Survival of rabid rabbits after intrathecal immunization

Rabies is a fatal zoonotic disease for which no effective treatment measures are currently available. Rabies virus (RABV) has anti‐apoptotic and anti‐inflammatory properties that suppress nerve cell damage and inflammation in the CNS. These features imply that the elimination of RABV from the CNS by appropriate treatment could lead to complete recovery from rabies. Ten rabbits showing neuromuscular symptoms of rabies after subcutaneous (SC) immunization using commercially available vaccine containing inactivated whole RABV particles and subsequent fixed RABV (CVS strain) inoculation into hind limb muscles were allocated into three groups. Three rabbits received no further treatment (the SC group), three rabbits received three additional SC immunizations using the same vaccine, and four rabbits received three intrathecal (IT) immunizations, in which the vaccine was inoculated directly into the cerebrospinal fluid (the SC/IT group). An additional three naïve rabbits were inoculated intramuscularly with RABV and not vaccinated. The rabbits exhibited neuromuscular symptoms of rabies within 4–8 days post‐inoculation (dpi) of RABV. All of the rabbits died within 8–12 dpi with the exception of one rabbit in the SC group and all four rabbits in SC/IT group, which recovered and started to respond to external stimuli at 11–18 dpi and survived until the end of the experimental period. RABV was eliminated from the CNS of the surviving rabbits. We report here a possible, although still incomplete, therapy for rabies using IT immunization. Our protocol may rescue the life of rabid patients and prompt the future development of novel therapies against rabies.     

Chinese-like Strain of Porcine Epidemic Diarrhea Virus, Thailand

Since late 2007, several outbreaks of porcine epidemic diarrhea virus (PEDV) infection have emerged in Thailand. Phylogenetic analysis places all Thai PEDV isolates during the outbreaks in the same clade as the Chinese strain JS-2004-2. This new genotype PEDV is prevailing and currently causing sporadic outbreaks in Thailand.     

Probable tiger-to-tiger transmission of avian influenza H5N1

During the second outbreak of avian influenza H5N1 in Thailand, probable horizontal transmission among tigers was demonstrated in the tiger zoo. Sequencing and phylogenetic analysis of those viruses showed no differences from the first isolate obtained in January 2004. This finding has implications for influenza virus epidemiology and pathogenicity in mammals.     

Ex vivo generation of cytokine-induced killer cells (CD3+ CD56+) from post-stem cell transplant pediatric patients against autologous-Epstein-Barr virus-transformed lymphoblastoid cell lines

EBV-PTLDs affect as high as 20% of SCT recipients especially those with T-cell depleted grafts while high mortality rates were also noted. Adoptive allogeneic and autologous CTLs have a therapeutic potential in this setting. However, the process of expansion of these cells is tedious and time consuming in both allogeneic and autologous CTL generation. For the allogeneic SCT, another major obstacle is unavailability of donors especially in an unrelated SCT setting. The aim of the present study was therefore to investigate the efficacy of autologous CIK cells (CD3+ CD56+) against autologous EBV-LCLs from post-SCT pediatric patients. We could demonstrate that CIK cells can be generated within two wk and did show the significant cytotoxicity against autologous EBV-LCLs. CIK cells may provide a potent tool for use in post-transplantation adoptive immunotherapy.     

Factors affecting the incidence of cystic ovaries in replacement gilts

The aim of the present study was to investigate the incidence of cystic ovaries in replacement gilts in relation to age, body weight, estrus behavior, season, and reasons for culling. Data and genital organs of 336 slaughtered gilts from six commercial herds in Thailand were investigated. The reproductive organs were collected at the slaughter house and transported on ice to the laboratory within 24 h for post-mortem examination. Cystic ovaries were characterized by the presence of single or multiple cysts whether accompanied by any other normal structure or not. Cystic ovaries were observed in 44 of 336 (13.1%) gilts. Of these gilts, 26 (59.1%) gilts had multiple cysts and 18 (40.9%) gilts had single cysts. Gilts culled due to abnormal vaginal discharge were more likely to have cysts than gilts culled due to anestrus (19.4% versus 9.1%, P = 0.043). The gilts that were culled at a body weight of ≥161 kg had a higher incidence of cystic ovaries than gilts culled at a body weight of ≤130 kg (8.1% versus 20.3%, P = 0.045). The incidence of cystic ovaries was lower in those that had not shown estrus than those that had shown estrus (5.2% versus 19.7%, P < 0.001). The incidence of cystic ovaries tended to be higher in the gilts culled in cool (18.6%) compared to hot (10.0%, P = 0.092) and rainy (11.4%, P = 0.129) seasons.     

Negative impact of porcine reproductive and respiratory syndrome virus infection on the efficacy of classical swine fever vaccine

Recent findings suggest that porcine reproductive and respiratory syndrome virus (PRRSV) possesses immunomodulatory properties. To investigate the effect of PRRSV infection on classical swine fever (CSF) vaccine efficacy, 17-day-old pigs were divided into five groups. The experimental group was infected with a Thai PRRSV (US genotype) a week before CSF vaccination and challenged with a virulent CSF virus (CSFV) 3 weeks following vaccination. The control groups received no PRRSV infection, no CSF vaccination, no CSF challenge, or in combination were included. The results demonstrated that PRRSV infection significantly inhibited host immune response that resulted in vaccination failure in the subsequent CSFV exposure. Following CSF challenge, the PRRSV-infected, vaccinated pigs exhibited clinical, virological and pathological features resembled to those of the non-vaccinated groups. The findings indicated that CSF immunization during an acute phase of PRRSV infection could result in vaccination failure.