Smallpox is an infectious disease caused by one of two viral variants, Variola major and Variola minor . The last natural case diagnosed in October 1977 and the World Health Organization (WHO) certified the global eradication of the disease in 1980. The risk of death after contracting the disease was about 30%, with a higher rate among infants. Often those who survive have extensive scar tissue on their skin and some are left blind.
The initial symptoms of the disease include fever and vomiting. This is then followed by the formation of cuts in the mouth and skin rashes. For several days, the skin rash turns into a fluid filled with a dent in the middle. The lumps then scab and fall off the marks. The disease is used to spread among people or through contaminated objects. Prevention is with smallpox vaccine. Once the disease has developed certain antiviral drugs may help.
The origin of smallpox is unknown. The earliest evidence of this disease dates from the 3rd century BC on Egyptian mummies. This disease has historically occurred in outbreaks. In 18th-century Europe an estimated 400,000 people per year die from the disease, and a third of cases lead to blindness. This death included at least five ruling kings. In the 20th century it was estimated that smallpox resulted in the deaths of 300-500 million. Most recently in 1967, 15 million cases occurred within a year.
Edward Jenner discovered in 1798 that vaccination could prevent smallpox. In 1967, the World Health Organization intensified efforts to eliminate the disease. Smallpox is one of two infectious diseases that have been eradicated, others are rinderpest in 2011. The term "smallpox" was first used in England in the 15th century to distinguish the disease from syphilis, which came to be known as the "bigpox".. Other historical names for the disease include smallpox, speckled monster, and red plague.
Video Smallpox
Classification
There are two clinical forms of smallpox. Variola major is the most severe and most common form, with a wider rash and a high fever. Variola minor is a less common presentation, and a much milder disease, with a historical mortality of 1 percent or less. Subclinical (asymptomatic) infections with variola virus are noted but are not common. In addition, a form called variola sine eruptione (smallpox without rash) is seen commonly in the vaccinated person. This form is characterized by fever that occurs after a typical incubation period and can only be confirmed by antibody studies or, rarely, by viral isolation.
Maps Smallpox
Signs and symptoms
The incubation period between contractions and the first obvious symptoms of the disease is about 12 days. Once inhaled, the main virus of the variola attacks the oropharyngeal (mouth and throat) or respiratory mucosa, migrates to the regional lymph nodes, and begins to multiply. In the early growth phase the virus seems to move from cell to cell, but around the 12th day, lysis of many infected cells occurs and the virus is found in the bloodstream in large quantities (this is called viremia ), and waves both multiplication occurs in the spleen, bone marrow, and lymph nodes.
Early symptoms are similar to other viral diseases such as influenza and common cold: fever of at least 38.3 ° C (101 ° F), muscle aches, malaise, headache and prostration. Since the digestive tract is commonly involved, nausea and vomiting and back pain are common. The prodrome, or preeruptive stage, usually lasts 2-4 days. On the 12-15th day the first lesion is seen - small reddish spots called enanthem - appear on the mucous membranes of the mouth, tongue, palate, and throat, and the temperature falls close to normal. The lesion rapidly enlarges and bursts, releasing large amounts of virus into the saliva.
Specialized smallpox virus attacks the skin cells, causing characteristic acne (called macules) associated with the disease. The rash occurs on the skin 24 to 48 hours after the lesion on the mucous membrane appears. Usually macules first appear on the forehead, then rapidly spread throughout the face, the proximal extremity, the stem, and finally to the distal part of the extremities. The process is no more than 24 to 36 hours, after which no new lesions appear. At this point, large variola infections can take several very different programs, producing four types of smallpox under the Rao classification: normal, modified, malignant (or flat), and hemorrhagic. Historically, smallpox had an overall mortality rate of around 30 percent; Malignant and hemorrhagic forms are usually fatal.
Ordinary
Ninety percent or more cases of smallpox among unvaccinated people are the usual type. In this form of the disease, on the second day of the rash, the macula becomes a raised papula . On the third or fourth day, the papules are filled with opalescent fluid to become vesicles . This fluid becomes opaque and turbid within 24-48 hours, giving them the appearance of pustules; called pustules filled with tissue debris, not pus.
On the sixth or seventh day, all the skin lesions become pustules. Between seven and ten days, the pustula matures and reaches its maximum size. Pustules increase sharply, usually round, tense, and hard to touch. Pustules are deeply ingrained in the dermis, giving them the feel of small beads on the skin. The liquid slowly leaks out of the pustules, and by the end of the week the two pustules deflate, and begin to dry, forming crusts (or scabs). On the day 16-20 Scab has formed over all lesions, which have begun to peel, leaving the scars lost.
Usually smallpox generally produces a discrete rash, in which the pustules protrude on the skin separately. The distribution of the most dense rash on the face; more dense to the extremities than in the trunk; and in the extremities, more densely distal than proximal. The palms and soles are involved in most cases. Occasionally, blisters combine into sheets, forming a confluent rash, which begins to remove the outer layer of skin from the underlying flesh. Patients with confluent pox often remain ill even after scab forms in all lesions. In one case series, the case-fatality rate in the confluent cacar was 62 percent.
Modified
Referring to the character of the eruption and its speed of development, smallpox modification occurs mostly in people who have been vaccinated before. In this form prodromal disease still occurs but may be less severe than in the usual type. Usually there is no fever during the evolution of the rash. Skin lesions tend to be less and evolve faster, more superficially, and may not exhibit more typical characteristics of smallpox uniforms. Chickenpox modified rarely, if ever, fatal. The shape of the major variola is more easily confused with chickenpox.
Malignant
In malignant-type pox (also called smallpox) the lesion remains almost flat with the skin at the time when the vesicles arise in the usual type. It is not known why some people develop this type. Historically, it covers 5-10 percent of cases, and the majority (72 percent) are children. Malignant pox is accompanied by a severe prodromal phase lasting 3-4 days, prolonged high fever, and severe toxemia symptoms. The rash on the tongue and the ceiling is very wide. The skin lesions mature slowly and on the seventh or eighth day they become flat and appear buried in the skin. Unlike the common type of smallpox, the vesicles contain small amounts of fluid, are soft and smooth to the touch, and may contain bleeding. Malignant pox is almost always fatal.
Hemorrhag
Hemorrhagic pox is a severe form with extensive bleeding to the skin, mucous membranes, and gastrointestinal tract. This form develops in about 2 percent of infections and mostly occurs in adults. In hemorrhagic pox the skin does not blister, but remains smooth. Conversely, bleeding occurs under the skin, making it look scorched and black, then this form of the disease is also known as blackpox.
At the beginning, or form of fulminate, bleeding occurs on the second or third day because sub conjunctival hemorrhage changes the white red-eye. Hemorrhagic pox also produces blackish erythema, petechiae, and bleeding in the spleen, kidney, serosa, muscle, and, rarely, epicardium, liver, testes, ovaries and bladder. Death often occurs suddenly between the fifth and seventh day of the illness, when there are only a few unimportant skin lesions. The last form of the disease occurs in patients who survive for 8-10 days. Bleeding occurs in the early eruption period, and the rash is flat and does not progress beyond the vesicular stage. Patients in the early stages of the disease show decreased coagulation factors (eg platelets, prothrombin, and globulin) and increased antithrombin circulation. Patients in the late stages have significant thrombocytopenia; deficiency of coagulation factor is less severe. Some in the later stages also show an increase in antithrombin. This form of smallpox occurs anywhere from 3 to 25 percent of fatal cases depending on the virulence of smallpox strains. Hemorrhagic pox is usually fatal.
Cause
Smallpox is caused by variola virus infection, which belongs to the genus Orthopoxvirus, Poxviridae family and chordopoxvirinae subfamily.
Evolution
Date of smallpox not completed. Most likely evolved from terrestrial African rat viruses between 68,000 and 16,000 years ago. The wide range of dates is due to the different notes used to calibrate the molecular clock. One clade is a variola major strain (a form of clinically more severe pox) that spreads from Asia between 400 and 1,600 years ago. The second clade includes alastrim minor (small phenotypic smallpox) described from the American continent and isolates from West Africa deviating from the ancestral strains between 1,400 and 6,300 years before present. This clade subsequently deviated into two subclasses at least 800 years ago. The second estimate has placed the separation of variola from Taterapox at 3000-4000 years ago. This is consistent with archaeological and historical evidence of the emergence of smallpox as a human disease that shows a relatively new origin. If the mutation rate is assumed to be equal to the herpes virus, the date of the difference between the variola of the Taterapox was estimated 50,000 years ago. While this is consistent with other published estimates, it shows that archaeological and historical evidence is very incomplete. It is estimated that a better rate of mutation in this virus.
Examination of strains originating from ~ 1650 found that these strains were basal to the currently ordered strains. The rate of virus mutation is well modeled by molecular clocks. Diversification of strains occurred only in the 18th and 19th centuries.
Virology
Variola is a large brick-shaped virus measuring about 302 to 350 nanometers by 244 to 270 nm, with double genome double-stranded genome 186 pairs of kilobase (kbp) in size and contains a hairpin loop at each end. Two varieties of classic smallpox are variola major and variola minor.
Four orthopoxviruses cause infection in humans: variola, vaccinia, cowpox, and monkeypox. Variola viruses only infect humans in nature, although primates and other animals have been infected in laboratory settings. Vaccinia, cowpox, and monkeypox virus can infect humans and other animals in nature.
The poxvirus life cycle is complicated by having some form of infection, with different cell entry mechanisms. Poxviruses are unique among DNA viruses in which they replicate in the cell cytoplasm rather than in the nucleus. To replicate, poxviruses produce a variety of special proteins that are not produced by other DNA viruses, most important of which are DNA-dependent RNA polymerases.
Both the enveloped and the non-developed virions are contagious. The virus envelope is made of a modified Golgi membrane containing a specific viral polypeptide, including hemagglutinin. Infection with one of the major variola or variola minor provides immunity to the other.
Transmission
Transmission occurs through inhalation of air variola virus, usually droplets expressed from the oral, nasal, or pharyngeal mucosa of an infected person. It is transmitted from one person to another primarily through prolonged face-to-face contact with an infected person, usually within 6 feet (1.8 m), but can also be spread by direct contact with infected body fluids or contaminated objects (fomites ) such as bedding or clothing. Rarely, smallpox has spread by viruses carried in the air in closed settings such as buildings, buses, and trains. The virus can cross the placenta, but the incidence of congenital pox is relatively low. Smallpox is not particularly contagious in the prodromal period and viral shedding is usually delayed until the onset of a rash, which is often accompanied by lesions in the mouth and pharynx. Viruses can be transmitted throughout the course of the disease, but most commonly occur during the first week of the rash, when most of the skin lesions are intact. Infectivity decreases within 7 to 10 days when scabies is formed over lesions, but infected people are contagious until the last smallpox fall.
Smallpox is highly contagious, but it generally spreads more slowly and less widely than some other viral diseases, probably because the transmission requires close contact and occurs after the onset of a rash. The overall rate of infection is also affected by the short duration of the infection stage. In temperate climates, the number of smallpox infections is highest during winter and spring. In the tropics, seasonal variations are less clear and the disease is present throughout the year. The age distribution of smallpox infection depends on the acquired immunity. Vaccination immunity declines over time and may disappear within thirty years. Chickenpox is not known to be transmitted by insects or animals and there are no asymptomatic carrier conditions.
Diagnosis
Clinical definitions of smallpox are diseases with acute febrile onsets equal to or greater than 38.3 Ã, Â ° C (101Ã, Â ° F) followed by rashes characterized by vesicles or pustules that are strong and deep in the same stages of development without another. the obvious cause. If clinical cases are observed, smallpox is confirmed using laboratory tests.
Microscopically, poxviruses produce characteristic cytoplasmic inclusions, most importantly known as Guarnieri bodies, and are the site of viral replication. Guarnieri's body is readily identifiable in skin biopsy stained with hematoxylin and eosin, and appears as a pink blob. They are found in almost all poxvirus infections but the absence of Guarnieri bodies can not be used to get rid of smallpox. The diagnosis of orthopedic virus infection can also be done quickly by examination of pustular fluid electron microscopy or scabs. All orthopoxviruses show a brick-shaped virion identical to an electron microscope. If the morphological particles characteristic of herpes virus are seen this will eliminate smallpox and other orthopoxvirus infections.
The definitive laboratory identification of variola virus involves growing the virus on the chorioallantoic membrane (part of the chicken embryo) and examining the pock lesions produced under prescribed temperature conditions. Strains can be characterized by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis. Serological tests and enzyme linked immunosorbent assays (ELISA), which measure variola immunoglobulin and virus-specific antigen have also been developed to help diagnose the infection.
Chickenpox is generally confused with smallpox in the post-extermination era soon. Smallpox and smallpox can be distinguished by several methods. Unlike smallpox, chicken pox usually does not affect the palms of the hands and soles of the feet. In addition, smallpox pustules vary in size due to the variation in pustule eruption time: smallpox pustules are almost the same size as the effect of the virus develops more uniformly. Various laboratory methods are available to detect smallpox in the evaluation of suspected cases of smallpox.
Prevention
The earliest procedure used to prevent smallpox is inoculation (known as variation after the introduction of smallpox vaccine to avoid possible confusion), which is likely to occur in India, Africa, and China long before practice arrives in Europe. The idea that inoculation originated in India has been challenged, as some ancient Sanskrit medical texts describe the inoculation process. Inoculation accounts against smallpox in China can be found at the beginning of the 10th century, and this procedure was widely practiced in the 16th century, during the Ming dynasty. If successful, inoculation produces long-lasting immunity against smallpox. Because the person is infected with the variola virus, severe infection can occur, and the person may pass the smallpox to another person. Variation has a death rate of 0.5-2 percent, far less than the 20-30 percent mortality rate of the disease. Two reports of Chinese inoculation practices were accepted by the Royal Society in London in 1700; one by Dr. Martin Lister received a report by an employee of an East India Company stationed in China and another by Clopton Havers.
Lady Mary Wortley Montagu observed the inoculation of smallpox during her stay in the Ottoman Empire, wrote a detailed report on the practice in her letters, and enthusiastically promoted the procedure in England back in 1718. In 1721, Cotton Mather and colleagues provoked controversy in Boston by injecting hundreds. In 1796, Edward Jenner, a physician in Berkeley, Gloucestershire, rural England, found that immunity to smallpox could be produced by inoculating a person with the material from a cowpox lesion. Smallpox is a poxvirus in the same family with variola. Jenner refers to the material used for inoculation vaccine, from the verb vacca , which is Latin for cattle. The procedure is much safer than variolation, and does not involve the risk of smallpox transmission. Vaccinations to prevent smallpox are immediately carried out around the world. During the 19th century, the cowpox virus used for smallpox vaccination was replaced by the vaccinia virus. Vaccinia is present in the same family as cowpox and variola, but is genetically different from both. The origin of the vaccinia virus and how the vaccine is unknown. According to Voltaire (1742), Turks used their injection to neighbor Circassia. Voltaire did not speculate on where the Circassians derived their technique, although he reported that the Chinese had practiced it "one hundred years".
The formulation of the smallpox vaccine today is the live virus preparation of the infectious vaccinia virus. The vaccine is given using a branched needle (two branches) dipped in a vaccine solution. The needle is used to puncture the skin (usually the upper arm) several times in a few seconds. If successful, a red and itchy bump develops on the vaccine site in three or four days. In the first week, the lump becomes a large blister (called "Jennerian vesicles") filled with pus, and begins to flow. During the second week, the blisters begin to dry and form a scab. The scab fell in the third week, leaving a small scar.
The antibody induced by the vaccinia vaccine is a cross protector for other orthopoxviruses, such as monkeypox, cowpox, and variola (smallpox) virus. Neutral antibodies can be detected 10 days after first vaccination, and seven days after re-vaccination. Historically, vaccines have been effective in preventing smallpox infections in 95 percent of those vaccinated. Smallpox vaccination provides high levels of immunity for three to five years and lowers immunity afterwards. If someone is vaccinated again later, immunity will last longer. Case studies of smallpox in Europe in the 1950s and 1960s showed that mortality rates among people vaccinated less than 10 years before exposure were 1.3 percent; it was 7 per cent among those vaccinated 11 to 20 years earlier, and 11 per cent among those vaccinated 20 years or more before the infection. In contrast, 52 percent of unvaccinated people died.
There are side effects and risks associated with smallpox vaccine. In the past, about 1 in 1,000 people vaccinated for the first time experienced a serious, but not life-threatening reaction, including toxic or allergic reactions in the vaccination site (erythema multiforme), the spread of the vaccinia virus to another. body parts, and to other individuals. Potentially life-threatening reactions occur in 14 to 500 people from every 1 million people vaccinated for the first time. Based on past experience, it is estimated that 1 or 2 people in 1 million (0.000198 percent) who receive the vaccine can die as a result, most often the result of post-vaccinal encephalitis or severe necrosis in the vaccination area (called progressive vaccinia).
Given this risk, since smallpox becomes effectively eradicated and the number of cases occurring naturally drops below the number of illnesses and deaths from vaccines, routine childhood vaccinations were halted in the United States in 1972, and abandoned in most of the early European countries 1970s. Regular health care workers' vaccinations were halted in the US in 1976, and among military recruits in 1990 (although military personnel who spread to the Middle East and Korea still received vaccinations). By 1986, routine vaccination had stopped in all countries. It is now especially recommended for laboratory workers at risk of occupational exposure.
Treatment
Smallpox vaccination within three days of exposure will prevent or significantly reduce the severity of smallpox symptoms in most people. Vaccinations four to seven days after exposure may offer some protection from the disease or may modify the severity of the disease. In addition to vaccinations, smallpox treatment is particularly supportive, such as wound care and infection control, fluid therapy, and ventilator assistance. Types of smallpox and hemorrhagic are treated with the same therapy used to treat shock, such as fluid resuscitation. Persons with confluent and confluent semi pox may have therapeutic problems similar to those with extensive skin burns.
No drug approved for the treatment of smallpox. Antiviral treatment has increased since the last major smallpox epidemic, and studies have shown that antidrally cidofovir drugs may be useful as therapeutic agents. Drugs should be given intravenously, and can cause serious kidney poisoning.
Prognosis
The overall case fatality rate for the common type of smallpox is about 30 percent, but varies according to the spotted distribution: the fatal type of fatal confluent is about 50-75 percent time, the usual type of semi-confluent is about 25-50 percent of the time, in cases where the rash is discrete case fatality rate is less than 10 percent. The overall mortality rate for children younger than 1 year is 40-50 percent. Hemorrhagic and flat types have the highest mortality rates. The mortality rate for flat type was 90 percent or more and nearly 100 percent was observed in cases of hemorrhagic pox. The case-fatality rate for variola minor is 1 percent or less. There is no evidence of chronic or recurrent infection with variola virus.
In the case of fatal smallpox, death usually occurs between the tenth and sixteen days of the disease. The cause of death due to smallpox is not clear, but the infection is now known to involve many organs. Immune complex circulation, immense viral load, or uncontrolled immune response can be a contributing factor. In early hemorrhagic pox, death occurs suddenly about six days after the fever develops. The cause of death in hemorrhagic cases involves heart failure, sometimes accompanied by pulmonary edema. In advanced haemorrhagic cases, high and sustained viremia, severe platelet loss and poor immune responses are often cited as the cause of death. In chickenpox death mode is similar to that in burns, with loss of fluids, proteins and electrolytes beyond the body's capacity to replace or obtain, and fulminate sepsis.
Complications
Complications of smallpox occur most frequently in the respiratory system and range from simple bronchitis to fatal pneumonia. Respiratory complications tend to develop around the eighth day of the disease and may be viral or bacterial originating. Secondary bacterial infection of the skin is a relatively rare complication of smallpox. When this happens, the fever usually remains high.
Other complications include encephalitis (1 in 500 patients), which is more common in adults and may cause temporary disability; permanent perforated scars, especially on the face; and eye-related complications (2 percent of all cases). Pustules can form on the eyelid, conjunctiva, and cornea, leading to complications such as conjunctivitis, keratitis, corneal ulcers, iritis, iridocyclitis, and optic atrophy. Blindness produces about 35 to 40 percent of eyes affected by keratitis and corneal ulcers. Hemorrhagic pox may cause subconjunctival and retinal hemorrhage. In 2 to 5 percent of young children with smallpox, virions reach the joints and bones, causing osteomyelitis variolosa . Lesions are symmetrical, most common in elbows, tibia, and fibula, and characteristically lead to separation of epiphysis and marked periosteal reactions. A swollen belly restricts movement, and arthritis can lead to limb deformities, ankylosis, defective bones, fatigue joints, and fat fingers.
History
The emergence of the disease
The most credible clinical evidence of smallpox is found in diseases such as smallpox in medical writings from ancient India (as early as 1500 BC), Egyptian mummies Ramses V who died more than 3000 years ago (1145 BC) and China (1122 BC). ). It has been speculated that Egyptian traders brought smallpox to India during the first millennium BC, where it remained as an endemic human disease for at least 2000 years. Smallpox was probably introduced to China during the 1st century CE from the southwest, and in the 6th century it was brought from China to Japan. In Japan, the epidemic 735-737 is believed to have killed as many as a third of the population. At least seven religious deities have been specifically dedicated to smallpox, like the god Sopona in Yoruba religion. In India, the Hindu pox goddess, Sitala Mata, is worshiped in temples across the country.
A different point of view is that smallpox appears 1588AD and the previously reported case is incorrectly identified as smallpox.
The arrival time of smallpox in Europe and southwest Asia is less clear. Smallpox is not clearly described either in the Old or New Testament of the Bible or in the literature of the Greeks or Romans. While some people have identified the Athens Outbreak - which is said to have originated from "Ethiopia" and Egypt - or an outbreak that lifted the 396 BC Carthage siege from Syracuse - with smallpox, many experts agree it is highly unlikely such a serious illness such as variola major will be escaped described by Hippocrates if it had existed in the Mediterranean region during his lifetime. While the Antonine Plague that struck the Roman Empire in 165-180 AD was probably caused by smallpox, Saint Nicolas of Rheims became the patron saint of the victims of smallpox for allegedly surviving the battle in 450, and Saint Gregory Tours noted similar things. outbreaks in France and Italy in 580, the first use of the term variola ; Other historians speculate that Arab troops first brought smallpox from Africa to Southwest Europe during the 7th and 8th centuries. In the 9th century, the Persian physician Rhazes gave one of the most definitive descriptions of smallpox and was the first to distinguish smallpox from measles and smallpox in his book [Kitab fi al-jadari wa-al-hasbah] > Book of Smallpox and Measles ). During the Middle Ages, smallpox made periodic attacks into Europe but did not become established there until the population increased and the population movement became more active during the Crusading era. By the 16th century smallpox was established in much of Europe. With its introduction to populated areas of India, China and Europe, smallpox mainly affects children, with periodic epidemics that kill as many as 30 percent of those infected. The existence of smallpox in Europe is of great historical importance, as the successive wave of exploration and colonization by Europeans tends to spread disease to other parts of the world. In the 16th century it has become an important cause of morbidity and mortality worldwide.
There is no credible description of diseases such as smallpox in America before the westward exploration by Europeans in the 15th century. Smallpox was introduced to the Caribbean island of Hispaniola in 1509, and to the mainland in 1520, when Spanish settlers from Hispaniola arrived in Mexico carrying smallpox with them. Smallpox destroyed the indigenous population of Amerindian and was an important factor in the conquest of the Aztecs and Incas by the Spaniards. The northeastern coastal settlement of North America in 1633 in Plymouth, Massachusetts was also accompanied by a devastating outbreak of smallpox among Native Americans, and later among native-born colonies. The case-fatality rate during outbreaks in Native Americans is as high as 80-90%. Smallpox was introduced to Australia in 1789 and again in 1829. Although the disease never plagued the continent, it was the leading cause of death in the Aboriginal population between 1780 and 1870.
By the middle of the 18th century smallpox is a major endemic disease everywhere in the world except in Australia and in some small islands. In Europe smallpox was the leading cause of death in the 18th century, killing about 400,000 Europeans every year. Up to 10 percent of Swedish babies die of smallpox every year, and the infant mortality rate in Russia may be even higher. The wide use of variations in some countries, especially the United Kingdom, its North American colonies, and China, somewhat reduced the impact of smallpox among the wealthy classes during the latter part of the 18th century, but the apparent decline in incidents did not occur until vaccination became common practice by the end of the century to-19. The increase in vaccines and the practice of re-vaccination led to substantial reductions in cases in Europe and North America, but smallpox remains virtually out of control elsewhere in the world. In the United States and South Africa a much lighter form of smallpox, variola minor , was recognized just before the close of the 19th century. By the middle of the 20th century variola minor occurred along with variola major, in various proportions, in many parts of Africa. Patients with variola minor have only mild systemic disease, are often ambulances during the course of the disease, and therefore can more easily spread the disease. Infection with v. minor induces immunity to more lethal forms of variola major . So like v. minor scattered throughout the United States, to Canada, South American and British countries became the dominant form of smallpox, further reducing mortality rates.
Eradication
British physician Edward Jenner demonstrated the effectiveness of cowpox to protect humans from smallpox in 1796, after which efforts were made to eliminate smallpox at a regional scale. In Russia in 1796, the first child to receive this treatment was named "Vaccinov" by Catherine the Great, and was educated at the expense of the nation. The introduction of the vaccine to the New World took place in Trinity, Newfoundland in 1800 by Dr. John Clinch, childhood friend and medical colleague Jenner. In early 1803, the Spanish Empire organized Balmis's expedition to transport vaccines to Spanish colonies in America and the Philippines, and made a mass vaccination program there. The US Congress passed the Vaccine Act of 1813 to ensure that the smallpox vaccine would be safely available to the American public. In about 1817, a very solid state vaccination program existed in the Dutch East Indies. In British India, a program was launched to spread smallpox vaccinations, through an Indian vaccinator, under the supervision of European officials. However, British vaccination efforts in India, and in Burma in particular, are hampered by stubborn indigenous preferences for inoculation and vaccination distrust, despite harsh legislation, increased local efficacy of vaccines and vaccine preservatives, and educational efforts. In 1832, the United States federal government established a smallpox vaccination program for Native Americans. In 1842, the United Kingdom forbade inoculation, then developed into a mandatory vaccination. The British Government introduced mandatory smallpox vaccinations by the Parliament Act in 1853. In the United States, from 1843 to 1855 the first Massachusetts, and then other states required the vaccination of smallpox. Although some people do not like these measures, coordinated efforts against smallpox continue, and the disease continues to dwindle in rich countries. In Northern Europe a number of countries have deprived smallpox in 1900, and by 1914, incidence in most industrialized countries declined to a relatively low level. Vaccination continued in industrialized countries, until the mid to late 1970s as protection against reintroduction. Australia and New Zealand are two exceptions; do not have endemic pox and are never vaccinated extensively, relying only on strict distance and quarantine protection.
The first cerebral hemispheric effort to combat smallpox was created in 1950 by the Pan American Health Organization. This campaign succeeded in removing smallpox from all American countries except Argentina, Brazil, Colombia, and Ecuador. In 1958 Professor Viktor Zhdanov, Deputy Minister of Health for the Soviet Union, asked the World Health Assembly to initiate a global initiative to combat smallpox. The proposal (Resolution WHA11.54) was accepted in 1959. At this point, 2 million people die from smallpox every year. Overall, progress towards eradication is disappointing, especially in Africa and in the Indian subcontinent. In 1966 an international team, the Smallpox Combat Unit, was formed under the leadership of an American, Donald Henderson. In 1967, the World Health Organization intensified global smallpox elimination by donating $ 2.4 million annually to the effort, and adopted a new disease surveillance method promoted by Czech epidemic expert Karel Ra? Ka.
In the early 1950s an estimated 50 million cases of smallpox occurred in the world each year. To eradicate smallpox, every outbreak should be stopped from spreading, with case isolation and vaccination of all those living close by. This process is known as "ring vaccination". The key to this strategy is case monitoring in a community (known as surveillance) and detention. The initial problem facing the WHO team is the inadequate reporting of smallpox cases, as many cases do not concern the authorities. The fact that humans are the only reservoir for smallpox infection, and that carriers do not exist, plays an important role in the eradication of smallpox. WHO established a network of consultants who assist countries in regulating surveillance and detention activities. Initially, vaccine donations were given primarily by the Soviet Union and the United States, but by 1973, more than 80 percent of all vaccines were produced in developing countries.
The last major European smallpox epidemic occurred in 1972 in Yugoslavia, after a pilgrim from Kosovo returned from the Middle East, where he contracted the virus. The epidemic infected 175 people, causing 35 deaths. Authorities declared martial law, enforced quarantine, and widely re-vaccinated populations, seeking help from WHO. Within two months, the outbreak has ended. Prior to this, there had been a smallpox outbreak from May-July 1963 in Stockholm, Sweden, brought from the Far East by a Swedish sailor; this has been addressed by quarantine measures and vaccination of local residents.
At the end of 1975, smallpox survived only in the Horn of Africa. Conditions are very difficult in Ethiopia and Somalia, where there are several roads. Civil war, famine, and refugees make the task more difficult. Intensive surveillance and detention and vaccination programs were undertaken in these countries in the early and mid-1977, under the direction of Australian microbiologist Frank Fenner. As the campaign approaches its goal, Fenner and his team play a key role in verifying extermination. The last native case of smallpox ( Variola minor) was diagnosed in Ali Maow Maalin, a hospital chef in Merca, Somalia, on October 26, 1977. The last more lethal natural case Variola major was detected in October 1975 to a two-year-old Bangladeshi girl, Rahima Banu.
The global eradication of smallpox has been certified, based on intense verification activities in countries, by a commission of eminent scientists on December 9, 1979 and then endorsed by the World Health Assembly on 8 May 1980. The first two sentences of the resolution read:
After considering the development and outcomes of a global program for the eradication of smallpox initiated by WHO in 1958 and intensified since 1967... Declare earnestly that the world and its people have won freedom from smallpox, which is the most devastating disease that sweeps in the form epidemics through many countries since the earliest times, leaving death, blindness and disability built and only a decade ago rampant in Africa, Asia and South America.
Post-eradication
The last case of smallpox in the world occurred in the outbreak of two cases (one fatal) in Birmingham, United Kingdom, in 1978. Medical photographer, Janet Parker, developed the disease at the University of Birmingham Medical School and died. on September 11, 1978. Professor Henry Bedson, the scientist responsible for smallpox research at the university, committed suicide. All known cacar reserves were then destroyed or transferred to two WHO-designated reference laboratories with BSL-4 facilities - the United States Centers for Disease Control and Prevention and the Russian Center for Virology and Vector Research of Biotechnology.
WHO first recommended the destruction of the virus in 1986 and then set the date of destruction to December 30, 1993. This was postponed until 30 June 1999. Due to resistance from the US and Russia, in 2002 the World Health Assembly agreed to allow temporary viral stock retention for specific research purposes. Destroying existing stocks will reduce the risk involved with ongoing smallpox research; stock is not needed to respond to smallpox outbreaks. Some scientists argue that stock may be useful in developing new vaccines, antiviral drugs, and diagnostic tests; the 2010 review by a team of public health experts appointed by WHO concluded that no important public health goals are served by the US and Russia that continue to maintain virus stocks. The latter view is often supported in the scientific community, especially among WHO Smallpox Program veteran veterans.
In March 2004, smallpox scabs were found inside the envelope in a book on Civil War medicines in Santa Fe, New Mexico. The envelope was labeled as containing scabs from vaccinations and gave scientists at the Centers for Disease Control and Prevention an opportunity to study the history of smallpox vaccinations in the United States.
On July 1, 2014, six sealed glass bottles of cacar dated 1954, along with other pathogenic sample bottles, were found in cold storage rooms at the FDA laboratory at the National Institutes of Health in Bethesda, Maryland. The smallpox bowl was then transferred to CDC prisoners in Atlanta, where viruses taken from at least two vials proved to be living in culture. After the study, CDC destroyed the virus based on WHO's observations on February 24, 2015.
By 2017, Canadian scientists recreate an extinct horseshoe virus to show that smallpox viruses can be recreated in a small laboratory costing about $ 100,000, by a team of scientists with no special knowledge. This makes controversy controversy moot because viruses can be easily created even if all samples are destroyed. Although scientists are conducting research to assist in the development of new vaccines as well as tracking the history of smallpox, the possibility of techniques used for malicious purposes is immediately recognized, leading to new regulatory questions.
Society and culture
Biological warfare
Britain used smallpox as a biological war agent at the Siege of Fort Pitt during the French and Indian Wars (1754-1763) against France and its Native American allies. Actually, the use of smallpox has formal sanction. British officers, including British-led generals, ordered, sanctioned, paid and used smallpox against Native Americans. As the historian explains, "there is no doubt that the British military authority approved the attempt to spread smallpox among enemies," and "it was a deliberate British policy to infect Indians with smallpox." On June 24, 1763, William Trent, a local merchant and commander of the Fort Pitt militia, wrote, "Because we respected them, we gave them two Blankets and Handkerchiefs from Small Pox Hospital, I hope it will have the desired effect." The effectiveness of efforts to broadcast the disease is unknown. There are also reports that smallpox was used as a weapon during the American Revolutionary War (1775-1783).
According to a theory put forward in the Journal of Australian Studies (JAS) by an independent researcher, in 1789, the British Marines used smallpox against indigenous tribes in New South Wales. This event was also discussed earlier in the Medical History Bulletin and by David Day in his book Claiming the Continent: A History of New Australia. Before the JAS article this theory was debated by some academics. Jack Carmody claimed the cause of the outbreak was more likely due to chicken pox, which at that time was sometimes identified as a mild form of smallpox. While it is noted that, in the course of the First Fleet 8 months and the subsequent 14 months there were no reports of smallpox among colonists and that since smallpox has an incubation period of 10-12 days then it is unlikely to be present in the first fleet, it is now known that the possible source is a virus bottle smallpox owned by First Fleet surgeons and there is actually a cacar report among the colonists - a sailor, Jefferies.
During World War II, scientists from Britain, the United States and Japan (Unit 731 of the Imperial Japanese Army) engaged in research to produce biological weapons from smallpox. Large-scale production plans have never been done because they assume that the weapon will not be very effective due to widespread availability of the vaccine.
In 1947, the Soviet Union set up a smallpox weapon factory in the town of Zagorsk, 75 km to the northeast of Moscow. The outbreak of weaponized pox occurred during testing at a facility on an island in the Aral Sea in 1971. General Professor Peter Burgasov, former Chief of Sanitary Doctor of the Soviet Army and senior researcher in the Soviet biological weapons program, described the incident. :
On Vozrozhdeniya Island in the Aral Sea, the strongest cacar prescription is tested. Suddenly I was told that there were mysterious cases of death in Aralsk. An Aral fleet research boat comes to within 15 km of the island (it is forbidden to come closer than 40 km). The lab technician of this ship takes plankton samples twice a day from the upper deck. Formulation of smallpox - 400 gr. from being exploded on the island - "got him" and he became infected. After returning home to Aralsk, he infected several people including children. They all died. I suspect the reason for this and called the Chief of Staff of the Department of Defense and asked to stop the Alma-Ata-Moscow train stop in Aralsk. As a result, epidemics across the country are prevented. I telephoned Andropov, who was then the Head of the KGB, and told him about a special recipe for smallpox obtained on Vozrazhdenie Island.
Others argue that the first patient may have the disease while visiting Uyaly or Komsomolsk-on-Ustyurt, the two towns on which the ship is docked.
In response to international pressure, in 1991 the Soviet government allowed a joint US-British inspection team to tour four of its major weapons facilities in Biopreparat. The inspectors were filled with evasion and resistance from Soviet scientists, and were eventually ordered out of the facility. In 1992, Soviet defector Ken Alibek alleged that the Soviet bioweapons program at Zagorsk had produced a large inventory - as much as twenty tons - of cacar weapons (possibly engineered to reject the vaccine, alibek further accused), along with a refrigerated warhead to deliver it.. Alibek's stories about the activities of smallpox Soviet programs have never been independently verified.
In 1997, the Russian government announced that all remaining smallpox samples would be transferred to the Vector Institute in Koltsovo. With the breakup of the Soviet Union and the unemployment of many weapons program scientists, US government officials have expressed concern that smallpox and the expertise to ignite it may already be available to other governments or terrorist groups who may want to use the virus as a means of biological warfare. The specific allegations made against Iraq in this case proved wrong.
Concern has been revealed by some that the synthesis of artificial genes can be used to recreate viruses from existing digital genomes, for use in biological warfare. The insertion of DNA of smallpox synthesized into related pox viruses could be theoretically used to recreate the virus. The first step to mitigate this risk, it has been suggested, should destroy the remaining viral stocks thus allowing a firm criminalization of any viral ownership.
In 2017, Bill Gates stated that bioterrorism with smallpox could be more dangerous than nuclear weapons.
Important case
Well-known historical figures with smallpox include the Lakota's Chief, Banting V of Egypt, Emperor Kangxi (survivors), Emperor Shunzhi and Emperor Tongzhi (referring to official history) China, Emperor Komei of Japan (died of smallpox in 1867), and Date Masamune from Japan (who lost eyes for illness). CuitlÃÆ'¡huac, tlatoani (ruler) 10 of the Aztec town Tenochtitlan, died of smallpox in 1520, shortly after its introduction to America, and Inca Huayna Capac emperor died in 1527. Newest public figures include Guru Har Krishan, , in 1664, Peter II of Russia in 1730 (died), George Washington (congratulations), king of Louis XV in 1774 (died) and Maximilian III Joseph, the Bavarian Voter in 1777.
Leading families around the world often have some people who are infected by and/or lost from the disease. For example, some families of Henry VIII survived the disease but were wounded by it. This included his sister Margaret, Queen of Scots, his fourth wife, Anne of Cleves, and his two daughters: Mary I of England in 1527 and Elizabeth I of England in 1562 (as an adult he often tried to disguise pockmark with heavy grooming). His niece, Mary, Queen of Scots, has had the disease since childhood but has no scar tissue.
In Europe, deaths from smallpox often change the succession of dynasties. The only surviving son of Henry VIII, Edward VI, died of an immediate complication after recovering from the disease, thereby canceling Henry's attempt to ensure a male successor to the throne (two immediate successors were the two women, both of whom had had it and survived.). Louis XV of France replaced his great-grandfather, Louis XIV, through a series of smallpox or measles deaths among those who were previously in the line of succession. He himself died of illness in 1774. William III lost his mother to illness when he was only ten years old in 1660, and named his uncle Charles the legal guardian: his death from smallpox would indirectly trigger a series of events that would ultimately lead to permanent overthrow Stuart's line from the British throne. William III's wife, Mary II of England, died of smallpox as well.
In Russia, Peter II of Russia died of disease at the age of 15 years. Also, before becoming the Russian Emperor, Peter III caught the virus and suffered greatly from it. He left scars and defects. His wife, Catherine the Great, was spared but the fear of the virus clearly affected him. He is afraid for his son and the safety of Pavel's heirs so much that he ensures that a large crowd is kept at bay and seeks to isolate him. Eventually, he decides to have himself inoculated by a Scottish physician, Thomas Dimsdale. Currently considered a controversial method at the time, he succeeded. His son Pavel was then inoculated as well. Then Catherine attempted an injection into his entire empire by declaring: "My goal is, by my example, to save from the deaths of many of my people who, without knowing the value of this technique, and their fears, are left in danger." In 1800, about 2 million injections were done in the Russian Empire.
In China, the Qing Dynasty has an extensive protocol to protect Manchus from the Peking endemic pox.
US President George Washington, Andrew Jackson, and Abraham Lincoln all contracted and recovered from the disease. Washington became infected with smallpox on a visit to Barbados in 1751. Jackson developed the disease after being imprisoned by the British during the American Revolution, and although he recovered, his brother Robert did not. Lincoln contracted the disease during his Presidency, probably from his son Tad, and was quarantined shortly after giving the Gettysburg address in 1863.
The famous theologian Jonathan Edwards died of smallpox in 1758 after inoculation.
Soviet leader Joseph Stalin fell ill with smallpox at the age of seven. His face was badly injured by the disease. He then has retouched photos to make his pockmarks less clear.
Hungarian poet Ferenc KÃÆ'¶lcsey, who wrote the Hungarian national anthem, lost his right eye because of smallpox.
Traditions and religions
In the face of the destruction of smallpox, various smallpox gods and goddesses have been worshiped in all parts of the Old World, for example in China and in India. In China, the pox goddess is referred to as T'ou-Shen Niang-Niang. The Chinese believers actively work to pacify the goddess and pray for her compassion, with measures like referring to smallpox pustules as "beautiful flowers" as euphemisms meant to prevent offending goddesses, for example (the Chinese word for smallpox is ??, literally "Paradise flower"). In the associated New Year's Eve habit, it is prescribed that the children at home wear a bad mask during sleep, thus hiding any beauty and thus avoiding attracting the goddess, who will pass a moment of the night. If a case of smallpox occurs, holy sites will be established in the homes of the victims, to be worshiped and offered as a disease. If the victim recovers, the shrine is removed and taken away on a special paper chair or boat to be burned. If the patient does not recover, the temple is destroyed and cursed, thus driving away the goddess from home.
The first record of smallpox in India can be found in a medical book dating from A.D. 400. This book describes a disease that sounds very similar to smallpox. India, like China, created a goddess in response to her exposure to smallpox. The Hindu Goddess, Shitala, was worshiped and feared during his reign. It is believed that this goddess is both evil and good and has the ability to inflict a victim while angry, and soothe the fever she has suffered. The portrait of the goddess shows her holding a broom in her right hand to continue removing cold water sickness and pans on the other side in an effort to calm the victim. Temples are made where many indigenous Indians, healthy and not, go to worship and try to protect themselves from this disease. Some Indian women, in an effort to ward off Shitala, put plates of cooling food and water pots on the roofs of their homes.
In a culture that does not recognize the god of smallpox, there is often a belief in the smallpox devil, who is blamed for the disease. Such beliefs stand out in Japan, Europe, Africa, and other parts of the world. Almost all cultures who believe in Satan also believe that they are afraid of red. This led to the discovery of what is called a red treatment, in which the victims and their rooms will be decorated in red. This practice spread to Europe in the 12th century and was practiced by (among others) Charles V of France and Elizabeth I of England. The scientific credibility revealed by the study by Finsen shows that red light reduces scarring, this belief persisted even until the 1930s.
Movies and novels
- Smallpox 2002 , a fictitious bioterrorism movie about the smallpox epidemic
- New York's Killer Killer , a fictitious movie about smallpox outbreak
- Variola Vera , the 1972 epidemic of the Yugoslav smallpox
- The Demon in the Freezer , a non-fiction book about smallpox eradication, and the ongoing threat of bioterrorism
See also
- List of epidemics
- History of Native American Population # Depopulation of the disease
References
Further reading
External links
- Biosafety Smallpox: Website About Destruction of Smallpox Virus Reserves
- Detailed cache cache of CIDRAP
- Agent Fact Sheet: Smallpox, Biosecurity Center
- Thumbnail and Synopsis Diagnosis
- Variola Virus Genome database search results from Poxvirus Bioinformatics Resource Center
- References Pathogen Virus and Resource Analysis (ViPR): Poxviridae
Source of the article : Wikipedia
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