Biological Sciences
Smallpox and Measles
Smallpox and measles are highly contagious viral diseases that have historically caused significant morbidity and mortality. Smallpox, caused by the variola virus, was declared eradicated in 1980 due to a successful global vaccination campaign. Measles, caused by the measles virus, remains a concern, particularly in areas with low vaccination rates, and can lead to severe complications.
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12 Key excerpts on "Smallpox and Measles"
- Jerrold B. Leikin, Robin B. McFee, Robert Kerscher, Jerrold B. Leikin, Robin B. McFee, Robert Kerscher(Authors)
- 2007(Publication Date)
- CRC Press(Publisher)
Smallpox infections have been recognized as far back as ancient Egypt, affecting pharaohs and peasants. Unlike decades ago when smallpox was a naturally occurring infection, concerns are emerging that smallpox may become intentionally spread as a bioweapon. Intelligence sources suggest Iraq and other terrorist-friendly nations may have access to or already weaponized Variola. Rumors persist that scientists in the former Soviet Union were trying to develop an Ebola/ Variola hybrid virus. Smallpox is an Orthopox virus, which consists of the infectious agents that cause camelpox, smallpox, monkeypox, and cowpox. Immunity to one member of this family confers protection against others, hence the use of vaccinia (cowpox) virus to immunize against Variola. Vaccinia is a virus with minimal pathogenicity except in immune-compromised patients. Smallpox is a painful, disabling, febrile disease. Variola occurs as primarily two strains -variola major (smallpox) and the less pathological version variola minor -which causes a milder febrile rash, and is sometimes referred to as alastrim. Smallpox presents a particularly serious risk because of a high case-fatality rate estimated at 30 percent to 50 percent depending upon the strain, naive vaccine status of the exposed population and inconsistent availability of appropriate healthcare to prevent secondary bacterial infection. It is a highly pathogenic virus; it is estimated B 10-100 smallpox virions is necessary to cause human illness! Bioterrorism experts consider smallpox to be a significant threat because it is relatively easy to produce once starting material is obtained, the aerosol infectivity -contagiousness, widespread susceptibility of nonimmunized or under-immunized populations. Contagion results from transmitting virus in airborne droplets or by contact with lesions. Primary portal of entry is the respiratory tract so population density, overcrowding, as well as immune status affect the extent of spread.
eBook - PDF- Rachel L. Chin, Bradley W. Frazee, Zlatan Coralic(Authors)
- 2018(Publication Date)
- Cambridge University Press(Publisher)
498 Chapter 498 Outline Introduction 498 Epidemiology 498 Reservoirs 498 Mode of Transmission 498 Worldwide Occurrence 498 Occurrence in the United States 498 Smallpox as a Biological Weapon 499 Clinical Features 499 Variola Major 500 Variola Minor 500 Differential Diagnosis 500 Laboratory and Radiographic Findings 502 Treatment and Prophylaxis 502 Treatment 502 Immunity from Prior Vaccination 503 Post-Exposure Prophylaxis 503 Vaccine Supply, Administration, and Recommendations 503 Vaccine Contraindications and Complications 503 Complications and Admission Criteria 504 Infection Control 504 Decontamination 504 Pearls and Pitfalls 504 References 504 Additional Readings 505 Smallpox David M. Stier, Mary P. Mercer, and Rachel L. Chin 69 Introduction Smallpox is caused by variola viruses, which are large, envel- oped, DNA viruses of the Poxvirus family and the Orthopoxvirus genus. Variola major strains cause three forms of disease (ordi- nary, flat type, and hemorrhagic), whereas variola minor strains cause a less severe form of smallpox. Vaccination with vaccinia virus, another member of the Orthopoxvirus genus, protects humans against smallpox because of the high antibody cross- neutralization between orthopoxviruses. Historically, smallpox was a significant and deadly disease, with a case-fatality rate of 30% or more among unvaccinated persons. However, the virus was declared eradicated worldwide in 1980, following an extensive vaccination campaign led by the World Health Organization (WHO). Nevertheless, because of its lethality and the absence of specific therapy, the Working Group for Civilian Biodefense considers smallpox a dangerous potential biological weapon. Of the potential ways in which smallpox could be used as a biological weapon, an aerosol release is expected to have the most severe medical and public health outcomes because of the virus’s stability in aerosol form, low infectious dose, and high rate of secondary transmission.
eBook - PDFGerm Wars
The Politics of Microbes and America's Landscape of Fear
- Melanie Armstrong(Author)
- 2017(Publication Date)
- University of California Press(Publisher)
Flu-like symptoms emerge within two weeks of infec-tion, and then small lesions appear in the mouth, growing and rupturing, spewing the virus into the body through the saliva. After this surge of infection, the characteristic rash emerges, with pustules—smaller than 34 | “Smallpox Is Dead” those of syphilis—developing during a final phase, descriptively named “ordinary,” “flat,” “modified,” or “hemorrhagic.” Lifelong scars mark bodies that have hosted Variola major and survived. Jessica Stern describes bioterror as a “dreaded risk” because its depiction of the future hinges on experiences of infection that evoke visceral horror and cannot be avoided or expelled. 6 Smallpox produces just such a reaction. However, the worldwide campaign to eradicate smallpox and the integration of smallpox prevention into the public health economy have produced another way of knowing smallpox, in terms of social control and the management of collective life. As mod-ern science practice revives smallpox with narratives of a transgenic mutation of the virus that could escape control, the primal experiences of disgust rise again. Smallpox’s origin story narrates both the benefits and the conse-quences of human intimacy with nonhuman nature. Domestication brought livestock into human societies, putting people in physical con-tact with mammals and birds and their accompanying microbes. Crowd-ing among humans and animals then enabled the disease to spread. 7 This narrative of infectious disease emerging as a consequence of living too closely with animals persists today in discourses about avian flu in Asia or swine flu in Mexico. Biologists and historians theorize that con-tinued interspecies interactions over time build a population’s collective immunity, making individual bodies less susceptible to disease and inscribing in them a genetic code that is transmitted to successive gen-erations for the survival of the population.
eBook - PDF- Ronald W. Ellis(Author)
- 2001(Publication Date)
- CRC Press(Publisher)
Measles Vaccines Measles virus, member of the paramyxovirus family, is the most contagious viral pathogen known to man. Before the advent of effective vaccines, essentially the entire birth cohort was infected by a very early age. Although measles is normally a self-limiting disease in healthy subjects, the rash, cough and high fever make it an extremely unpleasant experience. The au thor remembers vividly having measles at the age of five and being quite miserable. Measles is a particularly nasty disease for two reasons. First, measles virus is immunosuppressive, and this results in a variety of opportunistic infections. Natural measles infection also has a group of relatively rare but serious long-term sequelae including measles inclusion body encephalitis and subacute sclerosing panencephalitis. The pathogenesis of measles infection and its compli cations is the subject of a recent review by Schneider-Schaulies and ter Meulen .72 Early vaccine development began in the 1930s with an inactivated virus strategy which was abandoned due to short-lived immunogenicity and the appearance of atypical measles disease in vaccinees exposed to wild-type virus .73' 76 This phenomenon is attributed to inappro priate priming of C D 4 T-cell responses typical of an Arthus reaction .77 Attenuation of Measles Viruses Current live attenuated measles vaccines can be traced to the isolation of measles virus by Enders and Peebles in 1954.78 This virus was attenuated by Enders and co-workers ,79 by passage in human kidney and human amnion cells to yield the Edmonston-Enders strain (Edmonston was the surname of the child from whom the virus was isolated). This strain went on to become the parent of several live attenuated measles vaccines developed in the United States, Europe, Russia, Czechoslovakia and Japan.
- Dongyou Liu(Author)
- 2014(Publication Date)
- CRC Press(Publisher)
We cannot deny that bioterrorism is a threat. Nor can we deny the horrors that would occur if variola virus were used as a bioterrorist weapon. This chapter will start with a review of the virology of variola virus and the past epidemics it caused. This will be followed by a description of the program of smallpox eradi-cation—the first successful human effort in history of public health to actually eradicate a human disease. Next, there will be a discussion on how to deal with the threat of a purposeful reintroduction of smallpox using the experience and lessons learned from the previous smallpox control and eradication efforts. Last, it will stress the indispensable role of the WHO for all phases of planning and implementation of an effective response. A smallpox bioterrorist introduction will not be a single-country issue. It will be a global issue. Thus, WHO will have to continue to be front and center on this issue. 21.2 CLASSIFICATION AND MORPHOLOGY OF SMALLPOX VIRUS Smallpox virus (variola virus) causes a systematic infec-tion in man. It belongs to the genus Orthopox that includes vaccinia, cowpox, monkeypox, camelpox, and others. It is a DNA virus having the dimensions of 300 × 250 × 200 nm. It is brick shaped and easy to identify being morphologically different from other viruses causing exanthema in man such as measles and varicella. Infection by the most common smallpox virus (known as variola major) carried a 30%–50% case fatality, whereas a group of smallpox viruses known as variola minor or alastrim carried a fatality rate closer to 1%. In addition, there was also variola intermediate carrying a case fatality between minor and major. Although the genome of the variola major is known and published [2], the genetic understanding of the reasons for the different clinical expres-sion is not well understood. Clinically, smallpox is generally very distinct and easy to diagnose.
eBook - PDF- Patricia Clayton-LeVasseur(Author)
- 2022(Publication Date)
- Greenwood(Publisher)
15 2 The History of Measles The disease of measles, also known as rubeola, has been a part of human history for thousands of years. Initially, Smallpox and Measles were consid- ered the same illness, but Muhammad ibn Zakariya al-Razi (865–925 CE), or Rhazes, a Persian doctor, discovered characteristics of measles that sep- arated the two infections. His discoveries earned him the title of the father of pediatrics. This highly contagious disease measles stems from the rin- derpest virus, which originated from cattle. Immunologically naïve popu- lations have been reduced and—in some cases—eradicated by measles because it is a persistent endemic disease for many geographical areas and among some defined peoples. This disease has had the potential of being destroyed with a practical and consistent worldwide vaccination agenda. Exposure to measles was considered a regular life event for children until relatively recent times, the 1960s. The measles vaccination crusade of 1963 substantially reduced infection rates, and measles was virtually eliminated from the United States by 2000. However, global anti-vaccination cam- paigns have resulted in a resurgence of this disease. CATTLE HERDERS IN THE MIDDLE EAST: THE ORIGINS OF MEASLES Scientists speculate that measles infections date back to the Epipaleo- lithic period (20,000–10,000 BCE), the middle portion of the Stone Age 16 What You Need to Know about Measles when people survived as hunter-gatherers. This phase of nomadic activity came to a gradual end as the weather changed to colder and drier condi- tions. Humankind transitioned to agriculture and domesticating herd ani- mals, such as goats, sheep, and cattle. The domestication of herd animals forced people to live in settled communities with close proximity to enclosed pastures to protect livestock from predators. This practice offered safety for the animals but exposed the human population to animal- specific diseases and viruses.
eBook - PDFThe Savage Wars of Peace
England, Japan and the Malthusian Trap
- A. Macfarlane(Author)
- 2002(Publication Date)
- Palgrave Macmillan(Publisher)
Only in the case of smallpox was some early action possible. Yet, as we shall see, while human 16 Air-borne Diseases: Smallpox, Measles and Tuberculosis 1 Burnett, Infectious, 107,109. 2 Schofield et al. (eds), Decline, 171. 3 Burnett, Infectious, 109. 286 In the Air beings were largely unable to deal with these threats directly, the cumulative effect of the reduction of malnutrition and increasing general health may well help to explain what has hitherto been the inexplicable decline of some of these diseases. Here I will consider just three of the most serious of these droplet borne diseases, smallpox, measles and tuberculosis. 4 Smallpox (variola) was a major scourge of human populations until the nineteenth century. It was a particularly painful and deadly disease. Apart from its gruesome symptoms, smallpox is significant both for its high case mortality and because of its ability to survive outside the human host. ‘Leading the pack is the smallpox virus which kills one in ten and can survive for more than a decade outside of the host.’ 5 It has been suggested that ‘The virus first appeared in Europe before the tenth century where it probably established itself as a minor flu-like nuisance.’ 6 Something happened to change this in the sixteenth and seventeenth centuries and it grew increa- singly virulent, decimating parts of the New World as well as the Old. 7 The fluctuations could be quite abrupt. We are told that ‘Smallpox mortality itself evidently rose sharply in the early decades of the eighteenth century and fell again after 1750.’ 8 As Malthus observed, ‘The small-pox is certainly one of the channels, and a very broad one, which nature has opened for the last thousand years to keep down the population to the level of the means of subsistence.’ 9 Creighton provided a useful general account of smallpox. He believed that the earliest reliable references to it in England occurred in a letter of 1514.
No longer available |Learn more- (Author)
- 2014(Publication Date)
- University Publications(Publisher)
The disease killed an estimated 400,000 Europeans per year during the closing years of the 18th century (including five reigning monarchs), and was responsible for a third of all blindness. Of all those infected, 20–60%—and over 80% of infected children—died from the disease. Smallpox was responsible for an estimated 300–500 million deaths during the 20th century. As recently as 1967, the World Health Organization (WHO) estimated that 15 million people contracted the disease and that two million died in that year. After vaccination campaigns throughout the 19th and 20th centuries, the WHO certified the eradication of smallpox in 1979. Smallpox is one of the two infectious diseases to have been eradicated, the other being rinderpest, which was unofficially declared eradicated in 2010. Classification There are two clinical forms of smallpox. Variola major is the severe and most common form, with a more extensive rash and higher fever. Variola minor is a less common presentation, and a much less severe disease, with historical death rates of 1% or less. Subclinical (asymptomatic) infections with variola virus have been noted, but are not common. In addition, a form called variola sine eruptione (smallpox without rash) is seen generally in vaccinated persons. This form is marked by a fever that occurs after the usual incubation period and can be confirmed only by antibody studies or, rarely, by virus isolation. ________________________ WORLD TECHNOLOGIES ________________________ Child showing rash due to ordinary-type smallpox (variola major) Signs and symptoms The incubation period between contraction and the first obvious symptoms of the disease is around 12 days. Once inhaled, variola major virus invades the oropharyngeal (mouth and throat) or the respiratory mucosa, migrates to regional lymph nodes, and begins to multiply.
eBook - PDFPerspectives in Medical Virology, vol. 1
Perspectives in Medical Virology, vol. 1
- Brian Evans(Author)
- 2003(Publication Date)
- Elsevier(Publisher)
We have noted above the serious morbidity and also mortality caused by measles. Indeed, estimates of 900 000 deaths annually in underdeveloped countries caused by measles are accept- ed as reasonably accurate. Hinman (1982) has compared and contrasted measles and smallpox as regards several factors which are relevant to worldwide eradication (Table 8.29). Note that measles shares six of the favourable characteristics with smallpox. Three important differing factors are that smallpox was of lower infecti- vity than measles and so did not spread so rapidly through susceptible populations. therefore smallpox was sometimes eradicated from areas where overall immuniza- tion rates were low. In fact, a containment policy was used whereby once a smallpox case was discovered all contacts in the immediate area were vaccinated (see Chapter 15). In contrast, we know that measles may still be transmitted in communities with immunization levels of > 90%. but on the other hand, it is not clear if measles can persisr indefinitely in these conditions of strong immunity pressure. A crucial re- maining factor which could strongly influence such a campaign is the amount of international support for a global immunization campaign against measles. The an- swer here may be ambiguous and is not helped by countries where immunization rates are low (Table 8.30). A satisfactory result in the USA, USSR or DDR however, would most likely stimulate international interest and already, another country, Canada, is consider- ing a national programme of measles eradication. It is very worthwhile then to ana- lyze the experience in one of these countries (USA) which hopefully will be repeated TABLE 8.29.
- J. Youde(Author)
- 2010(Publication Date)
- Palgrave Macmillan(Publisher)
These fears fed rumors about malicious intents behind the eradication campaign. To tell the story of smallpox’s eradication, we need to first under- stand the disease’s etiology and history. This chapter will trace the development of, resistance to, and ultimate success of the smallpox eradication program. The eradication effort succeeded both because of some unique characteristics of the virus and the special emphasis placed on creating a useful and accurate surveillance program. We will also see why some groups and communities actively resisted this surveillance. Finally, the chapter will briefly discuss the resurgence of interest in vaccinating populations against smallpox and the biopo- litical fears such programs provoke. SIGNS AND S YMPTOMS OF SMALLPOX They called it “the speckled monster.” It seemingly struck at random, killing young and old, rich and poor, male and female. It killed more than one-quarter of those infected. Survivors bore disfiguring scars for the rest of their lives. Smallpox-inspired levels of dread and mor- tality unique among infectious diseases thanks to its randomness and its virulence. A medical textbook published in 1888 described the disease thus: “Smallpox, by reason of the malignant nature of its poi- son, and the general susceptibility to it of individuals of all ages, races, classes, and conditions, is the most loathsome and fatal disease known to man.” 1 S M A L L P OX : D E F E AT I NG T H E S C OU RG E 65 At its most basic level, smallpox is a viral infection. Exposure to the variola virus puts a person at risk of contracting smallpox. Exposure generally comes from direct, prolonged face-to-face contact with an infected person. Direct contact with infected bodily fluids or con- taminated bedding can also cause infection. In some instances, small- pox has traveled through the air in enclosed spaces like hospitals.
eBook - ePub- Irwin W. Sherman(Author)
- 2007(Publication Date)
- ASM Press(Publisher)
The cause of smallpox is a virus, one of the largest of the viruses; with proper illumination it can actually be seen under a light microscope. However, much of its detailed structure can be visualized only by using the electron microscope. The outer surface (capsid) of the smallpox virus resembles the facets of a diamond, and its inner, dumbbell-shaped core contains the genetic material, double-stranded DNA. The virus has about 200 genes, 35 of which are thought to be involved in virulence.Most commonly the smallpox virus enters the body through droplet infection by inhalation. However, it can be transmitted by direct contact or through contaminated fomites (inanimate objects) such as clothing, bedding, blankets, and dust. The infectious material from the pustules can remain infectious for months. The virus multiplies in the mucous membranes of the mouth and nose. During the first week of infection there is no sign of illness; however, the virus can be spread by coughing or by nasal mucus at this time. The virus moves on to the lymph nodes and then to the internal organs via the bloodstream. Once there, it multiplies again. It then reenters the bloodstream. Around the ninth day the first symptoms appear: headache, fever, chills, nausea, muscle ache, and sometimes convulsions. The person feels quite ill. A few days later a characteristic rash appears. The individual is infectious a day before the rash appears and until all the scabs have fallen off. Many infected persons die a few days or a week after the rash appears. Destruction of the sebaceous (oil) glands of the skin leaves permanent craterlike scars in the skin, known as pockmarks.There are two varieties of the smallpox (variola) virus: major and minor. They can be distinguished by differences in their genes. Variola major, the deadlier form, frequently killed up to 25% of its victims, although in naïve populations such as the Amerindians the fatality rate could exceed 50%. Variola minor,
eBook - PDFCoordinating Global Health Policy Responses
From HIV/AIDS to Ebola and Beyond
- Annamarie Bindenagel Šehovi?, Annamarie Bindenagel Šehovi?, Annamarie Bindenagel Šehovi?, Annamarie Bindenagel Šehovi?, Annamarie Bindenagel Šehović(Authors)
- 2017(Publication Date)
- Palgrave Macmillan(Publisher)
CHAPTER 2 Measles Abstract Chapter 2 delves into the politics and policy surrounding measles. It explores the impact of this old but recurring disease, dispel- ling myths around its description as a ‘childhood disease’. It tallies its costs, both in terms of disease toll on the infected individual as well as of the financial burden of care at the familial and national levels. This chapter uses this relationship between individual infection and broader transactional costs, to explore more broadly the relationship between individual rights and state (international) requirements, notably of immunizations. Keywords Measles Á Herd immunity Á Immunization Á Vaccination Á Reactance MEASLES: AN OVERVIEW Measles, which should incite fear, too often in the Western world, does not. The consequences can be dire. Measles is a virus of the Morbillivirus family. The virus most likely emerged in the 11th and 12th centuries. It is derived from mutations in rinderpest virus (RPV), meaning it is a zoonosis: a disease that jumped the animal–human barrier to infect human beings. © The Author(s) 2017 A. Bindenagel Šehović, Coordinating Global Health Policy Responses, DOI 10.1007/978-3-319-52006-3_2 25 The original territorial emergence of measles appears to be unknown, as it has spread throughout the entire globe. 1 As recently as 1980, the WHO recorded 2.6 million measles-related deaths per year. 2 The latest WHO data, from 2015, estimates 134,200 measles deaths globally—about 367 deaths every day or more than 15 deaths every hour. 3 The WHO does not record the number of infections, which are always higher than that of deaths by a significant factor. This leads to the first point of confusion and contention around measles: that since most infections do not lead to death, the disease does not pose a threat. Yet this false understanding represents both biological and political error.
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