (NGR), located in the Northern South African Province of KwaZulu on the border with Mozambique. In that area, the occurrence of tick-warthog sylvatic cycle of ASF has been suspected for years. To assess if wild suids represent a risk of ASF virus spillover to domestic pigs, wild suid abundance and incursions outside NGR boundaries were estimated using transect counts, fence patrols and camera traps. Also, the presence of Ornithodoros ticks was explored in 35 warthog burrows within NGR. In addition, blood samples were taken from 67 domestic pig farms located outside NGR to be tested for ASF antibodies. Information on interactions between domestic and wild suids and ASF occurrence was gathered using interviews with pig farmers (n = 254) in the study area. In conclusion, the bushpigs and warthog's population estimates in NGR are 5 and 3–5 individuals/km2, respectively. Both species move out of the reserve regularly (15.4 warthogs/day and 6.35 bushpigs/day), with movements significantly increasing in the dry season. Some farmers observed warthogs and bushpigs as far as 8 and 19 km from NGR, respectively, but no reports of direct wild-domestic suids interactions or ASF outbreaks. Also, no soft ticks were detected in all warthog burrows and all the pig blood samples were negative for ASF antibodies. The absence of ticks in warthog burrows, the absence of antibodies in pigs sampled, the absence of reported outbreaks, and no familiarity with ASF in the study area, suggest that a sylvatic cycle of ASF is, at present, unlikely in NGR. This conclusion must be confirmed by a larger survey of warthog burrows and monitoring potential antibodies in warthogs from NGR.American Society for Mammalogists;
National Research Foundation; Association
for African Universities; Belgian Technical
Cooperation.http://wileyonlinelibrary.com/journal/tbedhj2022Geography, Geoinformatics and MeteorologyMammal Research InstituteProduction Animal StudiesZoology and Entomolog
Living at the edge of an interface area in Zimbabwe : cattle owners, commodity chain and health workers’ awareness, perceptions and practices on zoonoses
BACKGROUND : In the great Limpopo transfrontier conservation area (GLTFCA), there is an increased interface
between wildlife and domestic animals, because rural households move their cattle into the game park in search
of grazing and watering resources. This creates opportunities for inter-species transmission of infectious diseases,
including zoonoses like brucellosis and tuberculosis, which may also pose a health risk to the local rural
communities. This study investigated the awareness, perceptions and practices on zoonoses amongst rural cattle
owners, commodity chain- and health-workers in three different localities around Gonarezhou National Park (GNP),
Zimbabwe, where the interface between wild and domestic animals varies.
METHODS : A cross-sectional study was conducted in Malipati, Chikombedzi and Chiredzi that are considered to be
high-, medium- and low-domestic animal-wildlife interface areas, respectively. Data was collected from cattle
owners, commodity chain and health-workers using a semi-structured questionnaire. To determine the public
health risk of food-borne zoonoses, their practices with regard to meat and milk consumptions, and measures they
take to prevent exposure to infections were assessed. Data were analyzed using descriptive statistics and principal
component analysis.
RESULTS : Most respondents (52.8 %, 102/193) were cattle owners, followed by health (30.1 %, 58/193) and lastly
commodity chain workers (17.1 %, 33/193). Overall 67.4 % (130/193) of the respondents were aware of zoonoses
with respective 48, 81.8, and 93.1 % of cattle owners, commodity chain, and health workers, being aware.
Significantly more cattle owners (P < 0.05) from medium and low interface areas were aware of zoonoses compared
to those from high interface areas. All categories of respondents cited anthrax (69.2 %), rabies (57.7 %), tuberculosis
(41.5 %) and brucellosis (23.9 %) as important zoonoses. About half (46.1 %; 89/193) of the respondents perceive
wildlife as important reservoirs of zoonoses. High proportions 98.4 % (190/193) and 96.4 % (186/193) of the
respondents indicated that they consume meat and milk, respectively. Access to game meat and milk from
informal markets was closely associated with consumption of raw meat and milk.
CONCLUSIONS : Fewer cattle owners from a high interface area of Malipati are aware of zoonoses compared to other areas due to combined effects of limited education and other factors disadvantaging these marginalised areas. This
may increase their risk of exposure to zoonoses, considering that consumption of raw meat and milk is common.
Thus, awareness campaigns may reduce the public health impact of zoonoses at the interface.This work was conducted within the framework of the Research Platform
“Production and Conservation in Partnership (RP-PCP).The French Ministry of Foreign Affairs, through the French
Embassy in Harare, Zimbabwe (RP-PCP grants) for which the principal
investigator (B.M. Gadaga) was a recipient.http://www.biomedcentral.com/bmcpublichealtham2016Production Animal Studie
Somatic cell count thresholds in composite and quarter milk samples as indicator of bovine intramammary infection status
The objective of the study was to establish an operational somatic cell count (SCC) threshold
to predict the presence of intramammary infection (IMI) in composite milk samples and
compare findings with those in quarter milk samples. South African dairy producers now
preferred composite milk samples for herd udder health analysis because of increasing cow
numbers, convenience of sampling and lower cost. A retrospective study was conducted on
345 461 composite and 89 638 quarter milk samples from South African herds. Variance
estimates for the proportion of quarter samples testing positive were adjusted to account
for the lack of their independence within individual cows. The IMI at SCC thresholds of
150 000 cells/mL and 200 000 cells/mL differed only by 3.26% in composite milk samples.
Youden’s index indicated the optimum SCC thresholds for composite and quarter milk
samples as 150 000 cells/mL and 200 000 cells/mL, respectively. At 150 000 cells/mL, sensitivity
(95% confidence intervals [CI]) in composite milk samples was 65.3% (64.0%, 66.6%) and
specificity was 66.8% (65.7%, 67.9%); and in quarter milk samples, sensitivity at 200 000 cells/
mL was 70.8% (69.5%, 72.0%) and specificity was 63.6% (62.4%, 64.8%). The likelihood of
infection for udders and quarters, respectively, was 1.034 and 1.327 at an SCC threshold of
150 000 cells/mL and 0.864 cells/mL and 1.177 cells/mL at 200 000 cells/mL. The area under
the curve of the receiver operating characteristics graph was 0.7084 and 0.7277 for composite
and quarter samples, respectively, indicating that the SCC test could be considered as a good
indicator of IMI in both sample types.http://www.ojvr.orgam2017Animal and Wildlife SciencesProduction Animal Studie
Validity of somatic cell count as indicator of pathogen-specific intramammary infections
The objective of this study was to determine whether somatic cell count (SCC) was an effective
test, with a sensitivity exceeding 85%, to determine species-specific bacterial infections.
In addition, the relation between the SCC and various udder pathogen groups was investigated.
SCC thresholds of greater than 200 000 cells/mL were used in quarter and greater than
150 000 cells/mL in composite milk samples. A retrospective study was conducted on a data
set for 89 635 quarter and 345 467 composite cow milk samples. Eleven SCC threshold values
were used to evaluate the diagnostic efficacy for the following bacteria: Gram-positive major
pathogens: Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalactiae and
Streptococcus uberis; Gram-negative major pathogens: Escherichia coli, Klebsiella pneumonia
and Serratia spp.; minor pathogens: coagulase-negative staphylococci, Micrococcus spp.,
Staphylococcus pseudintermedius, Streptococcus pyogenes, Enterococcus faecalis, Enterococcus canis,
Trueperella pyogenes and other Enterobacteriaceae. Sensitivity and specificity were calculated
taking the effect of clustering into account with quarter milk samples. Most samples yielding
major Gram-positive pathogens (88.9% in quarter and 79.9% in composite samples) and minor
pathogens (61.4% in quarter and 51.7% in composite samples) had SCC greater than
200 000 cells/mL. Sensitivity of the SCC test to detect major pathogens at an SCC threshold of
greater than 200 000 cells/mL in quarter samples and greater than 150 000 cells/mL in
composite milk samples was 88.2% and 84.2%, respectively, but specificity was low (57.7% and
52.8%, respectively).http://www.jsava.co.zaam2017Animal and Wildlife SciencesProduction Animal Studie
Knowledge of brucellosis, health-seeking behaviour, and risk factors for Brucella infection amongst workers on cattle farms in Gauteng, South Africa
Brucellosis in humans is under-detected and underreported in sub-Saharan Africa. Risk
factors associated with Brucella infection and health seeking behaviour in response to brucellosis-like
symptoms, amongst cattle farm workers and veterinary officials in South Africa, are unknown. Farm
workers and veterinary officials (N = 230) were screened for brucellosis using commercial Rose Bengal
Test (RBT®), IgM Enzyme-linked Immunoassay (ELISA)®, IgG ELISA® and the BrucellaCapt® test.
Knowledge of brucellosis and risk factors for exposure to Brucella were also investigated. Seroprevalence
varied according to test used: 10.1% (RBT®), 20.9% (IgG ELISA®) and 6.5% (BrucellaCapt®).
Only 22.2% (6/27) of veterinary officials opt to visit a clinic, doctor, or hospital in response to selfexperienced
brucellosis-like symptoms, compared to 74.9% (152/203) of farm workers (p < 0.001). Of
the BrucellaCapt® seropositive participants, 53% (7/15) did not visit a clinic in response to brucellosislike
symptoms. Weak evidence of an association between the handling of afterbirth or placenta
and infection of a short evolution (RBT®, IgM ELISA® and IgG ELISA® seropositive) was found
(OR = 8.9, 95% CI: 1.0–81.1, p = 0.052), and strong evidence of an association between this outcome
and the slaughter of cattle (OR = 5.3, 95% CI: 1.4–19.6, p = 0.013). There was strong evidence of a
positive association between inactive/resolved infection and veterinary officials vs. farm workers
exposed to seropositive herds (OR = 7.0, 95% CI: 2.4–20.2, p < 0.001), with a simultaneous negative
association with the handling of afterbirth or placenta (OR = 3.9, 95% CI: 1.3–11.3, p = 0.012). Findings
suggest a proportion of undetected clinical cases of brucellosis amongst workers on cattle farms
in Gauteng.Data Availability Statement: Data are available on request from the Gauteng Department of Agriculture and Rural Development.The University of Pretoria Animal and Zoonotic Diseases Institutional Research Theme (AZD IRT) and by the South African Health and Welfare Sector Education and Training Authority (HWSETA).https://www.mdpi.com/journal/pathogensam2022Centre for Veterinary Wildlife StudiesProduction Animal StudiesSchool of Health Systems and Public Health (SHSPH