Assessment of the effectiveness of inactivated influenza vaccines for adults

In 9 controlled epidemiological observations (1977-1984) the effectiveness of modern Soviet whole-virion vaccines was studied in organized groups of adults and at industrial enterprises. During the epidemic outbreaks of influenza of different etiology and intensity morbidity rate in influenza and acute respiratory diseases was shown to decrease 1.1-2.2 times among the vaccinees, depending on the correspondence of epidemic and vaccine influenza strains. The absence of influenza virus B in inactivated influenza vaccines was the reason for their low effectiveness during influenza outbreaks of mixed etiology B + A (H1N1).     

The effectiveness of using the Vaxigrip vaccine from the firm of Pasteur Mérieux Connaught for influenza prevention in organized groups of adults

The results of the study of the effectiveness of using vaccine Vaxigrip for the prophylaxis of influenza in organized groups of adults are presented. The vaccine was found to have high epidemiological effectiveness (the epidemiological index was 2.6), moderate reactogenicity and pronounced immunological activity (the protection level was 89.0-100.0%). The vaccine may be recommended for the prophylaxis of influenza among adults.     

Assessment of the prophylactic effectiveness of an inactivated influenza vaccine by immunizing schoolchildren in the springtime

To evaluate the prophylactic effectiveness of influenza inactivated chromatographic vaccine, limited epidemiological observations were made on school children aged 11-14 years in Leningrad, in the autumn of 1981 and the spring of 1982. For immunization, made in a single administration, the vaccine composed of A (H3N2) + +A (H1N1) and containing 3.0-3.4 micrograms of hemagglutinin of each component per 0.2 ml of the preparation was used. Altogether 6928 schoolchildren were under observation; of these, 3686 children were immunized and 3242 children received placebo. The results of questioning and the analysis of morbidity rate among the schoolchildren, both immunized and receiving placebo, showed the safety and low reactogenicity of the vaccine irrespective of the time of the immunization campaign. The immunogenic potency of the preparation, as indicated by all observation results, proved to be higher in spring, than in autumn. The data thus obtained indicate that children immunized in spring were better protected and retained a higher level of protection within 12 months after immunization. The shift of the time of the immunization campaign from autumn to spring increased the immune layer in the groups of children by 16.5%. In 10 months after spring immunization the morbidity rate in influenza and acute respiratory diseases among the vaccinees was found to decrease 1.7 times.     

The evaluation of the reactogenicity, harmlessness and prophylactic efficacy of Grippol trivalent polymer-subunit influenza vaccine administered to schoolchildren

Vaccine "Grippol"--has been developed at the State Research Center--Institute of Immunology. The preparation belongs to new generation vaccines and is a trivalent polymer-subunit vaccine containing the sterile conjugate of influenza virus surface proteins, types A and B, bound with copolymer polyoxidonium. The administration of "Grippol" to children of school age (6-18 years) demonstrated low reactogenicity of the vaccine, its safety and sufficient prophylactic effectiveness. During observations on total morbidity (with the exception of influenza and acute respiratory diseases) no side effects produced by "Grippol" were registered. At the same time the fact that the morbidity rate of upper respiratory tract disease in the group of children immunized with the vaccine decreased in comparison with the control group (by 2.4 times) cannot be disregarded.     

Live enteroviral vaccines for the emergency nonspecific prevention of mass respiratory diseases during fall-winter epidemics of influenza and acute respiratory diseases]

The results of the 3-year controlled trials of a new method of nonspecific urgent prophylaxis of influenza and acute respiratory diseases (ADR) by immunization of healthy adults with standard live enterovirus oral vaccines, introduced in 2-3 administrations at intervals of 7-10 days, at the initial stages of autumn and winter epidemics are presented. Observations, carried out in three republics, covered more than 150,000 persons immunized with enterovirus interferonogenic vaccines. A considerable decrease in morbidity rate among the vaccinees was achieved (on the average, by 3.2 times) in comparison to that among nonimmunized subjects. The method of nonspecific prophylaxis with live enterovirus interferonogenic vaccines is recommended during outbreaks of diseases induced simultaneously by several causative agents of influenza and ARD, as well as by pathogenic enterovirus strains.     

Antigenic anachronism of the influenza A(H2N2) viruses in Leningrad in 1980. I. The epidemiological and serological characteristics of the influenzal infection caused by A/Leningrad/80 (H2N2) viruses

In April-May 1980 a number of unrelated outbreaks of influenza-like diseases were registered in Leningrad in an infant home (50 out of 68 children under observation, aged 3 months to 2 years, were affected) and among the pupils of a boarding school (13 out of 50 adolescents under observation, aged 15-17 years, were affected). 5 strains of influenza A virus were isolated from 3 sick children and 1 clinically healthy child. A similar virus was isolated from a sick adolescent in a boarding school, as well as from a female patient aged 24 years at a domiciliary focus of infection (a sporadic case). In the subsequent laboratory investigation all these 7 strains were identified as viruses A/H2N2. Isolated cases of seroconversion to hemagglutinin H2 were definitely registered in 6 patients during February--May 1980. In 3 cases, including the 24-year old female patient with an acute respiratory disease, seroconversion to hemagglutinin H2 was observed in combination with the release of influenza viruses A/H2N2 from these patients. 2 influenza virus strains with this antigenic characteristic were isolated from a young female patient at an interval of 3 days. Among the patients admitted to the clinics of the Research Institute of Influenza in Leningrad on account of acute respiratory diseases isolated cases of diagnostically significant seroconversion to hemagglutinin H2 constituted 3.5% among children and 4.5% among adults. The study of the level of antihemagglutinins in the population revealed that in 1980 persons aged 18-50 years showed a high level of antihemagglutinins.(ABSTRACT TRUNCATED AT 250 WORDS)     

儿童乙型流感病毒感染特点及防治的研究进展

乙型流感病毒是引起流行性感冒(简称流感)发生和流行的主要病原体之一,近年来流感高发的季节感染率呈上升趋势,儿童是乙型流感病毒感染的易感、高危群体。乙型流感病毒虽然抗原变异性较弱,但仍可引起暴发流行,严重威胁患儿的健康,因此对于儿童乙型流感病毒感染的防治至关重要。本文综合近年来国内外相关文献,从流行病学特征、临床表现、实验室检查、乙型流感病毒感染的药物治疗、免疫疗法等角度出发对乙型流感病毒感染特点及治疗进展予以综述,对乙型流感病毒进行长期有效的监测,了解儿童乙型流感病毒的感染特点,为儿童乙型流感的预防及临床诊断与防治提供理论参考。     

Role of genetic factors in the epidemic process in respiratory viral infections

Observations carried out during 1973-1979 indicate that persons, who are frequently ill, determine the incidence of influenza and acute respiratory diseases among various groups of adult population at all epidemic periods. In constantly observed groups of different ages such persons were the source of 60-85% of the outbreaks of acute respiratory diseases. The correlation between genotypic blood markers (the ABO and HLA systems) and susceptibility to respiratory viruses has been established.     

Efectividad de la vacuna antigripal en la prevención de la gripe en personas mayores de 65 años

IntroductionInfluenza is one of the diseases with the greatest epidemiological impact and of maximum relevance in the management of health services. The flu vaccine can have great variability each season, so our objective was to find out the effectiveness of the flu vaccine for the 2017/2018 season for the prevention of severe cases of flu in people over 65 years of age in a 385-bed acute general hospital.Material and methodStudy of cases and controls. All hospitalized patients with laboratory-confirmed influenza older than 65 years during the 2017/2018 season were included. Those who met the criteria for a severe case of influenza were considered cases. Those who did not meet the severity criteria were considered controls. Factors associated with the development of severe influenza were calculated.ResultsThe median age was 68 years (SD 91.87). The attack rate was 0.23 per hundred inhabitants and the vaccine effectiveness was 38%. The vaccinated and unvaccinated groups were different in terms of age (p < 0.0481). Vaccination status against severe influenza was found to be an independent protective factor (OR = 0.840; 0.746-0.913).ConclusionsThe effectiveness of influenza vaccination provided greater protection against infection and reduced the severity of influenza in older hospitalized patients. These findings should be taken into account to improve vaccination strategies and achieve better vaccination coverage in the population at risk.     

Serological and epidemiological characteristics of acute pneumonias caused by Mycoplasma pneumoniae in Belgorod

The etiology of the outbreaks of acute pneumonia in Belgorod was established and their epidemiological features were studied. The mycoplasmal etiology of all cases of acute pneumonia in children and adults, appearing alongside acute respiratory infections resulting from the preceding outbreaks caused by influenza viruses A/Prague/, B/Leningrad/369/75, and all types of parainfluenza viruses, was shown. The droplet mechanism of the transfer of infection was established, which was confirmed by the severity of the outbreak and a high rate of infection of the medical staff at hospitals for children and adults, where patients with mycoplasma-induced pneumonia were treated.     

流感病毒疫苗佐剂研究现状

流行性感冒是一类由流感病毒引起的急性呼吸道传染病。其发病率高、传染性强,因此作为最佳预防手段的流感疫苗关注度日益提升。而佐剂的使用可提升流感疫苗的效果并减少相应抗原的使用量,因此成为研究热点。就应用于流感疫苗中佐剂的研究现状做一综述。     

Significance of Legionella pneumophila in human respiratory pathology

The etiological structure of acute pneumonia and acute respiratory diseases was studied with a view to establishing the proportion of L. pneumophila among other causative agents of such diseases. A total of 299 patients were examined over time. The etiological diagnosis based on the data of serological examination was made in 70.6% of the patients with acute pneumonia and in 65% of the patients with acute respiratory viral infections and influenza. In the etiology of pneumonia, the leading role was found to belong to influenza A (H3N2) and B viruses, as well as to adenovirus, while in the etiology of acute respiratory viral infections and influenza, to influenza B virus, adenovirus and Mycoplasma pneumoniae. The importance of L. pneumophila in the etiology of acute pneumonia and acute respiratory diseases was shown. The proportion of L. pneumophila proved to be, on the average, 9.9% in acute pneumonia and 9.8% in acute respiratory diseases. L. pneumophila occurred most frequently in mixed infections in combination with adenovirus and influenza B virus. Diseases of Legionella etiology were found to have a seasonal character, occurring mostly in winter and spring.     

Prevention of influenza in the general population

Background

Although all jurisdictions in Canada offer annual influenza immunization to people at high risk of complications, only Ontario has provided universal annual immunization of healthy adults and children. Use of chemotherapy (amantidine, neuraminidase inhibitors) to prevent influenza varies among provinces. We sought to systematically review the evidence for the prevention of influenza infection in the general population.

Methods

The interventions reviewed were influenza vaccination and prophylactic use of neuraminidase inhibitors. The health outcomes of interest were rates of laboratory-confirmed influenza infection, clinical definitions of influenza-like illness and work absenteeism. MEDLINE and Cochrane databases were searched for relevant articles published between 1966 and March 2003. Only randomized controlled trials (RCTs) were selected. Evidence was appraised using the methodology of the Canadian Task Force on Preventive Health Care.

Results

Eighteen trials involving more than 33 000 healthy adults were identified that met the inclusion criteria; of these, 15 showed that influenza vaccination with either live-attenuated and inactivated vaccines was efficacious. Eleven trials were considered to be of “good” quality, and 7 were considered to be of “fair” quality. The relative risk reduction (RRR) associated with influenza immunization in adults ranged from 0% to 91%. Fifteen RCTs involving more than 45 000 healthy children aged 6 months to 19 years were identified, of which 9 were considered to contain “good” evidence and 6 “fair” evidence. Results from 12 of these trials showed protection against influenza. The RRR ranged from 0% to 93%. There were 6 RCTs of “good” quality showing that neuraminidase inhibitors are effective in preventing influenza infection. Side effects from both influenza vaccination and neuraminidase inhibitor administration were mild.

Interpretation

There are numerous RCTs of good quality in large populations that have consistently shown that influenza vaccination, using inactivated or live-attenuated vaccines, is moderately effective in preventing influenza in the general population (healthy adults and children over 6 months of age). There is good evidence that neuraminidase inhibitor prophylaxis in contacts given within 36 to 48 hours of symptom onset of the household index case is effective; appropriate use of this prevention method requires access to rapid diagnostic methods. Decisions about introduction of routine immunization programs must take into account the cost and cost-effectiveness of a universal program and the burden of illness associated with influenza in each jurisdiction.Influenza virus causes yearly epidemics of respiratory illness of varying severity worldwide in people of all ages, and it may be the most important cause of medically attended acute respiratory illness.¹ In Canada influenza and pneumonia are the leading cause of death from infection and the sixth cause of death overall.² Rates of complications and death from influenza are high among adults over 65 years of age and people with cardiac or pulmonary disease or chronic medical conditions, and annual influenza immunization in this population is associated with lower frequency of hospital admissions because of respiratory disease, congestive heart failure and death from any cause.^3,4 Previously healthy young children are increasingly recognized as having hospital admission rates comparable to those among elderly people during influenza epidemics⁵ and up to 12-fold greater than rates among older children.⁶ Because influenza occurs yearly and because re-infections occur throughout the lifespan and affect up to 20% of the population each year, considerable attention has been directed to the prevention of influenza in healthy people. Although annual immunization programs are routinely offered to high-risk groups, only the province of Ontario routinely offers influenza immunization to healthy adults and children.We performed a systematic review of the literature to answer the following question: how effective are the influenza vaccine and prophylactic neuraminidase inhibitor antiviral agents for the prevention of influenza in healthy adults and children?     

Experience of using bacterial lysate IRS 19 for the prophylaxis of the diseases of respiratory organs in organized groups

To solve the problem of unfavorable sanitary and epidemiological situation in diseases of respiratory organs in one of the organized groups in the Moscow region, a preparation prepared from a group of curative vaccines, IRS 19, was used. For controlling the effectiveness of its prophylactic action two groups of 250 persons were formed. As a result, morbidity rate in respiratory diseases decreased 2.5-3 times. In 1.5 months after the use of the preparation was started the coefficient of protection against the whole group of diseases of respiratory organs was 70%.     

Use of prodigiozan for preventing acute respiratory viral diseases in a children's collective]

The epidemiological efficacy of 0.02 per cent solution of prodigiosan, a bacterial polysaccharide was used for the treatment of children in an area with acute respiratory infections, such as influenza and parainfluenza. The drug was administered intranasally by means of a dosing sprayer in the amounts of 0.2 ml once in 4 days for 4 months. Among the children treated with prodigiosan the rate of the acute respiratory viral infections was 2 times lower and the average duration of the disease was 2.4 times lower as compared to the control group. After 4 months of the drug use the average value of the "skin autoflora" test was much lower than that in the control group which testified to an increase in the non-specific immunobiological reactivity of the children under the effect of prodigiosan.     

Call to action: cardiologists should promote influenza vaccination

The COVID-19 pandemic has spurred clinical and scientific interest in the cardiology community because of the significantly enhanced vulnerability of patients with underlying cardiac diseases. COVID-19 vaccination is therefore of vital importance to the patients we see in our clinics and hospitals every day and should be promoted by the medical community, especially cardiologists. In view of vaccine-preventable diseases, the association between influenza and cardiovascular complications has been widely investigated. Several studies have found a substantially elevated risk of hospital admission for acute myocardial infarction in the first 7 days after laboratory-confirmed influenza, with incidence ratios ranging from 6.05–8.89. The effectiveness of the influenza vaccine to protect against acute myocardial infarction is about 29%. This effectiveness is comparable to or even better than that of existing secondary preventive therapies, such as statins (prevention rate approximately 36%), antihypertensives (prevention rate approximately 15–18%), and smoking cessation (prevention rate approximately 26%). As the influenza season is rapidly approaching, this Point of View article serves as a call to action: Cardiologists should promote influenza vaccination and actively advice their patients to get the seasonal influenza vaccination.     

Epidemiological and economic effectiveness of immunization of adult and children against influenza and acute respiratory viral infections with the vaccine Grippol

Materials on the characterization of the vaccine Grippol, indications for its use and the results of mass use are presented. Analysis of the morbidity level in influenza and acute respiratory viral infections (ARVI) among the vaccinated persons are indicative of considerably decreased level. The coefficient of the epidemiological effectiveness of Grippol in the immunization of children has proved to be 75-95%. The conclusion has been made that the vaccine Grippol is sufficiently effective and safe for use by Russian public health service.     

Effectiveness of peroral and intranasal immunization of school children with live allantoic influenza vaccine- and comparative study.

A comparative study of two preparations of allantoic live influenza vaccine, one for intranasal and the other for peroral immunization of children of school age, was peformed under conditions of a blind epidemiological trial. Previously obtained data on the safety and high immunogenicity of the intranasal vaccine variant, prepared from extremely attenuated cold-adapted strains, were confirmed. The peroral administration of the live influenza vaccine, in use in the USSR for active immunization of the adult population, also stimulated influenza immunity without producing postvaccinal reactions. Peroral and intranasal immunization with the above variants of live allantoic influenza vaccine markedly lowered in the frequency of influenza disease during an influenza epidemic, the mean index of effectiveness being equal to a factor of 2. Evidence of prospectiveness of influenza prophylaxis among school children was obtained.     

Results of introducing a comprehensive system of influenza control in the population of Severodvinsk

A complex differentiated system of influenza control, based on scientific principles, was introduced into practice during 1976-1980 in Severodvinsk. The main component of this system was the mass prophylactic immunization of the population of the city, including children and elderly persons, with live and inactivated vaccines manufactured in the USSR. At the period of influenza epidemics remantadin was used for the urgent prophylaxis and treatment of influenza. As a result, influenza morbidity in Severodvinsk was reduced 1.5-2 times in comparison with that in the neighboring control cities. The cases of pneumonia and bronchitis, the most severe postinfluenza complications, decreased in number 1.8 and 1.4 times, respectively. The proportion of influenza A in the structure of acute respiratory diseases decreased by one-half. These results demonstrate the effectiveness of the prophylactic and therapeutic measures carried out in the city.     

New approaches to quantifying the spread of infection

Recent major disease outbreaks, such as severe acute respiratory syndrome and foot-and-mouth disease in the UK, coupled with fears of emergence of human-to-human transmissible variants of avian influenza, have highlighted the importance of accurate quantification of disease threat when relatively few cases have occurred. Traditional approaches to mathematical modelling of infectious diseases deal most effectively with large outbreaks in large populations. The desire to elucidate the highly variable dynamics of disease spread amongst small numbers of individuals has fuelled the development of models that depend more directly on surveillance and contact-tracing data. This signals a move towards a closer interplay between epidemiological modelling, surveillance and disease-management strategies.