Reduced reaction frequencies with repeated inactivated or live-attenuated influenza vaccination

Data collected as part of a multi-year trial examining the efficacies of inactivated and live-attenuated influenza vaccines were used to evaluate the reported occurrence of post-vaccination reactions. Two cohorts were defined: (1) individuals who received the same vaccine over two consecutive years, and (2) individuals who first enrolled in year 2 of the study and received vaccine only in that year. For both vaccines there were significantly fewer reactions reported in year 2 in those subjects who were vaccinated both years. Declines were demonstrated when comparing year 1 and 2 reaction frequencies in subjects vaccinated both years, and differences were seen when comparing year 2 reaction frequencies in subjects vaccinated both years with those first vaccinated in year 2. Reaction reporting peaked on post-vaccination days 0 and 1 following receipt of the inactivated vaccine, and on day 2 following receipt of the live-attenuated vaccine.     

Antibiotic prescribing during an outbreak of meningococcal disease.

During a prolonged outbreak of meningococcal disease caused by serogroup B serotype 15 sulphonamide-resistant strains in one British health district, there was considerable variation in attack rates by town. General practitioner (GP) antibiotic prescribing rates were compared in high and low incidence towns. The only significant difference found was that erythromycin prescribing was more frequent in the high incidence towns (rate ratio 4.0, 95% CI 3.2-4.8, in March 1987 and 3.0, 95% CI 2.4-3.7, in November 1987). This was probably due to increased GP consultation rates for upper respiratory tract infection (URTI), but higher erythromycin usage may have increased meningococcal acquisition rates or susceptibility to meningococcal disease. Antibiotic prescribing rates should be further investigated in defined areas of high and low incidence of meningococcal disease.     

The field effectiveness of routine and emergency vaccination with an inactivated vaccine against foot and mouth disease

High potency, inactivated foot and mouth disease (FMD) vaccines may be used in non endemic countries for emergency vaccination during outbreaks in order to prevent virus spread. In endemic countries either standard or high potency vaccines are used for routine vaccination. Despite their wide use there is a shortage of data on the field effectiveness of inactivated FMD vaccines. Epidemics of FMD caused by viruses of serotype O occur frequently in Israel, where a high potency (≥6PD₅₀) vaccine is used for both routine and emergency vaccination. We investigated an outbreak of FMD caused by a virus of serotype O, which took place during 2011 in a feedlot and an adjacent dairy herd. Post outbreak testing of antibodies against non-structural protein demonstrated that infection occurred in 96% of the calves that received two doses of vaccine at least three months prior to the outbreak and more than 50% showed clinical signs consistent with FMD. Replacement heifers that had been vaccinated 3–5 times with the last vaccination administered 7 months prior to the outbreak were all infected and 18% showed clinical signs. Testing of cattle sera of the same vaccination status as the affected cattle demonstrated low neutralizing antibody (NA) titers against the field virus strain and an r₁ value of 0.37 compared to the vaccine strain. In contrast, cattle vaccinated only once but up to two weeks before the outbreak, were almost all protected from clinical disease and to a lesser extent, protected from FMD virus infection, despite low NA titers. We conclude that emergency vaccination was highly effective due to a mechanism not associated with NA, whereas routine vaccination with the same vaccine formulation provided only limited protection due to poor longevity of the elicited immunity and low matching with the field strain (despite an r₁ higher than 0.3).     

Influenza vaccination perception and coverage among patients with malignant disease

BackgroundPatients with malignancies are at increased risk of serious influenza related complications with higher rates of hospitalization and mortality than healthy cohorts. Although annual vaccination against influenza infection is recommended, vaccination rates among cancer patients are apparently low. The reasons for the low compliance to influenza vaccine and the influenza vaccination rate among Austrian cancer patients have not been studied in detail yet.Patients and methodsFrom July 1, 2013 to October 31, 2013, 444 patients treated in the outpatient departments of the Clinical Division of Oncology and the Clinical Division of Haematology and Haemostaseology of the General Hospital Vienna participated in a survey on different aspects of influenza vaccination.ResultsIn total, only 80 out of 444 patients (18%) had received influenza vaccination in the previous year. The influenza vaccination rate was higher amongst patients with haematological malignancies (22%) compared to patients with solid tumours (13%). Higher age was significantly associated with a higher probability for being vaccinated. Collecting information about influenza vaccination primarily from media or the internet was not significantly associated with influenza vaccination status. Information through a medical consultation or a recommendation by the attending physician resulted in significant higher influenza vaccination coverage rates. Only 199 out of the 444 patients (44.8%) were informed by a physician about influenza vaccination and only 18 out of 337 patients (5.3%) with a diagnosis of a malignant disease were informed by their treating oncologist. The main reasons for influenza vaccination denial were concerns about interaction with the malignant disease and potential side-effects.ConclusionInformation about influenza vaccination during a medical consultation and a clear recommendation by the attending physician are highly predictive for acceptance of influenza vaccination. Increased awareness among physicians, especially oncologists is of utmost importance to effectively improve IVR in patients with malignant disease.     

Nosocomial Influenza outbreak in an intensive-care unit

Objective – The authors investigated a nosocomial outbreak of pneumonia to determine the etiological diagnosis, to evaluate the transmission route, the modalities of prevention, and the cost.Methods – All patients and staff members present in this acute-care unit had nasal wash, pharyngeal sampling and serological testing for detection of pneumonia agents. Epidemiological variables studied included influenza like illness, underlying disease and Influenza vaccine. The estimation of cost included excess days hospitalization, number of laboratory tests, medical imagery and treatment of patients, and sick leave days for staff category.Results – Investigation determined that it was an Influenza A outbreak, with nosocomial acquisition. Nine of 23 hospitalized patients (39%) and 5/22 (23%) staff members had Influenza A infection. Influenza vaccine was protective since the 11% (2/18) attack rate among the vaccinated persons of was significantly lower (p=0.03) than that of no-vaccinated persons [41% (11/27)]. The influenza vaccine efficacy was 73%. The main over cost associated to this outbreak was due to the excess days hospitalization and was estimated to be of 222 235 Francs.Conclusion – Vaccination of health care workers is essential to prevent nosocomial Influenza spread and may represent important money savings.     

Influenza vaccination. Shot down

The government's policy to give everyone over 65 a flu vaccination this winter lacks detail on implementation. A study of vaccination in nine general practices in England last year suggests much greater organisation is required to achieve high take-up rates. Although all practices were computerised and had an age-sex register, they did not use these to plan their vaccination programmes. On its own, computerisation is not a sufficient basis for organising a comprehensive programme. Most practices relied on patients presenting themselves for vaccination.     

Influenza: an emerging disease.

Because all known influenza A subtypes exist in the aquatic bird reservoir, influenza is not an eradicable disease; prevention and control are the only realistic goals. If people, pigs, and aquatic birds are the principal variables associated with interspecies transfer of influenza virus and the emergence of new human pandemic strains, influenza surveillance in these species is indicated. Live-bird markets housing a wide variety of avian species together (chickens, ducks, geese, pigeon, turkeys, pheasants, guinea fowl), occasionally with pigs, for sale directly to the public provide outstanding conditions for genetic mixing and spreading of influenza viruses; therefore, these birds should be monitored for influenza viruses. Moreover, if pigs are the mixing vessel for influenza viruses, surveillance in this population may also provide an early warning system for humans.     

Effectiveness and safety of immunization with live-attenuated and inactivated vaccines for pediatric liver transplantation recipients

BackgroundLiver transplantation recipients are at high risk for severe complications due to infections because of being treated with immunosuppressive drugs that affect the immune system. Vaccination for liver transplantation candidates is generally recommended before surgery, but the opportunities for vaccination prior to transplantation in pediatric candidates are often limited by severe disease conditions.MethodsThe participants in this study comprised 39 pediatric recipients of living donor liver transplantation performed between 2005 and 2013. Criteria for administering live-attenuated (measles, rubella, mumps, and varicella) and inactivated (hepatitis B, pertussis, and Japanese encephalitis) vaccines were as follows: (1) >1 year after transplantation; (2) no use of systemic steroids to treat acute rejection within the last 6 months; (3) serum trough concentration of tacrolimus <5 ng/mL; (4) no severe immunosuppression according to blood examinations; and (5) provision of written informed consent. Median age at transplantation was 17 months, and median period from transplantation to the beginning of immunization was 18 months.ResultsSeroprotection rates for measles, rubella, mumps, varicella, hepatitis B, pertussis, and Japanese encephalitis after post-transplant immunization were 44% (11/25), 70% (19/27), 48% (12/25), 32% (6/19), 83% (19/23), 87% (13/15), and 88% (7/8), respectively. Seroprotection rates for measles, rubella, mumps, and varicella after second vaccination for recipients with primary vaccine failure after first vaccination were 100% (8/8), 50% (1/2), 71% (5/7), and 50% (5/10), respectively. While four recipients contracted mumps and eight contracted varicella before immunization, one recipient developed varicella after immunization. No serious systemic adverse events were observed in vaccinated recipients.ConclusionsSeroprotection rates for measles, mumps, and varicella appeared low in children after the first post-transplantation vaccination. Immunizations with four live-attenuated and three inactivated vaccines were safe and effective for pediatric liver transplantation recipients who were not severely immunosuppressed.     

Experience of hepatitis A vaccination during an outbreak in a nursery school of Tuscany,Italy.

An outbreak of hepatitis A started in late October 1996 in a nursery school in Tuscany, Italy. A programme of hepatitis A vaccination without the use of immunoglobulin started at the beginning of December 1996 and included 33 children, 21 household contacts and 6 adults working in the school. Overall, 11 cases occurred in children attending the school (attack rate 27%) and 10 among their household contacts (attack rate 9 %). The latter also included parents, and, in two cases, grandmothers. The data indicate that susceptibility to HAV has increased over recent decades in central Italy. Past and recent experience shows that the usual duration of hepatitis A epidemics in the absence of immune prophylaxis is longer than that described here. The use of hepatitis A vaccine probably contributed to the early extinction of the outbreak, because no further cases were notified in the area after 7 February 1997.     

Cost-effectiveness of live-attenuated influenza vaccination among school-age children

The current pediatric vaccination program in England and Wales administers Live-Attenuated Influenza Vaccine (LAIV) to children ages 2–16 years old. Annual administration of LAIV to this age group is costly and poses substantial logistical issues. This study aims to evaluate the cost-effectiveness of prioritizing vaccination to age groups within the 2–16 year old age range to mitigate the operational and resource challenges of the current strategy. We performed economic evaluations comparing the influenza vaccination program from 1995–2013 to seven alternative strategies targeted at low risk individuals along the school age divisions Preschool (2–4 years old), Primary school (5–11 years old), and Secondary school (12–16 years old). These extensions are evaluated incrementally on the status quo scenario (vaccinating subgroups at high risk of influenza-related complications and individuals 65+ years old). Impact of vaccination was assessed using a transmission model from a previously published study and updated with new data. At all levels of coverage, all strategies had a 100% probability of being cost-effective at the current National Health Service threshold, £20,000/QALY gained. The incremental analysis demonstrated vaccinating Primary School children was the most cost-efficient strategy compared incrementally against others with an Incremental Cost-Effectiveness Ratio of £639 spent per QALY gained (Net Benefit: 404 M£ [155, 795]). When coverage was varied between 30%, 55%, and 70% strategies which included Primary school children had a higher probability of being cost-effective at lower willingness-to-pay levels. Although children were the vaccine target the majority of QALY gains occurred in the 25–44 years old and 65+ age groups. Influenza strain A/H3N2 incurred the greatest costs and QALYs lost regardless of which strategy was used. Improvement could be made to the current LAIV pediatric vaccination strategy by eliminating vaccination of 2–4 year olds and focusing on school-based delivery to Primary and Secondary school children in tandem.     

Mass vaccination campaign following community outbreak of meningococcal disease

During December 12-29, 1998, seven patients ages 2-18 years were diagnosed with serogroup C meningococcal disease in two neighboring Florida towns with 33,000 residents. We evaluated a mass vaccination campaign implemented to control the outbreak. We maintained vaccination logs and recorded the resources used in the campaign that targeted 2- to 22-year-old residents of the two towns. A total of 13,148 persons received the vaccinations in 3 days. Vaccination coverage in the target population was estimated to be 86% to 99%. Five additional cases of serogroup C meningococcal disease occurred in the community during the year after the campaign began, four in patients who had not received the vaccine. The cost of control efforts was approximately $370,000. Although cases continued to occur, the vaccination campaign appeared to control the outbreak. Rapid implementation, a targeted approach, and high coverage were important to the campaign's success.     

Prior DNA vaccination does not interfere with the live-attenuated measles vaccine

The currently used live-attenuated measles vaccine is very effective although maternal antibody prevents its administration prior to 6 months of age. We are investigating the ability of a DNA vaccine encoding the measles viral hemagglutinin, fusion and nucleoprotein to protect newborn infants from measles. Here, we show that a measles DNA vaccine protects juvenile macaques from pathogenic measles virus challenge and that macaques primed and boosted with this DNA vaccine have anemnestic antibody and cell-mediated responses after vaccination with a live-attenuated canine distemper-measles vaccine. Therefore, this DNA vaccine administered to newborn infants may not hinder the subsequent use of live-attenuated measles vaccine.     

Influenza vaccination—acceptance in an industrial population

Smith, J. W. G., Pollard, R., Fletcher, W. B., Barker, R., and Lewis, J. R. (1974).British Journal of Industrial Medicine,31, 292-297. Influenza vaccination—acceptance in an industrial population. Influenza vaccination was offered in a pharmaceutical factory of approximately 6 000 employees in December 1971 and again in December 1972. The rate of acceptance of vaccination was 42% in 1971 but fell to only 27% in 1972, and was highest among middle-aged married women and lowest among young men. Only 57% of employees who were vaccinated in 1971 and were still employed in 1972 accepted vaccination on the second occasion. Re-vaccination was commoner in staff (64%) than in works employees (52%) in all age and sex categories, and was commoner in older than in younger employees. Only 6% of employees who did not accept vaccination in 1971 accepted the vaccine in 1972. Among new employees who were not in the factory in December 1971 the acceptance rate was 21% in 1972.

Between January 1971 and 1972 vaccinated employees left the factory less commonly (15%) than those who had not accepted vaccination (22%). Loss of working time in April to September 1972, i.e., when it is unlikely that influenza would have influenced the returns, was 21% higher among non-vaccinated employees than in vaccinated employees, the difference being due to certified illness of more than three days' duration.

The benefit to be derived from offering influenza vaccination to a factory or office population will depend, among other factors, on the proportion of employees who accept the offer and on the characteristics of this volunteers group. The low take-up rate (27%) observed in the second year suggests that annual influenza vaccination is unlikely at the present time to have a marked effect on absence during outbreak periods. In comparison with the non-volunteers in the present study, the volunteers included a higher proportion of married women, older persons, and staff employees and were less inclined to leave employment, and lost less working time from certificated sickness absence. The value of offering vaccine may therefore be greatest in an established office employing a high proportion of older women. The differences between the volunteers and non-volunteers, particularly the better sickness absence record of the former, indicates that the effect of influenza vaccination cannot reliably be assessed only from a comparison of absence returns between vaccinated and unvaccinated employees.