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BMJ Clinical Evidence Apr 2011Chickenpox is extremely contagious. Over 90% of unvaccinated people become infected, but infection occurs at different ages in different parts of the world - over 80%... (Review)
Review
INTRODUCTION
Chickenpox is extremely contagious. Over 90% of unvaccinated people become infected, but infection occurs at different ages in different parts of the world - over 80% of people have been infected by the age of 10 years in the US, the UK, and Japan, and by the age of 20 to 30 years in India, South East Asia, and the West Indies.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent chickenpox in healthy adults and children? What are the effects of interventions to prevent chickenpox in children exposed prenatally? What are the effects of interventions to prevent chickenpox in immunocompromised adults and children? What are the effects of treatments for chickenpox in healthy adults and children? What are the effects of treatments for chickenpox in immunocompromised adults and children? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2010 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS
We found 11 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic review we present information relating to the effectiveness and safety of the following interventions: aciclovir, famciclovir, live attenuated vaccine, valaciclovir, and varicella zoster immunoglobulin.
Topics: Chickenpox; Chickenpox Vaccine; Evidence-Based Medicine; Humans; Immunocompromised Host; Incidence; India; Vaccines, Attenuated
PubMed: 21486500
DOI: No ID Found -
Cell Host & Microbe Apr 2018One outcome of the many advances in basic sciences that have been made over the last decades is the prospect of rational vaccine design. A recent publication by Du...
One outcome of the many advances in basic sciences that have been made over the last decades is the prospect of rational vaccine design. A recent publication by Du et al. (2018) describes a screening method for selection of live-attenuated viral vaccine platforms with enhanced immune-stimulatory properties.
Topics: Vaccines, Attenuated; Viral Vaccines
PubMed: 29649438
DOI: 10.1016/j.chom.2018.03.017 -
Expert Review of Vaccines Sep 2016A novel vaccine platform uses DNA immunization to launch live-attenuated virus vaccines in vivo. This technology has been applied for vaccine development against... (Review)
Review
A novel vaccine platform uses DNA immunization to launch live-attenuated virus vaccines in vivo. This technology has been applied for vaccine development against positive-strand RNA viruses with global public health impact including alphaviruses and flaviviruses. The DNA-launched vaccine represents the recombinant plasmid that encodes the full-length genomic RNA of live-attenuated virus downstream from a eukaryotic promoter. When administered in vivo, the genomic RNA of live-attenuated virus is transcribed. The RNA initiates limited replication of a genetically defined, live-attenuated vaccine virus in the tissues of the vaccine recipient, thereby inducing a protective immune response. This platform combines the strengths of reverse genetics, DNA immunization and the advantages of live-attenuated vaccines, resulting in a reduced chance of genetic reversions, increased safety, and improved immunization. With this vaccine technology, the field of DNA vaccines is expanded from those that express subunit antigens to include a novel type of DNA vaccines that launch live-attenuated viruses.
Topics: Animals; Humans; Plasmids; RNA Virus Infections; RNA Viruses; RNA, Viral; Vaccines, Attenuated; Vaccines, DNA; Viral Vaccines
PubMed: 27055100
DOI: 10.1080/14760584.2016.1175943 -
Human Vaccines & Immunotherapeutics Dec 2022Despite the existence of a highly efficient yellow fever vaccine, yellow fever reemergence throughout Africa and the Americas has put 900 million people in 47 countries... (Review)
Review
Despite the existence of a highly efficient yellow fever vaccine, yellow fever reemergence throughout Africa and the Americas has put 900 million people in 47 countries at risk of contracting the disease. Although the vaccine has been key to controlling yellow fever epidemics, its live-attenuated nature comes with a range of contraindications that prompts advising against its administration to pregnant and lactating women, immunocompromised individuals, and those with hypersensitivity to chicken egg proteins. Additionally, large outbreaks have highlighted problems with insufficient vaccine supply, whereby manufacturers rely on slow traditional manufacturing processes that prevent them from ramping up production. These limitations have contributed to an inadequate control of yellow fever and have favored the pursuit of novel yellow fever vaccine candidates that aim to circumvent the licensed vaccine's restrictions. Here, we review the live-attenuated vaccine's limitations and explore the epitome of a yellow fever vaccine, whilst scrutinizing next-generation vaccine candidates.
Topics: Disease Outbreaks; Female; Humans; Lactation; Vaccines, Attenuated; Yellow Fever; Yellow Fever Vaccine; Yellow fever virus
PubMed: 33974507
DOI: 10.1080/21645515.2021.1895644 -
Viral Immunology Mar 2018Varicella zoster virus (VZV) is the cause of chickenpox (varicella) and shingles (zoster), and was once responsible for over 4 million infections in the United States... (Review)
Review
Varicella zoster virus (VZV) is the cause of chickenpox (varicella) and shingles (zoster), and was once responsible for over 4 million infections in the United States annually. The development of a live attenuated VZV vaccine was initially viewed with extreme skepticism. Nonetheless, a VZV vaccine was developed in the 1970s by Takahashi and his colleagues in Japan and was eventually licensed in the US. It is now known to be one of the safest and most effective vaccines available and is administered worldwide. Here are described important factors that contributed to the successful research and licensure of the highly successful VZV vaccine.
Topics: Chickenpox; Chickenpox Vaccine; Drug Approval; Herpes Zoster; Herpes Zoster Vaccine; Herpesvirus 3, Human; Humans; United States; Vaccines, Attenuated
PubMed: 29173081
DOI: 10.1089/vim.2017.0136 -
Vaccine Sep 2021In an effort to control the COVID-19 pandemic, large-scale vaccination is being implemented in various countries using anti-SARS-CoV-2 vaccines based on mRNAs,... (Review)
Review
In an effort to control the COVID-19 pandemic, large-scale vaccination is being implemented in various countries using anti-SARS-CoV-2 vaccines based on mRNAs, adenovirus vectors, and inactivated viruses. However, there are concerns regarding adverse effects, such as the induction of fever attributed to mRNA vaccines and pre-existing immunity against adenovirus vectored vaccines or their possible involvement in the development of thrombosis. The induction of antibodies against the adenovirus vector itself constitutes another hindrance, rendering boosting vaccinations ineffective. Additionally, it has been questioned whether inactivated vaccines that predominantly induce humoral immunity are effective against newly arising variants, as some isolated strains were found to be resistant to the serum from COVID-19-recovered patients. Although the number of vaccinated people is steadily increasing on a global scale, it is still necessary to develop vaccines to address the difficulties and concerns mentioned above. Among the various vaccine modalities, live attenuated vaccines have been considered the most effective, since they closely replicate a natural infection without the burden of the disease. In our attempt to provide an additional option to the repertoire of COVID-19 vaccines, we succeeded in isolating temperature-sensitive strains with unique phenotypes that could serve as seeds for a live attenuated vaccine. In this review article, we summarize the characteristics of the currently approved SARS-CoV-2 vaccines and discuss their advantages and disadvantages. In particular, we focus on the novel temperature-sensitive variants of SARS-CoV-2 that we have recently isolated, and their potential application as live-attenuated vaccines. Based on a thorough evaluation of the different vaccine modalities, we argue that it is important to optimize usage not only based on efficacy, but also on the phases of the pandemic. Our findings can be used to inform vaccination practices and improve global recovery from the COVID-19 pandemic.
Topics: COVID-19; COVID-19 Vaccines; Humans; Pandemics; SARS-CoV-2; Vaccines, Attenuated
PubMed: 34426024
DOI: 10.1016/j.vaccine.2021.08.018 -
FEMS Immunology and Medical Microbiology Apr 2007Francisella tularensis is the causative agent of tularaemia, a disease which occurs naturally in some countries in the northern hemisphere. Recently, there has been a... (Review)
Review
Francisella tularensis is the causative agent of tularaemia, a disease which occurs naturally in some countries in the northern hemisphere. Recently, there has been a high level of interest in devising vaccines against the bacterium because of the potential for it to be used as a bioterrorism agent. Previous human volunteer studies have shown that a strain of F. tularensis [the live vaccine strain (LVS)] that has been attenuated by laboratory passage is effective in humans as a vaccine against airborne disease. However, for a variety of reasons it seems unlikely that the LVS strain will be licensed for use in humans. Against this background there is an effort to devise a licensable vaccine against tularaemia. The prospects for a killed whole-cell subunit of live attenuated vaccine are reviewed. A rationally attenuated mutant seems the most likely route to a new tularaemia vaccine.
Topics: Bacterial Vaccines; Francisella tularensis; Humans; Tularemia; Vaccines, Attenuated; Vaccines, Subunit
PubMed: 17316369
DOI: 10.1111/j.1574-695X.2007.00219.x -
Pathogens and Global Health Jun 2015During the last decade, the chikungunya (CHIKV) virus has expanded its range of activity, conquering new territories and becoming an important global health threat. In... (Review)
Review
During the last decade, the chikungunya (CHIKV) virus has expanded its range of activity, conquering new territories and becoming an important global health threat. In particular, the challenge represented by the recent emergence of CHIKV in the Americas has strengthened the need of a safe and effective vaccine. Although research on vaccines against CHIKV has been slow, a few vaccine candidates have been tested over the years. Inactivated and attenuated vaccine candidates have shown promising results in phase I/II trials, and engineered vaccines have proven to be safe and immunogenic in mouse and/or non-human primate models. Recently, a vaccine based on virus-like particles (VLP) has been successfully tested in a phase I trial. However, large phase I/II controlled trials, which are needed in order to provide evidence of vaccine efficacy, may be planned only under certain conditions. First, they should be conducted during epidemic periods, when a large number of cases occur, in order to ensure an adequate study power. Second, they are expensive and investments returns are not always guaranteed. To overcome this problem, public/private partnership and government support, the identification of target population groups for vaccination and the commitment of donor agencies are key factors for supporting both the development and the availability of vaccines against neglected tropical diseases like chikungunya.
Topics: Animals; Antibodies, Neutralizing; Antibodies, Viral; Chikungunya Fever; Chikungunya virus; Clinical Trials as Topic; Disease Models, Animal; Disease Outbreaks; Financing, Government; Global Health; Humans; Mice; Public-Private Sector Partnerships; Vaccination; Vaccines, Attenuated
PubMed: 25971340
DOI: 10.1179/2047773215Y.0000000017 -
BMJ Clinical Evidence Aug 2007Chickenpox is extremely contagious. Over 90% of unvaccinated people become infected, but infection occurs at different ages in different parts of the world - over 80% of... (Review)
Review
INTRODUCTION
Chickenpox is extremely contagious. Over 90% of unvaccinated people become infected, but infection occurs at different ages in different parts of the world - over 80% of people have been infected by the age of 10 years in the USA, the UK, and Japan, and by the age of 20-30 years in India, South East Asia, and the West Indies.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent chickenpox in healthy adults and children? What are the effects of interventions to prevent chickenpox in children exposed prenatally? What are the effects of interventions to prevent chickenpox in immunocompromised adults and children? What are the effects of treatments for chickenpox in healthy adults and children? What are the effects of treatments for chickenpox in immunocompromised adults and children? We searched: Medline, Embase, The Cochrane Library and other important databases up to March 2007 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS
We found 13 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic review we present information relating to the effectiveness and safety of the following interventions: acyclovir, famciclovir, live attenuated vaccine, valaciclovir, varicella zoster immunoglobulin, and zoster immunoglobulin.
Topics: Chickenpox; Chickenpox Vaccine; Herpes Zoster; Humans; Immunocompromised Host; Incidence; India; Vaccines, Attenuated
PubMed: 19454112
DOI: No ID Found -
Frontiers in Immunology 2022Previous attempts to develop a vaccine against bovine leukemia virus (BLV) have not been successful because of inadequate or short-lived stimulation of all immunity...
Previous attempts to develop a vaccine against bovine leukemia virus (BLV) have not been successful because of inadequate or short-lived stimulation of all immunity components. In this study, we designed an approach based on an attenuated BLV provirus by deleting genes dispensable for infectivity but required for efficient replication. The ability of the vaccine to protect from natural BLV infection was investigated in the context of dairy productive conditions in an endemic region. The attenuated vaccine was tested in a farm in which the prevalence rose from 16.7% in young cattle at the beginning of the study to more than 90% in adult individuals. Sterilizing immunity was obtained in 28 out of 29 vaccinated heifers over a period of 48 months, demonstrating the effectiveness of the vaccine. As indicated by the antiviral antibody titers, the humoral response was slightly reduced compared to wild-type infection. After initial post-vaccination bursts, the proviral loads of the attenuated vaccine remained most frequently undetectable. During the first dairy cycle, proviral DNA was not detected by nested-PCR in milk samples from vaccinated cows. During the second dairy cycle, provirus was sporadically detected in milk of two vaccinated cows. Forty-two calves born from vaccinated cows were negative for proviral DNA but had antiviral antibodies in their peripheral blood. The attenuated strain was not transmitted to sentinels, further supporting the safety of the vaccine. Altogether, these data thus demonstrate that the vaccine against BLV is safe and effective in herd conditions characterized by a very high incidence. This cost-effective approach will thus decrease the prevalence of BLV without modification of production practices. After facing a series of challenges pertaining to effectiveness and biosafety, the vaccine is now available for further large-scale delivery. The different challenges and hurdles that were bypassed may be informative for the development of a vaccine against HTLV-1.
Topics: Animals; Antiviral Agents; Cattle; Enzootic Bovine Leukosis; Female; Leukemia Virus, Bovine; Proviruses; Vaccines, Attenuated
PubMed: 36032174
DOI: 10.3389/fimmu.2022.980514