Public health significance of Helicobacter pullorum, a putative food-associated emerging zoonotic pathogen in Iran.

According to the World Health Organization, diseases which are naturally transmissible from vertebrate animals to human beings or from humans to vertebrates are defined as the zoonotic diseases. Among the most common zoonotic pathogens, Helicobacter pullorum has earned public recognition regarding its public health significance. This Enterohepatic Helicobacter species has been shown to be a very dangerous and life-threatening microorganism, accounting for several clinically important infections in the human population. However, despite the several studies indicating the significance of H.pullorum in both humans and animals, there is a lack of documented information and reliable statistics about this pathogen throughout the world. Thus, in this review, we would provide a novel knowledge about the general characteristics, isolation methods, host ranges and transmission routes, and occurrences of H.pullorum in poultry, chicken meat, and human in Iran. We would also clarify the status of antimicrobial resistance (AMR) profile of the H.pullorum isolates from various samples in this country.

The role of small ruminants in the epidemiology of leptospirosis.

Leptospirosis is a common global zoonotic disease of man and all farm animals. Although most leptospiral infections in sheep and goats are asymptomatic, they may play a role in the epidemiology of the disease by the spread of Leptospira through the urine. This study was carried out to evaluate the role of sheep and goats in the epidemiology of leptospirosis. Blood and urine samples were taken from 210 goats and 246 sheep. To detect antibodies, sera samples were tested with 8 live serovars of L. interrogans (Hardjo, Pomona, Grippotyphosa, Canicola, Ballum, Icterhemorrhagiae, Tarasovi, and Australis) by MAT. Then, urine samples were tested by Nested PCR targeting 16S rRNA gene for detection of pathogenic Leptospira. Results of MAT showed that 10.95% of goats and 8.53% of sheep had antibodies against at least one examined serovars. In both species, the highest reacting was L. i. Pomona with a rate of 68.18% and 56% in sheep and goats, respectively. Moreover, in PCR, 2 (0.95%) urine samples of goat and 12 (4.87%) urine samples of sheep were positive. All of the MAT positive studied animals were PCR negative and, statistical analysis showed that there was no relationship and agreement between the results of PCR and MAT in sheep (kappa = - 0.07, p > 0.05) and goats (kappa = - 0.02, p > 0.05). Finally, it is concluded that sheep and goats can excrete L. interrogans in the urine and thus transmit them to other animals and humans.

Ocorrência de sorogrupos/sorovares de Leptospira spp. em cães com suspeita clínica de leptospirose em Santa Maria ­ RS / Occurrence of serogroups/serovars of Leptospira spp. in dogs with clinical suspicion of leptospirosis in Santa Maria ­ RS

A leptospirose é uma zoonose de distribuição mundial que pode acometer cães e ser altamente letal para a espécie. No Brasil, tal enfermidade tem caráter endêmico na espécie canina e configura-se como um sério problema de saúde pública. Objetivou-se verificar a ocorrência dos sorogrupos/sorovares de Leptospira spp. que mais acometem cães com suspeita clínica de leptospirose na cidade de Santa Maria ­ RS, Brasil, analisando sua titulação de anticorpos. No estudo, utilizou-se os laudos dos exames de soroaglutinação microscópica (SAM) para leptospirose de 218 cães provenientes da cidade de Santa Maria ­ RS durante o período de janeiro de 2015 a dezembro de 2019. Todos os laudos foram emitidos pelo Laboratório de Leptospirose (LabLepto - UFSM). Das 218 amostras de soro processadas nos cinco anos, 101 (46,33%) resultaram positivas para, pelo menos, um sorogrupo/sorovar testado. Este estudo demonstrou maior ocorrência do sorogrupo Icterohaemorrhagiae (53,37%) contemplado pelas sorovares Copenhageni e Icterohaemorrhagiae, com 49 (30,06%) e 38 (23,31%) soros reagentes, respectivamente. As titulações variaram de 100 a 6400, sendo que a mais recorrente encontrada nas amostras deste estudo foi 100, representando 47,85% dos títulos de anticorpos. Os dados obtidos neste estudo são de grande valia para o conhecimento dos sorogrupos/sorovares circulantes na região e sua epidemiologia podendo, inclusive, auxiliar para futuras formulações vacinais considerando sorogrupos/sorovares mais frequentemente detectados, contribuindo, assim, com a saúde pública.

Leptospirosis is a worldwide distribution zoonosis that can affect dogs and be highly lethal for the species. In Brazil, this disease is endemic in the canine species and represents a serious public health problem. The aim of this study was to verify the occurrence of Leptospira spp. that most affect dogs with clinical suspicion of leptospirosis in the city of Santa Maria ­ RS, Brazil, analyzing their antibody titers. In the study, we used the reports of microscopic agglutination tests (MAS) for leptospirosis in 218 dogs from the city of Santa Maria - RS during the period from January 2015 to December 2019. All reports were issued by the Leptospirosis Laboratory (LabLepto - UFSM). Of the 218 serum samples processed over the five years, 101 (46.33%) were positive for at least one serogroup/serovar tested. This study showed a higher occurrence of serogroup Icterohaemorrhagiae (53.37%) covered by serovars Copenhageni and Icterohaemorrhagiae, with 49 (30.06%) and 38 (23.31%) reagent sera, respectively. The titers ranged from 100 to 6400, and the most recurrent found in the samples in this study was 100, representing 47.85% of the antibody titers. The data obtained in this study are of great value for understanding the serogroups/serovars circulating in the region and their epidemiology, and may even contribute to future vaccine formulations considering the most frequently detected serogroups/serovars, thus contributing to public health.

Cluster of human Salmonella Guinea infections: Reported reptile exposures and associated opportunities for infection prevention - Ohio, 2019-2020.

A cluster of five human Salmonella Guinea cases was identified among Ohio residents through core genome multilocus sequence typing of clinical isolates. An investigation was conducted to characterize illnesses and identify common exposures. Four patients were aged ≤5 years and three of four patients with information available regarding exposure to animals reported prior exposure to bearded dragons. Practices that potentially increased the risk for Salmonella transmission from reptiles to humans included allowing pet reptiles to roam freely in the home, cleaning reptile habitats indoors, and kissing reptiles. These findings prompted a multistate investigation that resulted in the identification of additional closely related Salmonella Guinea isolates from patients across multiple states. The investigation of cases in Ohio and information shared by other states indicated the potential association between human Salmonella Guinea infections and reptiles, particularly bearded dragons. To prevent Salmonella transmission from reptiles, continued educational efforts should address pet owners and focus on specific reptile ownership practices.

Epidemiology of leptospirosis in Tanzania: A review of the current status, serogroup diversity and reservoirs.

BACKGROUND: Tanzania is among the tropical countries of Sub-Saharan Africa with the environmental conditions favorable for transmission of Leptospira. Leptospirosis is a neglected zoonotic disease, and although there are several published reports from Tanzania, the epidemiology, genetic diversity of Leptospira and its host range are poorly understood. METHODS: We conducted a comprehensive review of human and animal leptospirosis within the 26 regions of the Tanzanian mainland. Literature searches for the review were conducted in PubMed and Google Scholar. We further manually identified studies from reference lists among retrieved studies from the preliminary search. RESULTS: We identified thirty-four studies describing leptospirosis in humans (n = 16), animals (n = 14) and in both (n = 4). The number of studies varied significantly across regions. Most of the studies were conducted in Morogoro (n = 16) followed by Kilimanjaro (n = 9) and Tanga (n = 5). There were a range of study designs with cross-sectional prevalence studies (n = 18), studies on leptospirosis in febrile patients (n = 13), a case control study in cattle (n = 1) and studies identifying novel serovars (n = 2). The most utilized diagnostic tool was the microscopic agglutination test (MAT) which detected antibodies to 17 Leptospira serogroups in humans and animals. The Leptospira serogroups with the most diverse hosts were Icterohaemorrhagiae (n = 11), Grippotyphosa (n = 10), Sejroe (n = 10), Pomona (n = 9) and Ballum (n = 8). The reported prevalence of Leptospira antibodies in humans ranged from 0.3-29.9% and risk factors were associated with occupational animal contact. Many potential reservoir hosts were identified with the most common being rodents and cattle. CONCLUSION: Leptospirosis is prevalent in humans and animals in Tanzania, although there is regional and host variation in the reports. Many regions do not have information about the disease in either humans or their animal reservoirs. More studies are required to understand human leptospirosis determinants and the role of livestock in leptospirosis transmission to humans for the development of appropriate control strategies.

Genomic insights into Salmonella Choleraesuis var. Kunzendorf outbreak reveal possible interspecies transmission.

Salmonella enterica serovar Choleraesuis is a host-adapted serovar that causes serious infections in domestic pigs and wild boars. Here, we investigated an outbreak of salmonellosis in domestic pigs in Slovenia, 2018-2019. To assess the outbreak, 18 isolates from domestic pigs, wild boars, wild boar meat and a human patient underwent whole-genome sequencing (WGS). All isolates were of sequence type (ST) 145 and harbored no antimicrobial resistance genes or AMR-associated mutations. A single transmission cluster (≤ 6 alleles) of spatially (< 100 km) and temporally linked isolates was observed, comprising isolates of pig (n = 9), wild boar (n = 2) and human (n = 1) origin, and suggesting possible interspecies transmission. In all outbreak-related animal cases, septicemic salmonellosis was observed, accompanied in some cases by enteric symptoms. All pig isolates were linked to a single intensive breeding farm that distributed growers to small family farms. The same transport vehicles were used to distribute growers to family farms and also to transport livestock between neighboring countries. Both isolates that originated from the imported wild boar meat were genetically distant (≥ 122 alleles) from the outbreak cluster. The present results indicate the importance of screening domestic pigs and proper disinfection of transport vehicles to control the spread of S. Choleraesuis.

Characteristics of the 100 largest modern zoonotic disease outbreaks.

Zoonotic disease outbreaks are an important threat to human health and numerous drivers have been recognized as contributing to their increasing frequency. Identifying and quantifying relationships between drivers of zoonotic disease outbreaks and outbreak severity is critical to developing targeted zoonotic disease surveillance and outbreak prevention strategies. However, quantitative studies of outbreak drivers on a global scale are lacking. Attributes of countries such as press freedom, surveillance capabilities and latitude also bias global outbreak data. To illustrate these issues, we review the characteristics of the 100 largest outbreaks in a global dataset (n = 4463 bacterial and viral zoonotic outbreaks), and compare them with 200 randomly chosen background controls. Large outbreaks tended to have more drivers than background outbreaks and were related to large-scale environmental and demographic factors such as changes in vector abundance, human population density, unusual weather conditions and water contamination. Pathogens of large outbreaks were more likely to be viral and vector-borne than background outbreaks. Overall, our case study shows that the characteristics of large zoonotic outbreaks with thousands to millions of cases differ consistently from those of more typical outbreaks. We also discuss the limitations of our work, hoping to pave the way for more comprehensive future studies. This article is part of the theme issue 'Infectious disease macroecology: parasite diversity and dynamics across the globe'.

First report of Borrelia burgdorferi sensu stricto detection in a commune genospecies in Apodemus agrarius in Gwangju, South Korea.

Lyme disease is a tick-borne infectious disease caused by the Borrelia burgdorferi sensu lato complex. However, the distribution of Borrelia genospecies and the tissue detection rate of Borrelia in wild rodents have rarely been investigated. Here, we studied 27 wild rodents (Apodemus agrarius) captured in October and November 2016 in Gwangju, South Korea, and performed nested polymerase chain reaction targeting pyrG and ospA to confirm Borrelia infection. Eight rodents (29.6%) tested positive for Borrelia infection. The heart showed the highest infection rate (7/27; 25.9%), followed by the spleen (4/27; 14.8%), kidney (2/27; 7.4%), and lungs (1/27; 3.7%). The B. afzelii infection rate was 25.9%, with the highest rate observed in the heart (7/27; 25.9%), followed by that in the kidney and spleen (both 2/27; 7.4%). B. garinii and B. burgdorferi sensu stricto were detected only in the spleen (1/27; 3.7%). This is the first report of B. burgdorferi sensu stricto infection in wild rodents in South Korea. The rodent hearts showed a high B. afzelii infection rate, whereas the rodent spleens showed high B. garinii and B. burgdorferi sensu stricto infection rates. Besides B. garinii and B. afzelii, B. burgdorferi sensu stricto may cause Lyme disease in South Korea.

Ongoing Outbreak of Extensively Drug-Resistant Campylobacter jejuni Infections Associated With US Pet Store Puppies, 2016-2020.

Importance: Extensively drug-resistant Campylobacter jejuni infections cannot be treated with any commonly recommended antibiotics and pose an increasing public health threat. Objectives: To investigate cases of extensively drug-resistant C jejuni associated with pet store puppies and describe the epidemiologic and laboratory characteristics of these infections. Design, Setting, and Participants: In August 2017, health officials identified, via survey, patients with C jejuni infections who reported contact with puppies sold by pet stores. In conjunction with state and federal partners, the Centers for Disease Control and Prevention investigated cases of culture-confirmed C jejuni infections in US patients with an epidemiologic or molecular association with pet store puppies between January 1, 2016, and February 29, 2020. Available records from cases occurring before 2016 with genetically related isolates were also obtained. Main Outcomes and Measures: Patients were interviewed about demographic characteristics, health outcomes, and dog exposure during the 7 days before illness onset. Core genome multilocus sequence typing was used to assess isolate relatedness, and genomes were screened for resistance determinants to predict antibiotic resistance. Isolates resistant to fluoroquinolones, macrolides, and 3 or more additional antibiotic classes were considered to be extensively drug resistant. Cases before 2016 were identified by screening all sequenced isolates submitted for surveillance using core genome multilocus sequence typing. Results: A total of 168 patients (median [interquartile range] age, 37 [19.5-51.0] years; 105 of 163 female [64%]) with an epidemiologic or molecular association with pet store puppies were studied. A total of 137 cases occurred from January 1, 2016, to February 29, 2020, with 31 additional cases dating back to 2011. Overall, 117 of 121 patients (97%) reported contact with a dog in the week before symptom onset, of whom 69 of 78 (88%) with additional information reported contact with a pet store puppy; 168 isolates (88%) were extensively drug resistant. Traceback investigation did not implicate any particular breeder, transporter, distributer, store, or chain. Conclusions and Relevance: Strains of extensively drug-resistant C jejuni have been circulating since at least 2011 and are associated with illness among pet store customers, employees, and others who come into contact with pet store puppies. The results of this study suggest that practitioners should ask about puppy exposure when treating patients with Campylobacter infection, especially when they do not improve with routine antibiotics, and that the commercial dog industry should take action to help prevent the spread of extensively drug-resistant C jejuni from pet store puppies to people.

Emerging MDR-Mycobacterium avium subsp. avium in house-reared domestic birds as the first report in Egypt.

BACKGROUND: Avian tuberculosis is a chronic and zoonotic disease that affects a wide variety of birds, mammals, and humans. This study aimed to estimate the frequency of Mycobacterium avium subsp. avium in some domestic birds based on molecular diagnosis, antibiogram profile, and PCR-based detection of inhA, rpoB, rpsL, and otrB antibiotic resistance-related genes. METHODS: A total of 120 fecal samples were collected from small flocks of house-reared domestic birds at Ismailia Governorate, Egypt. The collected samples were processed and subjected to the bacteriological examination. The antimicrobial susceptibility testing of the recovered isolates was performed using the broth microdilution method for the detection of minimum inhibitory concentrations (MICs). The genetic detection of the IS901confirmatory gene, inhA, rpoB, rpsL, and otrB genes was carried out using PCR. RESULTS: The frequency of M. avium subsp. avium was 4.1% (5/120); 10% (4/40) in ducks, and 2.5% (1/10) in geese. The identification of the recovered isolates was confirmed using PCR, where all the tested isolates were positive for IS901confirmatory gene. The results of the broth microdilution method revealed that most of the recovered isolates exhibited multidrug resistance (MDR) to isoniazid, rifampicin, streptomycin, oxytetracycline, and doxycycline, and harbored the inhA, rpoB, rpsL, and otrB genes. CONCLUSION: In brief, to the best of our knowledge this is the first report that emphasized the emergence of avian tuberculosis in house-reared domestic birds in Egypt. The emergence of MDR- M. avium subsp. avium is considered a public health threat. Emerging MDR-M. avium subsp. avium in domestic birds are commonly harbored the IS901, inhA, rpoB, rpsL, and otrB genes. Azithromycin and clofazimine revealed a promising in-vitro antibacterial activity against M. avium subsp. avium.

Zoonotic vector-borne bacteria in wild rodents and associated ectoparasites from Tunisia.

Wild rodents are considered as potential carriers of several zoonotic vector-borne bacteria but their epidemiology is poorly understood in Tunisia. A total of 305 biological samples (100 spleens, 100 livers, 100 kidneys, and 5 pooled ectoparasites (Xenopsylla cheopis, Laelaps echidninus, Ornithonyssus sp., Hoplopleura sp. and eggs of the rat fleas)) were collected from 100 wild rodents from three Tunisian governorates. Molecular screening was performed to reveal infections with main vector-borne bacteria. Captured rodents belonged to three rodent genera and species including Rattus rattus (n = 51, 51%), Meriones shawi (n = 24, 24%) and Mus musculus (n = 25, 25%). Examined rodents were found to be heavily infested by the rat flea X. cheopis (n = 32, 47%) and the rat mite L. echidninus (n = 22, 32.3%). However, the rat mite Ornithonyssus sp. (n = 13, 19.1%) and the rat lice Hoplopleura sp. (n = 1, 1.5%) were rarely identified. Based on 16S rRNA and msp4 genes, infection with Anaplasmataceae bacteria was detected in six specimens of R. rattus and one M. shawi. Pathogenic A. phagocytophilum (n = 1), A. phagocytophilum-like 1 (Anaplasma sp. Japan) (n = 1), and A. ovis (n = 5) were identified. On the basis of ompB, ompA and gltA genes, infection with Rickettsia spp. was identified in three specimens of R. rattus and one of M. shawi. Five Rickettsia species of the spotted fever group, corresponding to R. monacensis, R. helvetica, R. massiliae, R. africae, and R. aeschlimannii, were detected in mixed infections. Bartonella henselae DNA was also found in two R. rattus, based on rpoB partial sequences. All revealed Anaplasma, Rickettsia and Bartonella bacteria were detected in spleen samples. Ehrlichia, Coxiella and Borrelia spp. were not identified in any of the tested samples. In Tunisia, this is the first report indicating infections with Anaplasma, Rickettsia and Bartonella spp. in wild rodents, particularly present alongside domestic livestock and human. This represents a serious risk of potential bacterial transmission. Thus, controlling rodent population in animal herds, residential areas and sensitizing local people to this risk seem absolutely necessary.

Clinical Presentations of Brucellosis Over a Four-Year Period at Sultan Qaboos University Hospital and Armed Forces Hospital, Muscat, Oman.

OBJECTIVES: Brucellosis is a highly contagious zoonotic disease which can have serious health implications for affected humans and livestock. This study aimed to evaluate the clinical presentation, geographical distribution and risk factors of brucellosis cases admitted over a four-year period to two hospitals in Muscat, Oman. METHODS: This observational study was conducted from January 2015 to December 2018 at the Sultan Qaboos University Hospital and Armed Forces Hospital in Muscat. All patients with probable or definitive diagnoses of brucellosis according to the diagnostic criteria of the World Health Organization were included. Relevant data were gathered from the patients' medical records, including results from standard agglutination tests, Brucella enzyme-linked immunosorbent assays, bacterial blood or tissue/aspirate cultures and Brucella polymerase chain reaction tests. RESULTS: A total of 64 patients were diagnosed with brucellosis over the study period. The median age was 31.5 years and 73.4% were male. The majority (95.2%) presented with fever, followed by weight loss (51%), transaminitis (48.4%), peripheral arthritis/arthralgia (15.9%) and back pain (spondylodiscitis/sacroiliitis; 23.4%). Overall, 75.5% reported having consumed raw dairy products, while only 25.9% gave a positive history of animal contact. CONCLUSION: Patients with brucellosis presented with a wide range of clinical features, the most predominant of which was fever. The majority of patients were residents of or had recently visited Salalah and had consumed raw dairy products. These findings highlight the need for healthcare practitioners to maintain a high index of suspicion for this diagnosis. Moreover, further regulatory measures are necessary to oversee the sale of raw/unpasteurised dairy products.

Analysis of environmental dust in goat and sheep farms to assess Coxiella burnetii infection in a Q fever endemic area: Geographical distribution, relationship with human cases and genotypes.

Real-time PCR analysis of environmental samples (dust and aerosols) is an easy tool to investigate the presence of Coxiella burnetii in the farm environment. The aim of this study was to assess the distribution of C. burnetii DNA in dust collected inside animal premises from 272 small ruminant farms in Bizkaia (northern Spain), a region with recent reports of human Q fever cases and outbreaks. Within each farm, 5 samples of dust were collected from difference surfaces, and data on animal census, management procedures, characteristics of the premises and geographic location were collected. Real-time PCR analysis of the dust samples detected presence of C. burnetii DNA in 98 farms (36.0%), flock-prevalence being higher in sheep (38.9%) or mixed ovine-caprine production systems (36.8%), compared to goats (25.0%). Larger bacterial burdens were observed in mixed farms, compared to sheep (p < .05). Single nucleotide polymorphism (SNP) analysis identified 5 different genotypes, with SNP8 being the predominant genotype (73%), followed by SNP6 (11%), SNP2 (9%), SNP4 (5%) and SNP1 (2%). Proportion of farms where C. burnetii DNA was detected differed among the different agricultural counties, and a higher proportion of C. burnetii DNA positive farms was associated with the occurrence of recent human Q fever outbreaks at several geographical locations. Dust sampling in domestic ruminant farms coupled with real-time PCR to screen for the presence of C. burnetii and estimate bacterial load can be a useful tool to identify herds and regions with high prevalence, define priority actions and monitor the effect of control measures. If combined with molecular genotyping and spatial distribution maps, it can help to identify farm contamination sources and trace the origin of human outbreaks.

Seropositivity to canine tick-borne pathogens in a population of sick dogs in Italy.

BACKGROUND: Canine vector-borne diseases (CVBDs) associated to ticks are among the most important health issues affecting dogs. In Italy, Ehrlichia canis, Anaplasma spp., Rickettsia conorii and Borrelia burgdorferi (s.l.) have been studied in both healthy canine populations and those clinically ill with suspected CVBDs. However, little information is currently available on the overall prevalence and distribution of these pathogens in the country. The aim of this study was to assess the prevalence and distribution of tick-borne pathogens (TBPs) in clinically suspect dogs from three Italian macro areas during a 15-year period (2006-2020). METHODS: A large dataset (n = 21,992) of serological test results for selected TBPs in three macro areas in Italy was analysed using a Chi-square test to evaluate the associations between the categorical factors (i.e. macro area, region, year, sex and age) and a standard logistic regression model (significance set at P = 0.05). Serological data were presented as annual and cumulative prevalence, and distribution maps of cumulative positive cases for TBPs were generated. RESULTS: Of the tested serum samples, 86.9% originated from northern (43.9%) and central (43%) Italy. The majority of the tests was requested for the diagnosis of E. canis (47%; n = 10,334), followed by Rickettsia spp. (35.1%; n = 7725), B. burgdorferi (s.l.) (11.6%; n = 2560) and Anaplasma spp. (6.2%; n = 1373). The highest serological exposure was recorded for B. burgdorferi (s.l.) (83.5%), followed by Rickettsia spp. (64.9%), Anaplasma spp. (39.8%) and E. canis (28.7%). The highest number of cumulative cases of Borrelia burgdorferi (s.l.) was recorded in samples from Tuscany, central Italy. Rickettsia spp. was more prevalent in the south and on the islands, particularly in dogs on Sicily older than 6 years, whereas Anaplasma spp. was more prevalent in the north and E. canis more prevalent in the south and on the islands. CONCLUSIONS: The results of this study highlight the high seroprevalence and wide distribution of the four TBPs in dogs with clinically suspected CVBDs from the studied regions of Italy. The very high seroprevalence of B. burgdorferi (s.l.) exemplifies a limitation of this study, given the use of clinically suspect dogs and the possibility of cross-reactions when using serological tests. The present research provides updated and illustrative information on the seroprevalence and distribution of four key TBPs, and advocates for integrative control strategies for their prevention.

The epidemiology of bacterial zoonoses in pastoral and dairy cattle in Cameroon, Central Africa.

Previous work identified that bacterial zoonoses (Brucella species, Coxiella burnetii and Leptospira hardjo) were present in Cameroonian pastoral cattle. To assess the characteristics of this zoonotic risk, we analyse seroprevalence of each pathogen and the associated management, herd and environmental factors in Cameroonian pastoral and dairy cattle. Cross-sectional samples included pastoralist herds in the Northwest Region (NWR n = 750) and Vina Division (VD n = 748) and small holder dairy herds in the NWR (n = 60). Exposure to Brucella spp., C. burnetii and L. hardjo were screened for using commercial ELISAs and population adjusted estimates made. In addition, individual, herd and ecological metadata were collected and used to identify risk factors associated with animal-level seropositivity. In the pastoral cattle, seroprevalence to Brucella spp. was relatively low but was higher in the NWR (4.2%, CI: 2.5%-7.0%) than the VD (1.1%: CI 0.5%-2.4%), while L. hardjo seroprevalence was much higher though similar in the NWR (30.7%, CI 26.3%-35.5%) and VD (35.9%, CI 31.3%-40.7%). No differences were noted in C. burnetii seroprevalence between the two study sites (NWR: 14.6%, CI 11.8%-18.0%. VD: 12.4%, 9.6%-15.9%). Compared to pastoral, dairy cattle had lower seroprevalences for L. hardjo (1.7%, CI: 0.0%-4.9%), C. burnetii (0.0%, CI 0.0%-6.0%) but similar for Brucella spp. (5.0%, CI 0.0%-10.6%). Increased odds of Brucella spp. seropositivity were associated with owning sheep or rearing sheep and fencing cattle in at night. Adult cattle had increased odds of being seropositive for both C. burnetii and L. hardjo. Additionally, exposure to C. burnetii was associated with local ecological conditions and L. hardjo was negatively associated with cattle undertaking transhumance. This work highlights that exposure to these 3 important production diseases and occupational zoonoses are widespread in Cameroonian cattle. Further work is required to understand transmission dynamics between humans and livestock to inform implementation of effective control measures.

Ecological niche adaptation of Salmonella Typhimurium U288 is associated with altered pathogenicity and reduced zoonotic potential.

The emergence of new bacterial pathogens is a continuing challenge for agriculture and food safety. Salmonella Typhimurium is a major cause of foodborne illness worldwide, with pigs a major zoonotic reservoir. Two phylogenetically distinct variants, U288 and ST34, emerged in UK pigs around the same time but present different risk to food safety. Here we show using genomic epidemiology that ST34 accounts for over half of all S. Typhimurium infections in people while U288 less than 2%. That the U288 clade evolved in the recent past by acquiring AMR genes, indels in the virulence plasmid pU288-1, and accumulation of loss-of-function polymorphisms in coding sequences. U288 replicates more slowly and is more sensitive to desiccation than ST34 isolates and exhibited distinct pathogenicity in the murine model of colitis and in pigs. U288 infection was more disseminated in the lymph nodes while ST34 were recovered in greater numbers in the intestinal contents. These data are consistent with the evolution of S. Typhimurium U288 adaptation to pigs that may determine their reduced zoonotic potential.

Risk factors and true prevalence of bovine tuberculosis in Bangladesh.

Bovine tuberculosis (bTb) is endemic in Bangladesh but the true prevalence has not yet been reported. Our objectives for this study were to determine the true prevalence and identify risk factors for bTb at the animal- and herd-level in Bangladesh. A total of 510 cows were randomly selected during January 2018 to December 2018. Caudal fold (CFT) and comparative cervical tuberculin tests (CCT) were serially interpreted. Animal- and herd-level risk factor data were collected using a pre-tested questionnaire. The hierarchical true prevalence of bTb was estimated within a Bayesian framework. The herd- and animal-level risk factors were identified using mixed effects logistic regression. The apparent prevalence of bTb was 20.6% [95% Confidence Interval (CI): 17.3; 24.3] based on CFT. The animal-level true prevalence of bTb was 21.9 (13.0; 32.4). The herd-level true prevalence in different regions varied from 41.9% to 88.8%. The region-level true prevalence was 49.9 (13.8; 91.2). There is a 100% certainty that herds from Bhaluka and Mymensingh Sadar upazilas are not free from bTb. The odds of bTb were 3.9 times (1.2; 12.6) higher in herds having more than four cows than those with ≤ 4 cows. On the other hand, the risk of bTb was 3.3 times higher (1.0; 10.5) in non-grazing cows than grazing cows. Crossbred cows were 2.9 times (1.5; 5.9) more likely to be infected with bTb than indigenous cows. The risk of bTb in animals with cough was 2.3 times (1.2; 4.3) higher than those without cough. Crossbred, non-grazing cows with cough should be targeted for bTb surveillance. Herds of the Mymensingh, Sadar and Bhaluka regions should be emphasized for bTb control programs. Estimation of Bayesian hierarchical true prevalence facilitates identification of areas with higher prevalence and can be used to indicate regions that where true prevalence exceeds a pre-specified critical threshold.

Brucellosis screening and follow-up of seropositive asymptomatic subjects among household members of shepherds in China.

To measure the seroprevalence of high-exposure populations in brucellosis endemic areas and report the outcome and duration of seropositive asymptomatic subjects, we screened 595 family members of shepherds in Jilin Province, China and then followed up 15 seropositive asymptomatic subjects for 18 months. We found that the seropositive rate of 15.5%. Nearly half of seropositive asymptomatic subjects (7/15) developed into brucellosis in the short term; others were still seropositive asymptomatic or had decreased SAT titer in a longer time.