A multinational survey of companion animal veterinary clinicians: How can antimicrobial stewardship guidelines be optimised for the target stakeholder?

Antimicrobial stewardship initiatives are widely regarded as a cornerstone for ameliorating the global health impact of antimicrobial resistance. Within companion animal health, such efforts have largely focused on development and dissemination of antimicrobial stewardship guidelines (ASGs). However, there have been few attempts to understand veterinarian attitudes towards and knowledge of ASGs or to determine how awareness regarding ASGs might best be increased. An online survey regarding ASGs was formulated for veterinarians who treat companion animals. The survey was distributed across 46 European and associated countries between 12 January and 30 June, 2022. In total, 2271 surveys were completed, with 64.9% of respondents (n = 1474) reporting awareness and usage of at least one ASG. Respondents from countries with greater awareness of ASGs tended to report more appropriate use of antimicrobials (Spearman's rank coefficient = 0.6084, P ≤ 0.001), with respondents from countries with country-specific ASGs tending to score highest across both awareness and appropriate use domains. Respondents prioritised guidance around antimicrobial choice (82.0%, n = 1863), duration of treatment (66.0%, n = 1499), and dosage (51.9%, n = 1179) for inclusion in future ASGs, with 78.0% (n = 1776) of respondents preferring ASGs to be integrated into their patient management system. Awareness of ASGs and their use in companion animal veterinary practice appears to be greater than previously reported, with respondents tending to report antimicrobial prescription decision making broadly in line with current clinical recommendations. However, further initiatives aimed at maximising accessibility to ASGs both within countries and individual veterinary practices are recommended.

Investigation on the incidence of adverse reactions, viraemia and haematological changes following field immunization of cattle using a live attenuated vaccine against lumpy skin disease.

The present study was performed to investigate the clinical impact and certain virological and haematological parameters following immunization of cattle against lumpy skin disease (LSD). The study was conducted in a dairy cattle farm (215 animals), immunized with a Neethling strain-based live vaccine. Twenty-seven animals (14 lactating cows, four dry cows and nine calves) were randomly selected for repetitive blood and saliva samplings. An EvaGreen-based real-time PCR was designed to differentiate vaccine from field LSDVs. Vaccinated animals underwent examination for adverse reactions. Nodule samples were collected from two representative cases for histopathological testing and virus identification. Milk yield was calculated based on bulk-tank measurements of all lactating cows (79). Viral DNA was detected between days 6-15 post-vaccination (p.v.) at 63% of the sampled animals (17/27). Saliva and bulk-tank milk samples were LSDV-negative. Pronounced swelling was observed at injection sites of 12% of the immunized animals (26/215), starting at day 6 p.v., and was resolved after 2-4 days. Small-sized (<0.5 cm) cutaneous lumps were developed between days 8-18 p.v. at 9% of the vaccinated animals (19/215). These were observed in adult cows and not in calves/heifers. Resolution was observable 10 days post-development. The vaccine virus was also identified in nodules and injection-site aspirates. Haematological changes (e.g., lower leucocyte counts) were observed in cows and not in calves. Daily milk production was being reduced during the first 12 days p.v. LSD immunization of cows resulted in nodules and low viraemia levels. The fact that nodules and haematological changes were not observed in calves, along with the low viraemia, supports the reduced virulence of the Neethling vaccine strain. The characteristic nodules in vaccinated animals could allow clinical differentiation from those observed in LSD. The developed real-time PCR efficiently differentiates infected from vaccinated cattle, and should be further validated as a tool in LSD surveillance.

Emergence of Equine West Nile Encephalitis in Central Macedonia, Greece, 2010.

During the summer of 2010, an outbreak of West Nile virus (WNV) infections attributed to a lineage 2 WNV strain was reported among humans and horses in Central Macedonia, Northern Greece. Here, the clinical and laboratory investigation of horses that showed severe neurological signs due to WNV infection is being described. Specifically, between August and September 2010, 17 horses with neurological signs were detected. WNV infection was confirmed in all 17 clinical cases by applying laboratory testing. The duration of WNV-specific IgM antibodies in sera obtained from seven of the clinically affected horses was relatively short (10-60 days; mean 44 days). In the regional unit of Thessaloniki, (i) seroprevalence of WNV and fatality rate in horses were high (33% and 30%, respectively), and (ii) the ratio of neurological manifestations-to-infections for this virus strain was high (19%). These observations indicate that the strain responsible for the massive human epidemic of 2010 in Greece was also highly pathogenic for horses. This is the first time that WNV infection has been documented in horses with clinical manifestations in Greece. WNV infection should be included in the differential diagnosis of horses with encephalitis in Greece.

Surveillance and Early Warning of West Nile Virus Lineage 2 Using Backyard Chickens and Correlation to Human Neuroinvasive Cases.

In 2010, a West Nile virus (WNV) epidemic was reported in Central Macedonia, Northern Greece, with 197 neuroinvasive disease (WNND) cases in humans. The following 3 years, WNV spreads to new areas of Greece and human cases reoccurred during the transmission periods. After the initial outbreak, a WNV surveillance system using juvenile backyard chickens was established in Central Macedonia (after the 2011 outbreak) and Eastern Macedonia-Thrace (after the 2012 outbreak). Sera were screened for the presence of antibodies against WNV using cELISA and serum neutralization test, to monitor the spread of WNV and to assess the correlation between the WNV point seroprevalence in chickens and the incidence rates of human WNND cases in the aforementioned areas. WNV seroprevalence in chickens was 10.4% (95% CI: 7-15) in Central Macedonia (2011) and 18.1% (95% CI: 14-23) in Eastern Macedonia-Thrace (2012). Seroprevalence in chickens and incidence rates of human WNND cases in Eastern Macedonia-Thrace were strongly positively correlated (ρ = 0.98, P = 0.005) at the regional unit level, with the incidence of WNND in humans increasing with increasing WNV point seroprevalence in chickens. In Central Macedonia, the correlation was weaker (ρ = 0.68, P = 0.20), apparently due to small number of reported human WNND cases. Another study was also conducted using juvenile backyard chickens in Central Macedonia, aiming to detect early WNV enzootic circulation, before the onset of human cases during 2011 and 2013. The first seroconverted chickens were detected about 1.5 months before the laboratory diagnosis of any human WNND cases in Central Macedonia, for both years. WNV surveillance, using juvenile backyard chickens, was reliable for the identification of areas with WNV enzootic and silent transmission, and for early warning. Timely diffusion of information to public health authorities facilitated the successful implementation of preparedness plans to protect public health.