New assays to measure equine influenza virus-specific Type 1 immunity in horses

Equine influenza virus (EIV) is a leading cause of respiratory disease in horses. Equine influenza infection induces a long-term immunity to re-infection. Recent strategies of vaccination aim to mimic this immunity by stimulating both antibody and cellular immune responses. Cell-mediated immunity (CMI) to influenza is well defined in man, but little has been done to characterise the responses in the horse. Additionally, the development of reliable assays for the measurement of equine CMI has lagged behind serological methods and vaccine development. In this study, two methods of measuring EIV-specific T lymphocyte responses have been developed. An EIV 'bulk' cytotoxic T lymphocytes (CTL) assay using equine dermal fibroblasts as target cells has been adapted from a method used in the 1980s. This method was also complemented with a new EIV-specific IFNgamma synthesis assay. When compared with the measurement of EIV-specific IFNgamma synthesis previously described, this method required the amplification of EIV-specific lymphocytes by culture and was sensitive enough to detect stimulation of EIV-specific T lymphocytes induced by experimental infection with EIV or vaccination with recombinant canarypox viruses coding for EIV-HA molecules. This study provides the tools to characterise the stimulation of CMI by the new generation of vaccines against equine influenza.

Description of the outbreak of equine influenza (H3N8) in the United Kingdom in 2003, during which recently vaccinated horses in Newmarket developed respiratory disease

Between March and May 2003, equine influenza virus infection was confirmed as the cause of clinical respiratory disease among both vaccinated and unvaccinated horses of different breeds and types in at least 12 locations in the UK. In the largest outbreak, 21 thoroughbred training yards in Newmarket, with more than 1300 racehorses, were affected, with the horses showing signs of coughing and nasal discharge during a period of nine weeks. Many of the infected horses had been vaccinated during the previous three months with a vaccine that contained representatives from both the European (A/eq/Newmarket/2/93) and American (A/eq/Newmarket/1/93) H3NN8 influenza virus lineages. Antigenic and genetic characterisation of the viruses from Newmarket and elsewhere indicated that they were all closely related to representatives of a sublineage of American viruses, for example, Kentucky/5/02, the first time that this sublineage had been isolated in the uk. In the recently vaccinated racehorses in Newmarket the single radial haemolysis antibody levels in acute sera appeared to be adequate, and there did not appear to be significant antigenic differences between the infecting virus and A/eq/Newmarket/1/93, the representative of the American lineage virus present in the most widely used vaccine, to explain the vaccine failure. However, there was evidence for significantly fewer infections among two-year-old horses than older animals, despite their having similar high levels of antibody, consistent with a qualitative rather than a quantitative difference in the immunity conveyed by the vaccination.

APS participatory network case study review

The goal of this project was to establish the feasibility of linking a practice-based research network of Adult Protective Service (APS) workers to an academic institution. To determine whether this newly formed APS research network was feasible, a qualitative research project was attempted with network members who had e-mail. An e-mailed single case study with three questions sent to the 356 network members yielded a 31% return rate. APS workers suggested 73 different ideal and actual services for the case study abuse victim. Half of the respondents were unable to implement the ideal service. Barriers were predominantly financial, victim and daughter cooperation, and availability of resources. It is realistic and feasible to establish an adult protective service research network with an interdisciplinary academic research team.

Antibody and IFN-γ responses induced by a recombinant canarypox vaccine and challenge infection with equine influenza virus

In horses, equine influenza virus (EIV) is a leading cause of respiratory disease. Conventional inactivated vaccines induce a short-lived immune response. By comparison, natural infection confers a long-term immunity to re-infection. An aim of new equine influenza vaccines is to more closely mimic natural infection in order to achieve a better quality of immunity. A new live recombinant vaccine derived from the canarypox virus vector and expressing haemagglutinin genes of EIV (subtype H3N8) has been developed. Stimulation of the immune system was studied after immunisation with this canarypox-based vaccine and challenge infection by exposure to a nebulised aerosol of EIV. The humoral immune response was evaluated by measuring serum antibody levels using the single radial haemolysis (SRH) assay. The cellular immune response was assessed by the measurement of interferon gamma (IFN-gamma) synthesis in peripheral blood mononuclear cells (PBMC). Clinical signs of the disease (temperature, coughing, nasal discharge, dyspnoea, depression and anorexia) and virus excretion were monitored after challenge infection. Clinical signs and virus shedding were significantly reduced in vaccinates compared with unvaccinated controls. EIV-specific immunity was stimulated by vaccination with a recombinant vaccine as serological responses were detected after immunisation. This study also provided the first evidence for increased IFN-gamma protein synthesis in vaccinated ponies following challenge infection with EIV compared with control ponies.

Vaccination against equine influenza: Quid novi?

Equine influenza virus is a leading cause of respiratory disease in the horse. Equine influenza vaccines containing inactivated virus were first developed in the 1960s. Despite their intensive use, equine influenza outbreaks still continue to occur and therefore new strategies of vaccination are necessary to improve vaccine efficacy. Numerous methods of vaccination have been evaluated and commercialised in the horse, the most recent being the cold-adapted influenza virus and poxvirus-based vaccines. As a large animal model, the horse is also a useful species in which to evaluate the potential of new generations of influenza vaccine such as live-attenuated influenza virus engineered by reverse genetics. This report details the equine immune responses conferring protection against influenza. It then undertakes a selective review of different strategies of vaccination against equine influenza that have been developed over the last two decades and discusses factors that may influence the efficacy of vaccination. Finally it outlines progress in the development of a novel vaccination strategy against equine influenza using reverse genetics.

Characterisation of CTL and IFN-γ synthesis in ponies following vaccination with a NYVAC-based construct coding for EHV-1 immediate early gene, followed by challenge infection

Equine herpesvirus-1 (EHV-1) is a ubiquitous pathogen of horses, which continues to cause respiratory and neurological disease and abortion, despite the widespread use of vaccines. Cell mediated immunity (CMI) is thought to play a major role in protection against infection with EHV-1. The aim of this study was to characterise the virus-specific CMI response in ponies vaccinated with vP1014, a vaccinia-based construct (NYVAC) coding for the immediate early gene (gene 64) of EHV-1. This gene product is a CTL target protein for an equine MHC class I allele expressed on the A3 haplotype. EHV-primed yearling ponies expressing this haplotype were vaccinated once (n = 1), three (n = 1), or four times (n = 2), and one pony was kept as an unvaccinated control. Cytotoxic T lymphocyte (CTL) activity and interferon gamma (IFN-gamma) synthesis were measured before and after vaccination and challenge infection with EHV-1. Multiple immunisations with vP1014 resulted in increased CTL activity and IFN-gamma synthesis specific for EHV-1 compared with unvaccinated or singly vaccinated ponies. The phenotype of EHV-1 specific T-cells synthesising IFN-gamma was also modified by immunisation. In the unvaccinated pony, the predominant population synthesising IFN-gamma after EHV-1 stimulation was CD8alpha+. In contrast, multiply vaccinated ponies demonstrated an increased proportion of CD8alpha- T-cells synthesising IFN-gamma. The results demonstrated that vaccination with a NYVAC-based construct coding for gene 64 stimulated CMI. This immune response alone did not protect against challenge infection. However, the study does illustrate that vaccinia-based vaccines can stimulate CMI in the horse and may therefore contribute to protection against disease caused by EHV-1.

Iowa nursing home characteristics associated with reported abuse

OBJECTIVE

To evaluate the association of nursing home abuse reported by employees in Iowa licensed nursing homes with nursing home characteristics, inspection results, nursing staff hours, and census demographics.

DESIGN

Mailed survey.

SETTING

Iowa's 409 Medicare-certified stand-alone nursing homes.

PARTICIPANTS

Administrators and directors of nursing.

RESULTS

The annual rate of abusive events was 20.7 per 1000 nursing home residents, with a rate of 18.4 reported events and 5.2 substantiated events. A higher number of residents and a higher number of certified beds were significantly associated with higher incident, report, and substantiation rates. Higher incident and report rates were associated with nursing homes in metropolitan areas. Higher substantiation rates were associated with for-profit nursing homes.

CONCLUSION

Recognized abuse in nursing homes is not uncommon. Approximately 90% of events are reported to the state authorities with 29% of those being substantiated. Differences associated with nursing facility abuse rates are metropolitan area, ownership, occupancy rate, and number of residents and certified beds.

Investigation of Equine Influenza Cases Exhibiting Neurological Disease: Coincidence or Association?

Equine influenza is usually a transient and self-limiting disease. However, during an outbreak of equine influenza in the UK in 2003 there were reports of unusually severe clinical signs among unvaccinated animals. Two influenza-infected horses developed neurological signs, and one was subjected to euthanasia. Post-mortem examination of the brain revealed viral-type non-suppurative encephalitis, and influenza virus antigen was demonstrated by immunolabelling of sections of nasal mucosa. A syndrome known as influenza-associated encephalopathy has been described in man. Although not proved, the data suggest that similar disease mechanisms may operate in horses, and that equine influenza virus infection can result in encephalitis in the natural host, perhaps due to an aberrant host immune response.

Association of knowledge of adult protective services legislation with rates of reporting of abuse in Iowa nursing homes

OBJECTIVE

To determine if there is an association between abuse reporting to state authorities by nursing home administrators and directors of nursing and their characteristics and knowledge of the law.

DESIGN

Survey.

SETTING

Iowa's 409 Medicare certified nursing homes.

PARTICIPANTS

Four hundred nine administrators and 409 directors of nursing.

MEASUREMENTS

Nursing home abuse incidents, reports, and substantiations, Medicare's Nursing Home Compare Reports, Urban Influence Codes, and county census demographics.

RESULTS

A single or double response was received from 369 (90%) of the 409 nursing homes. Being a male administrator and having a higher level of education is associated with higher substantiation rates. A greater knowledge of the dependent adult protective services law is associated with higher incident and report rates for directors of nursing.

CONCLUSIONS

Nursing home administrators' and directors of nursing's knowledge of the law and their characteristics are associated with nursing home incident, report, and substantiation of abuse allegations.

A nursing home telehealth system: keeping residents connected

Live video and detailed images of nursing home residents can be transmitted in real time via the Internet. This telehealth system allows residents and long-term care health professionals to connect with experts not available on-site. Electronic stethoscope, otoscope, dermascope, dentalscope, and electrocardiogram are available for use via the Internet. Impediments to implementing telehealth systems in long-term care include costs and the lack of reimbursement for telehealth services. Reimbursement for telemedicine in nursing homes is limited by originating site, current procedural terminology codes, and facility location.

Equine interferon gamma synthesis in lymphocytes after in vivo infection and in vitro stimulation with EHV-1

Equine cytotoxic T lymphocyte (CTL) responses to equine herpesvirus-1 (EHV-1) are well characterised but little is known about the cytokine response after infection or vaccination. EHV-1 is common in horses and infects lymphocytes in vivo. This virus was used as a model to measure the synthesis of interferon gamma (IFN-gamma) by equine peripheral blood mononuclear cells (PBMC) after in vivo infection and/or in vitro stimulation with EHV-1. Both flow cytometry and ELISPOT assays were used to quantify equine IFN-gamma using a mouse anti-bovine IFN-gamma monoclonal antibody (clone CC302; shown to cross-react with recombinant equine IFN-gamma) and a rabbit anti-canine IFN-gamma polyclonal antibody. The percentage of PBMC synthesising IFN-gamma after in vitro stimulation with EHV-1 increased with age. In yearlings infected experimentally with EHV-1, PBMC showed two peaks of IFN-gamma synthesis, 11 and 56 days after infection. The IFN-gamma synthesis was principally associated with CD8(+) cells. The patterns of IFN-gamma synthesis detected by intracellular IFN-gamma staining or ELISPOT were compared with CTL data and shown to be similar. These methods were also applied successfully to frozen samples of PBMC. Measurement of equine IFN-gamma using these simple techniques can now be applied to future studies on protective cellular immune responses following virus infection and/or vaccination of horses.

APS workers job requirements associated with elder abuse rates

The purpose of this paper is to evaluate the relationship of required educational background of APS workers to the 1999 rates of domestic elder abuse. Data were obtained from APS related statutes and regulations and questions to the National Center for Elder Abuse list serve. Descriptive statistics and independent sample t-tests were used for analyses. Those states whose legislations required a social work degree for APS caseworkers did have higher elder abuse investigation rates. A lower substantiation ratio was found for those states requiring a social work degree or license. These findings suggest that social work education may lead to an emphasis on investigation and interventions and de-emphasis on the criminal aspects of elder abuse evaluation substantiations.

The effects of strain heterology on the epidemiology of equine influenza in a vaccinated population

We assess the effects of strain heterology (strains that are immunologically similar but not identical) on equine influenza in a vaccinated population. Using data relating to individual animals, for both homologous and heterologous vaccinees, we estimate distributions for the latent and infectious periods, quantify the risk of becoming infected in terms of the quantity of cross-reactive antibodies to a key surface protein of the virus (haemagglutinin) and estimate the probability of excreting virus (i.e. becoming infectious) given that infection has occurred. The data suggest that the infectious period, the risk of becoming infected (for a given vaccine-induced level of cross-reactive antibodies) and the probability of excreting virus are increased for heterologously vaccinated animals when compared with homologously vaccinated animals. The data are used to parameterize a modified susceptible, exposed, infectious and recovered/resistant (SEIR) model, which shows that these relatively small differences combine to have a large effect at the population level, where populations of heterologous vaccinees face a significantly increased risk of an epidemic occurring.

Domestic elder abuse and the law

OBJECTIVES

The authors evaluated the impact of state adult protective service legislation on rates of investigated and substantiated domestic elder abuse.

METHODS

Data were collected on all domestic elder abuse reports, investigations, and substantiations for each US state and the District of Columbia for 1999. State statutes and regulations pertaining to adult protective services were reviewed.

RESULTS

There were 190 005 domestic elder abuse reports from 17 states, a rate of 8.6 per 1000 elders; 242 430 domestic elder abuse investigations from 47 states, a rate of 5.9; and 102 879 substantiations from 35 states, a rate of 2.7. Significantly higher investigation rates were found for states requiring mandatory reporting and tracking of numbers of reports.

CONCLUSIONS

Domestic elder abuse documentation among states shows substantial differences related to specific aspects of state laws.

Public forums to advance dependent adult abuse policy

Sponsored forums were hosted to obtain the opinions of invited professionals on how to create the ideal system for protecting dependent adults in Iowa. The purpose of the study was to determine how the forum participants perceive change in the adult protective service system five years after the forums were held. A mailed sixty-nine-item questionnaire sent to the 1,000 forum participants and professionals in the aging network yielded a 30 percent return rate. Ninety-four percent of the items were ranked by more than half of the respondents as important with abuse awareness items scoring the highest. For each item approximately half of the respondents indicated they did not know if a change had occurred.

Comparison of hamster and pony challenge models for evaluation of effect of antigenic drift on cross protection afforded by equine influenza vaccines

REASONS FOR PERFORMING STUDY

Vaccination and challenge studies in ponies are the most relevant experimental system for predicting whether strains included in equine influenza vaccines are relevant, but they are difficult to perform.

OBJECTIVES

In order to investigate the feasibility of using a small animal model, results of a cross-protection study in hamsters were compared with those from a previous pony challenge experiment.

METHODS

Animals were immunised with inactivated vaccines containing one of 4 strains of equine influenza A H3N8 subtype virus isolated over a 26 year period (1963 to 1989), then challenged with a 1989 strain.

RESULTS

Although there was no significant difference in titres of excreted virus between groups of vaccinated ponies, hamsters immunised with heterologous strains had significantly higher virus titres in the lung than hamsters vaccinated with the homologous strain. In both ponies and hamsters, the number of animals excreting virus was greater the earlier the isolation date of the vaccine strain, although this was only significant in the hamster study.

CONCLUSIONS

Despite differences, the overall conclusion of both the pony and hamster models was that heterologous vaccines may be less effective than homologous vaccines at preventing virus excretion.

POTENTIAL RELEVANCE

Further validation is required, but the hamster model shows potential for preliminary assessment of the effects of antigenic drift on vaccine efficacy.

Diagnostic methods applied to analysis of an outbreak of equine influenza in a riding school in which vaccine failure occurred

An outbreak of equine influenza H3N8 in a riding school is described retrospectively with emphasis on diagnosis and putative vaccine failure. In March 1995 an outbreak of equine influenza occurred among 11 horses in a riding school, where most horses had received basic primary immunizations and several booster vaccinations against influenza. Six of the 11 diseased horses had received their last booster vaccination within 5 months of the outbreak. Nevertheless, the influenza infection spread rapidly and clinical manifestations were prominent with frequent, harsh, dry coughing often accompanied by high fever. Nasal swabs were taken from 11 diseased horses. Influenza A virus of the equine H3N8 (equi-2) subtype was isolated from five nasal swab extracts. Stored nasal swab extracts were also retrospectively investigated in two different enzyme immunoassays designed to detect the type-specific conserved nucleoprotein of influenza A viruses, and in a single-tube reverse transcription-PCR (RT-PCR) using a set of primers based on highly conserved regions of the matrix gene of influenza A viruses. Five nasal swab extracts were found positive in a DAS-ELISA and seven in the Directigen((R)) Flu A (DFA) assay, respectively. Two nasal swab extracts from which virus was isolated did not give a positive result in the DAS-ELISA, and one of these also did not give a positive result in the DFA assay. Nine nasal swab extracts were found positive by RT-PCR. Moreover, all virus isolation and/or ELISA positive nasal swab extracts were confirmed by RT-PCR. Three nasal swab extracts were negative by virus isolation, PCR and ELISA. A significant rise in HI titre against influenza A/eq/Miami/63 (H3N8) virus was detected in seven of the nine paired sera available. In acute phase serum samples from 10 horses, SRH antibody levels varied widely. However, some horses with high, or at least putatively clinically protective SRH antibody levels, showed clinical signs and infection was confirmed. Antigenic analysis of two isolates showed that A/eq/Holland/1/95 (H3N8) and A/eq/Holland/2/95 (H3N8) cluster with the UK isolate Osgodsby/92, the Swedish isolate Borlänge/91 and some other European isolates, with H/2/95 identical in reactivity to Borlänge/91 and H/1/95 more similar in reactivity to Osgodsby/92 than H/2/95. Nucleotide and deduced amino-acid sequences showed large differences of both isolates as compared with Miami/63, Fontainebleau/79 and Kentucky/81, the influenza A H3N8 subtype strains incorporated in the vaccines used in this riding school. The role of antigenic drift in vaccine breakdown is discussed in the light of evidence for vaccine breakdown in the UK in 1989, Sweden in 1991 and in the USA since 1991.

Hand-assisted laparoscopic splenectomy for giant spleens

BACKGROUND

Laparoscopic splenectomy for massive splenomegaly is technically difficult, and the morcellated splenic tissue may be inadequate for histologic study. A hand-assisted technique may provide a technical advantage and allow removal of larger pieces of spleen.

METHODS

Patients who underwent hand-assisted laparoscopic splenectomy for massive splenomegaly were reviewed. Demographic information, operative data, and outcomes data were tabulated.

RESULTS

Sixteen patients met these criteria. Mean age was 56 years (range, 35-78 years). Operating time averaged 240 min (range, 165-360 min), and median blood loss was 425 cc (range, 100-1800 cc). There were no conversions to an open procedure. Mean weight of extracted spleens was 2008 g (range, 543-4090 g). Postoperative length of stay averaged 3.3 days (range, 2-7 days). There was one postoperative complication (6.25%) and no mortality.

CONCLUSIONS

Hand-assisted laparoscopic splenectomy for massive splenomegaly is feasible and safe while preserving the recovery benefits of minimal access surgery. It provides an adequate specimen for histologic study.

Screening elderly patients in an outpatient ophthalmology clinic for dementia, depression, and functional impairment

PURPOSE

To determine the feasibility of screening for depression, dementia, and functional impairment in an ophthalmology outpatient clinic.

DESIGN

Prospective pilot survey study.

PARTICIPANTS

Fifty consecutive ophthalmology clinic outpatients.

METHODS

Consecutive patients more than 64 years of age with visits to the comprehensive eye clinic and the neuroophthalmology clinic at the University of Iowa were assessed. Suitable subjects were asked to complete a short questionnaire on instrumental activities of daily living, to answer a single question on depression, and to complete a clock drawing task in the office waiting room or examination room.

RESULTS

The 50 questionnaires reviewed showed that most respondents were functional (94%) in instrumental activities of daily living, had normal clock drawing results (80%), and were not depressed (80%). A significant minority, however, were identified by the screening to have functional impairment (6%), abnormal clock drawing results (20%), or depression (20%), and these patients were offered geriatric assessment. The tests were rapid (fewer than 5 minutes to perform) and easy to administer.

CONCLUSIONS

Screening for geriatric syndromes in the eye clinic was rapid, easy to perform, and detected a significant number of patients with functional disability, depression, and possible dementia.

Written and computerized care plans. Organizational processes and effect on patient outcomes

The purpose of this study was to determine how use of a standardized nomenclature for nursing diagnosis and intervention statements on the computerized nursing care plan in a long-term care (LTC) facility would affect patient outcomes, as well as organizational processes and outcomes. An experimental design was used to compare the effects of two methods of documentation: Computer care plan and paper care plan. Twenty participants (10 in each group) were randomly assigned to either group. No statistically significant differences were found by group for demographic data. Repeated measures ANOVA was computed for each of the study variables with type of care plan, written or computerized, as the independent variable. There were no statistically significant differences between participants, group (care plan), within subjects (across time), or interaction (group and time) effects for the dependent variables: Level of care, activities of daily living, perception of pain, cognitive abilities, number of medications, number of bowel medications, number of constipation episodes, weight, percent of meals eaten, and incidence of alteration in skin integrity. There were significantly more nursing interventions and activities on the computerized care plan, although this care plan took longer to develop at each of the three time periods. Results from this study suggest that use of a computerized plan of care increases the number of documented nursing activities and interventions, but further research is warranted to determine if this potential advantage can be translated into improved patient and organizational outcomes in the long-term care setting.

Elevated expression of cyclooxygenase-2 contributes to immune dysfunction in a murine model of trauma

BACKGROUND

Cyclooxygenase-2 (Cox-2), the inducible form of Cox, is a rate-limiting enzyme in the synthesis of prostaglandins (PGs). Prostaglandin E2 (PGE2) and other eicosanoids possess immunosuppressive properties. Previously, traumatic injury was found to stimulate the synthesis of PGs and cause immune dysfunction. In this study a murine model was used to determine the effect of trauma on the expression of Cox-2 in macrophages and to elucidate the role of Cox-2 in trauma-induced immune dysfunction.

METHODS

Mice were randomized to control or trauma (femur fracture plus 40% blood volume hemorrhage) groups. One, 4, and 7 days after injury, splenic macrophages were isolated and assayed for expression of Cox-2 and production of PGE2. In addition, the effect of pharmacologically inhibiting Cox-2 or knocking out the Cox-2 gene on trauma-induced suppression of splenocyte mitogenesis was determined.

RESULTS

Trauma led to increased expression of Cox-2, enhanced synthesis of PGE2, and suppressed splenocyte mitogenesis. Both pharmacologic inhibition and genetic deletion of Cox-2 abrogated trauma-mediated suppression of splenocyte mitogenesis.

CONCLUSIONS

These experiments link trauma-induced increases in Cox-2 expression and PGE2 production to reduced immune function. Cox-2 represents a potential pharmacologic target to prevent or reverse trauma-induced immunosuppression.