Objective—To evaluate effectiveness of 4% peroxymonosulfate
disinfectant applied as a mist to surfaces
in a large animal hospital as measured by recovery of
Staphylococcus aureus and Salmonella enterica
Sample Population—Polyester transparencies inoculated
Procedure—Polyester transparencies were inoculated
with S aureus or S Typhimurium and placed in various
locations in the hospital. After mist application of the
peroxygen disinfectant, viable bacterial numbers were
quantified and compared with growth from control
transparencies to assess reduction in bacterial count.
Results—When applied as a mist directed at environmental
surfaces contaminated with a geometric
mean of 4.03 × 107 CFUs of S aureus (95% confidence
interval [CI], 3.95 × 107 to 4.11 × 107) or 6.17 ×
106 CFUs of S Typhimurium (95% CI, 5.55 × 106 to
6.86 × 106), 4% peroxymonosulfate reduced the geometric
mean number of viable S aureus by 3.04 × 107
CFUs (95% CI, 8.6 × 105 to 1.7 × 106) and S
Typhimurium by 3.97 × 106 CFUs (95% CI, 8.6 × 105 to
3.5 × 106).
Conclusions and Clinical Relevance—Environmental
disinfection with directed mist application of a 4% peroxymonosulfate
solution was successful in reducing
counts of bacterial CFUs by > 99.9999%. Directed
mist application with this peroxygen disinfectant as
evaluated in this study appeared to be an effective and
efficient means of environmental disinfection in a large
animal veterinary hospital and would be less disruptive
than more traditional approaches to intensive environmental
cleaning and disinfection. (J Am Vet Med
Objective—To compare the efficacy of a peroxygenbased disinfectant used in footbaths with the efficacy of the same disinfectant used in footmats for reducing bacterial contamination of footwear in a large animal hospital.
Sample Population—Bacteria recovered from the soles of rubber boots after experimental microbial contamination and exposure to disinfectant solutions or water (water-treated control boots) or no treatment (untreated control boots).
Procedures—Investigators contaminated boots by walking through soiled animal bedding. Swab samples were collected from the sole of 1 untreated boot (right or left); the other boot was treated as investigators stepped through a disinfectant-filled footbath, a disinfectant-filled footmat, or water-filled footmat. Samples were collected 10 minutes after each treatment. Differences in numbers of bacteria recovered from treated and untreated boots were analyzed.
Results—Mean bacterial counts from peroxygentreated boots were 1.3 to 1.4 log10 lower (95.4% to 99.8%) than the counts from untreated boots. Results were similar for footmat- and footbath-treated boots. In contrast, there were no statistically detectable differences in mean bacterial counts in samples collected from water-treated or untreated boots.
Conclusions and Clinical Relevance—Results suggest that footmats and footbaths containing peroxygenbased disinfectant are effective in reducing bacterial contamination on the soles of boots when used in conditions representative of large animal hospitals. Similar results were achieved with use of either footmats or footbaths. The use of footbaths and footmats containing effective disinfectants may help decrease the risk for spread of nosocomial infection but should not be expected to sterilize footwear.
Objective—To evaluate the effects of footwear hygiene protocols on bacterial contamination of floor surfaces in an equine hospital.
Procedures—Footwear hygiene protocols evaluated included use of rubber overboots with footbaths and footmats containing a quaternary ammonium disinfectant, rubber overboots with footbaths and footmats containing a peroxygen disinfectant, and no restrictions on footwear type but mandatory use of footbaths and footmats containing a peroxygen disinfectant. Nonspecific aerobic bacterial counts were determined via 2 procedures for sample collection and bacterial enumeration (contact plates vs swabbing combined with use of spread plates), and the effects of each footwear hygiene protocol were compared.
Results—There were no consistent findings suggesting that any of the protocols were associated with differences in numbers of bacteria recovered from floor surfaces. Although there were detectable differences in numbers of bacteria recovered in association with different footwear hygiene protocols, differences in least square mean bacterial counts did not appear to be clinically relevant (ie, were < 1 log10).
Conclusions and Clinical Relevance—Although cleaning and disinfection of footwear are important aids in reducing the risk of nosocomial transmission of infectious agents in veterinary hospitals, the numbers of aerobic bacteria recovered from floor surfaces were not affected by use of rubber overboots or the types of disinfectant used in this study. Further study is warranted to evaluate the usefulness of footwear hygiene practices relative to their efficacy for reducing transmission of specific pathogens or decreasing nosocomial disease risk.
Objective—To monitor ovine herpesvirus type 2
(OvHV-2) infection status and the association
between OvHV-2 infection and development of clinical
signs of malignant catarrhal fever (MCF) in cattle.
Animals—30 mature adult cows and 18 cattle submitted
Procedure—Blood and milk samples were collected at
monthly intervals from 30 adult cows for 20 consecutive
months. Nasal and ocular swab specimens were also
collected during months 9 through 20. Polymerase chain
reaction (PCR) assay for detection of OvHV-2 was performed
on blood, milk, nasal swab, and ocular swab
specimens. Competitive inhibition ELISA (CI-ELISA) for
detection of antibodies against MCF viruses was performed
on serum samples obtained prior to study initiation
and monthly during the last 12 months. Tissues
obtained from herdmates without clinical signs of MCF
that were submitted for necropsy were analyzed for
OvHV-2 DNA via PCR assay for possible sites of latency.
Results—Initially, 8 of 30 cows had positive CI-ELISA
results. Seroconversion was detected in 4 cows. Ovine
herpesvirus type 2 DNA was intermittently detected in
blood, milk, nasal secretions, or ocular secretions from
17 of 30 cows. Twenty-one cows had positive CI-ELISA
or PCR assay results. No cattle in the study developed
clinical signs of MCF. Results of PCR assays performed
on tissue samples from 2 of 18 animals submitted for
necropsy were positive for OvHV-2.
Conclusions and Clinical Relevance—OvHV-2 infection
can occur in cattle without concurrent development
of clinical MCF. Ovine herpesvirus type 2 DNA
was detected intermittently, suggesting fluctuating
viral DNA loads or reinfection in subclinical cattle. A
definitive site of latency was not identified from tissues
obtained during necropsy. (J Am Vet Med Assoc