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The Cochrane Database of Systematic... Apr 2009Anthrax is a bacterial zoonosis that occasionally causes human disease and is potentially fatal. Anthrax vaccines include a live-attenuated vaccine, an alum-precipitated... (Review)
Review
BACKGROUND
Anthrax is a bacterial zoonosis that occasionally causes human disease and is potentially fatal. Anthrax vaccines include a live-attenuated vaccine, an alum-precipitated cell-free filtrate vaccine, and a recombinant protein vaccine.
OBJECTIVES
To evaluate the effectiveness, immunogenicity, and safety of vaccines for preventing anthrax.
SEARCH STRATEGY
We searched the following databases (November 2008): Cochrane Infectious Diseases Group Specialized Register; CENTRAL (The Cochrane Library 2008, Issue 4); MEDLINE; EMBASE; LILACS; and mRCT. We also searched reference lists.
SELECTION CRITERIA
We included randomized controlled trials (RCTs) of individuals and cluster-RCTs comparing anthrax vaccine with placebo, other (non-anthrax) vaccines, or no intervention; or comparing administration routes or treatment regimens of anthrax vaccine.
DATA COLLECTION AND ANALYSIS
Two authors independently considered trial eligibility, assessed risk of bias, and extracted data. We presented cases of anthrax and seroconversion rates using risk ratios (RR) and 95% confidence intervals (CI). We summarized immunoglobulin G (IgG) concentrations using geometric means. We carried out a sensitivity analysis to investigate the effect of clustering on the results from one cluster-RCT. No meta-analysis was undertaken.
MAIN RESULTS
One cluster-RCT (with 157,259 participants) and four RCTs of individuals (1917 participants) met the inclusion criteria. The cluster-RCT from the former USSR showed that, compared with no vaccine, a live-attenuated vaccine (called STI) protected against clinical anthrax whether given by a needleless device (RR 0.16; 102,737 participants, 154 clusters) or the scarification method (RR 0.25; 104,496 participants, 151 clusters). Confidence intervals were statistically significant in unadjusted calculations, but when a small amount of association within clusters was assumed, the differences were not statistically significant. The four RCTs (of individuals) of inactivated vaccines (anthrax vaccine absorbed and recombinant protective antigen) showed a dose response relationship for the anti-protective antigen IgG antibody titre. Intramuscular administration was associated with fewer injection site reactions than subcutaneous injection, and injection site reaction rates were lower when the dosage interval was longer.
AUTHORS' CONCLUSIONS
One cluster-RCT provides limited evidence that a live-attenuated vaccine is effective in preventing cutaneous anthrax. Vaccines based on anthrax antigens are immunogenic in most vaccinees with few adverse events or reactions. Ongoing randomized controlled trials are investigating the immunogenicity and safety of anthrax vaccines.
Topics: Anthrax; Anthrax Vaccines; Humans; Randomized Controlled Trials as Topic; Vaccines, Attenuated
PubMed: 19370633
DOI: 10.1002/14651858.CD006403.pub2 -
Hong Kong Medical Journal = Xianggang... Dec 2019
Topics: Adolescent; Age Factors; Child; Child, Preschool; Hong Kong; Humans; Immunization Programs; Influenza Vaccines; Influenza, Human; Pandemics; Strategic Stockpile; Time Factors; Vaccines, Attenuated; Young Adult
PubMed: 31889031
DOI: No ID Found -
Annual Review of Microbiology 1996Varicella-zoster virus (VZV) is a ubiquitous human pathogen that causes varicella, commonly called chicken pox; establishes latency; and reactivates as herpes zoster,... (Review)
Review
Varicella-zoster virus (VZV) is a ubiquitous human pathogen that causes varicella, commonly called chicken pox; establishes latency; and reactivates as herpes zoster, referred to as shingles. A live attenuated varicella vaccine, derived from the Oka strain of VZV has clinical efficacy for the prevention of varicella. The vaccine induces persistent immunity to VZV in healthy children and adults. Immunization against VZV also has the potential to lower the risk of reactivation of latent virus. The varicella vaccine may eventually reduce or eliminate herpes zoster, which is a serious problem for elderly and immunocompromised individuals.
Topics: Adult; Canada; Chickenpox; Chickenpox Vaccine; Child; Herpes Zoster; Humans; United States; Vaccination; Vaccines, Attenuated; Virus Latency
PubMed: 8905076
DOI: 10.1146/annurev.micro.50.1.59 -
International Journal of Molecular... Jun 2022Influenza is still a frequent seasonal infection of the upper respiratory tract, which may have deadly consequences, especially for the elderly. This is in spite of the... (Review)
Review
Influenza is still a frequent seasonal infection of the upper respiratory tract, which may have deadly consequences, especially for the elderly. This is in spite of the availability of vaccines suggested for persons above 65 years of age. Two types of conventional influenza vaccines are currently licensed for use-live attenuated and inactivated vaccines. Depending on local regulatory requirements, live attenuated vaccines are produced by the reverse genetics technique or by classical reassortment in embryonated chicken eggs. Sometimes, the efficiency of classical reassortment is complicated by certain properties of the wild-type parent virus. Cases of low efficacy of vaccines have been noted, which, among other reasons, may be associated with suboptimal properties of the wild-type parent virus that are not considered when recommendations for influenza vaccine composition are made. Unfortunately, knowledge surrounding the roles of properties of the circulating influenza virus and its impact on the efficacy of the reassortment process, vaccination efficiency, the infectivity of the vaccine candidates, etc., is now scattered in different publications. This review summarizes the main features of the influenza virus that may dramatically affect different aspects of the preparation of egg-derived live attenuated vaccine candidates and their effectiveness. The author expresses her personal view, which may not coincide with the opinion of other experts in the field of influenza vaccines.
Topics: Aged; Female; Humans; Influenza Vaccines; Influenza, Human; Vaccination; Vaccines, Attenuated; Vaccines, Inactivated
PubMed: 35743258
DOI: 10.3390/ijms23126815 -
Frontiers in Immunology 2022Live vaccines use attenuated microbes to acquire immunity against pathogens in a safe way. As live attenuated vaccines (LAVs) still maintain infectivity, the vaccination... (Review)
Review
Live vaccines use attenuated microbes to acquire immunity against pathogens in a safe way. As live attenuated vaccines (LAVs) still maintain infectivity, the vaccination stimulates diverse immune responses by mimicking natural infection. Induction of pathogen-specific antibodies or cell-mediated cytotoxicity provides means of specific protection, but LAV can also elicit unintended off-target effects, termed non-specific effects. Such mechanisms as short-lived genetic interference and non-specific innate immune response or long-lasting trained immunity and heterologous immunity allow LAVs to develop resistance to subsequent microbial infections. Based on their safety and potential for interference, LAVs may be considered as an alternative for immediate mitigation and control of unexpected pandemic outbreaks before pathogen-specific therapeutic and prophylactic measures are deployed.
Topics: Immunity; Immunity, Heterologous; Vaccination; Vaccines, Attenuated
PubMed: 35651619
DOI: 10.3389/fimmu.2022.877845 -
Microbiology Spectrum Oct 2022The yellow fever (YF) live attenuated vaccine strain 17D (termed 17D) has been widely used for the prevention and control of YF disease. However, 17D retains significant...
The yellow fever (YF) live attenuated vaccine strain 17D (termed 17D) has been widely used for the prevention and control of YF disease. However, 17D retains significant neurovirulence and viscerotropism in mice, which is probably linked to the increased occurrences of serious adverse events following 17D vaccination. Thus, the development of an updated version of the YF vaccine with an improved safety profile is of high priority. Here, we generated a viable bicistronic YF virus (YFV) by incorporating the internal ribosome entry site (IRES) from virus into an infectious clone of YFV 17D. The resulting recombinant virus, 17D-IRES, exhibited similar replication efficiency to its parental virus (17D) in mammalian cell lines, while it was highly restricted in mosquito cells. Serial passage of 17D-IRES in BHK-21 cells showed good genetic stability. More importantly, in comparison with the parental 17D, 17D-IRES displayed significantly decreased mouse neurovirulence and viscerotropism in type I interferon (IFN)-signaling-deficient and immunocompetent mouse models. Interestingly, 17D-IRES showed enhanced sensitivity to type I IFN compared with 17D. Moreover, immunization with 17D-IRES provided solid protection for mice against a lethal challenge with YFV. These preclinical data support further development of 17D-IRES as an updated version for the approved YF vaccine. This IRES-based attenuation strategy could be also applied to the design of live attenuated vaccines against other mosquito-borne flaviviruses. Yellow fever (YF) continually spreads and causes epidemics around the world, posing a great threat to human health. The YF live attenuated vaccine 17D is considered the most efficient vaccine available and helps to successfully control disease epidemics. However, side effects may occur after vaccination, such as viscerotropic disease (YEL-AVD) and neurotropic adverse disease (YEL-AND). Thus, there is an urgent need for a safer YF vaccine. Here, an IRES strategy was employed, and a bicistronic YFV was successfully developed (named 17D-IRES). 17D-IRES showed effective replication and genetic stability and high attenuation . Importantly, 17D-IRES induced humoral and cellular immune responses and conferred full protection against lethal YFV challenge. Our study provides data suggesting that 17D-IRES, with its prominent advantages, could be a vaccine candidate against YF. Moreover, this IRES-based bicistronic technology platform represents a promising strategy for developing other live attenuated vaccines against emerging viruses.
Topics: Mice; Humans; Animals; Yellow Fever; Vaccines, Attenuated; Internal Ribosome Entry Sites; Yellow Fever Vaccine; Yellow fever virus; Antigens, Viral; Interferon Type I; Mammals
PubMed: 35980184
DOI: 10.1128/spectrum.02246-22 -
Human Vaccines & Immunotherapeutics Nov 2016Antigenic drift of seasonal influenza viruses and the occasional introduction of influenza viruses of novel subtypes into the human population complicate the timely... (Review)
Review
Antigenic drift of seasonal influenza viruses and the occasional introduction of influenza viruses of novel subtypes into the human population complicate the timely production of effective vaccines that antigenically match the virus strains that cause epidemic or pandemic outbreaks. The development of game-changing vaccines that induce broadly protective immunity against a wide variety of influenza viruses is an unmet need, in which recombinant viral vectors may provide. Use of viral vectors allows the delivery of any influenza virus antigen, or derivative thereof, to the immune system, resulting in the optimal induction of virus-specific B- and T-cell responses against this antigen of choice. This systematic review discusses results obtained with vectored influenza virus vaccines and advantages and disadvantages of the currently available viral vectors.
Topics: Animals; Drug Carriers; Genetic Vectors; Humans; Influenza Vaccines; Vaccines, Attenuated; Vaccines, Synthetic; Viruses
PubMed: 27455345
DOI: 10.1080/21645515.2016.1210729 -
The Cochrane Database of Systematic... Jun 2018Influenza vaccinations are currently recommended in the care of people with COPD, but these recommendations are based largely on evidence from observational studies,... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Influenza vaccinations are currently recommended in the care of people with COPD, but these recommendations are based largely on evidence from observational studies, with very few randomised controlled trials (RCTs) reported. Influenza infection causes excess morbidity and mortality in people with COPD, but there is also the potential for influenza vaccination to cause adverse effects, or not to be cost effective.
OBJECTIVES
To determine whether influenza vaccination in people with COPD reduces respiratory illness, reduces mortality, is associated with excess adverse events, and is cost effective.
SEARCH METHODS
We searched the Cochrane Airways Trials Register, two clinical trials registries, and reference lists of articles. A number of drug companies we contacted also provided references. The latest search was carried out in December 2017.
SELECTION CRITERIA
RCTs that compared live or inactivated virus vaccines with placebo, either alone or with another vaccine, in people with COPD.
DATA COLLECTION AND ANALYSIS
Two review authors independently extracted data. All entries were double-checked. We contacted study authors and drug companies for missing information. We used standard methods expected by Cochrane.
MAIN RESULTS
We included 11 RCTs with 6750 participants, but only six of these included people with COPD (2469 participants). The others were conducted on elderly and high-risk individuals, some of whom had chronic lung disease. Interventions compared with placebo were inactivated virus injections and live attenuated intranasal virus vaccines. Some studies compared intra-muscular inactivated vaccine and intranasal live attenuated vaccine with intra-muscular inactivated vaccine and intranasal placebo. Studies were conducted in the UK, USA and Thailand.Inactivated vaccine reduced the total number of exacerbations per vaccinated participant compared with those who received placebo (mean difference (MD) -0.37, 95% confidence interval (CI) -0.64 to -0.11; P = 0.006; two RCTs, 180 participants; low quality evidence). This was due to the reduction in 'late' exacerbations, occurring after three or four weeks (MD -0.39, 95% CI -0.61 to -0.18; P = 0.0004; two RCTs, 180 participants; low quality evidence). Both in people with COPD, and in older people (only a minority of whom had COPD), there were significantly more local adverse reactions in people who had received the vaccine, but the effects were generally mild and transient.There was no evidence of an effect of intranasal live attenuated virus when this was added to inactivated intramuscular vaccination.Two studies evaluating mortality for influenza vaccine versus placebo were too small to have detected any effect on mortality. However, a large study (N=2215) noted that there was no difference in mortality when adding live attenuated virus to inactivated virus vaccination, AUTHORS' CONCLUSIONS: It appeared, from the limited number of RCTs we were able to include, all of which were more than a decade old, that inactivated vaccine reduced exacerbations in people with COPD. The size of effect was similar to that seen in large observational studies, and was due to a reduction in exacerbations occurring three or more weeks after vaccination, and due to influenza. There was a mild increase in transient local adverse effects with vaccination, but no evidence of an increase in early exacerbations. Addition of live attenuated virus to the inactivated vaccine was not shown to confer additional benefit.
Topics: Aged; Disease Progression; Humans; Influenza Vaccines; Influenza, Human; Lung Diseases, Obstructive; Randomized Controlled Trials as Topic; Vaccines, Attenuated; Vaccines, Inactivated
PubMed: 29943802
DOI: 10.1002/14651858.CD002733.pub3 -
Human Vaccines & Immunotherapeutics Dec 2024Few papers focus their attention on VZV vaccination effectiveness among people living with HIV (PLWH). Flanking the live attenuated vaccine (VZL) available, a newly... (Review)
Review
Few papers focus their attention on VZV vaccination effectiveness among people living with HIV (PLWH). Flanking the live attenuated vaccine (VZL) available, a newly recombinant vaccine (RZV) was recently introduced and approved for HZ prevention among adults. PLWH represents a population on which a particular attention should be applied, in order to guarantee the vaccine efficacy and safety. We performed a literature search in USNLM, PubMed, PubMed Central, PMC and Cochrane Library. From all the publications found eligible, data were extracted and processed per population, vaccine type, immunogenicity and ADRs. The review of the 13 included studies shows that both RZV and VZL are immunogenic and have an acceptable safety profile in adults and children living with HIV. However, given the lack of research available about vaccine efficacy in preventing VZV and HZ in PLWH, additional studies need to be performed, in order to achieve a full completeness of data.
Topics: Humans; Vaccines, Attenuated; HIV Infections; Herpes Zoster Vaccine; Vaccines, Synthetic; Herpes Zoster; Vaccines, Inactivated; Immunogenicity, Vaccine; Vaccine Efficacy; Herpesvirus 3, Human; Adult; Child; Vaccination; Chickenpox Vaccine
PubMed: 38650460
DOI: 10.1080/21645515.2024.2341456 -
Pediatric Nephrology (Berlin, Germany) Dec 2023The use of live attenuated vaccines in patients with immunosuppressive agents is contraindicated in package inserts and guidelines in Japan and other countries. However,... (Review)
Review
The use of live attenuated vaccines in patients with immunosuppressive agents is contraindicated in package inserts and guidelines in Japan and other countries. However, patients receiving immunosuppressants have a high risk of infectious disease becoming severe, and the necessity to prevent infectious disease is high. To date, 2,091 vaccinations have been reported in 25 reports of live attenuated vaccines in people receiving immunosuppressants. Twenty-three patients (1.1%) became infected with the virus strain used in the vaccine, which was varicella virus in 21 patients. No reports have described life-threatening complications. A prospective study at the National Center for Child Health and Development conducted under certain immunological conditions (CD4 cell count ≥ 500/mm, stimulation index of lymphocyte blast transformation by phytohemagglutinin (PHA) ≥ 101.6, serum immunoglobulin G ≥ 300 mg/dL) confirmed the serological effectiveness and safety. The evidence suggests that live attenuated vaccines can be used even in combination with immunosuppressants. Further evidence must be gathered and immunological criteria investigated to determine the conditions for safe use. Depending on the results of these investigations, the wording in package inserts and guidelines may need to be revised.
Topics: Child; Humans; Immunosuppressive Agents; Vaccines, Attenuated; Prospective Studies; Immune System Diseases; Communicable Diseases
PubMed: 37076756
DOI: 10.1007/s00467-023-05969-z