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SummaryBackgroundThis study evaluated the safety and immunogenicity of an AS03-adjuvanted SARS-CoV-2 recombinant protein candidate vaccine, CoV2 preS dTM.MethodsThis Phase 2, modified double-blind, parallel-group study (NCT04762680) was conducted in adults, including those at increased risk of severe COVID-19. Participants were randomised 1:1:1, stratified by age (18–59/≥60 years), rapid serodiagnostic test (positive/negative) and high-risk medical conditions (yes/no), to receive two injections (day [D]1 and D22) of 5μg, 10μg or 15μg of CoV2 preS dTM antigen with fixed AS03 content. Interim safety and reactogenicity results (to D43) and neutralising antibodies (NAbs) against the D614G variant are presented (primary objectives).FindingsOf 722 participants enrolled and randomised between 24 February and 8 March 2021, 721 received ≥1 injections (5μg, n=240; 10μg, n=239; 15μg, n=242). Four participants reported unsolicited immediate adverse events (AEs), two were vaccine-related (investigator assessment). Five participants reported seven vaccine-related medically-attended AEs. No vaccine-related serious AEs and no AEs of special interest were reported. Solicited reactions (local and systemic) were reported at similar frequencies between study groups; these were mostly mild to moderate and transient, with higher frequency and intensity post-injection 2 than post-injection 1. In SARS-CoV-2 naïve participants at D36, 96·9%, 97.0% and 97·6% of participants had ≥4-fold-rise in NAb titres from baseline in the 5μg-, 10μg- and 15μg-dose groups, respectively. NAb titres increased with antigen dose in younger (GMTs: 2954, 3951 and 5142 for 5μg-, 10μg- and 15μg-dose groups) but not older adults (GMTs: 1628, 1393 and 1736, respectively). NAb titres in non-naïve adults after one injection were higher than titres after two injections in naïve adults.InterpretationTwo injections of CoV2 preS dTM-AS03 demonstrated acceptable safety and reactogenicity, and robust immunogenicity in SARS-CoV-2 naïve and non-naïve adults. These results informed antigen dose selection for progression to Phase 3 evaluation of primary and booster vaccination.

Background Western Equine Encephalitis (WEE) is a naturally acquired infection and potentially devastating bioweapon, with no specific human countermeasures. An experimental inactivated Western Equine Encephalitis Vaccine (WEEV; WEE TSI-GSD 210) has been used under an IND (investigational New Drug) protocol at the United States Army Medical Research Institute of Infectious Diseases (USAMRIID) since 1976. Methods Over 24 years from 1987 to 2011, 876 subjects received 3 primary vaccine doses under 3 studies with 1,537 booster doses administered (FY87-8, phase 2, laboratory workers, vaccine lots 1-81-1, 1-81-2, and 2-1-91; FY99-12, phase 2 laboratory workers, lot 2-1-91; and FY09-02, phase 1 healthy volunteer, lot 3-1-92). Post-vaccination safety and immunogenicity [plaque reduction neutralization test 80% (PRNT80) > 1:40] were analyzed. Results Overall PRNT80 response to the primary series in FY87-8 was 42% (326/770) but dropped to 16% (14/87) in FY99-12, prompting study FY09-02, which achieved 89% (17/19). The first booster response rate was 68% (814/1194) in FY87-8, 53% (171/324) in FY99-12, and 100% (10/10) in FY09-02. The majority of definitely related adverse reactions (AEs) were mild and local with no definitely related serious AEs. No laboratory acquired WEE infection was documented during this period despite 4 reported exposures in vaccinated subjects. Conclusion The TSI-GSD 210 WEE vaccine was immunogenic, safe and well tolerated. Use of this vaccine could be considered in an emergency setting. Despite decades of safe and effective use under IND, full licensure is not planned due to manufacturing constraints, and a strategic decision to develop alternatives. Clinical trial registration https://clinicaltrials.gov/, identifier NCT01159561.

BACKGROUND Eastern equine encephalitis virus (EEEV) is a mosquito borne alphavirus spread primarily in Atlantic and Gulf Coast regions of the United States. EEEV is the causative agent of a devastating meningoencephalitis syndrome, with approximately 30% mortality and significant morbidity. There is no licensed human vaccine against EEEV. An inactivated EEEV vaccine has been offered under investigational new drug (IND) protocols at the United States Army Medical Research Institute of Infectious Diseases (USAMRIID) since 1976. METHODS Healthy at-risk laboratory personnel received inactivated PE-6 strain EEEV (TSI-GSD 104) vaccine under two separate IND protocols. Protocol FY 99-11 (2002-2008) had a primary series consisting of doses on day 0, 7, and 28. Protocol FY 06-31 (2008-2016) utilized a primary series with doses on day 0 and 28, and month 6. Participants with an inadequate immune response, plaque reduction neutralization test with 80% cut-off (PRNT80) titer

INTRODUCTION During the 2014-2016 Ebolavirus (EBOV) outbreak, several candidate therapeutics were used in EBOV-infected patients in clinical trials and under expanded access for emergency use. This review will focus briefly on medications used during the outbreak. We will discuss current therapeutic candidates and their status and will then turn to a related and essential topic: supportive care and the standard of care for filovirus infected patients. Potential benefits and pitfalls of combination therapies for filoviruses will be discussed. Areas covered: Clinical trials of therapeutics targeting EBOV; clinical usage of therapeutics during recent EBOV outbreak; potential need for combination therapy; role of supportive care in treatment of Ebola virus disease (EVD). Expert commentary: In the absence of another large scale EBOV outbreak, the path to therapeutic product licensure in the United States of America (USA) would need to be via the FDA Animal Rule. However, human data may be needed to supplement animal data. The future of filovirus therapeutics may therefore benefit by establishing the ability to implement clinical trials in an outbreak setting in a timely fashion. Supportive care guidelines for filovirus infection should be defined and established as standard of care for treatment of EVD.

Dengue fever (DF) is a mosquito-borne acute viral disease presenting with hemorrhagic manifestations in severe cases. Southeast Iran is in close proximity to Pakistan, an endemic country for DF. This cross-sectional study was conducted in the Sistan and Baluchestan province in the southeast of Iran to investigate possibility of DF (immunoglobulin M [IgM], immunoglobulin G [IgG], and nonstructural protein 1 [NS1] antigen tests) in 60 clinically suspected patients (April 2013 to August 2015). NS1 protein was detected in 5% (N = 3), at least one of the antibodies (IgM and/ or IgG) was detected in 11% (N = 7) of the samples. Five patients identified as of acutely infected. There was a simultaneous presence of NS1 protein and IgG or IgM antibodies in 4% (N = 2) of patients. Previous studies show establishment of potential vectors in this area. These evidences support the hypothesis that DF can be a health concern in Southeast Iran with potential future outbreaks.

Influenza immunization is recommended for older adults annually, and has been reported to have cardiovascular protective effects. TNF-related weak inducer of apoptosis (TWEAK), an inflammatory mediator implicated in the development of cardiovascular diseases, could be a mechanism for such effect. The objective of this study was to evaluate the effect of influenza vaccine on TWEAK levels. Older persons over 70 years of age were recruited during 2007-2008 influenza season and immunized with the standard dose trivalent inactivated influenza vaccine. Frailty was evaluated using a validated set of criteria. Sera were collected immediately before and during the 4th week after vaccination. Pre- and post-vaccination levels of TWEAK, soluble CD163 (sCD163) and strain-specific influenza antibody titers were measured in 69 participants. Multiple regression analyses were employed to examine the effect of influenza vaccine on TWEAK and sCD163, adjusting for age, sex, and hypertension. Post-vaccination TWEAK [mean ± standard deviation (SD) = 591.7 ± 290.1 pg/ml] was significantly lower than pre-vaccination level (690.6 ± 330.0 pg/ml) (p = .003). No significant difference was observed between pre and post-vaccination sCD163 levels (p = .71). Post-vaccination TWEAK levels were significantly higher in men (p = .01) and in participants with college or higher level of education (p = .044). There was no significant difference in post-vaccination TWEAK according to other demographics or pre-existing medical conditions. A 2-fold or greater antibody titer against H1N1 vaccine strain was associated with a more pronounced reduction in TWEAK at the p < .10 level (p = .091). A time by frailty interaction term (p = .091) indicated that the vaccination-induced reduction of TWEAK was greatest among frail individuals. These results of this observational study indicate that the impact of Influenza vaccine on TWEAK, including the role of specific antibody responses of specific vaccine strains and frailty status, warrants further investigation. Such investigation may elucidate whether this effect plays a role in mediating cardiovascular protection of influenza vaccination.

The presence of Crimean–Congo hemorrhagic fever virus (CCHFV) in Iran was first identified in studies of livestock sera and ticks in the 1970s, but the first human infection was not diagnosed until 1999. Since that time, the number of cases of CCHF in Iran has markedly increased. Through January 2012, articles in the published literature have reported a total of 870 confirmed cases, with 126 deaths, for a case fatality rate (CFR) of 17.6%. The disease has been seen in 26 of the country’s 31 provinces, with the greatest number of cases in Sistan and Baluchestan, Isfahan, Fars, Tehran, Khorasan, and Khuzestan provinces. The increase in CCHF in Iran has paralleled that in neighboring Turkey, though the number of cases in Turkey has been much larger, with an overall CFR of around 5%. In this article, we review the features of CCHF in Iran, including its history, epidemiology, animal and tick reservoirs, current surveillance and control programs, diagnostic methods, clinical features and experience with ribavirin therapy, and consider possible explanations for the difference in the CFR of CCHF between Iran and Turkey. The emergence of CCHF in Iran calls for countermeasures at many levels to protect the population, but also provides opportunities for studying the epidemiology, diagnosis and management of the disease.

This review was undertaken to determine the role of surgery in the treatment of brucella endocarditis. All English and French articles reporting brucella endocarditis (1966 to 2011) in PubMed, Google, and Scopus were reviewed. In all, 308 cases were identified, and linear and logistic regression was performed. Surgery improved outcomes by decreasing mortality from 32.7% in the medical treatment only group to 6.7% in the combined surgical and medical treatment group ( p

Please cite this paper as: Tavana et al. (2011) Influenza vaccination in patients with pulmonary sarcoidosis: efficacy and safety. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750-2659.2011.00290.x. Background Sarcoidosis is an inflammatory, granulomatous disorder of unknown etiology. The role of cellular and humoral immune systems in this disease is unclear, whereas dysregulation of the immune system is suggested. Patients with sarcoidosis show diverse responses while exposed to various antigens. Although influenza vaccination is recommended in pulmonary sarcoidosis, its efficacy and safety has not been investigated. Objectives To evaluate safety and immunogenicity of influenza vaccine in patients with sarcoidosis. Patients/Methods Influenza vaccination was performed in 23 eligible patients with sarcoidosis (SP) and 26 healthy controls (HC). Antibody titers against H1N1, H3N2, and B influenza virus antigens were evaluated just before and 1 month after vaccination. Patients were followed for 6 months to assess vaccine safety. Results Serological response and magnitude of changes in antibody titers against influenza vaccine antigens were comparable between SPs and HCs. Women showed a better serological response against B antigen (P = 0·034) than men. Twenty-four-hour urine calcium was associated with antibody response against H1N1 [correlation coefficient (CC) = 0·477, P = 0·003] and H3N2 (CC = 0·352, P = 0·028) antigens. Serum angiotensin-converting enzyme correlated negatively with antibody response against B antigen (CC = −0·331, P = 0·040). Higher residual volume was associated with fewer rises in antibody titer against H3N2 antigen (CC = −0·377, P = 0·035). No major adverse events or disease flare-up was observed during follow-up. Conclusions In this study, influenza vaccination did not cause any major adverse event in SPs, and their serological response was equal to HCs. Studies with larger sample size and a broader selection of subjects could help validate the results of this study.

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease caused by CCHF virus (CCHFV), a nairovirus in the family Bunyaviridae. CCHF occurs sporadically in a number of countries in Asia, the Middle East, southeastern Europe and Africa. Patients may develop subclinical to severe hemorrhagic disease, with fatal outcomes in a substantial percentage of cases. Transmission usually occurs through contact with viremic livestock or patients or bites by infected ticks. The number of reported cases has increased in recent years, possibly due to global climatic change and human perturbations of biocenoses that may have led to the migration of tick vectors. There is currently no FDA-approved vaccine or specific antiviral therapy for CCHF. The classification of CCHFV as a WHO Risk Group IV pathogen and the lack of suitable animal models has caused progress in developing new prophylactic and therapeutic measures to be slow. Ribavirin is active against CCHFV in vitro, but its efficacy for human therapy has not been definitively demonstrated by clinical studies. CCHF-immunoglobulin is also in use, but without clear evidence of efficacy. In this article, we review the development of prophylaxis and therapy for CCHF and discuss future prospects for vaccine and drug development.

Background From 2004 to 2005, an outbreak of Marburg virus, a filovirus, in Angola led to a case-fatality rate of 90 percent. However, little information is available regarding the virulence of the Angola strain from this outbreak compared with the virulence of other strains. Therefore, we sought to assess time to selected outcomes in non-human primates (NHPs) experimentally infected with either Angola or Musoke Marburg strains. Methods Between 2012 and 2017, nine therapeutic trials at the US Army Medical Research Institute of Infectious Diseases were conducted in Macaca fascicularis monkeys challenged with 1 to 10,000 plaque forming units of Marburg virus administered intramuscularly. The current study population was comprised of 90 control NHPs, of which, 61 were administered Angola strain in four separate trials and 29 with Musoke strain in five trials. Clinical responses including development of rash and oral intake were collected following infection. The primary outcome of interest was time to death or euthanasia post-inoculation between strains evaluated using Cox proportional hazards regression. Secondary endpoints included time to development of a petechial rash and time to decreased appetite. Results Following Marburg virus challenge, all NHPs died and most NHPs experienced decreased food consumption (97%), and petechial rash (96%). The median time to death for Angola-infected NHPs was 8.9 days (25th, 75th percentiles: 7.9, 9.3), whereas Musoke-infected NHPs survived for a median of 10.0 days (25th, 75th percentiles: 9.0, 10.9) (Figure 1). Irrespective of strain, petechial rash was preceded by decreased food consumption by 0.7 days (SD 1.5) on average. Angola strain was associated with statistically significant earlier death (adjusted HR = 21.8; 95% CI: 8.9, 53.2), earlier development of petechiae (adjusted HR = 17.6; 95% CI: 7.0, 44.5) and earlier loss of appetite (adjusted HR = 5.8; 95% CI: 2.9,11.7). Conclusion This was the first study to compare survival and clinical characteristics in NHPs between these strains. Despite sharing the similar genetic lineage, our data strongly supports increased virulence of Angola strain compared with Musoke strain. Pathophysiological mechanisms involved in increased virulence require further study. Disclosures All authors: No reported disclosures.

Crimean-Congo hemorrhagic fever (CCHF) is a viral disease with several different modes of transmission. We describe the manifestations, outcome, and likely modes of transmission for three nosocomial cases. All threee cases were healthcare workers (two men and one woman). They had fever, myalgia, and petechia. Disseminated intravascular coagulation resulted in the death occurred in the woman. Because this disease is manifested with non-specific influenza-like symptoms, diagnosis can be difficult. Data for these patients can be used to investigate airborne or sexual transmission of this virus, although neither route was substantiated for these patients. Use of universal precautions and early case detection are the most helpful strategy for preventing nosocomial transmission of CCHF.

Several recent studies have suggested that an association exists between Helicobacter pylori (HP) eradication and improvement in platelet count in a significant proportion of patients with idiopathic thrombocytopenic purpura (ITP). In this controlled study, we prospectively examined adult patients with chronic ITP for HP infection, and assessed the effect of HP eradication on platelet count. One hundred forty-two consecutive Iranian patients with chronic ITP were assessed. Those who met the criteria and had platelet counts >30 x 10(9)/L within the medication-free screening month were enrolled (n = 129; 66 females; mean age, 29.2 +/- 7.0 years). HP-positive patients received a 2-week course of triple HP eradication therapy (i.e., amoxicillin, clarithromycin, and omeprazole) and were followed for 48 weeks. An ITP response was defined as a platelet count of >100 x 10(9)/L 24 weeks after treatment, together with an increase in the platelet count >30 x 10(9)/L over the baseline value. HP infection was detected in 79 (61%) patients. HP-positive patients were significantly older than HP-negative subjects (P = 0.018). HP eradication was successful in 87% (62/71) of those who completed the eradication therapy. Whereas 48% (30/62) of HP-eradicated patients showed an ITP response, no HP-negative patient had an ITP response. The ITP response persisted for 48 weeks in 93% (28/30) of the responders. The ITP responders had a shorter disease duration than the nonresponders (P = 0.002). The management of mild-to-moderate chronic ITP in Iranian patients, especially those with a recent onset of disease, should include an investigation for and eradication of infection with HP.

Aims: We aimed to assess humoral immune response to the influenza vaccine in adult kidney transplant recipients (KTRs) subjected to two immunosuppressive regimens containing either mycophenolate mofetil (MMF) or azathioprine (Aza). Methods: 40 eligible KTRs (24 treated with Aza [KTRs-Aza] and 16 treated with MMF [KTRs-MMF]) and 40 matched healthy controls (HCs) were administered the trivalent 2006–2007 anti-influenza vaccine. Antibody (Ab) titers were measured before (pre-vacc) and 1 month after (post-vacc) vaccination. The proportion of protective Ab titers (i.e. ≧1:40), the serological response (i.e. ≧4-fold rise in titers) rates, and the magnitudes of change in titers were evaluated. Results: KTRs and HCs were similar in serologic responses, magnitudes of change in Ab titers, and proportions of acquired protective titers against all antigens. Whereas KTRs-MMF and KTRs-Aza were identical in magnitude of rise in titers as well as in serologic responses, KTRs-MMF did poorer in developing post-vacc-protective titers against A/H1N1 (p < 0.05). The function of the transplanted kidney has not deteriorated after vaccination. Conclusions: Anti-influenza vaccination was safe in KTRs and evoked Ab responses comparable to those of HCs. KTRs-MMF and KTRs-Aza responded almost equally to the vaccine. Annual anti-influenza vaccination can be recommended to all stable KTRs.

Context: Ebola hemorrhagic fever (EHF) is amongst severe and fatal viral hemorrhagic fevers. In February 2014, a strain of the Ebola virus appeared in Guinea and then in Liberia, Sierra Leone, and Mali. The aim of this study was to review the literature on EHF and discuss its routes of transmission and prevention. Evidence Acquisition: We searched medical databases (PubMed, Scopus) from July 1970 to July 2014. The key words for the literature search were as follows; Ebola hemorrhagic fever, epidemiology, transmission routes, clinical manifestation, treatment and prophylaxis. Results: On the basis of the literature search, the researchers believe that bats are the most likely reservoir. Four of five subspecies of Ebola virus have caused disease in humans. Manifestation of Ebola begins abruptly with a sudden onset of an influenza-like syndrome characterized by general malaise, fever, sore throat, severe headache, joint pain, muscle pain and chest pain. There is no Ebola virus specific treatment. Treatment is usually supportive and includes minimizing invasive procedures, and balancing fluids and electrolytes. Adequate sterilization procedures isolate patients and this is a major step towards prevention of transmission of virus to other people. Conclusions: Ebola viruses are highly contagious. Understanding the epidemiology, clinical presentation, prompt diagnosis, suitable treatment and isolation are the main factors for prevention of death and transmission of virus to other people.

Tuberculosis (TB) is the most common cause of infection-related death worldwide. Children represent 5 to 15% of all TB cases around the world and are more frequently infected and more easily affected by the most severe forms of the disease such as meningitis and disseminated form .Here, we reviewed TB in children with impact on the routes of transmission, clinical manifestations, treatment, control, and prophylaxis. Electronic databases (PubMed, Scopus) were searched from June1995 to May 2014 by using key words (pulmonaryTB,epidemiology,transmission,clinical manifestations,treatment,control, and prophylaxis) . Pulmonary tuberculosis may manifest in several forms, including endobronchial TB with focal lymphadenopathy, progressive pulmonary disease, pleural involvement, and reactivated pulmonary disease . Symptoms of primary pulmonary disease in the pediatric population are often insignificant. Gastric aspirates are used instead of sputum in children younger than 6 years. BCG vaccination is used in many parts of the world and the major role of vaccination is the prevention of life-threatening illness such as disseminated TB and meningitis in children.Treatment is the same as for adults. Most people infected with M .tuberculosis do not develop active disease. In healthy individuals, the lifetime risk of developing infection to disease is 5-10%. Reactivation of TB often occurs in older children and adolescent and is more common in patients who acquire TB at age 7 years and older.

Crimean-Congo hemorrhagic fever is a tick-borne viral disease reported from more than 30 countries in Africa, Asia, South-East Europe, and the Middle East. The majority of human cases are workers in livestock industry, agriculture, slaughterhouses, and veterinary practice. The current mortality rate in endemic areas varies between 5 to 20 percent depending on the geographic location and medical supportive treatment. Unfortunately, there is currently no FDA-approved vaccine for prevention or specific antiviral drug for the treatment of CCHF. Ribavirin, effective against CCHFV in vitro, is one of the few options for treatment of CCHFV, but its efficacy is still questionable due to contradictory clinical studies. The efficacy of other options including Intravenous Immuneglobulin (IVIG), steroids, CCHF hyperimmuneglobulin, and CCHF monoclonal antibodies is still controversial.

Among nontraditional cardiovascular risk factors, recent influenzalike infection is associated with fatal and nonfatal atherothrombotic events.To determine if influenza vaccination is associated with prevention of cardiovascular events.A systematic review and meta-analysis of MEDLINE (1946-August 2013), EMBASE (1947-August 2013), and the Cochrane Library Central Register of Controlled Trials (inception-August 2013) for randomized clinical trials (RCTs) comparing influenza vaccine vs placebo or control in patients at high risk of cardiovascular disease, reporting cardiovascular outcomes either as efficacy or safety events.Two investigators extracted data independently on trial design, baseline characteristics, outcomes, and safety events from published manuscripts and unpublished supplemental data. High-quality studies were considered those that described an appropriate method of randomization, allocation concealment, blinding, and completeness of follow-up.Random-effects Mantel-Haenszel risk ratios (RRs) and 95% CIs were derived for composite cardiovascular events, cardiovascular mortality, all-cause mortality, and individual cardiovascular events. Analyses were stratified by subgroups of patients with and without a history of acute coronary syndrome (ACS) within 1 year of randomization.Five published and 1 unpublished randomized clinical trials of 6735 patients (mean age, 67 years; 51.3% women; 36.2% with a cardiac history; mean follow-up time, 7.9 months) were included. Influenza vaccine was associated with a lower risk of composite cardiovascular events (2.9% vs 4.7%; RR, 0.64 [95% CI, 0.48-0.86], P = .003) in published trials. A treatment interaction was detected between patients with (RR, 0.45 [95% CI, 0.32-0.63]) and without (RR, 0.94 [95% CI, 0.55-1.61]) recent ACS (P for interaction = .02). Results were similar with the addition of unpublished data.In a meta-analysis of RCTs, the use of influenza vaccine was associated with a lower risk of major adverse cardiovascular events. The greatest treatment effect was seen among the highest-risk patients with more active coronary disease. A large, adequately powered, multicenter trial is warranted to address these findings and assess individual cardiovascular end points.

Safety of and humoral immune response to the anti-influenza vaccine in coronary artery disease (CAD) patients were evaluated. The trivalent vaccine was administered to 137 eligible CAD patients and 67 age- and sex-matched healthy individuals. Antibody (Ab) titers were measured before and 1 month after vaccination. CAD and HC groups were not significantly different in serologic response and magnitude of change in antibody titers against each of the vaccine antigens. In multivariate analyses, regular exercise and using multivitamin supplements were independently associated with better antibody response among CAD patients. There were no major cardiac or general adverse effects. Influenza vaccine was found safe in CAD patients and antibody responses were similar to HCs.

This study aimed to investigate the clinical and epidemiologic features of Crimean-Congo hemorrhagic fever among 34 children and adolescents (mean age, 13.3 +/- 4.6 years) from a highly endemic region. Clinical manifestations were similar to those in adults. The case-fatality ratio was 26.5% (9 of 34). Compared with adult patients, children and adolescents may be more vulnerable to severe and fatal Crimean-Congo hemorrhagic fever.

Hemolytic uremic syndrome (HUS) can be associated with different infectious etiologies, but the relationship between pseudomembranous colitis and HUS was first described in the 1970s in some childhood patients. There is very limited published literature on Clostridium difficile-associated HUS. We report a case of C. difficile-related HUS in an adult patient and provide a review of the literature.Keywords: hemolytic uremic syndrome; Clostridium difficile; colitis(Published: 15 October 2012)Citation: Journal of Community Hospital Internal Medicine Perspectives 2012, 2: 19064 - http://dx.doi.org/10.3402/jchimp.v2i3.19064

Background This is an update of the original review published in 2008. The risk of adverse cardiovascular outcomes is increased with influenza-like infection, and vaccination against influenza may improve cardiovascular outcomes. Objectives To assess the potential benefits of influenza vaccination for primary and secondary prevention of cardiovascular disease. Search methods We searched the following electronic databases on 18 October 2013: The Cochrane Library (including Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Reviews of Effects (DARE), Economic Evaluation Database (EED) and Health Technology Assessment database (HTA)), MEDLINE, EMBASE, Science Citation Index Expanded, Conference Proceedings Citation Index – Science and ongoing trials registers (www.controlled-trials.com/ and www.clinicaltrials.gov). We examined reference lists of relevant primary studies and systematic reviews. We performed a limited PubMed search on 20 February 2015, just before publication. Selection criteria Randomised controlled trials (RCTs) of influenza vaccination compared with placebo or no treatment in participants with or without cardiovascular disease, assessing cardiovascular death or non-fatal cardiovascular events. Data collection and analysis We used standard methodological procedures as expected by The Cochrane Collaboration. We carried out meta-analyses only for cardiovascular death, as other outcomes were reported too infrequently. We expressed effect sizes as risk ratios (RRs), and we used random-effects models. Main results We included eight trials of influenza vaccination compared with placebo or no vaccination, with 12,029 participants receiving at least one vaccination or control treatment. We included six new studies (n = 11,251), in addition to the two included in the previous version of the review. Four of these trials (n = 10,347) focused on prevention of influenza in the general or elderly population and reported cardiovascular outcomes among their safety analyses; four trials (n = 1682) focused on prevention of cardiovascular events in patients with established coronary heart disease. These populations were analysed separately. Follow-up continued between 42 days and one year. Five RCTs showed deficits in at least three of the risk of bias criteria assessed. When reported (seven studies), vaccination provided adequate immunogenicity or protection against influenza. Cardiovascular mortality was reported by four secondary prevention trials and was significantly reduced by influenza vaccination overall (risk ratio (RR) 0.45, 95% confidence interval (CI) 0.26 to 0.76; P value 0.003) with no significant heterogeneity between studies, and by three trials reporting cardiovascular mortality as part of their safety analyses when the numbers of events were too small to permit conclusions. In studies of patients with coronary heart disease, composite outcomes of cardiovascular events tended to be decreased with influenza vaccination compared with placebo. Generally no significant difference was found between comparison groups regarding individual outcomes such as myocardial infarction. Authors' conclusions In patients with cardiovascular disease, influenza vaccination may reduce cardiovascular mortality and combined cardiovascular events. However, studies had some risk of bias, and results were not always consistent, so additional higher-quality evidence is necessary to confirm these findings. Not enough evidence was available to establish whether influenza vaccination has a role to play in the primary prevention of cardiovascular disease.