Characterization of Erysipelothrix rhusiopathiae Isolates from Diseased Pigs in 15 Chinese Provinces from 2012 to 2018

Erysipelothrix rhusiopathiae can cause erysipelas in animals and erysipeloid in humans. Since its recurrence in 2012, swine erysipelas has caused serious losses within the pig industry in China. The aim of this study was to perform multilocus sequence typing and understand the virulence and antimicrobial susceptibility of E. rhusiopathiae isolates in China. Multilocus sequence typing (MLST) of a total of 120 strains was performed, and as a result, three different sequence types were identified, of which ST48 was the main one. Five isolates of each MLST type were randomly selected to be used to challenge mice. ST48 was associated with a higher virulence. Antimicrobial susceptibility was tested using a microdilution technique and, to analyze the resistance mechanism, six strains were selected for genome sequencing. A comparison of the six genomes indicated the presence of a suspected macrolide resistance gene, namely, Erm(A)-like, in erythromycin-resistant strains, which increased the minimum inhibitory concentration (MIC) of erythromycin against E. coli C600 at least four-fold. In addition, three mutations (gyrA86T-I, gyrA90D-N, and parC81S-I) were observed in the quinolone resistance-determining regions (QRDRs) of gyrA and parC in quinolone-resistant strains. After the gyrA gene with the 86T-I mutation or the parC gene with the 81S-I mutation was transfected into E. coli C600, the MIC of enrofloxacin against this strain increased at least two-fold. Our findings provide a theoretical basis for developing antibacterial drugs and may contribute to the clinical prevention and control of E. rhusiopathiae.

Osteoarticular infections caused by Erysipelothrix rhusiopathiae: a case report and literature review

We present a case of Erysipelothrix rhusiopathiae spondylodiscitis in an otherwise healthy man, occurring one year after exposure. The patient was cured after 6-weeks treatment with amoxicillin followed by ciprofloxacin without surgery. E. rhusiopathiae can cause severe osteoarticular infections with a delayed presentation following the exposure to the pathogen.

Erysipelothrix rhusiopathiae infection by geese to human transmission

Erysipelothrix rhusiopathiae transmission to human is often occupation-related, but in most cases, a detailed case history is missing. This case report is based on an interdisciplinary approach and includes a thorough medical record. A 58-year-old laboratory technician working on geese necropsy cut open her glove at a rib fragment of a goose and subsequently noticed a slowly progressive, reddish skin alteration in the particular region of the hand. Bacteriological investigations on the geese revealed septicaemia due to E. rhusiopathiae and therefore substantiated the diagnosis of the patient. The infectious agent could not be cultured from the patient; however, antibiotic susceptibility testing was performed using the goose isolate. An entire follow-up until full recovery of the patient was conducted. Zoonotic infections possibly have a significant impact on certain occupations. This case report analyses a rare but important zoonotic infection to create awareness of this in physicians caring for human patients.

Comparative Analysis of the Productivity and Immunogenicity of an Attenuated Classical Swine Fever Vaccine (LOM) and an Attenuated Live Marker Classical Swine Fever Vaccine (Flc-LOM-BErns) from Laboratory to Pig Farm

Herein, we compared the productivity of pigs inoculated with one of two classical swine fever (CSF) vaccines (low virulent of Miyagi (LOM) or Flc-LOM-BErns) plus the swine erysipelothrix rhusiopathiae (SE) vaccine. The feed intake and weight increase of the pigs inoculated with Flc-LOM-BErns + SE were normal. However, the feed intake of the pigs inoculated with LOM + SE dropped sharply from four days post-vaccination (dpv). In addition, the slaughter date was an average of eight days later than that of the pigs inoculated with Flc-LOM-BErns + SE. All pigs inoculated with the Flc-LOM-BErns + SE vaccine were completely differentiated at 14 days against CSF Erns antibody and at approximately 45 days against the bovine viral diarrhea virus (BVDV) Erns antibody; the titers were maintained until slaughter. Leucopenia occurred temporarily in the LOM + SE group, but not in the Flc-LOM-BErns + SE group. Expression of tumor necrosis factor (TNF)-α and IFN-γ was significantly (p < 0.05) higher in the LOM + SE group than in the mock (no vaccine) group. When conducting the same experiment on a breeding farm, the results were similar to those of the laboratory experiments. In conclusion, the biggest advantage of replacing the CSF LOM vaccine with the Flc-LOM-BErns vaccine is improved productivity.

Swine Erysipelas; It’s Epidemiology, Diagnosis, Treatment and Control and Preventive Measures, Comprehensive Review

Erysipelas is an infectious disease seen mainly in growing pigs and characterized clinically by fever, arthritis, skin lesions and sudden death. The disease may be acute, subacute, or chronic. Swine erysipelas is a disease caused by a specific micro organ Erysipelothrix rhusiopathiae whic h is a zoonotic ubiquitous gram-positive bacterium that causes erysipelas in swine, mammals, birds and erysipeloid in humans. People in contact with animals, animal products or animal wastes are at greatest risk. The acute form of swine erysipelas may have been confused for other diseases in pigs which are characterized by acute symptoms such as sudden death (for example, African swine fever). It can be diagnosed by its clinical signs, necropsy findings, bacteriology, antimicrobial response, molecular and serological examinations. It is recommended to increase awareness of the disease among animal and human practitioners as treatment is easy and available and vaccination is possible. However, the disease is still unknown to local veterinarians, clinical doctors, meat inspectors, butchers and laboratory personnel. Proper hygiene, regular pork inspection, use of protective wear among people working/ in contact with animals should be promoted. The disease causes high economic loss in pig rearing areas and influences the public health being a severe zoonotic disease. So the objective of this review is to create a better understanding of the disease for proper control and prevention of the disease

Purchasing policy, quarantine and acclimation practices of breeding gilts in Belgian pig farms

Background The breeding population is very important in pig herds, for productivity, health and profitability. Replacement of breeding animals can be accomplished by own rearing of breeding gilts or by purchasing them. Purchasing breeding gilts is a hazardous event in terms of biosecurity and introduction of pathogens into a farm. However, in literature, little is known about gilt introduction in a herd. The present study investigated the introduction procedures of purchased breeding gilts in Belgian pig herds, and the compliance of these herds to the optimal introduction procedures. A questionnaire consisting of twenty questions related to farm characteristics (n = 2), purchasing policy (n = 6), quarantine period (n = 5), and acclimation practices (n = 7) was designed, and 68 farms completed the questionnaire during an on-farm interview. Results The median (min. – max.) number of sows on the farms was 300 (85–2500). Fifty-seven per cent of the farms purchased breeding gilts, and there was a lot of variation in the frequency of purchase and the age at which gilts are purchased. On 95 % of those farms, a quarantine unit was used, and on most of these farms the quarantine was located on the farm itself (internal quarantine). The median (min. – max.) duration of the quarantine period was 42 (14–140) days. The most common acclimation practice was vaccination against Porcine parvovirus (96 %) and Erysipelothrix rhusiopathiae (94 %), although in some farms exposure of gilts to farm-specific micro-organisms was done by providing faeces from suckling piglets (18 %) and bringing gilts in contact with sows that will be culled (16 %). Only 10 % of the farms complied with the optimal introduction procedures, i.e. purchasing policy, quarantine building and quarantine management. Conclusions This study showed that in many farms, practices related to purchasing, quarantine and acclimation could be improved to maintain optimal biosecurity.

Quantification of IgY to Erysipelothrix rhusiopathiae in serum from Swedish laying hens

Background Erysipelas, caused by Erysipelothrix rhusiopathiae (ER), is an important emerging disease in free-range and organic egg-production. The aim of the present study was to assess if quantification of ER specific IgY titers may aid the understanding of erysipelas in commercial laying hens. The methodology was validated with sequentially collected sera from experimentally ER infected SPF-chickens and subsequently applied on sera from Swedish commercial laying hens collected during and after outbreaks of erysipelas or collected at slaughter from healthy hens housed in furnished cages, barn production or in organic production (with outdoor access). Results In experimentally infected SPF-chickens, titers to ER were significantly increased approximately one week after infection while IgY to ER in uninfected age-matched controls remained low. Also chickens infected with low doses of ER, not displaying clinical signs of disease and with low recovery of ER in blood samples showed high titers of IgY to ER. For laying hens during and after erysipelas outbreaks the majority of samples were considered positive for antibodies to ER with a large variation in levels of IgY titers to ER between individuals. For healthy laying hens at slaughter all samples were deemed positive for antibodies to ER. An influence of flock on levels of IgY titers to ER was observed for both healthy hens and hens during erysipelas outbreaks. For healthy laying hens at slaughter no influence of the housing systems included in the study, history of erysipelas outbreaks at the farm or vaccination on levels of IgY titers to ER was noticed. Conclusions Taken together, these results show that high numbers of commercial laying hens showed high IgY titers to ER, comparable to those elicited by experimental ER infection, indicating that ER or bacteria that raises antibodies that cross-react with ER are common in this environment.