Concurrent administration of an intranasal vaccine containing feline herpesvirus-1 (FHV-1) with a parenteral vaccine containing FHV-1 is superior to parenteral vaccination alone in an acute FHV-1 challenge model

The administration of intranasal (IN) or subcutaneous (SC) vaccines containing modified live feline herpesvirus 1 (FHV-1) offers some level of protection against FHV-1 challenge, but relative efficacy is <100%. In this study, clinical signs and viral shedding in kittens were compared among three groups: (1) kittens vaccinated concurrently with IN and SC vaccines containing FHV-1 (Group 1, n = 8); (2) kittens vaccinated with a SC FHV-1 vaccine alone (Group 2, n = 8), and (3) unvaccinated control kittens (Group 3, n = 8). All kittens were FHV-1 naïve at enrolment, and challenge with a virulent strain of FHV-1 was performed 1 week after vaccination. Daily clinical signs and pharyngeal FHV-1 shedding were recorded over a 21-day infection period. Overall, kittens in Group 1 had significantly less severe clinical illness than those in Group 2 (P < 0.05). Additionally, significantly less FHV-1 DNA was detected on pharyngeal swabs from kittens in Group 1 compared to those in Group 2 (P < 0.001). Concomitant administration of IN and SC FHV-1 vaccines was superior to administration of the SC FHV-1 vaccine alone in this challenge model of FHV-1 naïve kittens.

Prevalence of Bartonella species, hemoplasmas, and Rickettsia felis DNA in blood and fleas of cats in Bangkok, Thailand

Flea infestations are common in Thailand, but little is known about the flea-borne infections. Fifty flea pools and 153 blood samples were collected from client-owned cats between June and August 2009 from veterinary hospitals in Bangkok, Thailand. Total DNA was extracted from all samples, and then assessed by conventional PCR assays. The prevalence rates of Bartonella spp. in blood and flea samples were 17% and 32%, respectively, with DNA of Bartonella henselae and Bartonella clarridgeiae being amplified most commonly. Bartonella koehlerae DNA was amplified for the first time in Thailand. Hemoplasma DNA was amplified from 23% and 34% of blood samples and flea pools, respectively, with 'Candidatus Mycoplasma haemominutum' and Mycoplasma haemofelis being detected most frequently. All samples were negative for Rickettsia felis. Prevalence rate of B. henselae DNA was increased 6.9 times in cats with flea infestation. Cats administered flea control products were 4.2 times less likely to be Bartonella-infected.

Antibodies against Crandell Rees feline kidney (CRFK) cell line antigens, alpha-enolase, and annexin A2 in vaccinated and CRFK hyperinoculated cats

BACKGROUND

Cats inoculated with feline herpesvirus 1, calicivirus, and panleukopenia (FVRCP) vaccines grown on the Crandell Rees feline kidney (CRFK) cell line have been shown to develop anti-CRFK antibodies. The identities of common CRFK antigens are unknown.

HYPOTHESIS

Cats inoculated with CRFK lysates and FVRCP vaccines will develop autoantibodies measurable by Western blot immunoassay. Antigens associated with these antibodies can be isolated for further study.

ANIMALS

One CRFK hyperinoculated rabbit, 44 age-matched unvaccinated kittens purchased from a commercial vendor.

METHODS

Commonly recognized CRFK antigens were identified by comparison of Western blot immunoassays using sera from a hyperinoculated rabbit and kittens inoculated with CRFK lysate or 1 of 4 commercially available FVRCP vaccines. Antigens were purified from CRFK lysates and sequenced. Antigen recognition was confirmed by Western blot immunoassay and indirect ELISA for 2 proteins using sera from CRFK and FVRCP inoculated kittens.

RESULTS

CRFK antigens 47, 40, and 38 kD in size were identified. Protein isolation and sequencing identified 3 CRFK proteins as alpha-enolase, annexin A2, and macrophage capping protein (MCP). Sera from FVRCP and CRFK inoculated cats were confirmed to recognize annexin A2 and alpha-enolase by Western blot immunoassay and indirect ELISA.

CONCLUSIONS AND CLINICAL RELEVANCE

This study validated the use of Western blot immunoassay for detection of antibodies against CRFK proteins and identified 3 CRFK antigens. In humans, alpha-enolase antibodies are nephritogenic; alpha-enolase and annexin A2 antibodies have been associated with autoimmune diseases. Further research will be necessary to determine the clinical relevance of these findings.

Long-term fade study of the DT-702 LiF: Mg,Cu,P TLD

LiF thermoluminescent dosemeters (TLDs) are used by the US Navy to record radiation exposure of personnel. The Model DT-648 LiF:Mg,Ti TLD has been replaced by a new Model DT-702 LiF:Mg,Cu,P TLD. The DT-648 was used for many years and has undergone extensive testing to identify its pre- and post-irradiation fade operating characteristics. Studies have shown that the addition of copper increases the thermoluminesence sensitivity of the TLD for improved low-level radiation monitoring. This study evaluates various fading characteristics of the new copper-doped dosemeter using current equipment for processing of TLDs and calibrating to a National Institute of Standards and Technology standard source. The 57-week study took place at the Naval Dosimetry Center, Bethesda, MD, USA. TLDs were stored for various lengths of time before and after being exposed to a National Institute of Standards and Technology calibrated radiation sources. TLDs were then processed using current US Navy instructions and the resulting dose compared with the calibrated exposure. Both loss of signal and loss of sensitivity were evaluated. The results of this study have shown that the DT-702 TLD has no statistically significant change in sensitivity or change in signal with up to 57 weeks of pre- or post-irradiation time. The results of this study will increase the accuracy of exposure record keeping for the Navy and will allow longer issue periods. This will increase flexibility with international and domestic shipping procedures, as well as reduce workload requirements for dosimetry processing.