Epidemiological investigation of Leptospira spp. in a dairy farming enterprise after the occurrence of three human leptospirosis cases

An epidemiological investigation was conducted in an unvaccinated dairy farming enterprise in which three workers on one of the milking herds (Herd 1) were diagnosed with leptospirosis due to serovars Hardjo (H) (n = 2) and Pomona (P) (n = 1) between January and March 2015. Blood and urine samples were collected from milking cows in Herd 1 (N = 230) and Herd 2 (N = 400), rising one‐ (R1, N = 125) and rising two‐year‐old (R2, N = 130) replacement heifers, and four pigs associated with Herd 1, in March 2015. Sera were tested using the MAT for serovars H, P, Copenhageni (C), Ballum (B) and Tarassovi (T), and urine samples were tested by qPCR. Seventy‐five per cent of 109 cows in Herd 1 and 36% of 121 in Herd 2 were seropositive (≥48), predominantly to H and P, and 23% of 74 cows in Herd 1 and 1% of 90 cows in Herd 2 were qPCR positive. Fifty‐five per cent of 42 R2 heifers were seropositive to T. No R1 and 17% of 42 R2 heifers were qPCR positive. Subsequently, all cattle were vaccinated for H and P, and Herds 1 and 2 were given amoxicillin. After the booster vaccination, 7% of 91 in Herd 1, 2% of 82 in Herd 2 and 11% of 38 R1 heifers (sampled as R2) were PCR positive. After the amoxicillin treatment, no cows in Herd 1 and 5% of 62 cows in Herd 2 were urine PCR positive. Calves and pigs were seropositive to H, P, C and B. Vaccination and antibiotic treatment appeared effective in reducing the risk of exposure of workers to vaccine serovars. However, evidence of non‐vaccine serovars indicated that workers likely remain at risk of exposure to Leptospira.     

Shedding and Seroprevalence of Pathogenic Leptospira spp. in Sheep and Cattle at a New Zealand Abattoir

A cross‐sectional study was carried out on sheep and cattle slaughtered at a New Zealand abattoir from September to November 2010 to investigate the supplier‐specific shedding rate, renal carriage rate and seroprevalence of leptospires. In the 2008/2009 season, this abattoir experienced three human leptospirosis cases from 20 staff, of which two were hospitalized. Urine, kidney and blood samples were collected from carcasses of 399 sheep (six suppliers, 17 slaughter lines) and 146 cattle (three suppliers, 22 slaughter lines). The urine and kidney samples were tested by quantitative real‐time PCR (qPCR), while serum samples (from coagulated blood samples) were tested by microscopic agglutination test (MAT). In total, 27% (73/274; 95% CI: 18–37) of urine samples tested positive by qPCR. Species‐specific shedding rates (prevalence of positive urine qPCR) were 31% (95% CI: 17–48) for sheep and 21% (95% CI: 14–30) for cattle. For 545 kidney samples tested, 145 were qPCR positive (27%; 95% CI: 17–39). The average prevalence of kidney qPCR positivity was 29% (95% CI: 17–45) for sheep and 21% (95% CI: 15–28) for cattle. Three hundred and thirty of 542 sampled sheep and cattle had antibodies against Leptospira borgpetersenii serovar Hardjobovis (Hardjobovis) and/or Leptospira interrogans serovar Pomona (Pomona), based on reciprocal MAT titre ≥1 : 48 (overall seroprevalence of 61%; 95% CI: 48–73). Seroprevalence was 57% (95% CI: 40–72) for sheep and 73% (95% CI: 59–83) for cattle. Among the seropositive animals, 41% (70/170; 95% CI: 30–54) were shedding (tested positive by urine qPCR) and 42% (137/330; 95% CI: 30–54) had renal carriage (tested positive by kidney qPCR). Some risk management options for abattoirs or farms to prevent human leptospirosis infections include vaccination of maintenance hosts, the use of personal protective equipment, and the application of urine qPCR to detect shedding status of stock as surveillance and as an alert.     

City sanitation and socioeconomics predict rat zoonotic infection across diverse neighbourhoods

Rat‐associated zoonoses transmitted through faeces or urine are of particular concern for public health because environmental exposure in homes and businesses may be frequent and undetected. To identify times and locations with greater public health risks from rats, we investigated whether rat characteristics, environmental features, socioeconomic factors, or season could predict rat infection risk across diverse urban neighbourhoods. In partnership with a pest management company, we sampled rats in 13 community areas along an income gradient in Chicago, a large city where concern about rats has increased in recent years. We collected kidneys for Leptospira spp. testing and colon contents for aerobic bacteria such as Salmonella spp. and Escherichia coli. Of 202 sampled rats, 5% carried Leptospira spp. and 22% carried E. coli. Rats were significantly more likely to carry Leptospira spp. on blocks with more standing water complaints in higher‐income neighbourhoods (OR = 6.74, 95% CI: 1.54–29.39). Rats were significantly more likely to carry E. coli on blocks with more food vendors (OR = 9.94, 2.27–43.50) particularly in low‐income neighbourhoods (OR = 0.26, 0.09–0.82) and in the spring (OR = 15.96, 2.90–88.62). We detected a high diversity of E. coli serovars but none contained major virulence factors. These associations between environmental features related to sanitation and infection risk in rats support transmission through water for Leptospira spp. and faecal–oral transmission for E. coli. We also found opposing relationships between zoonotic infection risk and income for these two pathogens. Thus, our results highlight the importance of sanitation for predicting zoonotic disease risks and including diverse urban areas in pathogen surveillance to mitigate public health risks from rats.     

Seroprevalence and Risk Factors for Leptospira Seropositivity in Beef Cattle,Sheep and Deer Farmers in New Zealand

Leptospirosis is a global zoonosis that in New Zealand affects primarily people occupationally exposed to livestock. The objective of this study was to estimate the seroprevalence of five Leptospira serovars in farmers working on cattle, sheep and deer farms that had the serological status of animals previously assessed and to identify risk factors for farmer seropositivity. A total of 178 farmers from 127 properties participated in the study. Blood samples were tested using the microscopic agglutination test (MAT) for the presence of antibodies to Leptospira. Samples with a MAT titre ≥48 were considered seropositive. Using Bayesian statistical analysis, the median seroprevalence of Leptospira, all serovars combined, was estimated to be 6.6% (95% probability interval (PI) 3.6–10.9%). Risk factors associated with seropositivity were assisting deer or cattle calving, farming deer, having ≥25% of flat terrain and high abundance of wild deer on farm, while high possum abundance on farm was negatively associated with seropositivity. No association was observed between farmer serostatus and previously recorded livestock serology. Leptospira seropositivity was associated with influenza‐like illness of farmers (RR = 1.7; 95% PI 1.0–2.5). Assuming a causal relationship, this suggested an annual risk of 1.3% (95% PI 0.0–3.0%) of influenza‐like illnesses due to Leptospira infection in the population of farmers. The association between seropositivity and disease can be used to estimate the public health burden of leptospirosis in New Zealand. Identifying and understanding risk factors for Leptospira seropositivity can inform preventive measures, hence contributing to the reduction of leptospirosis incidence in farmers.     

Clostridioides difficile on Ohio swine farms (2015): A comparison of swine and human environments and assessment of on‐farm risk factors

Swine are known reservoirs for Clostridioides difficile, formerly known as Clostridium difficile, and transmission from swine to human farm workers is strongly suggested by previous studies. This cross‐sectional study evaluated the potential role of farm environmental surfaces, including those in worker breakrooms and swine housing areas, in the possible transmission of C. difficile from swine to farm workers. Environmental surfaces and piglet faeces at 13 Ohio swine farms were sampled in 2015. Typical culturing techniques were performed to isolate C. difficile from samples, and amplification of toxin genes (tcdA, tcdB and cdtB) and PCR‐ribotyping were used to genetically characterize recovered isolates. In addition, sequencing of toxin regulatory gene, tcdC, was done to identify the length of identified deletions in some isolates. A survey collected farm‐level management risk factor information. Clostridioides difficile was recovered from all farms, with 42% (188/445) of samples testing positive for C. difficile. Samples collected from all on‐farm locations recovered C. difficile, including farrowing rooms (60%, 107/178), breakrooms (50%, 69/138) and nursery rooms (9%, 12/129). Three ribotypes recovered from both swine and human environments (078, 412 and 005) have been previously implicated in human disease. Samples taken from farrowing rooms and breakrooms were found to have greater odds of C. difficile recovery than those taken from nursery rooms (OR = 40.5, OR = 35.6, p < .001 respectively). Farms that weaned ≥23,500 pigs per year had lower odds of C. difficile recovery as compared to farms that weaned fewer pigs (OR = 0.4, p = .01) and weekly or more frequent cleaning of breakroom counters was associated with higher odds of C. difficile recovery (OR = 11.7, p < .001). This study provides important insights into the presence and characterization of C. difficile found in human environments on swine farms and highlights how these areas may be involved in transmission of C. difficile to swine farm workers and throughout the facility.     

Risk factors of Leptospira infection in Mediterranean periurban micromammals

Urbanization of natural areas can change abiotic factors, providing artificial sources of humidity in summer and decreasing variation of temperatures in winter. Our study aimed at document risk factors of infection in mammal reservoirs of pathogenic Leptospira in the human/wildlife interface of a large metropolitan area. We hypothesize that survival of Leptospira and thus their prevalence in animal reservoirs should be higher in residential areas than in natural habitats, especially after the hot, dry Mediterranean summers. We established the prevalence of Leptospira spp. and identified the serovars in 353 urine samples from micromammals (chiefly the wood mouse Apodemus sylvaticus, n = 266) using direct immunofluorescence and PCR. Animals were captured in spring and autumn, 2011–2012, in two natural parks and two adjacent residential areas in periurban Barcelona (NE Spain). Overall observed prevalence of infection was 11%, ranking between 8% and 13% in the better represented host species. We observed marked differences between seasons; the probability of finding a micromammal infected in spring was three times greater than in autumn (almost four times for wood mouse). Prevalence was not related with type of habitat, micromammal relative abundance or sex of the animal. Three Leptospira species were confirmed: Leptospira interrogans (47% of cases), Leptospira borgpetersenii (41%) and Leptospira kirschneri (12%). The serovars most commonly detected were those typically hosted by rodents, and serovars Ballum and Icterohemorrhagiae were the only ones found in autumn. People living in periurban Barcelona and those visiting the natural areas of the metropolitan area face hazard of infection with rodent‐borne Leptospira, especially during spring.     

Epidemiology and genetic diversity of zoonotic pathogens in urban rats (Rattus spp.) from a subtropical city,Guangzhou, southern China

Commensal rats (Rattus spp.), which are globally distributed, harbour many pathogens responsible for significant human diseases. Despite this, we have a poor understanding of the epidemiology and genetic diversity of some recently neglected zoonotic pathogens, such as Leptospira spp., Bartonella spp. and hepatitis E virus (HEV), which constitute a major public health threat. Thus, we surveyed the occurrences, co‐infection and genetic diversity of these pathogens in 129 urban rats from China. For Rattus tanezumi, the prevalences of Leptospira spp., Bartonella spp. and HEV infection were 6.67%, 0% and 46.67%, respectively. The prevalences of Leptospira spp., Bartonella spp. and HEV infection were 57.89%, 9.65% and 57.89% for Rattus norvegicus respectively. Leptospira spp. and HEV infections were more likely to occur in mature R. norvegicus. Phylogenetic analyses showed that pathogenic Leptospira interrogans and Leptospira borgpetersenii might exist. We also found that Bartonella spp. showed high similarity to Bartonella elizabethae, Bartonella rochalimae and Bartonella tribocorum, which are implicated in human disease. Dual and triple infections were both detected. Moreover, dual infections with Leptospira spp. and HEV represented the most frequent co‐infection, and there was a significantly positive association between them. High genetic diversity was observed in genes segments from Leptospira, Bartonella and HEV. Our results first discover the occurrence of multiple co‐infections and genetic diversity of Leptospira, Bartonella and HEV in commensal rats from China. Altogether, the present study provides an insight into evaluating the risk of rat‐borne zoonoses in urban China.     

Retracted: Risks of Avian Influenza (H5) in Duck Farms in the Ayeyarwaddy Delta Region,Myanmar

The Ayeyarwaddy delta region in the south‐west of Myanmar is the main agricultural and rice‐growing area. The region has a high density of duck and backyard chicken populations with low biosecurity. The objective of this study was to analyse risk factors for avian influenza (H5) in the Ayeyarwaddy delta region, Myanmar. A case–control risk factor study was conducted from April to June 2010 by individual interviews including risk factor questionnaires given to duck farmers (n = 50) in five townships in the Ayeyarwaddy delta region, Myanmar. Risk factor analyses were conducted using univariate analysis and multivariate logistic regression model with backward stepwise (wald) method. The results showed significant risk factors for AI (H5) sero‐positivity in ducks were wooden egg box containers (OR = 52.7, 95% CI = 2.34–1188, P = 0.013) and water sourced from wetlands (OR = 30.7, 95% CI = 1.96–481.6, P = 0.015). Conversely, the cleaning of reusable egg containers was determined as a protective factor (OR = 0.03, 95% CI = 0.00–0.42, P = 0.01). In conclusion, this study identified risk factors for AI (H5) in duck farms and the importance of avian influenza prevention and control.     

The Effectiveness of Coxiella burnetii Vaccines in Occupationally Exposed Populations: A Systematic Review and Meta‐Analysis

To estimate the effect of vaccination in preventing acute Q fever in individuals occupationally exposed to Coxiella burnetii, a systematic review and meta‐analysis were undertaken in controlled trials and observational studies. Publications were obtained through a scoping study of English and non‐English articles, and those reporting a commercially licensed or licensable vaccine compared with an unvaccinated or placebo control group were included in the review. Two authors performed independent assessment of risk of systematic error and data extraction. One controlled trial and five cohort publications met the inclusion criteria. All trials used a Henzerling phase I vaccine. A random‐effects meta‐analysis estimated significant protection in abattoir workers (RR = 0.07; 95% confidence interval [CI] 0.02–0.22) compared with the control individuals. In individuals with rare or sporadic contact with the abattoir, a significant benefit of vaccination was also found (RR = 0.06; 95% CI 0–0.93). Overall, the vaccine effectively prevented acute Q fever in individuals responsible for handling animals or their products and those working in the abattoir but not directly exposed to animals (RR = 0.06; 95% CI 0.02–0.18). Caution must be taken when interpreting the effect of C. burnetii vaccination as significant heterogeneity amongst publications was observed. A meta‐regression found no significant univariate associations. This may reflect the uncertainty provided by reported data in the cohort publications. Potential systematic biases were present in the publications, and evidence included may not be sufficiently robust to extrapolate the effect of vaccination on occupationally exposed groups beyond the population of abattoir employees in Australia where all included studies occurred.     

Personal and household factors involved in recent Rickettsia exposure in a rural population from Yucatán,Mexico

The aim of the study was to describe the epidemiological factors associated with the risks of recent Rickettsia exposure in inhabitants of a rural population from Yucatán, Mexico. The study included 130 inhabitants from Maxcanú, Yucatán. Blood samples were collected to detect IgM and IgG antibodies against Rickettsia typhi and Rickettsia rickettsii by an indirect immunofluorescence antibody test. Additionally, nested polymerase chain reaction was performed to amplify fragments of the 17kDa and sca5 genes. Previously, an epidemiological questionnaire was applied focused on collecting information on personal and housing exposure variables related to the recent infection with Rickettsia to determine epidemiological associations. Results that exhibited a p‐value < .25 were included in a generalized multinomial logistic linear model to determine the variables involved with the risk of contact or Rickettsia infection. In all, 76% (99/130) of the participants presented with immunoglobulin titres against the Rickettsia species evaluated, while rickettsial DNA was detected in 35.4% (46/130) of the participants. The association analysis with the personal exposure variables showed that the productive age group (OR = 0.32; 95% CI = 0.10–1.03) and the elders group (OR = 0.12; 95% CI = 0.01–0.83) were protective factors for recent infection with R. typhi, taking as reference the school group. The presence of a family orchard in the home (OR = 7.56; 95% CI = 1.62–35.29) was a risk factor for recent infection with R. rickettsii. Presumably, the presence of ectoparasites (OR = 2.71; 95% CI = 0.90–8.09) at home was a risk factor for recent infection with both Rickettsia species. Recent infection was demonstrated in inhabitants from Maxcanú, Yucatán. A high seropositive frequency was obtained. The results highlight the importance of the family garden and the presence of ectoparasites in the home as risk factors associated with recent infection with Rickettsia in inhabitants from Maxcanú.     

Risk of zoonotic transmission of swine influenza at the human–pig interface in Guangdong Province,China

A cross‐sectional survey was conducted from 2015 to 2018 to assess the risk of zoonotic influenza to humans at the human–pig interface in Guangdong Province, south China. One hundred and fifty‐three pig farmers, 21 pig traders and 16 pig trade workers were recruited using convenience sampling and surveyed at local pig farms, live pig markets and slaughterhouses, respectively. Questionnaires were administered to collect information on the biosecurity and trading practices adopted and their knowledge and beliefs about swine influenza (SI). Most (12 of 16) trade workers said they would enter piggeries to collect pigs and only six of 11 said they were always asked to go through an on‐farm disinfection procedure before entry. Only 33.7% of the interviewees believed that SI could infect humans, although pig farmers were more likely to believe this than traders and trade workers (p < .01). Several unsafe practices were reported by interviewees. ‘Having vaccination against seasonal flu’ (OR = 3.05, 95% CI: 1.19–8.93), ‘Believe that SI can cause death in pigs’ (no/yes: OR = 8.69, 95% CI: 2.71–36.57; not sure/yes: OR = 4.46, 95% CI: 1.63–14.63) and ‘Keep on working when getting mild flu symptoms’ (OR = 3.80, 95% CI: 1.38–11.46) were significantly and positively correlated to ‘lacking awareness of the zoonotic risk of SI’. ‘Lacking awareness of the zoonotic risk of SI’ (OR = 3.19, 95% CI: 1.67–6.21), ‘Keep on working when getting mild flu symptoms’ (OR = 3.59, 95% CI: 1.57–8.63) and ‘Don't know SI as a pig disease’ (OR = 3.48, 95% CI: 1.02–16.45) were significantly and positively correlated to ‘not using personal protective equipment when contacting pigs’. The findings of this study would benefit risk mitigation against potential pandemic SI threats in the human–pig interface in China.     

Seroprevalence and potential risk of bovine brucellosis in zerograzing and pastoral dairy systems in Uganda

A cross-sectional study was conducted in Uganda between November 2006 and February 2007 to assess the seroprevalence and risk of brucellosis in zerograzing and pastoral dairy systems; two major sources of milk in Uganda, 80% of which is sold unpasteurized to consumers through informal channels. A total of 723 cattle comprised of 497 animals from the pastoral system and 226 animals from the zerograzing system were tested for antibodies against natural B. abortus infection using the competitive enzyme-linked immunosorbent assay (C-ELISA). Herd-level seroprevalence was 100% in the pastoral system and 5.5% (95% CI: 1.8, 9.2) in the zerograzing system. The animal-level seroprevalence and within-herd range of brucellosis in cattle in the pastoral system were 34.0% (95% CI: 29.9, 38.1) and 8.1–75.9%, while for those in the zerograzing system were 3.3% (95% CI: 0.9, 5.7) and 0–9.0%. Abortion rates of 23% and 0% among seropositive cows vis-à-vis 5.4% and 1.9% among seronegative cows were recorded in the pastoral and zerograzing systems, respectively. The risk of natural B. abortus infection was higher among older cattle (>24 m) (Odds ratio [OR] = 1.83, 95% CI: 1.25–2.67) and dry cows (OR = 2.01, 95% CI: 1.23–3.31) in the pastoral system, and in calves aged 0–6 m (OR = 5.72, 95% CI: 1.04–31.41) in the zerograzing system. Implementing a culling program in the zerograzing system to eliminate the existing low risk of brucellosis and targeting calves in the pastoral systems for vaccination could avert the cost-related limitation of brucellosis control in Uganda.     

Coxiella burnetii seroprevalence in unvaccinated veterinary workers in Australia: Evidence to support Q fever vaccination

Q fever (caused by Coxiella burnetii) is a serious zoonotic disease that occurs almost worldwide. Occupational contact with animals increases the risk of exposure, and Q fever vaccination is recommended for veterinary workers in Australia. This study aimed to investigate C. burnetii seroprevalence among unvaccinated veterinary workers in Australia and determine factors associated with a positive serological result. During 2014 and 2015, convenience sampling at veterinary conferences and workplace vaccination clinics was undertaken. Participants completed a questionnaire and provided a blood sample for C. burnetii serology. Participants were predominantly veterinarians (77%), but veterinary support staff, animal scientists, and administration workers also participated. Blood samples (n = 192) were analysed by an immunofluorescence assay and considered positive where the phase I or phase II IgG titre was ≥1/50. Seroprevalence was 19% (36/192; 95% CI 14%–25%). A positive serological result was significantly associated with (a) working in outer regional/remote areas (odds ratio [OR] 6.2; 95% CI 1.9–20.8; reference = major cities; p = .009) and (b) having spent more than 50% of total career working with ruminants (OR 4.8; 95% CI 1.7–13.5; reference = <15% of career; p = .025). These findings confirm an increased risk of exposure to C. burnetii compared to the general population, providing new evidence to support Q fever vaccination of veterinary workers in Australia.     

Predictors for Risk Factors for Spread of Avian Influenza Viruses by Poultry Handlers in Live bird markets in Uganda

Live bird markets (LBMs) are essential for marketing poultry, but have been linked to many outbreaks of avian influenza (AI) and its spread. In Uganda, it has been observed that demographic characteristics of poultry traders/handlers influence activities and decision‐making in LBMs. The study investigated the influence of socio‐demographic characteristics of poultry handlers: age, sex, religion, educational background, level of income, location of residence and region of operation on 20 potential risk factors for introduction and spread of AI in LBMs. Study sites included 39 LBMs in the four regions of Uganda. Data was collected using a semi‐structured questionnaire administered to 424 poultry handlers. We observed that background of education was a predictor for slaughter and processing of poultry in open sites. Location of residence was associated with slaughter of poultry from open sites and selling of other livestock species. Region influenced stacking of cages, inadequate cleaning of cages, feeders and drinkers, and provision of dirty feed and water. Specifically, bird handlers with secondary level of education (OR = 12.9, 95% CI: 2.88–57.4, P < 0.01) were more likely to be involved in open site slaughter of poultry than their counterparts without formal education. Comparatively, urbanite bird handlers were less likely to share poultry equipment (OR = 0.4, 95% CI: 0.22–0.63, P < 0.01) than rural resident handlers. Poultry handlers in Northern were 3.5 times more likely to practise insufficient cleaning of cages (OR = 3.5, 95% CI: 1.52–8.09) compared to those in Central region. We demonstrated that some socio‐demographic characteristics of poultry handlers were predictors to risky practices for introduction and spread of AI viruses in LBMs in Uganda.     

Serological Survey of Veterinarians to Assess the Zoonotic Potential of Three Emerging Swine Diseases in Mexico

We conducted an immunological assay of blood samples taken from 85 swine‐specialist veterinarians attending the Congress of the Mexican Association of Swine Specialist Veterinarians in Mexico in 2011. Serum samples were assayed for Porcine rubulavirus (PorPV), Encephalomyocarditis virus (EMCV) and Leptospira spp. antibodies. Using a hemagglutination inhibition test, we registered 2.3% and 27% seropositivity for PorPV and EMCV, respectively. Using viral neutralization tests, we registered 5.8% and 47% seropositivity for PorPV and EMCV, respectively. For Leptospira spp., we registered a seropositivity of 38.8%. The variables (sex, age, years of exposure, number of visited farms, biosecurity level and region) showed no significant effect (P > 0.05) on the seropositivity for EMCV, PorPV and Leptospira spp. except for number of visited farms on HI seropositivity for EMCV (P < 0.05; odds ratio: 1.38). The data obtained provide information on the epidemiology of emerging diseases with zoonotic potential in occupational risk groups.     

A cross‐sectional study of intestinal parasitoses in dogs and children of the periurban area of La Plata (Buenos Aires,Argentina): Zoonotic importance and implications in public health

A cross‐sectional study was performed between school term dates 2014 and 2015 to diagnose intestinal parasites in dogs and children living with them. The socio‐environmental characteristics and hygiene practices of the children were also evaluated in terms of risk factors for parasitic infection of periurban neighbourhoods of La Plata (Buenos Aires, Argentina). Serial coproparasitological samples of 78 dogs and 211 children were analysed by means of concentration and flotation techniques. Socio‐environmental variables and hygiene practices of children were evaluated through semi‐structured questionnaires which were answered by every family. The study showed that 82.1% of dogs were parasitized. The specific richness was of 11 species; Ancylostoma caninum (69.2%), Uncinaria stenocephala (41.0%), Trichuris vulpis (28.2%) and Toxocara canis (21.8%) were the most prevalent. The study also revealed that 67.8% of children were positive. Also, 11 species were identified and the most prevalent were Blastocystis sp. (36.0%), Enterobius vermicularis (27.5%) and Giardia lamblia (21.3%). The risk for parasitosis was higher in 6‐year‐old children and older (OR = 1.9, 95% IC: 1.0–3.7) and in those who did not wash their hands or did it occasionally after playing with their pets (OR = 2.8, 95% IC: 1.4–5.5). Blastocystis sp. and Entamoeba coli infection risks were greater in children whose parents had a basic level of education (OR = 3.4, 95% IC: 1.3–8.7 and OR = 3.6, 95% IC: 0.8–15.9, respectively). In addition, the risk of infection for E. coli was higher in children who lived in floodable houses (OR = 4.4, 95% IC: 0.9–16.6). Likewise, the risk of infection for E. vermicularis was greater in children with onychophagia (OR = 1.6, 95% IC: 0.7–3.7) and in 6 year olds and older whose parents completed only primary studies (OR = 3.6, 95% IC: 1.4–9.1). The results obtained show the existence of a worrying epidemiological scenario that stresses the importance of zoonotic parasitosis as a serious problem of public health.     

Reduced Burden of Salmonella enterica in Bovine Subiliac Lymph Nodes Associated with Administration of a Direct‐fed Microbial

Despite effective food safety interventions within abattoirs, Salmonella enterica remains a common contaminant of raw ground beef. Research has recently implicated peripheral lymph nodes (PLNs) as a potential route by which Salmonella contaminates ground beef. This study examined the efficacy of using Lactobacillus animalis (formerly designated Lactobacillus acidophilus; NP51) and Propionibacterium freudenreichii (NP24), at 10⁹ cfu/head/day, as a direct‐fed microbial (DFM) in feedlot cattle diets to control Salmonella within PLNs. Two studies were conducted in which cattle were randomly allocated into either control or DFM treatment groups. Diets of treated cattle were supplemented with 10⁹ cfu/head/day of the DFM, while control groups received no DFM supplementation. During slaughter at abattoirs, one subiliac lymph node (SLN) per carcass was collected from 627 carcasses from one study and 99 carcasses from the second study. Lymph nodes were cultured to estimate the presence and concentration of Salmonella. In the first study, effects of DFM supplementation varied across slaughter days. On the first and second slaughter days, prevalence was reduced by 50% (P = 0.0072) and 31% (P = 0.0093), respectively. No significant difference was observed on slaughter day three (P = 0.1766). In the second study, Salmonella was 82% less likely (P = 0.008) to be recovered from SLNs of treatment cattle. While a greater relative risk reduction was observed in the latter study, absolute risk reductions were similar across studies. A significant reduction in the concentration of Salmonella in SLNs (P < 0.0001) on a cfu/g and cfu/node basis was also observed in cattle administered NP51 and NP24 in the first study; in the second study, too few quantifiable SLNs were observed to facilitate meaningful comparisons. The results indicate that NP51 and NP24 supplementation may aid in reducing the prevalence and concentration of Salmonella in SLNs and, therefore, serve as an effective control measure to reduce Salmonella in ground beef products.     

Effects of dietary crude protein and tannic acid on nitrogen excretion,urinary nitrogenous composition and urine nitrous oxide emissions in beef cattle

Two consecutive trials were carried out to study the effects of dietary crude protein (CP) and tannic acid (TA) on nitrogen (N) metabolism of beef cattle and consequently, the N₂O emissions from the urine of cattle. In Trial I, eight growing castrated cattle were used as the experimental animals. Two levels of dietary CP (110.6 and 135.7 g/kg dry matter [DM]) and two levels of TA (0 and 16.9 g/kg DM) were allocated in a replicated 2 × 2 crossover design. In Trial II, the N₂O emissions from the urine of cattle collected from Trial I were determined using the static incubation technique. An interaction between dietary CP and TA on the urinary N excretion (p < .05) was found but not on the N₂O‐N emission of cattle urine. Increasing dietary CP level from 110.6 g/kg DM to 135.7 g/kg DM increased the total N excretion (p < .001), the N retention (p < .05) and the ratio of urinary urea‐N/urinary N (p < .01), did not affect the N use efficiency (NUE; p > .05) and shifted the N excretion from faeces to urine. Increasing the dietary CP level increased the N₂O‐N emission of cattle urine. Dietary addition of TA decreased the urinary excretions of urea (p < .001) and shifted the N excretion from urine to faeces, did not affect the NUE of beef cattle (p > .10), and decreased the N₂O‐N emission of cattle urine. Pyrogallol and resorcinol of the TA metabolites were detected in urine with dietary addition of TA. Feeding beef cattle with relatively low CP level and adding TA in rations are effective approaches to mitigate the N₂O‐N emissions from cattle urine.     

Major metacestodes in cattle slaughtered at Wolaita Soddo Municipal abattoir,Southern Ethiopia: Prevalence,cyst viability,organ distribution and socioeconomic implications

A cross sectional study to determine the prevalence and socioeconomic importance of major metacestodes of cattle was conducted from November 2007 to April 2008 at Wolaita Soddo abattoir. Accordingly, of 415 randomly selected slaughtered cattle, 11.3% and 15.4% were infected with Cysticercus bovis and hydatid cysts, respectively. The anatomical distributions of these parasites include various organs. The major risk factors for cysticercosis prevalence were origin of the animals (P < 0.001, OR = 7.3) and breeds (P = 0.004, OR = 4.3), and hydatid cysts prevalence was significantly varied with different origins (P = 0.021, OR = 2.8). The viability of C. bovis was higher (28.3%) than that of hydatid cyst (1.7%). Of 79 interviewed respondents, 50.63% had acquired taeniasis and analysis of the risk factors showed association of religions (P = 0.003, OR = 24.4), occupation (P < 0.001, OR = 6.9), educational background (P = 0.035, OR = 2.7) and age (P < 0.001, OR = 3.9) of the respondents with taeniasis prevalence. Furthermore, the inventory of taeniasis drugs dose and treatment cost were estimated to be 335,772 adult doses and 93,310 USD. In conclusion, the findings of the present study imply the zoonotic and socioeconomic importance of the diseases, which need intervention.