Non-ST-elevation myocardial infarction in the Netherlands: room for improvement!

AIM: To analyse non-ST-elevation myocardial infarction (NSTEMI) care in the Netherlands and to identify modifiable factors to improve NSTEMI healthcare. METHODS: This retrospective cohort study analysed hospital and pharmacy claims data of all NSTEMI patients in the Netherlands in 2015. The effect of percutaneous coronary intervention (PCI) during hospitalisation on 1­year mortality was investigated in the subcohort alive 4 days after NSTEMI. The effect of medical treatment on 1­year mortality was assessed in the subcohort alive 30 days after NSTEMI. The effect of age, gender and co-morbidities was evaluated. PCI during hospitalisation was defined as PCI within 72 h after NSTEMI and optimal medical treatment was defined as the combined use of an aspirin species, P2Y12 inhibitor, statin, beta-blocker and angiotensin converting enzyme inhibitor/angiotensin II receptor blocker, started within 30 days after NSTEMI. RESULTS: Data from 17,997 NSTEMI patients (age 69.6 (SD = 12.8) years, 64% male) were analysed. Of the patients alive 4 days after NSTEMI, 43% had a PCI during hospitalisation and 1­year mortality was 10%. In the subcohort alive 30 days after NSTEMI, 47% of patients were receiving optimal medical treatment at 30 days and 1­year mortality was 7%. PCI during hospitalisation (odds ratio (OR) 0.42; 95% confidence interval (CI) 0.37-0.48) and optimal medical treatment (OR 0.59; 95% CI 0.51-0.67) were associated with a lower 1­year mortality. CONCLUSION: In Dutch NSTEMI patients, use of PCI during hospitalisation and prescription of optimal medical treatment are modest. As both are independently associated with a lower 1­year mortality, this study provides direction on how to improve the quality of NSTEMI healthcare in the Netherlands.

Risk of rabies introduction by non-commercial movement of pets.

In response to a Commission request, EFSA has carried out a quantitative assessment of the risk of rabies introduction into the UK, Ireland, Sweden, and Malta due to the movement of pets incubating rabies at the time of movement. The risk that a pet is incubating rabies at the time of first vaccination is equal to the prevalence of rabies-incubating pets in the population of origin. Following induction of protective immunity by vaccination, animals already incubating rabies will still develop clinical disease as a function of time after vaccination (termed type A risk). A waiting period will reduce this risk. Afew animals may not be protected after single-shot primary vaccination. Such animals may become infected during the waiting period after vaccination. The risk of becoming infected after the first vaccination (termed type B risk) depends on the prevalence and efficiency of vaccination. Serological testing can be used to identify non-immune pets (depending on test specificity) and will therefore reduce this risk accordingly. The type A and B risks were modelled as a function of the waiting period after vaccination and fitted to a non-linear model incorporating vaccination efficiency and test specificity. The model can be used to quantify the risk of moving pets from rabies infected areas and also to investigate the effect of different control measures. In quantitative terms, the type A risk constitutes by far the major risk. Therefore, a waiting period (defined as the time spent between vaccination and pet movement to the destined country) is the major effective measure to mitigate the risk of rabies introduction due to an animal being infected before primo-vaccination. Serological testing will only add significantly to risk reduction when waiting periods exceed 100 days. Within the EU, the rabies prevalence in most countries is so low that the risk can be considered negligible. However, for some countries the risk is non-negligible.

Introduction of diabetes passports involving both patients and professionals to improve hospital outpatient diabetes care.

AIM: To investigate whether a comprehensive strategy involving both patients and professionals, with the introduction of a diabetes passport as a key component, improves diabetes care. METHODS: The first 150 consecutive patients who visited their internist for a diabetes check up at the internal medicine outpatient departments at each of nine Dutch general hospitals were included in this 1 year clustered, randomised, controlled trial. Health care professionals attended an educational meeting about the use and dissemination of the diabetes passport which is a patient held record. They also received aggregated feedback on baseline data and personal feedback. Educational meetings were also organised for patients. Patient files were used in conjunction with questionnaires to determine adherence rates. Data were analysed using multilevel regression analysis. RESULTS: Small but significant changes were found in mean HbA1c levels. In the intervention group, positive health changes for patients were found (-0.3%) when compared to those in the control group (+0.2%). Diastolic blood pressure improved slightly, but no changes were found in systolic blood pressure or cholesterol. Improvements were found with regard to levels of examination of patients' feet and in patient education. CONCLUSIONS: Efforts to improve professional practice involving both professionals and patients led to small improvements in HbA1c and diastolic blood pressure levels. Further study is needed to establish whether a better structured health care delivery, operating in a more supportive environment can enhance these effects.

Patients and nurses determine variation in adherence to guidelines at Dutch hospitals more than internists or settings.

AIMS: To measure adherence to recently developed diabetes guidelines at Dutch hospital outpatient clinics and distinguish determinants for variations in care on hospital, internist and patient levels. METHODS: Thirteen general hospitals with 58 internists recruited 1950 diabetic patients. Data were extracted from medical files (n = 1915) and from patient questionnaires (n = 1465). Multilevel logistic regression analysis was performed to explain differences in adherence rates to the guidelines. RESULTS: Adherence to process measures was high, except for the examination of feet, calculation of the body mass index and patient education activities (the mean of 12 process measures was 64%). Adherence to intermediate outcome indicators was moderate. The mean percentage of patients with HbA(1c) < 7.0% was 23%. Adherence variation on a hospital level was very small (0.6-7.9%), on an internist level moderate (0.4-18.8%) and on a patient level high (74.4-98.8%). Adherence to all process measures and most of the intermediate outcome indicators was highest in the patients seen by a diabetes specialist nurse. DISCUSSION: More focus on patient involvement in diabetic care and the contribution of diabetes specialist nurses may be important factors in improving the quality of diabetes care.

Blocking ELISA's for the distinction between antibodies against European and American strains of porcine reproductive and respiratory syndrome virus.

A double blocking ELISA was developed in order to satisfy the need for large scale serological screening for PRRS and simultaneous distinction between infection with European and American strains of PRRSV in pig herds. The Immunoperoxidase monolayer assay (IPMA) and the double blocking ELISA enabled distinction on serological basis between infection with European and American strains of PRRSV. The distinction was possible from about day 7 after infection of pigs with PRRSV. The double blocking ELISA enabled the distinction at later stages of infection compared to the IPMA, irrespective of the strain involved.

Examination of virus shedding in semen from vaccinated and from previously infected boars after experimental challenge with porcine reproductive and respiratory syndrome virus.

Danish artificial insemination (AI) centres house several boars antibody positive to porcine reproductive and respiratory syndrome virus as well as PRRSV-naive boars which may become acutely infected. The risk of transmission of PRRSV by semen may therefore constitute a serious problem to the Danish pig industry. The use of a vaccination-program may be a way to avoid or reduce the problem. This study evaluates the use of two vaccines: One live, attenuated vaccine and one inactivated vaccine. A pronounced reduction in viremia and shedding of virus in semen was demonstrated by use of the live vaccine compared to the non-vaccinated control animals. In contrast, no changes in onset, level and duration of viremia and shedding of virus in semen were observed using the inactivated vaccine. Neither viremia nor seminal shedding of virus was detected in previously PRRSV-infected, PRRSV-antibody positive boars after challenge with a Danish field strain of PRRSV.

Detection of antibodies against porcine parvovirus nonstructural protein NS1 may distinguish between vaccinated and infected pigs.

The humoral antibody response against the nonstructural protein NS1 and the structural protein VP2 of porcine parvovirus (PPV) was evaluated by immuno-peroxidase test (IPT) and enzyme linked immuno sorbent assay (ELISA) using recombinant PPV antigens. The coding sequence for NS1 and VP2 was inserted into the baculovirus. Autographa californica nuclear polyhedrosis virus (AcNPV) genome resulting in two recombinant baculoviruses AcNPV-NS1 and AcNPV-VP2, respectively. Sf9 cells (Spodoptora frugidiperda) inoculated with AcNPV-NS1 producing recombinant nonstructural protein (rNS1) and AcNPV-VP2 producing recombinant virion protein (rVP2) were used in IPT and ELISA to analyse serum antibodies. Pigs vaccinated with an inactivated whole virus vaccine and experimentally infected pigs were studied. Significant titers against rVP2 were obtained in both vaccinated and infected pigs. Specific antibodies against rNS1 could only be detected in infected pigs and NS1 may in this way allow the specific detection of infected animals. Analysis of serum samples collected up to 18 days post infection (p.i.) from four pigs experimentally infected with PPV showed that antibodies against rNS1 and rVP2 could in all cases be detected on day 9 p.i. Two individual pigs were inoculated twice with PPV and the antibody response was followed 89 days after second inoculation. Serum antibodies against both rVP2 and rNS1 could be detected for this period of time.

Inactivation of virus during anaerobic digestion of manure in laboratory scale biogas reactors.

Reduction of porcine parvovirus, bovine enterovirus and faecal enterococci were measured in biogas reactors continuously run on manure and manure supplemented with household waste at 35 degrees C and 55 degrees C and in batch test run at 70 degrees C. The aim of the experiments was to study the sanitation effect of anaerobic digestion and to evaluate the use of faecal enterococci as an indicator of sanitation. Parallel studies on the reduction of virus and faecal enterococci were done in physiological saline solution. Heat inactivation was found to be an important factor in thermophilic biogas plants and the overall dominant factor at 70 degrees C. However, other environmental factors with a substantial virucidal and bactericidal effect were involved in inactivation. The death rates for faecal enterococci were generally higher than for porcine parvovirus and lower than for bovine enterovirus. For faecal enterococci, a logarithmic reduction of 4 (corresponding to the recommended minimum guaranteed retention time) was obtained after 300 hours at 35 degrees C and after 1-2 hours at 55 degrees C. In continuously-fed reactors, a high reduction rate was initially seen for the virus tested, followed by a reduction in the rate. For porcine parvovirus, a minimum guaranteed retention time of 11-12 hours is necessary at 55 degrees C in the initial phase (0-4 hours) and 54 hours hereafter (4-48 h). Correspondingly, for bovine enterovirus a MGRT of 23 hours was necessary at 35 degrees C and < 0.5 hours at 55 degrees C. The data indicate that faecal enterococci measurements give a good indication of inactivation of enterovirus and other more heat sensitive virus, especially under thermophilic conditions. Parvovirus is very suitable for comparative investigations on inactivation in the temperature range of 50-80 degrees C, due to the extreme thermal resistance of this virus. However, in stipulating sanitation demands for biogas reactors it seems more reasonable to use less resistant virus, such as a reovirus or picornavirus, which better represents the pathogenic animal virus.

Studies on manifestations of canine distemper virus infection in an urban dog population.

An upsurge of canine distemper was recognized at the beginning of 1991 in the urban dog population of the Copenhagen area. The outbreak had the characteristics of a virulent morbillivirus introduction in a partly immune population, where the disease primarily was manifested in young individuals. Testing of single serum samples for the presence of canine distemper virus (CDV) IgM antibodies using an IgM ELISA confirmed current and recent CDV infections in an urban dog population, where the use of attenuated CDV vaccines was widespread. In 49 out of 66 sera from clinical cases suspected of canine distemper we detected CDV IgM antibodies, as compared to the detection of viral antigen by indirect immunofluorescence in 27 of 65 specimens of conjunctival cells. The antigenic make-up of isolates from acute and subacute clinical cases was investigated with a panel of 51 monoclonal antibodies directed against CDV and the related phocine distemper virus. The isolates exhibited an homogeneous reaction pattern and shared overall antigenic characteristics of the CDV prototype. The majority of cases were diagnosed among unvaccinated dogs and individuals with unknown or obscure vaccination record. However, severe clinical cases were also diagnosed in vaccinated individuals.

Neonatal herpes policy in The Netherlands. Five years after a consensus conference.

In order to establish whether the recommendations of an in 1987 organized consensus conference about neonatal herpes policy in the Netherlands had been followed, an inquiry was held in January 1992 among gynecologists, pediatricians and microbiologists. Compared with the results of an inquiry that was held five years before, it was found that the incidence of neonatal herpes had not increased in the last ten years (approximately five cases annually or one per 35,000 neonates) despite the lower frequency of caesarean sections (more than 50 sections a year before 1987 and less than 10 sections a year after 1987). It is concluded that the consensus statements not only have been followed, but that they also proved to be sound.

Infection studies with canine distemper virus in harbour seals.

Infection studies in harbour seal (Phoca vitulina) were conducted with the Snyder-Hill strain of canine distemper virus (CDV) that is virulent for dog and mink. The inoculated seals showed clinical symptoms which were to some degree similar to those observed in CDV infections of sensitive species of carnivores. Viral replication in lymphoid cells was followed by an extended period of immunosuppression. The results did not provide conclusive evidence for viral replication in surface epithelia of seals, and accordingly no spread of the infection to contact seals and mink was demonstrated. The pathogenicity of the infection did not increase upon a second viral passage in seal. The serological data showed that CDV-infected seals mounted an early virus specific antibody response. Overall, the results indicated that the harbour seal was not especially sensitive to CDV infection. The differences in the in vivo biological properties of CDV and PDV add to the distinction between these viruses at the genomic and antigenic levels.

Round table on morbilliviruses in marine mammals.

Since 1988 morbilliviruses have been increasingly recognized and held responsible for mass mortality amongst harbour seals (Phoca vitulina) and other seal species. Virus isolations and characterization proved that morbilliviruses from seals in Northwest Europe were genetically distinct from other known members of this group including canine distemper virus (CDV), rinderpest virus, peste des petits ruminants virus and measles virus. An epidemic in Baikal seals in 1987 was apparently caused by a morbillivirus closely related to CDV so that two morbilliviruses have now been identified in two geographically distant seal populations, with only the group of isolates from Northwest Europe forming a new member of the genus morbillivirus: phocid distemper virus (PDV). Because of distemper-like disease, the Baikal seal morbillivirus was tentatively named PDV-2 in spite of its possible identity with CDV. The appearance of morbilliviruses in the Mediterranean Sea causing high mortality amongst dolphins should further increase the research activities on protection strategies for endangered species of marine mammals.

Coronavirus infection in mink (Mustela vison). Serological evidence of infection with a coronavirus related to transmissible gastroenteritis virus and porcine epidemic diarrhea virus.

Antibodies to a transmissible gastroenteritis virus (TGEV)-related coronavirus have been demonstrated in mink sera by indirect immunofluorescence, peroxidase-linked antibody assays and immunoblotting. This is the first serological evidence of a specific coronavirus infection in mink. The putative mink coronavirus (MCV) seems to be widespread in the Danish mink population with a prevalence approaching 100%. Analysis by immunoblotting has shown that MCV is closely related to TGEV by the spike (S), matrix (M) and nucleoprotein (N) polypeptides. Furthermore, antibodies to MCV also cross-reacted with N and M polypeptides of porcine epidemic diarrhea virus (PEDV). Thus MCV may occupy an intermediate position between the TGEV group of coronavirus and PEDV. The possibility that MCV may be associated with syndromes of acute enteritis in preweaning mink is discussed.

Antigenic relationships between field isolates of morbilliviruses from different carnivores.

The antigenic relationships between PDV and isolates of morbilliviruses from carnivores suffering from distemper were investigated. Fourteen isolates, originating from terrestrial carnivores and harbour seals from 1985-1991 from Denmark, Norway, Greenland, and the U.S.A. were reacted in IFA and ELISA with monoclonal antibodies (MAbs) directed against four virion proteins (NP, P, F, and H). The MAbs comprised a newly completed panel of 36 anti-PDV MAbs and 39 previously developed anti-CDV MAbs. The antigenic make-up of the isolates separated them into the CDV prototype group and the PDV prototype group, having the antigenic characteristics of the reference vaccine strains of CDV and the Danish PDV isolate, respectively. The minor antigenic variations within the CDV group contrasted markedly to the differences encountered between the CDV and PDV group. The PDV group included isolates made in 1988 from diseased seals of Danish and Norwegian waters and isolates made in 1989 from distemper outbreaks in Danish mink farms. In contrast, the other distemper isolates investigated, including isolates from 1986 from a corresponding Danish mink farm, revealed the antigenic characteristics of CDV. Our results strongly indicate that PDV was recently transmitted from diseased seals to terrestrial carnivores causing distemper epizootics among farmed mink.

Demonstration of antibodies against bovine leukemia virus (BLV) by blocking ELISA using bovine polyclonal anti-BLV immunoglobulin.

A blocking enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against bovine leukemia virus (BLV) is described. The test is based on the biotin-streptavidin system using unlabelled polyclonal bovine IgG against BLV as catching antibody and biotinylated bovine anti-BLV IgG as detecting antibody. The sensitivity was found to be 50-100 times higher than the agar gel immunodiffusion test, with a specificity of practically 100%. The blocking ELISA proved to be suitable for detection of antibodies against BLV in serum and milk. In 34 paired milk/serum samples, the average ratio of BLV antibody titres was 1:26. So far, more than 700,000 sera have been screened by blocking ELISA for BLV antibodies in the course of the Danish surveillance programme for BLV infection.

The seal death in Danish waters 1988. 2. Virological studies.

Mass abortions and high mortality were observed in harbour seals in Danish waters during 1988. Severe pneumonia and emphysema were typical clinical and post-mortem findings. Virological studies were carried out to identify the cause of the epidemic. Although seal herpesvirus (SeHV) was isolated in 23 of 114 animals this virus was subsequently found not to be the primary cause of the disease. Following the observation of seroconversion against canine distemper virus (CDV) in diseased seals (Osterhaus & Vedder 1988) a CDV-like morbillivirus (phocine distemper virus, PDV) was identified in organs of diseased animals. It is concluded that the epidemic was caused by introduction of PDV into a highly susceptible population presumably free from morbillivirus infection. The origin of PDV remains unknown but evidence of prior morbillivirus infection has been found in arctic and antarctic seal populations.

Immunological relationships between phocid and canine distemper virus studied with monoclonal antibodies.

The immunological relationships between distemper viruses, isolated from a seal and mink in Denmark and from a dog in Greenland, were investigated with 39 previously developed monoclonal antibodies (MAbs) directed against four major structural proteins of canine distemper virus (CDV). They were also investigated with 16 newly developed MAbs directed against the fusion (F) and large glycoprotein (named H in analogy with measles virus) of phocid distemper virus (PDV) isolated from a harbour seal (Phoca vitulina). These MAbs were reacted with the three different isolated viruses and with the LEC strain of measles virus, in ELISA and immunofluorescence tests. In addition, immunoprecipitation tests were carried out with some of the cross-reacting antibodies. All 55 MAbs reacted identically with distemper virus isolated from seals or mink. When the MAbs produced against CDV were tested, 37 of 39 antibodies reacted with a virus isolated from a sled dog diseased in an outbreak of distemper in Greenland prior to the epizootic among seals in the North Sea. Of the 39 antibodies, 25 reacted with PDV and distemper virus isolated from mink. Of these antibodies, only three of the nine antibodies directed against the H protein of CDV cross-reacted with PDV and distemper virus from mink. Eleven MAbs, reacting with six epitopes of the H protein of PDV, were produced. All 11 antibodies reacted with distemper virus from mink, two of the antibodies reacted with CDV and none reacted with measles virus. All five antibodies reacting with three different epitopes of the F protein of PDV reacted with distemper virus from mink and CDV. Of these five antibodies three, directed against two epitopes, reacted with measles virus. Of the two envelope proteins, the H protein shows pronounced immunological differences between PDV and CDV. In contrast, immunologically the F protein appears to be well conserved among morbilliviruses. It is concluded that the virus causing the epizootic in seals in the North Sea in 1988 may have infected mink on land, or, alternatively, the virus in the sea may have originated from virus-infected mink.