DOCSLIB.ORG

The Puzzling Origins of AIDS

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Puzzling Origins of AIDS The Puzzling Origins of AIDS Although no one explanation has been universally accepted, four rival theories provide some important lessons Jim Moore hortly after the 1983 discovery of or to the mid-20th century, as well as its an experimental oral polio virus vaccine Sthe human immunodeficiency vi- absence previously in the New World took place from 1957 to 1960 in what are rus (HIV), the pathogen responsible for (which imported some 10 million Afri- now the Democratic Republic of the Con- AIDS, investigators became aware of can slaves during the 16th through 19th go, Burundi and Rwanda, seemingly the a strangely similar immune deficiency centuries), that transfer appears to have “hearth” of the global AIDS epidemic. disease afflicting Asian monkeys (ma- happened relatively recently—exactly When interviewed by Curtis, Hilary Ko- caques) held in captivity in various U.S. when is a point of considerable debate. prowski, the polio-vaccine pioneer who research labs. Soon, virologists identified And why did two distinct simian vi- mounted that massive campaign, could the culprit: a simian immunodeficiency ruses with which humans have appar- not recall or find documentary evidence virus (SIV) that is found naturally in a ently coexisted for centuries, or even as to whether his group had used kid- West African monkey species, the sooty millennia, suddenly pass into humans ney cells from green monkeys or Asian mangabey (Cercocebus atys), but is harm- multiple times within a few decades? macaques (which do not naturally carry less to that host. This virus, denoted The answers to these questions have an SIV). If culture media contained SIV SIVsm, is genetically similar to a weakly been slow in coming, despite the con- (a possibility, given that the techniques contagious form of the AIDS virus that is siderable efforts of molecular biologists available during that era were unable largely restricted to parts of West Africa, to understand the nature and evolution HIV-2, and thus is considered its likely of primate immunodeficiency viruses. Figure 1. Investigators puzzle over why the precursor. More recent work has shown I am not one of those molecular biolo- AIDS epidemic struck when it did. A simian that the closest relative of the primary hu- gists; rather, I became a player in the virus very similar to HIV-1 (the HIV type re- sponsible for the vast majority of AIDS cases) man immunodeficiency virus (HIV-1) is field of AIDS-origin research through is found in the chimpanzees of Central Africa, another simian immunodeficiency virus, my interest in chimpanzee socioecol- suggesting that these animals naturally harbor one carried by chimpanzees (SIVcpz). ogy. Although I am partial to a theo- the progenitor virus. The leading idea is that After comparing the SIVs in chimpan- ry I helped to fashion for why AIDS this virus first passed through cuts to someone zees and sooty mangabeys with HIV-1 emerged when it did, with time it might hunting or butchering a chimpanzee, but this and HIV-2 strains, investigators conclud- become clear that a competing idea bet- theory alone cannot explain why the AIDS ed that there must have been multiple ter accounts for genesis of the epidemic. epidemic did not arise before the 20th century, transmission “events” from simians to Or perhaps the answer will prove to lie because hunting chimpanzees for meat has humans—at least seven for HIV-2 (some with some complex combination of fac- presumably been going on for thousands of of which are known from only a single tors that no single explanation presently years. The author and two of his students sug- gested that the forced labor and population person who lives near mangabeys carry- encompasses. Whatever the case, the movements imposed on the natives of Central ing a uniquely similar SIV) and three for solution almost certainly will come from Africa during the colonial era—and the unster- HIV-1, the virus now infecting some 40 one or more of four competing theories. ilized needles used in health campaigns as- million people worldwide. sociated with those disruptions—might have How did SIVcpz and SIVsm cross Theory 1: Tainted Polio Vaccine created conditions favoring the transfer of the over into humans and become patho- The first theory is the most controversial. progenitor virus from chimpanzees to humans genic? Given the lack of historical refer- In a 1992 article in the magazine Rolling and its adaptation to become HIV. Vintage ences to AIDS-like disease in Africa pri- Stone, journalist Tom Curtis suggested postcards show some relevant scenes from the that HIV could have resulted from the region during the early part of the 20th century. use in Africa of an experimental oral po- Clockwise from top: vaccination in the Congo Free State (now Democratic Republic of the Jim Moore received his doctorate in biological an- lio vaccine (OPV), one contaminated by thropology from Harvard in 1985, where he studied Congo); Haute-Sangha (a province of what is a then-unknown SIV carried most prob- demography and sociality in primates. Since then now Central African Republic), doctor vacci- he has been on the faculty of the University of Cali- ably (Curtis supposed) by African green nates natives in the field; French Congo (now fornia, San Diego, where his research focuses on monkeys. Green-monkey kidney cells Republic of the Congo), missionaries vaccinate primate behavioral ecology. Address: Anthropology were widely used as a substrate to grow in the field in the vicinity of Brazzaville; Bel- Department, University of California, San Diego, viruses for research and vaccine produc- gian Congo (now Democratic Republic of the La Jolla, CA 92093. Internet: [email protected] tion. And one of the first major trials of Congo), construction of a bridge over a ravine. © 2004 Sigma Xi, The Scientific Research Society. Reproduction 540 American Scientist, Volume 92 with permission only. Contact [email protected]. © 2004 Sigma Xi, The Scientific Research Society. Reproduction www.americanscientist.org © 2004 Sigma Xi, The Scientific Research Society. Reproduction 2004 November–December 541 with permissionwith permission only. Contact only. [email protected]. Contact [email protected]. to guard against unknown viruses that Multiple localized strains of HIV have delphia) were tested and found nega- did not cause overt symptoms in their now been discovered, and mass vac- tive for both chimpanzee DNA and SIV. monkey hosts), more than 900,000 peo- cination appears unlikely to account for However, this result did not rule out ple might have received it with their all of them. But the early distribution of the possibility, previously suggested by medicine, laying the basis for the current the major pandemic strain, HIV-1 group Hooper, that local amplification of the epidemic. M (for “main”), seems to fit reasonably live-virus vaccine in Africa (to create Curtis credited this theory to Blaine well with the location of Koprowski’s more doses) could have introduced the Elswood, a Californian AIDS activist. campaigns, and the OPV theory now is SIV. The key issue is thus whether chim- Interestingly, the idea that the admin- applied primarily to this strain. panzee kidneys were used as a culture istration of a contaminated oral polio Contamination of OPV is the only one medium at any stage of Koprowski’s vaccine might have been involved in of the four current theories that is read- vaccine program. There is eyewitness the genesis of AIDS was suggested ily falsifiable: Finding the HIV-1 group testimony on both sides of this question, independently by two others at about M virus in a tissue sample that predated and failure to find SIVcpz in a handful the same time. The first to do so was the suspect vaccine would eliminate this of samples of the live vaccine strain of Louis Pascal, who like Elswood is not possibility. So far that has not happened. the type used in Africa does not prove a scientist. After years of rejections, Still, many investigators give the theory the virus was absent in (putative) locally Pascal, a New Yorker, finally man- little weight for other reasons, which produced batches. aged in 1991 to get the University of has led to the widespread belief that the A second reason to question the OPV Wollongong in Australia to publish a theory has been definitively disproved. theory also came to light in 2000, with a paper describing his ideas. Not sur- In 2001, for example, Science magazine report in Science by Bette T. Korber (of prisingly, few noticed it. Attorney published a piece titled “Disputed AIDS Los Alamos National Laboratory) and Walter Kyle also published a broadly Theory Dies its Final Death,” and Na- colleagues. They used molecular differ- similar theory in The Lancet, a British ture ran one under the heading “Polio ences among HIV-1 group M subtypes medical journal, in 1992. Since then, Vaccines Exonerated.” Earlier this year to estimate the date of their last com- writer Edward Hooper, author of the Nature also published “Origin of AIDS: mon ancestor. The conclusion: 1931 controversial 1999 book The River, has Contaminated Polio Vaccine Theory Re- (with 95 percent confidence limits giv- become the contaminated-vaccine the- futed”—a surprising title given that this ing the range 1915 to 1941), preceding ory’s most ardent supporter. Hooper, theory ostensibly died three years ago. OPV administration by decades. How- noting a passing mention by Curtis of The recent findings of various mo- ever, the calculation of such common- a chimpanzee colony run by Koprow- lecular biologists have indeed failed to ancestor dates can be thrown off by ge- ski’s team, suggested that kidneys provide support for the OPV theory. For netic recombination among subtypes from these chimpanzees—not from example, in 2000 a few existing samples (“viral sex”), which can make such dates green monkeys—may have been the of the vaccine from Koprowski’s home come out too early, and there is increas- original source of the virus.
Load more

Recommended publications
  • Poliomyelitis and Polio-Encephalitis
    POLIOMYELITIS AND POLIO-ENCEPHALITIS. 151 Postgrad Med J: first published as 10.1136/pgmj.2.22.151 on 1 July 1927. Downloaded from coryza, or gastro-intestinal symptoms such as vomiting and diarrhoea. The lymphatic glands are POLIOMYELITIS enlarged. The temperature rises, often ranging AND POLIO-ENCEPHALITIS.* between 101° and 103°F., and there is general malaise often accompanied by profuse sweating. BY In some cases both local and general symptoms are E. A. COCKAYNE, M.D. OXF., F.R.C.P. LOND., so slight that they may be overlooked and the PHYSICIAN TO THE MIDDLESEX HOSPITAL; PHYSICIAN rise of temperature may be very small. After TO OUT-PATIENTS, HOSPITAL FOR SICK CHILDREN, lasting from one to four days the illness may end GREAT ORMOND-STREET. at this stage. If it continues headache, drowsiness POLIOMYELITIS, like other specific fevers, has its and irritability, pain and stiffness in the back, special age and seasonal incidence; it is commonest accompanied sometimes by twitching of the in the late summer and early autumn, and the limbs or retraction of the head, may develop, and majority of its victims are children between the these indicate involvement of the meninges. ages of 1 and 5 years. The earliest symptoms are Hyperssthesia of skin and muscles may also be constitutional, malaise and fever, and in some prominent. Then if the grey matter of the central cases the involvement of the nervous system, to nervous system becomes infected, weakness, paresis, which it owes its name, never occurs. Such and paralysis of muscles develops. Paralyses cases are usually regarded as abortive, but in may appear to be dramatically sudden, but my opinion this view is not the correct one.
    [Show full text]
  • SOS – Save Our Shoulders: a Guide for Polio Survivors
    1 • Save Our Shoulders: A Guide for Polio Survivors A Guide for Polio Survivors S.O.S. Save Our Shoulders: A Guide for Polio Survivors by Jennifer Kuehl, MPT Roberta Costello, MSN, RN Janet Wechsler, PT Funding for the production of this manual was made possible by: The National Institute for Disability and Rehabilitation Research Grant #H133A000101 and The U.S. Department of the Army Grant #DAMD17-00-1-0533 Investigators: Mary Klein, PhD Mary Ann Keenan, MD Alberto Esquenazi, MD Acknowledgements We gratefully acknowledge the contributions and input provided from all of those who participated in our research. The time and effort of our participants was instrumental in the creation of this manual. Jennifer Kuehl, MPT Moss Rehabilitation Research Institute, Philadelphia Roberta Costello, MSN, RN Moss Rehabilitation Research Institute, Philadelphia Janet Wechsler, PT Moss Rehabilitation Research Institute, Philadelphia Mary Klein, PhD Moss Rehabilitation Research Institute, Philadelphia Mary Ann Keenan, MD University of Pennsylvania, Philadelphia Alberto Esquenazi, MD MossRehab Hospital, Philadelphia Cover and manual design by Ron Kalstein, MEd Albert Einstein Medical Center, Philadelphia Table of Contents 1. Introduction . .5 2. General Information About the Shoulder . .6 3. Facts About Shoulder Problems . .8 4. Treatment Options . .13 5. About Exercise . .16 6. Stretching Exercises . .19 7. Cane Stretches . .22 8. Strengthening Exercises . .25 9. Tips to Avoid Shoulder Problems . .29 10. Conclusion . .31 11. Resources . .31 The information contained within this manual is for reference only and is not a substitute for professional medical advice. Before beginning any exercise program consult your physician. Save Our Shoulders: A Guide for Polio Survivors • 4 Introduction Many polio survivors report new symptoms as they age.
    [Show full text]
  • What Having Had Polio Causes, Might Cause and Does Not Cause Marny K
    What Having Had Polio Causes, Might Cause and Does Not Cause Marny K. Eulberg, MD, Family Practice, Denver, Colorado Introduction: As time has elapsed since the major poliomyelitis epi- demics ended, following the widespread introduction of the polio vaccines, persons affected by polio, their families and their health- care providers seem to have less and less clear understanding about what symptoms are caused by polio, which are associated with polio and which are not. Many healthcare providers in practice today have had little experience or training in the care of polio survivors, and they studied the basic pathology that the poliovirus causes years ago. Organizations, such as Post-Polio Health International, which exist to provide information to polio survivors, are frequently asked questions Marny K. Eulberg, MD about various symptoms and the relationship to the acute polio. Post-polio groups and expert professionals have indicated that many individuals have been given incorrect or confusing information. Attributing symptoms or changes in symptoms and try to understand them. functioning to one’s previous polio Often a symptom can be caused by when the symptom is, in fact, due to many different mechanisms and a disease or condition that should be sometimes even by a combination treated by an entirely different medi- of factors. cal regime than polio/post-polio is not This article is not meant to be all- only not helpful but may be danger- inclusive and list every possible cause/ ous. Polio clinics can help with symp- disease but to discuss the most com- toms that are polio related and can mon and most frequent conditions.
    [Show full text]
  • Polio Fact Sheet
    Polio Fact Sheet 1. What is Polio? - Polio is a disease caused by a virus that lives in the human throat and intestinal tract. It is spread by exposure to infected human stool: e.g. from poor sanitation practices. The 1952 Polio epidemic was the worst outbreak in the nation's history. Of nearly 58,000 cases reported that year, 3,145 people died and 21,269 were left with mild to disabling paralysis, with most of the victims being children. The "public reaction was to a plague", said historian William O'Neill. "Citizens of urban areas were to be terrified every summer when this frightful visitor returned.” A Polio vaccine first became available in 1955. 2. What are the symptoms of Polio? - Up to 95 % of people infected with Polio virus are not aware they are infected, but can still transmit it to others. While some develop just a fever, sore throat, upset stomach, and/or flu-like symptoms and have no paralysis or other serious symptoms, others get a stiffness of the back or legs, and experience increased sensitivity. However, a few develop life-threatening paralysis of muscles. The risk of developing serious symptoms increases with the age of the ill person. 3. Is Polio still a disease seen in the United States? - The last naturally occurring cases of Polio in the United States were in 1979, when an outbreak occurred among the Amish in several states including Pennsylvania. 4. What kinds of Polio vaccines are used in the United States? - There is now only one kind of Polio vaccine used in the United States: the Inactivated Polio vaccine (IPV) is given as an injection (shot).
    [Show full text]
  • An Epidemic of Acute Encephalitis in Young Children
    Arch Dis Child: first published as 10.1136/adc.9.51.153 on 1 June 1934. Downloaded from AN EPIDEMIC OF ACUTE ENCEPHALITIS IN YOUNG CHILDREN BY AGNES R. MACGREGOR, M.B., F.R.C.P.E., AND W. S. CRAIG, B.Sc., M.D., M.R.C.P.E. (From the Departments of Pathology and Child Life and Health, Univer- sity of Edinburgh, and the Western General Hospital, Edinburgh.) This paper is concerned with a small outbreak of illness of an unusual nature occurring in the Children's Unit of the Western General Hospital, Edinburgh. In addition to the clinical interest of the cases, there are features of considerable pathological and epidemiological importance con- nected with the outbreak. Clinical Records. Case 1. I.M.S., female, aged 1 year 7 months, was admitted to the Western General Hospital in March, 1933, at the age of 1 year 3 months. - At this time http://adc.bmj.com/ she was noted as being slightly undersized but well nourished and the liver showed moderate enlargement. Prior to admission she had been treated elsewhere for gonococcal vaginitis: during the three succeeding months her health was good and progress uninterrupted, but a positive Wassermann reaction, present on admission, persisted. On the evening of July 22, 1933, the patient was noticed to be less active than usual and generally ' out of sorts ': her conditiQn remained unchanged throughout the rest of the day, and on the 23rd she was 'Ptill quieter and less responsive to all forms of attention and refused food. By the afternoon on October 2, 2021 by guest.
    [Show full text]
  • Polio Laboratory Manual
    WHO/IVB/04.10 ORIGINAL: ENGLISH Polio laboratory manual 4th edition, 2004 The World Health Organization has managed The evaluation of the impact of vaccine- cooperation with its Member States and preventable diseases informs decisions to provided technical support in the fi eld of introduce new vaccines. Optimal strategies vaccine-preventable diseases since 1975. and activities for reducing morbidity and In 2003, the offi ce carrying out this function mortality through the use of vaccines are was renamed the WHO Department of implemented (Vaccine Assessment and Immunization, Vaccines and Biologicals. Monitoring). The Department’s goal is the achievement Efforts are directed towards reducing fi nancial of a world in which all people at risk are and technical barriers to the introduction protected against vaccine-preventable of new and established vaccines and diseases. Work towards this goal can be immunization-related technologies (Access to visualized as occurring along a continuum. Technologies). The range of activities spans from research, development and evaluation of vaccines Under the guidance of its Member States, to implementation and evaluation of WHO, in conjunction with outside world immunization programmes in countries. experts, develops and promotes policies and strategies to maximize the use and delivery WHO facilitates and coordinates research of vaccines of public health importance. and development on new vaccines and Countries are supported so that they immunization-related technologies for viral, acquire the technical and managerial skills, bacterial and parasitic diseases. Existing competence and infrastructure needed to life-saving vaccines are further improved and achieve disease control and/or elimination new vaccines targeted at public health crises, and eradication objectives (Expanded such as HIV/AIDS and SARS, are discovered Programme on Immunization).
    [Show full text]
  • Coronavirus (COVID-19) and Polio Survivors Spring 2020
    Coronavirus (COVID-19) and Polio Survivors PHI Official Statement By Dr. Marny Eulberg Everyone seems to be talking about, worrying about, and asking questions about coronavirus and that includes polio survivors. As we have seen, this is a rapidly evolving situation and what we know today may change next week or next month. Some facts that are not likely to change are: Polio and late effects of polio do not, in themselves, cause immune compromise. Therefore, polio survivors are no more likely to contract a coronavirus infection or develop serious illness from it than people who never Spring 2020 Winter 2017 had polio! Wheelchairs & Getaway 1 Most polio survivors in the United States and COVID 2 Conserve to Canada are over 60 years old which places us in PHI New Resource 5 Preserve 2 Traveling Clinic 4 the “higher risk” category with a greater Exec. Committee Meetings 5 Pearls of Wisdom 5 likelihood of developing severe disease after Disaster being infected with the virus than younger FDA Removes 6 Zantac Preparedness 7 people. COVID & Polio 7 Sleep! Breathe! Polio survivors who had breathing muscle Caring for Live! 7 involvement with their original illness and/or Yourself 10 Probiotics & Bone now have respiratory problems of any kind are Calendar 13 Strength 12 at “high risk” when they become ill Executive 14 Executive with any respiratory infection including Council Committee 14 coronaviruses. Support Groups 14 Support Groups 14 {PHI COVID-19 continued on page 9} ATTENTION: Wheelchair and Assistive Technology Users PRECAUTIONS for COVID-19 Greetings from Beneficial Designs. My name is Peter Axelson.
    [Show full text]
  • Pn0607 Meningitis.Pdf
    Accurate diagnosis and an extensive work-up can avoid unnecessary treatments. As the meningitis season heats up, here’s how to be ready. iral meningitis is a significant cause of morbidi- nective tissue diseases, partially treated bacterial meningitis, ty and mortality. There are over 100,000 cases of parameningeal infections and drug-induced meningitis.2 aseptic meningitis annually in the United Some viral pathogens may cause “pure” meningitis in which States.1 The term “aseptic meningitis” refers to the signs of brain involvement and spinal cord inflammation both infectious and noninfectious causes of are absent. Viral infection may also result in a combined syn- meningitisV for which no etiology is identified after routine drome of menigoencephalitis or encephalomyelitis.3 The clini- evaluation and culture of the cerebrospinal fluid (CSF). The cal features associated with viral meningitis are often non-spe- differential diagnosis for aseptic meningitis is quite broad. cific, so awareness of epidemiology, including seasonality and Although viruses are the major cause of acute meningitis, the geographic distribution of the various pathogens, becomes clinical presentation and CSF findings are often indistinguish- important in establishing a diagnosis. Given the paucity of able from other causes of aseptic meningitis, presenting a diag- effective therapies for viral meningitis, preventive measures nostic challenge. Therefore, knowledge of unique clinical fea- have an important role in reducing morbidity and mortality. A tures and epidemiology for the causative agents of viral menin- detailed look at the unique characteristics of the common gitis is especially important for diagnosis, treatment and pre- pathogens in viral meningitis will aid in clinical recognition.
    [Show full text]
  • INFLAMMATORY/POST-INFECTIOUS ENCEPHALOMYELITIS L Bennetto, N Scolding I22
    J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.2003.034256 on 20 February 2004. Downloaded from INFLAMMATORY/POST-INFECTIOUS ENCEPHALOMYELITIS L Bennetto, N Scolding i22 J Neurol Neurosurg Psychiatry 2004;75(Suppl I):i22–i28. doi: 10.1136/jnnp.2003.034256 ost-infectious and inflammatory encephalomyelitis are broadly represented by the syn- drome acute disseminated encephalomyelitis (ADEM). ADEM forms one of several Pcategories of primary inflammatory demyelinating disorders of the central nervous system. Others include multiple sclerosis (MS), acute transverse myelitis, and Devic’s disease. It should be remembered that these are syndromically defined diseases at present. There are no diagnos- tic tests presently available short of brain biopsy, but future advances may reveal diagnostic biological markers of disease and in so doing dramatically advance the pathophysiological and therapeutic understanding of these conditions. A wholesale change in classification and nomenclature may well follow. In the meantime clinicians must remain keenly appreciative of subtle shades of grey: ADEM, first MS relapse, or ultimately benign clinically isolated syn- drome? The answers are relevant to prognosis and, more recently, selection of the correct therapeutic strategy. c ACUTE DISSEMINATED ENCEPHALOMYELITIS ADEM is an inflammatory demyelinating disorder of the central nervous system that is usually monophasic, but a relapsing variant distinct from MS—multiphasic disseminated encephalomyelitis (MDEM) is well-described. ADEM is predominantly, though by no means copyright. exclusively, a disease of children and in particular infants. Historically it includes post- infectious encephalomyelitis and post-vaccination encephalomyelitis. While these two syndromes were distinguished by their precipitant it was realised that clinically and pathologically they were very similar.
    [Show full text]
  • British Medical Journal
    BRITISH MEDICAL JOURNAL LONDON: SATURDAY, -JULY 11th, 1936 EPIDEMIC POLIOMYELITIS EPIDEMIOLOGY, CAUSES, AND PREVENTION * BY SIR ARTHUR S. MAcNALTY, K.C.B., M.A., M.D., F.R.C.P. CHIEF MEDICAL OFFICER OF THE MINISTRY OF HEALTH Poliomyelitis has been described by Simon Flexner as Wickman (1901 and 1905), Strauss (1910), and Peabody, " one of the saddest of diseases," and Dr. Thomas Buzzard Draper and Dochez (1912). characterized it as being " peculiarly cruel " to its hapless Striimpell gave the first complete account of the ceretral victims. Apart from the fact that the majority of the type of poliomyelitis (polio-encephalitis) in 1884. The first adult case of poliomyelitis was described by Vogt in 1859. sufferers are young children, it leaves a considerable pro- portion of the survivors permanently paralysed, and so crippled as to constitute for them a life-long handicap in Pathology the struggle for existence. The studies of Flexner and Lewis, Leiner and von and and others have The has been described by somewhat cumbrous Wiesner, Landsteiner Levaditi, malady shown that the disease is due to a virus which passes names. It is scientifically known as acute poliomyelitis through the finest filter and that the filtrate is capable of (including polio-encephalitis and polio-encephalo-myelitis). reproducing the disease in monkeys. The virus attacks " infantile It has long been known under the name of the nervous system, causing inflammation of- the grey paralysis," but the term is inisleading, for the disease may rmatter, especially of the anterior cornua of the spinal cord. occur in adults, though not so frequently as in children, Most I'he histological lesions are hyperaemia, exudation of and paralysis does not always supervene.
    [Show full text]
  • Chapter 18: Polio
    Poliomyelitis Concepcion F. Estivariz, MD; Ruth Link-Gelles, PhD, MPH; and Tom Shimabukuro, MD, MPH, MBA Descriptions of polio-like illnesses have been around since antiquity, including a funerary stele depicting a man with Poliomyelitis a withered leg leaning on a staff. Michael Underwood first ● First described by Michael described a debility of the lower extremities in children that was Underwood in 1789 recognizable as poliomyelitis in England in 1789, but the disease ● Developed countries in was not observed in epidemics until the late 19th century. Northern Hemisphere During the first half of the 20th century, developed countries in suffered increasingly severe the Northern Hemisphere suffered epidemics each summer and epidemics in the first half fall that became increasingly severe. Polio infections peaked in of the 20th century the United States in 1952, with more than 21,000 paralytic cases. Following introduction of effective vaccines in 1955 (inactivated ● More than 21,000 paralytic polio vaccine, IPV) and 1961 (oral poliovirus vaccine, OPV), cases reported in the U.S. polio incidence declined rapidly. The last case of wild poliovirus in 1952 acquired in the United States was in 1979. ● Last case of wild poliovirus acquired in the U.S. was 1979 Poliovirus Poliovirus is a member of the enterovirus subgroup, family Picornaviridae. Picornaviruses are small, ether-insensitive viruses Poliovirus with an RNA genome. ● Enterovirus (RNA) ● Three serotypes: type 1, type 2, There are three poliovirus serotypes (type1, type 2, and type type 3 3); immunity to one serotype does not produce significant immunity to the other serotypes. ● Immunity to one serotype does not produce significant Poliovirus is rapidly inactivated by heat, formaldehyde, chlorine, immunity to other serotypes and ultraviolet light.
    [Show full text]
  • Impact of the COVID-19 Pandemic on Polio Care: a Warning
    European Review for Medical and Pharmacological Sciences 2021; 25: 1167-1168 Impact of the COVID-19 pandemic on polio care: a warning Dear Editor, The recent coronavirus disease (COVID-19) pandemic has had an immense impact on health- care systems worldwide, which have to deal with the challenge of simultaneously responding to the needs of COVID-19 patients and managing other life-threatening disorders. Several Western and developed Asian countries (e.g., South Korea, Japan), hit by the pandemic had to substan- tially reorganize their healthcare systems, redistributing personnel and resources to deal with the uncontrolled spread of COVID-191. Many polio services and teams in many countries, including Pakistan, have been closed, according to local and WHO health resources and organizations2. These actions have impacted standard polio care, including the delivery of time-dependent treatments and patients’ relation- ships with their families. Every year on October 24, the world celebrates World Polio Day, particularly celebrating the determination that has enabled the world to almost completely eradicate polio. On this day, healthcare providers around the world consider how to eliminate this disease completely. In Africa, thousands of polio eradicators have fought the disease, and by the passing year, polio has been completely eradicated from Africa. However, in two countries worldwide, including Pakistan and Afghanistan, there is still transmission of wild poliovirus3. However, polio workers have faced many challenges in 2020 due to the COVID-19 pandemic. It has been estimated that, during the last eight months, eighty million infants have missed critical vaccines, leading to massive increase in many vaccine-preventable diseases, such as polio4.
    [Show full text]