Experimental Infection of Mexican Free-Tailed Bats (Tadarida brasiliensis) with SARS-CoV-2

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus is thought to have originated in wild bats from Asia, and as the resulting pandemic continues into its third year, concerns have been raised that the virus will expand its host range and infect North American wildlife species, including bats. Mexican free-tailed bats (Tadarida brasiliensis) live in large colonies in the southern United States, often in urban areas and, as such, could be exposed to the virus from infected humans. We experimentally challenged wild T. brasiliensis with SARS-CoV-2 to determine the susceptibility, reservoir potential, and population impacts of infection in this species. Of 10 bats oronasally inoculated with SARS-CoV-2, 5 became infected and orally excreted moderate amounts of virus for up to 18 days postinoculation. These five subjects all seroconverted and cleared the virus before the end of the study with no obvious clinical signs of disease. We additionally found no evidence of viral transmission to uninoculated subjects. These results indicate that while T. brasiliensis are susceptible to SARS-CoV-2 infection, infection of wild populations of T. brasiliensis would not likely cause mortality. However, the transmission of SARS-CoV-2 from T. brasiliensis to or from humans, or to other animal species, is a possibility requiring further investigation to better define. IMPORTANCE As the COVID-19 pandemic has continued for 3+ years, there has been increasing concern that the SARS-CoV-2 virus will enter wildlife populations and potentially create new reservoirs where the virus could adapt to a new host and create variants. This is particularly possible with species that reside in man-made structures, in proximity to infected human populations. Mexican free-tailed bats (Tadarida brasiliensis) live in large colonies, often in urban settings and, thus, can be exposed by infected humans and potentially transmit the virus to new hosts. We experimentally challenged T. brasiliensis with SARS-CoV-2 and revealed that they are susceptible to the virus and excrete moderate amounts for up to 18 days postinoculation. This is important information for wildlife biologists, wildlife rehabilitation workers, and the general public that may contact these animals.

Experimental infection of Mexican free-tailed bats ( Tadarida brasiliensis) with SARS-CoV-2

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus originated in wild bats from Asia, and as the resulting pandemic continues into its third year, concerns have been raised that the virus will expand its host range and infect North American wildlife species, including bats. Mexican free-tailed bats ( Tadarida brasiliensis : TABR) live in large colonies in the southern United States, often in urban areas, and as such, could be exposed to the virus from infected humans. We experimentally challenged wild TABR with SARS-CoV-2 to determine the susceptibility, reservoir potential, and population impacts of infection in this species. Of nine bats oronasally inoculated with SARS-CoV-2, five became infected and orally excreted moderate amounts of virus for up to 18 days post inoculation. These five subjects all seroconverted and cleared the virus before the end of the study with no obvious clinical signs of disease. We additionally found no evidence of viral transmission to uninoculated subjects. These results indicate that while TABR are susceptible to SARS-CoV-2 infection, infection of wild populations of TABR would not likely cause mortality. However, the transmission of SARS-CoV-2 from TABR to or from humans, or to other animal species, is a distinct possibility requiring further investigation to better define.

Prospective evaluation of the safety of compounded bulk material L-asparaginase in dogs with lymphoma

Use of compounded L-asparaginase became routine in veterinary oncology when manufacturing of Elspar^® was discontinued in 2012. The objective of this study was to evaluate the safety of compounded L-asparaginase (CLASP, KRS Global Biotechnology, Boca Raton, FL, USA) in comparison with Elspar^® (Lundbeck LLC, Deerfield, IL, USA). In addition, we documented the response to CLASP in combination with a corticosteroid in this population of dogs with lymphoma. Dogs were prospectively treated with 10 000 IU/m² CLASP or Elspar^® subcutaneously. Corticosteroids were administered concurrently. Adverse events (AE) were assessed according to the Veterinary Cooperative Oncology Group Common Terminology Criteria for Adverse Events v1.1 (VCOG-CTCAE). Response was recorded. Seventy-three dogs received 75 treatments (CLASP, n = 47; Elspar^® , n = 28). No AE were attributed to CLASP. Grade I and II AE probably or possibly related to treatment were observed following two Elspar^® treatments. The overall response rate to the combination of CLASP and a corticosteroid was 80% (24% CR and 56% PR). In combination with a steroid, the compounded L-asparaginase evaluated in this study is safe and demonstrates activity against canine lymphoma. In the face of the discontinuation of Elspar^® , veterinarians should seek compounded LASP products that have been tested for activity, purity, and sterility.

Interpretation of Post-operative Distal Humerus Radiographs After Internal Fixation: Prediction of Later Loss of Fixation

PURPOSE

Stable fixation of distal humerus fracture fragments is necessary for adequate healing and maintenance of reduction. The purpose of this study was to measure the reliability and accuracy of interpretation of postoperative radiographs to predict which implants will loosen or break after operative treatment of bicolumnar distal humerus fractures. We also addressed agreement among surgeons regarding which fracture fixation will loosen or break and the influence of years in independent practice, location of practice, and so forth.

METHODS

A total of 232 orthopedic residents and surgeons from around the world evaluated 24 anteroposterior and lateral radiographs of distal humerus fractures on a Web-based platform to predict which implants would loosen or break. Agreement among observers was measured using the multi-rater kappa measure.

RESULTS

The sensitivity of prediction of failure of fixation of distal humerus fracture on radiographs was 63%, specificity was 53%, positive predictive value was 36%, the negative predictive value was 78%, and accuracy was 56%. There was fair interobserver agreement (κ = 0.27) regarding predictions of failure of fixation of distal humerus fracture on radiographs. Interobserver variability did not change when assessed for the various subgroups.

CONCLUSIONS

When experienced and skilled surgeons perform fixation of type C distal humerus fracture, the immediate postoperative radiograph is not predictive of fixation failure. Reoperation based on the probability of failure might not be advisable.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.

Treatment time, ease of use and cost associated with use of Equashield™, PhaSeal® , or no closed system transfer device for administration of cancer chemotherapy to a dog model

This prospective experimental simulation study evaluated the efficiency, ease of use (EOU) and cost of administering chemotherapy with two closed system transfer devices (CSTD, Equashield™ and PhaSeal^® ) and no CSTD. Forty-six veterinary technicians (VT) working in oncology specialty practices were timed during chemotherapy administration simulated with water and a model canine limb 10 times with each system and with no CSTD. EOU and likelihood of recommending each system were rated by VT using visual analog scales. Costs were obtained from veterinary distributors. Administration was fastest with Equashield™ (P = 0.0003), but the difference was not enough to affect case flow. Equashield™ was easier to use than PhaSeal^® or no CSTD (P = 0.002), however VT recommended both CSTD more strongly than no CSTD (P < 0.0001). Equashield™ cost less than PhaSeal^® but was sold only in bulk quantities. CSTD did not decrease efficiency in administering chemotherapy and were readily accepted by VT.

Functional cystic thyroid adenoma in a cat

A 9-year-old cat with hyperthyroidism was referred for radioactive iodine treatment. The cat also had a ventral cervical mass that the owners reported had been present for several years and had increased in size during the past few weeks. On physical examination, the mass was found to have caused lateral displacement of the trachea, esophagus, jugular vein, and common carotid artery. The mass was aspirated and was determined to be cystic in nature. Concentrations of thyroid hormones in the cystic fluid were similar to serum concentrations, and nuclear scintigraphy revealed thyroactive tissue lining the cyst wall. Magnetic resonance imaging suggested that the cyst originated from the right lobe of the thyroid gland. The cat was treated with sodium iodide I 131 but died 4 days later, presumably as a result of aspiration of gastric or esophageal contents. A necropsy was not performed, but histologic examination of a biopsy specimen of the mass indicated that it was a cystic thyroid adenoma.

Serodiagnosis of human granulocytic ehrlichiosis by using novel combinations of immunoreactive recombinant proteins

A panel of seven recombinant antigens, derived from Ehrlichia phagocytophila (the agent of human granulocytic ehrlichiosis), was evaluated by class-specific enzyme-linked immunosorbent assays (ELISAs) for utility in the diagnosis of the infection. Fourteen genomic fragments, obtained by serologic expression screening, contained open reading frames (ORFs) encoding 16 immunodominant antigens. Eleven of these antigens were members of the major surface protein (MSP) multigene family. Alignment of their predicted protein sequences revealed a pattern of conserved sequences, which contained short direct repeats, flanking a variable region. In addition, two genomic clones contained two and three MSP ORFs, respectively, indicating that these genes are clustered in tandem copies. The implications for this pattern of both genomic and protein arrangements in antigenic variations of MSPs and in their utilities in a diagnostic assay are discussed. In addition to two MSP recombinant antigens (rHGE-1 and -3) and a fusion protein of these antigens (rErf-1), five further recombinants were evaluated by ELISA. Two of these antigens (rHGE-14 and -15) were novel, while a third (rHGE-2), with no known function, has been described. The final two recombinant antigens (rHGE-9 and -17) represent overlapping segments of the ankyrin gene (ank). The addition of rHGE-9 ELISA data resulted in the detection of 78% (21 of 27) of acute-phase sera. When serologic data for all recombinants are combined, 96.2% (26 of 27) of convalescent-phase patient serum samples and 85.2% (23 of 27) of acute-phase patient serum samples are detected, indicating the potential of these antigens for use in the development of a rapid serologic assay for the detection of E. phagocytophila infection.

Necrotizing fasciitis as complication of injection into greater trochanteric bursa

Necrotizing fasciitis is a limb- and life-threatening soft-tissue infection that frequently involves the extremities. This article describes the first case of necrotizing fasciitis developing from a single steroid injection of the greater trochanteric bursa. Despite early resuscitation and aggressive surgical management that included a hip disarticulation, the patient expired. Potential contributing factors are reviewed.

Quantitative detection of Borrelia burgdorferi with a microtiter-based competitive polymerase chain reaction assay

BACKGROUND

The current understanding of the inflammation associated with Lyme disease directly involves infection caused by Borrelia burgdorferi within specific target tissues, accompanied by a significant host immunologic component driving the inflammatory process. The measurement of spirochetal tissue burden may thus be useful for studying animal models of Lyme disease pathogenesis. Widely available methods based on the culture of spirochetes from tissues do not provide quantitative information.

METHODS

We developed and evaluated a quantitative-competitive polymerase chain reaction assay based on amplification of the B. burgdorferi flagellin gene. The assay makes use of a competitive internal standard and a commercially available enzyme-linked immunosorbent assay detection kit.

RESULTS AND CONCLUSION

The assay clearly discriminated between infected and uninfected mouse tissues, and an accurate quantitation range of 500 to 20,000 spirochetes per milligram of tissue was obtained. C3H mice were shown to harbor greater amounts of spirochetal genomic DNA than BALB/c mice. Normalization of samples by tissue weight and genomic DNA content both provided acceptable results. These data indicate this assay can be used to provide reliable and meaningful measurements of spirochetal infectious burden, which will be extremely useful for the study of Lyme disease pathogenesis in the murine model.

White-tailed deer as a potential reservoir of Ehrlichia spp

We determined the antibody prevalence to Ehrlichia spp., in white-tailed deer (Odocoileus virginianus) and the geographic distribution of seropositive animals in 84 counties in Alabama, Arkansas, Florida, Georgia, Illinois, Kentucky, Louisiana, Maryland, Massachusetts, Mississippi, Missouri, North Carolina, South Carolina, Tennessee, Texas, Virginia, and West Virginia (USA). Using an indirect fluorescent antibody test we detected antibodies (> or = 1:128) to this bacterium in 544 (43%) of 1269 deer. Presence of antibodies to Ehrlichia spp. was related to a southerly latitude, low elevation, and resulting milder climatic conditions. It appears that white-tailed deer were naturally infected with Ehrlichia spp.; the infection was widely distributed throughout the southeastern United States. Based on these data, we propose that white-tailed deer play a role in the natural history of Ehrlichia spp. infection in the United States.

[Inhalation anaesthesia in bronchoscopies on infants and small children (author's transl)]

Over the past 5 years 37 bronchoscopies were performed on children aged 7 months to 3 years for the removal of foreign bodies, the diagnosis of inflammations, and the cause of chronic stridor. Because of improved instrumentation, illumination with "cold light" and cooperation between endoscopist and anaesthesist there were no complications. Anaesthesia was achieved by a mixture of oxygen, nitrous oxide and fluothane without use of muscle relaxants. Each child was given Atropine and Solu-Decortin H and if indicated Calcium gluconate and Euphillin. These endoscopies, except in three children with gross inflammation, were carried out as out-patient procedures. Early endoscopy in the doubtful case is desirable, since later complications may make anaesthetic conditions hazardous.