Oral vaccination of Nile tilapia (Oreochromis niloticus) against francisellosis elevates specific antibody titres in serum and mucus.

Although Nile tilapia (Oreochromis niloticus) is a well-established aquaculture species globally, there are a limited number of commercial vaccines available or are used for this species. The majority of diseases affecting farmed tilapia are bacterial, with antibiotics frequently used to treat fish. The current study was performed to optimise the use of mucosal vaccines for tilapia by adapting an existing bacterin vaccine against Francisella noatunensis subsp. orientalis (Fno) as a proof of concept. This vaccine has previously provided excellent protection by injection, however, the preference for tilapia farmers would be to vaccinate fish by immersion or orally, due to the lower cost and ease of application. These vaccination routes, however, are often less efficacious probably due to the lack of adjuvants in immersion and oral vaccines. The aims of this study, therefore, were to optimise the formulation and dose of the Fno vaccine with mucosal adjuvants for oral and immersion delivery. Tilapia fry (av. 6 g) were given three concentrations (high, medium, low; i.e. 1×109, 1×108 and 1×107 CFU mL-1) of antigen combined with the oral adjuvant by oral gavage, to optimise the dose needed to induce an immune response to Fno, and the immune response obtained compared with fish vaccinated by immersion (with and without an immersion adjuvant). Fry were boosted by the same route at 420 degree days (DD), and samples (serum, mucus ) taken at 840 DD for specific antibody responses measured by ELISA and western blotting. Specific IgM titres were significantly elevated in serum and mucus of fish given the high dose adjuvanted vaccine by gavage. In addition, by western blotting with serum, a significant immunogenic reaction was evident between 20 and 37 kDa in the fish given the high dose oral vaccine by gavage. As protection against Fno provided by the injection vaccine was correlated with specific antibody responses these findings suggest the oral vaccine also has potential to provide protection. Further studies are needed to optimise delivery of the vaccine via feed.

Efficacy and safety of a non-mineral oil adjuvanted injectable vaccine for the protection of Atlantic salmon (Salmo salar L.) against Flavobacterium psychrophilum.

Flavobacterium psychrophilum is the causative agent of Rainbow Trout Fry Syndrome which has had a major impact on global salmonid aquaculture. Recent outbreaks in Atlantic salmon in Scotland and Chile have added to the need for a vaccine to protect both salmon and trout. At present no licensed vaccines are available in Europe, leaving antibiotics as the only course of action to contain disease outbreaks. Outbreaks generally occur in fry at temperatures between 10 and 15 °C. Recently outbreaks in larger fish have given added impetus to the development of a vaccine which can provide long term protection from this highly heterogeneous pathogen. Most fish injectable vaccines are formulated with oil emulsion adjuvants to induce strong and long lasting immunity, but which are known to cause side effects. Alternative adjuvants are currently sought to minimise these adverse effects. The current study was performed to assess the efficacy of a polyvalent, whole cell vaccine containing formalin-inactivated F. psychrophilum to induce protective immunity in Atlantic salmon. The vaccine was formulated with an adjuvant containing squalene and aluminium hydroxide, and was compared to a vaccine formulated with a traditional oil adjuvant, Montanide ISA 760VG, and a non-adjuvanted vaccine. Duplicate groups of salmon (23.5 ± 6.8 g) were vaccinated with each of the vaccine formulations or phosphate buffered saline by intraperitoneal injection. Fish were challenged by intramuscular injection with F. psychrophilum six weeks post-vaccination to test the efficacy of the vaccines. Cumulative mortality reached 70% in the control salmon, while the groups of salmon that received vaccine had significantly lower mortality than the controls (p = 0.0001), with no significant difference in survival between vaccinated groups. The squalene/alum adjuvant was safe, more readily metabolised by the fish and induced less histopathological changes than the traditional oil adjuvant.

Characterization of the outer membrane proteome of Francisella noatunensis subsp. orientalis.

AIMS: The aims of the current study were to characterize the outer membrane proteins (OMPs) of Francisella noatunensis subsp. orientalis (Fno) STIR-GUS-F2f7, and identify proteins recognized by sera from tilapia, Oreochromis niloticus, (L) that survived experimental challenge with Fno. METHODS AND RESULTS: The composition of the OMPs of a virulent strain of Fno (STIR-GUS-F2f7), isolated from diseased red Nile tilapia in the United Kingdom, was examined. The sarcosine-insoluble OMPs fraction was screened with tilapia hyperimmune sera by western blot analysis following separation of the proteins by 1D SDS-PAGE. Liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) was used to identify the various proteins present in the OMP profile. Two hundred and thirty-nine proteins were identified, of which 44 were found in the immunogenic band recognized by the tilapia hyperimmune serum. In silico analysis was performed to predict the function and location of the OMPs identified by MS. CONCLUSIONS: Using a powerful proteomic-based approach in conjugation with western immunoblotting, proteins comprising the outer membrane fraction of Fno STIR-GUS-F2f7 were identified, catalogued and screened for immune recognition by tilapia sera. SIGNIFICANCE AND IMPACT OF THE STUDY: The current study is the first report on the characterization of Fno-OMPs. The findings here provide preliminary data on bacterial surface proteins that exist in direct contact with the host's immune defences during infection and offer an insight into the pathogenesis of Fno.

Antimicrobial susceptibility of Flavobacterium psychrophilum isolates from the United Kingdom.

Routine application of antimicrobials is the current treatment of choice for rainbow trout fry syndrome (RTFS) or bacterial coldwater disease (BCWD) caused by Flavobacterium psychrophilum. In this study, the antimicrobial susceptibilities of 133 F. psychrophilum isolates, 118 of which were from the UK, were evaluated by broth microdilution and disc diffusion methods following VET04-A2 and VET03-A guidelines of Clinical and Laboratory Standards Institute (CLSI), respectively. Isolates were categorized as wild type (fully susceptible, WT) or non-wild type (NWT) using normalized resistance interpretation (NRI)-determined cut-off values (COWT ). Broth microdilution testing showed that only 12% of UK isolates were WT to oxolinic acid (MIC COWT  ≤ 0.25 mg/L) and 42% were WT for oxytetracycline (MIC COWT  ≤ 0.25 mg/L). In contrast, all the isolates tested were WT (MIC COWT  ≤ 2 mg/L) for florfenicol, the main antimicrobial for RTFS control in the UK. Disc diffusion-based COWT values were ≥51 mm for 10 µg amoxicillin, ≥44 mm for 30 µg florfenicol, ≥30 mm for 2 µg oxolinic acid and ≥51 mm for 30 µg oxytetracycline. There was a high categorical agreement between the classifications of the isolates by two testing methods for florfenicol (100%), oxytetracycline (93%) and oxolinic acid (99%).

Efficacy of a polyvalent immersion vaccine against Flavobacterium psychrophilum and evaluation of immune response to vaccination in rainbow trout fry (Onchorynchus mykiss L.).

Rainbow trout fry syndrome (RTFS) is a disease caused by the Gram-negative bacterium Flavobacterium psychrophilum, responsible for significant economic losses in salmonid aquaculture worldwide. The diversity of F. psychrophilum isolates and the inherent difficulties in vaccinating juvenile fish has hampered the development of a vaccine for RTFS. Disease episodes tend to occur between 10-14 °C with necrotic lesions often seen on the skin surrounding the dorsal fin and tail. At present no commercial vaccines are available for RTFS in the UK, leaving antibiotics as the only course of action to control disease outbreaks. The current work was performed as a pilot study to assess the efficacy of a polyvalent, whole cell vaccine containing formalin-inactivated F. psychrophilum, to induce protective immunity in rainbow trout fry. Duplicate groups of 30 trout (5 g) were immersed in 1 L of the vaccine for 30 s. Samples were taken 4 h, day 2 and 7 post-vaccination (pv) of skin mucus, tissues for histology and gene expression analysis; serum and histology samples were taken 6 weeks pv. A booster vaccination was given at 315 degree days (dd) also by immersion. Challenge was by immersion with a heterologous isolate of F. psychrophilum 630 dd post primary vaccination. The vaccine provided significant protection to the trout fry with a RPS of 84% (p < 0.0001). Detection of increased numbers of IgT positive cells in systemic organs, up-regulation of IgT expression in hind-gut and an increase in total IgT in serum was observed in vaccinated fish; however a functional role of IgT in the observed protection remains to be demonstrated.

Treponema infection associated with genital ulceration in wild baboons.

The authors describe genital alterations and detailed histologic findings in baboons naturally infected with Treponema pallidum. The disease causes moderate to severe genital ulcerations in a population of olive baboons (Papio hamadryas anubis) at Lake Manyara National Park in Tanzania. In a field survey in 2007, 63 individuals of all age classes, both sexes, and different grades of infection were chemically immobilized and sampled. Histology and molecular biological tests were used to detect and identify the organism responsible: a strain similar to T pallidum ssp pertenue, the cause of yaws in humans. Although treponemal infections are not a new phenomenon in nonhuman primates, the infection described here appears to be strictly associated with the anogenital region and results in tissue alterations matching those found in human syphilis infections (caused by T pallidum ssp pallidum), despite the causative pathogen's greater genetic similarity to human yaws-causing strains.

Predicting CD4 T-Cell Reconstitution Following Pediatric Hematopoietic Stem Cell Transplantation.

Hematopoietic stem cell transplantation (HSCT) is an increasingly common treatment for children with a range of hematological disorders. Conditioning with cytotoxic chemotherapy and total body irradiation leaves patients severely immunocompromised. T-cell reconstitution can take several years due to delayed restoration of thymic output. Understanding T-cell reconstitution in children is complicated by normal immune system maturation, heterogeneous diagnoses, and sparse uneven sampling due to the long time spans involved. We describe here a mechanistic mathematical model for CD4 T-cell immune reconstitution following pediatric transplantation. Including relevant biology and using mixed-effects modeling allowed the factors affecting reconstitution to be identified. Bayesian predictions for the long-term reconstitution trajectories of individual children were then obtained using early post-transplant data. The model was developed using data from 288 children; its predictive ability validated on data from a further 75 children, with long-term reconstitution predicted accurately in 81% of the patients.

Development, Characterisation and Application of Monoclonal Antibodies for the Detection and Quantification of Infectious Salmon Anaemia Virus in Plasma Samples Using Luminex Bead Array Technology.

Infectious salmon anaemia virus (ISAV) is an orthomyxovirus that has had a significant economic impact on Atlantic salmon farming in Europe, North America and Chile. Monoclonal antibodies (mAbs) were developed against Segment 3 (encoding the viral nucleoprotein, NP) of the virus. Six of the mAbs were shown to be specific to ISAV and recognised all isolates from Scotland, Norway and Canada. They reacted with ISAV in enzyme-linked immunosorbent assay (ELISA), indirect fluorescent antibody technique (IFAT) and western blotting. They were also used to develop a novel detection method based on Luminex (Bio-Plex) bead-based flow cytometric technology for the detection of ISAV in the plasma of Atlantic salmon (Salmo salar L.) smolts experimentally infected with ISAV. Fish were challenged by intraperitoneal (i.p.) injection of virus at 50% Tissue Culture Infective Dose (TCID50) = 2.8 x106 per animal. Virus present in plasma of infected fish, collected at 0, 4, 8, 12, 16, 21 and 28 days post infection using a non-lethal sampling method (n = 12 at each time point), was quantified using the optimised Bio-Plex assay. The results obtained with this assay were compared with absolute quantification of the virus by RT-qPCR using SYBR Green I and TaqMan chemistries. The Bio-Plex assay developed using the NP mAbs appears to be a rapid, sensitive method for detecting and quantifying ISAV in small volumes of fish plasma and has the potential to be multiplexed for the detection of other fish pathogens (e.g. during co-infections). To our knowledge this is the first report of the use of Luminex (Bio-Plex) technology for the detection of a fish pathogen.

Allogeneic bone marrow transplantation for fucosidosis.

Bone marrow transplantation was performed on an 8-month-old boy who was diagnosed as having fucosidosis following the diagnosis of the disease in his older brother. Although he was asymptomatic and his development was normal, abnomalities were found on an MRI scan prior to transplant. In the absence of a suitable related donor, an unrelated volunteer donor was used. Conditioning for the transplant consisted of busulphan and cyclophosphamide. Graft-versus-host disease prophylaxis consisted of in vitro T cell-depletion of the bone marrow and in vivo administration of cyclosporin. The post-transplant period was complicated by moderately severe graft-versus-host disease. Engraftment was documented by the presence of donor levels of alpha-fucosidase, donor blood group and tissue type (difference in the DQ antigen), and chromosomal polymorphism pattern of donor origin. Eighteen months after transplant, there is evidence of mild neurodevelopmental delay. By contrast, his elder sibling showed far greater developmental delay at the same age. The patient's MRI scan shows improvement. We believe this to be the first case of human fucosidosis treated by bone marrow transplantation.

Clinical correlation of CT changes in 64 Chinese patients with tuberculous meningitis.

CT changes in 64 Chinese patients with proven tuberculous meningitis were compared with the clinical features at diagnosis. In patients presenting with advanced disease, hydrocephalus and cerebral infarction were common, and the hydrocephalus in these patients was more likely to require surgery at a later date for control of raised intracranial pressure. New infarctions were only seen in follow-up scans of patients who had presented with disturbed consciousness. Meningeal enhancement, the commonest finding, and intracranial tuberculomata were not related to the severity of disease at presentation. A normal scan in a drowsy patient virtually excludes the diagnosis of tuberculous meningitis.

The influence of dosage form on aspirin kinetics: implications for acute cardiovascular use.

In this study, the pharmacokinetics of several formulations of aspirin were examined: soluble aspirin, mouth-dispersible aspirin, plain aspirin and enteric-coated aspirin granules. Blood samples were taken at frequent intervals for 24 hours after single dosing in 12 healthy volunteers and Tmax, Cmax and t1/2 measured. Cmax was significantly higher for soluble aspirin than for the other formulations and the t1/2 was shorter. The results show the rapid absorption of aspirin from a soluble formulation compared with that from plain aspirin or enteric-coated aspirin granules. Recommendations to treat patients suspected of having a heart attack as soon as possible with aspirin are now widely accepted and the present study would suggest that soluble aspirin should be the aspirin of choice in this situation.

Cerebral siderosis: a complication of anticoagulant therapy?

The authors report a case of cerebral siderosis, a rare disease that generally follows multiple small episodes of subarachnoid hemorrhage from any source, following long-term anticoagulation and minor head injury, and document the features on MR, which demonstrates characteristic hypointensity in the meninges on T2-weighted scans.

Small bowel obstruction due to postoperative adhesions: treatment patterns and associated costs in 110 hospital admissions.

The workload and costs of the emergency admissions and treatment of adhesive small bowel obstruction (ASBO) are unclear. This review details and costs the admission workload of ASBO. All admissions over a 2-year period for ASBO at two district general hospitals were identified through ICD10 diagnostic codes. Diagnostic investigations, treatment patterns, ward stay and outcome information for admissions were detailed from clinical records to develop mean cost estimates and assess the associated workload. Of the 298 admissions identified, 188 were not due to ASBO and were excluded from analysis. Of the 110 admissions detailed, 41 (37%) were treated surgically and 69 (63%) conservatively. Most admissions occurred through general practitioner referral (86.4%) to accident and emergency (90.0%). Mean (SD) length of stay was 16.3 days (11.0 days) for surgical treatment and 7.0 days (4.6 days) for conservative treatment. In-patient mortality was 9.8% for the surgical group and 7.2% for the conservative group. Costs were based on the mean values from both centres for surgical and conservative admissions and detailed according to the cost of referral and follow-up (100.98 Pounds surgical versus 102.61 Pounds conservative), hospital ward and ICU stay (3,327.48 Pounds versus 1,267.92 Pounds), theatre time (832.32 Pounds surgical only), investigations (282.73 Pounds versus 207.33 Pounds) and drug costs (133.90 Pounds versus 28.29 Pounds). Total treatment cost per admission for ASBO was 4,677.41 Pounds for surgically treated admissions and 1,606.15 Pounds for conservatively treated admissions. The impact of admissions for ASBO is considerable in terms of both costs and workload. Bed stay for these admissions represents the equivalent of almost one surgical bed per year and at least 2 days theatre time, impacting on surgical capacity and waiting lists. Adhesion prevention strategies may reduce the workload associated with ASBO. The review provides useful information for planning resource allocation.

The influence of ispaghula husk on bowel habit.

Frequency of defaecation, faecal form, straining at the start and end of defaecation, feelings of incomplete evacuation of faeces and urgency of defaecation were recorded in 69 healthy volunteers during three distinct 28-day study phases: pre-treatment, treatment with ispaghula husk and post-treatment. During treatment there was a significant increase (P < 0.001) in stool frequency and significant decreases in straining at the start (P < 0.001) and end (P < 0.001) of defaecation and in feelings of incomplete evacuation (P < 0.001). There was evidence of a beneficial residual effect after treatment had stopped. There are indications that ispaghula husk (Fybogel Orange) is of benefit in relieving constipation symptoms in apparently healthy people.

The New South Wales mastitis control program. 1. Field aspects and their effect on clinical and subclinical mastitis.

A mastitis control program based on teat dipping and dry cow therapy was evaluated in 35 herds over a 3 year period. The incidence of subclinical mastitis as detected by the Rapid Mastitis Test (RMT) fell from 34% to 12% quarters positive, a reduction of 65%. Clinical mastitis was reduced from 37 clinical cases per 100 cows in the first 3 month period to 12 clinical cases per 100 cows in the last 3 month period, a reduction of 68%. Variations in response to the program in the reduction of subclinical and clinical mastitis are discussed and the results compared with similar trials conducted overseas. The Modified Whiteside Test was used on bulk milk samples from the control herds and these results were significantly correlated with the prevalence of subclinical mastitis assessed by RMT individual quarters.

The New South Wales mastitis control program. 2. Effect upon bacterial infections.

Bacteriological examinations were made on quarter samples from cows in 35 herds over a 3 year period to monitor the response in a mastitis control program. Initially, Staphylococcus aureus predominated in 32 of the herds and the mean herd prevalence was 26%. The control measures halved this rate but there was considerable variation in response between herds. The decline occurred rapidly and there was a significant reduction (P less than 0.01) by 3 months. Streptococcus agalactiae predominated in 3 herds and the overall infection rate was 4.9%. Control measures eliminated the infection completely from most herds but reinfection occurred in 2 herds. The greatest decline occurred in the first 6 months and was significant (P less than 0.05). The measures had little effect upon Str. uberis and Str. dysgalactiae which remained fairly consistently at low levels. Initially, strains of Staph. aureus resistant to penicillin were dominant in most herds. In a minority of herds strains resistant to streptomycin predominated and in these herds there was a concurrent resistance to penicillin. These patterns did not change greatly over the control period. Resistance by Str. agalactiae to streptomycin occurred in most herds at the start of the program.

Overview of the industry and social impacts of the 2007 Australian equine influenza outbreak.

The equine influenza (EI) outbreak occurred at the worst time of the year as far as the horse industry was concerned. All horse sports and horse breeds had events planned in the spring, including those relating to qualification for the 2008 Beijing Olympic Games. These were all disrupted and many were cancelled. The social and industry impacts were extensive, and included difficulties related to communication, animal welfare, vaccination, movement restrictions, economics, as well as the psychological stresses experienced by those involved, especially those for whom their primary source of income was horse related.

Industry liaison officers in the infected states of Australia during the 2007 equine influenza outbreak.

We describe the activities of persons who were formally employed as industry liaison officers (ILOs) in the infected states of Australia during the 2007 equine influenza outbreak. The knowledge and communication skills of ILOs allowed them to function very effectively, despite most of them having received no prior training. It is arguable, however, that if ILOs had received prior training, they would have performed more effectively sooner. We suggest that more individuals need ILO training in 'peacetime' and that 'just-in-time' training packages require preparation and trial prior to outbreaks to be effective.