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Canadian Medical Association Journal Oct 1962Smallpox has been known as a disease of man since the earliest times. However, its severity increased greatly during the eighteenth century, stimulating physicians and...
Smallpox has been known as a disease of man since the earliest times. However, its severity increased greatly during the eighteenth century, stimulating physicians and others to find methods of protection against it. Variolation (the inoculation of smallpox material into the skin) was tried, and for a while found general approval, although its practice was not without danger. In 1796, Edward Jenner began his investigations into the use of cow-pox material (vaccination) as a prophylactic against smallpox, and later showed that vaccination could confer protection. Although vaccination centres were first set up in Canada early in the nineteenth century, the disease on occasion assumed epidemic proportions, such as occurred in Montreal in 1885. Sporadic outbreaks have occurred since then, including the recent case in Toronto. From the public health point of view, maintenance of a high level of immunity to smallpox throughout the general population is necessary if serious epidemics are to be avoided.
Topics: Animals; Canada; Cowpox; Disease Outbreaks; Epidemics; History of Medicine; Humans; Male; Physicians; Smallpox; Smallpox Vaccine; Vaccination; Variola virus
PubMed: 14016000
DOI: No ID Found -
Expert Review of Vaccines Sep 2021The Development of the SARS-CoV-2 virus vaccine and its update on an ongoing pandemic is the first subject of the world health agenda.
INTRODUCTION
The Development of the SARS-CoV-2 virus vaccine and its update on an ongoing pandemic is the first subject of the world health agenda.
AREAS COVERED
First, we will scrutinize the biological features of the measles virus (MV), variola virus (smallpox virus), influenza virus, and their vaccines to compare them with the SARS-CoV-2 virus and vaccine. Next, we will discuss the statistical details of measuring the effectiveness of an improved vaccine.
EXPERT OPINION
Amidst the pandemic, we ought to acknowledge our prior experiences with respiratory viruses and vaccines. In the planning stage of observational Phase-III vaccine effectiveness studies, the sample size, sampling method, statistical model, and selection of variables are crucial in obtaining high-quality and valid results.
Topics: COVID-19; COVID-19 Vaccines; Humans; Immunity, Cellular; Influenza Vaccines; Mass Vaccination; Measles virus; Measles-Mumps-Rubella Vaccine; Orthomyxoviridae; SARS-CoV-2; Smallpox Vaccine; Vaccination; Vaccines, Attenuated; Variola virus
PubMed: 34365880
DOI: 10.1080/14760584.2021.1965884 -
Viruses Mar 2015The question of the origin of smallpox, one of the major menaces to humankind, is a constant concern for the scientific community. Smallpox is caused by the agent... (Review)
Review
The question of the origin of smallpox, one of the major menaces to humankind, is a constant concern for the scientific community. Smallpox is caused by the agent referred to as the variola virus (VARV), which belongs to the genus Orthopoxvirus. In the last century, smallpox was declared eradicated from the human community; however, the mechanisms responsible for the emergence of new dangerous pathogens have yet to be unraveled. Evolutionary analyses of the molecular biological genomic data of various orthopoxviruses, involving a wide range of epidemiological and historical information about smallpox, have made it possible to date the emergence of VARV. Comparisons of the VARV genome to the genomes of the most closely related orthopoxviruses and the examination of the distribution their natural hosts' ranges suggest that VARV emerged 3000 to 4000 years ago in the east of the African continent. The VARV evolution rate has been estimated to be approximately 2 × 10-6 substitutions/site/year for the central conserved genomic region and 4 × 10-6 substitutions/site/year for the synonymous substitutions in the genome. Presumably, the introduction of camels to Africa and the concurrent changes to the climate were the particular factors that triggered the divergent evolution of a cowpox-like ancestral virus and thereby led to the emergence of VARV.
Topics: Africa, Eastern; Evolution, Molecular; Humans; Mutation Rate; Variola virus
PubMed: 25763864
DOI: 10.3390/v7031100 -
Antimicrobial Agents and Chemotherapy Mar 2020Forty years after the last endemic smallpox case, variola virus (VARV) is still considered a major threat to humans due to its possible use as a bioterrorism agent. For... (Review)
Review
Forty years after the last endemic smallpox case, variola virus (VARV) is still considered a major threat to humans due to its possible use as a bioterrorism agent. For many years, the risk of disease reemergence was thought to solely be through deliberate misuse of VARV strains kept in clandestine laboratories. However, recent experiments using synthetic biology have proven the feasibility of recreating a poxvirus , implying that VARV could, in theory, be resurrected. Because of this new perspective, the WHO Advisory Committee on VARV Research released new recommendations concerning research on poxviruses that strongly encourages pursuing the development of new antiviral drugs against orthopoxviruses. In 2018, the U.S. FDA advised in favor of two molecules for smallpox treatment, tecovirimat and brincidofovir. This review highlights the difficulties to develop new drugs targeting an eradicated disease, especially as it requires working under the FDA "animal efficacy rule" with the few, and imperfect, animal models available.
Topics: Animals; Antiviral Agents; Benzamides; Biological Warfare Agents; Biomedical Research; Cytosine; Disease Models, Animal; Drug Discovery; Isoindoles; Organophosphonates; Smallpox; Variola virus
PubMed: 31932370
DOI: 10.1128/AAC.01683-19 -
The Egyptian Journal of Internal... 2022The famed variola (smallpox) virus and the monkeypox virus (MPXV) are closely related, and MPXV causes a milder form of febrile rash disease in people. Human monkeypox... (Review)
Review
The famed variola (smallpox) virus and the monkeypox virus (MPXV) are closely related, and MPXV causes a milder form of febrile rash disease in people. Human monkeypox was mostly an uncommon zoonotic illness that was restricted to West and Central African wooded areas in the twentieth century. The global population's smallpox vaccine-induced immunity, however, has started to decrease as the number of cases and the geographic breadth have both increased significantly in this century. Several countries have seen human monkeypox outbreaks since May 2022. A possible shift in the monkeypox transmission pattern that might represent a bigger worldwide danger is raised by the atypical nature of these outbreaks, which are characterized by their high-case numbers and absence of ties to endemic countries. Here, we explore a wide range of MPXV biology topics.
PubMed: 36530575
DOI: 10.1186/s43162-022-00174-0 -
BMJ (Clinical Research Ed.) Apr 2007Other viruses pose greater public health threats, so isn't it time to move on?
Other viruses pose greater public health threats, so isn't it time to move on?
Topics: Biological Specimen Banks; Ethics, Research; Health Policy; Humans; Smallpox Vaccine; Variola virus; Virology
PubMed: 17431234
DOI: 10.1136/bmj.39177.580729.BE -
Viruses Aug 2023Smallpox was eradicated in less than 200 years after Edward Jenner's practice of cowpox variolation in 1796. The forty-three years of us living free of smallpox,... (Review)
Review
Smallpox was eradicated in less than 200 years after Edward Jenner's practice of cowpox variolation in 1796. The forty-three years of us living free of smallpox, beginning in 1979, never truly separated us from poxviruses. The recent outbreak of monkeypox in May 2022 might well warn us of the necessity of keeping up both the scientific research and public awareness of poxviruses. One of them in particular, the vaccinia virus (VACV), has been extensively studied as a vector given its broad host range, extraordinary thermal stability, and exceptional immunogenicity. Unceasing fundamental biological research on VACV provides us with a better understanding of its genetic elements, involvement in cellular signaling pathways, and modulation of host immune responses. This enables the rational design of safer and more efficacious next-generation vectors. To address the new technological advancement within the past decade in VACV research, this review covers the studies of viral immunomodulatory genes, modifications in commonly used vectors, novel mechanisms for rapid generation and purification of recombinant virus, and several other innovative approaches to studying its biology.
Topics: Humans; Smallpox; Vaccinia virus; Variola virus; Poxviridae; Orthopoxvirus
PubMed: 37632084
DOI: 10.3390/v15081742 -
Current Opinion in Immunology Jun 2009In spite of the eradication of smallpox over 30 years ago; orthopox viruses such as smallpox and monkeypox remain serious public health threats both through the... (Review)
Review
In spite of the eradication of smallpox over 30 years ago; orthopox viruses such as smallpox and monkeypox remain serious public health threats both through the possibility of bioterrorism and the intentional release of smallpox and through natural outbreaks of emerging infectious diseases such as monkeypox. The eradication effort was largely made possible by the availability of an effective vaccine based on the immunologically cross-protective vaccinia virus. Although the concept of vaccination dates back to the late 1800s with Edward Jenner, it is only in the past decade that modern immunologic tools have been applied toward deciphering poxvirus immunity. Smallpox vaccines containing vaccinia virus elicit strong humoral and cellular immune responses that confer cross-protective immunity against variola virus for decades after immunization. Recent studies have focused on: establishing the longevity of poxvirus-specific immunity, defining key immune epitopes targeted by T and B cells, developing subunit-based vaccines, and developing genotypic and phenotypic immune response profiles that predict either vaccine response or adverse events following immunization.
Topics: B-Lymphocytes; Humans; Models, Immunological; Signal Transduction; Smallpox; Smallpox Vaccine; T-Lymphocytes, Cytotoxic; Vaccinia virus; Variola virus; Virus Replication
PubMed: 19524427
DOI: 10.1016/j.coi.2009.04.004 -
Viruses Aug 2022In the late 1970s, global vaccination programs resulted in the eradication of smallpox. The Monkeypox virus (MPXV), which is closely related to the smallpox-inducing... (Review)
Review
In the late 1970s, global vaccination programs resulted in the eradication of smallpox. The Monkeypox virus (MPXV), which is closely related to the smallpox-inducing variola virus, was previously endemic only in Sub-Saharan Africa but is currently spreading worldwide. Only older people who have been vaccinated against smallpox are expected to be sufficiently protected against poxviruses. Here I will summarize current knowledge about the virus, the disease caused by MPXV infections, and strategies to limit its spread.
Topics: Aged; Humans; Longitudinal Studies; Mpox (monkeypox); Monkeypox virus; Smallpox; Variola virus
PubMed: 36146681
DOI: 10.3390/v14091874 -
Immunological Reviews Jan 2011The eradication of smallpox, one of the great triumphs of medicine, was accomplished through the prophylactic administration of live vaccinia virus, a comparatively... (Review)
Review
The eradication of smallpox, one of the great triumphs of medicine, was accomplished through the prophylactic administration of live vaccinia virus, a comparatively benign relative of variola virus, the causative agent of smallpox. Nevertheless, recent fears that variola virus may be used as a biological weapon together with the present susceptibility of unimmunized populations have spurred the development of new-generation vaccines that are safer than the original and can be produced by modern methods. Predicting the efficacy of such vaccines in the absence of human smallpox, however, depends on understanding the correlates of protection. This review outlines the biology of poxviruses with particular relevance to vaccine development, describes protein targets of humoral and cellular immunity, compares animal models of orthopoxvirus disease with human smallpox, and considers the status of second- and third-generation smallpox vaccines.
Topics: Animals; Antibodies, Viral; Biological Warfare Agents; Disease Models, Animal; Gene Expression Regulation, Viral; Humans; Mice; Orthopoxvirus; Poxviridae Infections; Smallpox; Smallpox Vaccine; Vaccines; Vaccinia virus; Variola virus
PubMed: 21198662
DOI: 10.1111/j.1600-065X.2010.00975.x