Smallpox

Smallpox Classification and external resources
Young boy suffering from smallpox with an eruption vesicular - pustular typical face.
ICD - 10	B03.
ICD - 9	050
DiseasesDB	12219
MedlinePlus	001356
eMedicine	emerg/885
MeSH	D012899

Smallpox or is a contagious disease original virus , highly contagious and epidemic caused by a poxvirus. It has been totally eradicated 26 October 1977 (when the last known case in Somalia , a hospital cook ^Virus

Transmission electron microscopy of pox virus.

It is part of pox viruses that cause among other things:

• The molluscum contagiosum , a small benign tumor of the skin;
• smallpox, there are two variants Variola major and Variola minor (the latter being commonly called Smallpox Smallpox classical or Asian) easily distinguishable in the laboratory, but which nevertheless have very different case fatality rate (1 and 30% respectively ) which could cast doubt on the uniqueness of the disease. The existence of two forms of smallpox was approached from Jenner, but it was not until 1929 that the term of Variola minor is to prevail. For Variola minor, you can still Variola alastrim, peculiar to America, South Variola minor that it was in Africa at one time proposed to see two different kinds, it was not successful .
• The vaccine , which has created the first vaccines and reached several animal species: cow, monkey, etc..

History

Known in China where old she had been introduced in the year 49 AD, it is generally accepted that smallpox was introduced into Europe by the Arab invasions , following the outbreak of Mecca in 572. However, several scholars have also wanted to see behind the smallpox epidemic that struck the Roman Empire during the reign of Marcus Aurelius , commonly called Antonine plague. The plague then spread worldwide, causing over the centuries of terrible pandemics responsible for millions of deaths. It is especially the most virulent diseases that decimated populations Amerindian during the conquest of the New World, upon his arrival in 1518.

Mechanism

It is a disease exclusively inter-human and there is no animal reservoir of the virus.

The front door is usually the respiratory tract, although other routes of contamination are possible. An initial viral replication occurs at the level of the epithelium of the bronchi, without causing any symptoms. The virus then spreads to the reticuloendothelial system and leads to the first signs of the disease. The first lesion is frequently at the pharynx , allowing the release of virus into the atmosphere. The skin is achieved by transferring the virus to that level by the macrophages.

The disease, if it does not kill the patient is immune: reinfection with the same virus is impossible for years (even decades). Other sources claim that immunity is durable for life ^Description

The period between infection and first symptoms (incubation period) is typically 10 to 14 days. The eruption was preceded by a fever for a few days with chills, headache, nausea ...

The rash is characterized by the appearance of red spots on the skin, turning into vesicles , then pustules form a crust before. The extent is variable and is closely linked to disease progression (a larger eruption is a criterion of gravity). The lesions are most common on the face and palms. The lesion is rarely hemorrhagic (bleeding), but in this case, extremely serious.

Smallpox was a scourge dreaded and feared. It killed one in five (adults, nearly one patient out of three). When she did not kill, it was often a face pockmarked and disfigured for life. She has remained out of reach of effective treatment.

The differential diagnosis must be made with chicken pox. The latter also has an incubation period of 14 to 16 days (range 10-21 days), the prodromal symptoms such as fever and headache, rash on the scalp , trunk and face. The main difference between smallpox and chickenpox: the lesions of chickenpox (in order macules , papules , vesicles , crusts) does not change all at once. It can thus be simultaneously papules, vesicles, etc.. Unlike smallpox .

Fight against smallpox

The story of the fight against smallpox can be divided into three periods: the first phase of variolation , then that of vaccination , and finally that of the global eradication campaign (1958-1977).

Variolation

In India, smallpox was described in books ayurveda. The cure ayurvedic passed by the inoculation of a "smallpox material" one year old, from pustules of people who contracted smallpox in the previous year. The effectiveness of this method was demonstrated by the British physician JZ Holwell in a report to the College of Physicians in London in 1767.

The first written mention of smallpox comes from a doctor in Alexandria, Aaron. From the ^eleventh century , the Chinese practiced variolation : it was hoped to inoculate a form that few virulent by contacting the person to be immunized with the content of the substance of a suppurating blisters ill. The Prime Minister Wang Dan who after losing a son of smallpox had convened various practitioners throughout China to develop a prophylactic. A monk Taoist brought the inoculation technique which spread gradually throughout China.

But these early origins are questioned by some authors ^, and the first mention of variolation appears indisputable in China in the sixteenth century .

The result, however, remained uncertain and risky, the mortality rate could reach 1 or 2%. The practice has gradually spread along the Silk Road. In 1701 , Giacomo Pylarini made the first inoculation in Constantinople.

The technique is imported in the West in the early ^eighteenth century by Lady Mary Wortley Montagu , wife of the ambassador from Britain to Turkey, who learns of Dr. Emmanuel Timoni (ca 1670-1718) , physician the embassy of Great Britain in Istanbul. A graduate of the University of Padua, a member of the Royal Society of London since 1703, Dr. Timoni published in 1713 in the Philosophical Transactions of the Royal Society his treatise on inoculation. His work has reissued the following year at Leipzig. From that date, the literature on this subject is increasing, Pylarino in 1715, Leduc and Maitland in 1722 ... It was introduced in France later. The first truly mediated inoculation is conducted by Dr. Theodore Tronchin in 1756 on children of the Duke of Orleans . In 1760 , Daniel Bernoulli showed that, despite the risks, the spread of this practice would save a little more than three years of life expectancy at birth. However, it aroused the hostility of many physicians .

Vaccination Jenner

For the first time, the 1770s until 1791, at least six people were tested, each independently, the possibility of immunizing human smallpox by inoculating them with cow pox, which was present on the udder cow. Among those who made the first tests are in 1774, an English farmer Benjamin Jesty on behalf of, and in 1791, a German schoolmaster named Peter Plett . In 1796, the English physician Edward Jenner will make the same discovery and fought so that we formally recognize the good result of immunization. On 14 May 1796 , when he inoculated a child of pus on the hand of a farm infected with vaccinia (via contact with infected cow's udder), or cow pox ("cow pox" in English). Three months later, he inoculated smallpox in the child, who resisted, thus revealing themselves immunized against the virus. This practice then spread gradually throughout Europe. Nevertheless, smallpox remained endemic throughout the ^nineteenth century and has gradually disappeared from Europe after the First World War.

For the record, the vaccination at that time was to remove pus from the pustules and directly infect humans with ^{Outbreak of the 1885 Montreal}

Total Eradication of smallpox

Girl from Bangladesh reached in 1973.

In 1950, the Pan American Health Organization, based on a novel method developed by Collier, undertook to eradicate smallpox in the Americas (this will be achieved in 1967 (except Brazil) .

The Soviet Union moved in 1958 to fully eradicate smallpox, which was then 2 million people per year worldwide. The project was taken that year by the World Health Organization (WHO) . The original strategy proposed by the USSR, an estimated vaccination rate of 80% would be enough to eradicate the virus . The vaccination campaign nevertheless proves difficult to implement.

The final report of the Global Commission for the Certification of the Eradication of WHO noted: "The eradication campaigns based entirely or mainly on mass vaccination was successful in some countries but failed in most cases.

WHO changes its strategy in 1967, implementing the "strategy of containment and surveillance" , which is to isolate cases and to vaccinate all those who lived around epidemic outbreaks. An international team formed under the leadership of the American Donald Henderson.

The eradication campaign was met first at the problem of identifying outbreaks, all is not necessarily identified. The social, cultural and political also played an important role. Thus, in India and Bangladesh , many Hindus were opposed to vaccination for fear of offending Shitala Devi , the goddess associated with smallpox. In addition, one year, heavy rains during the monsoon broke the dams and dykes , forcing people to flee, which had the effect of extending the new outbreak, which was eradicated at the end of one year of effort. On Sudan , he was plunged into civil war, exposing health teams with increased risks (which did, however no casualties to deplore).

The last major European outbreak of smallpox occurred in 1972 in Yugoslavia. A young Kosovar returning from a pilgrimage to Mecca and Iraq caught smallpox. The epidemic affects 38 people, including 6 die . The Tito regime then declared martial law , imposed quarantine and began a massive campaign of re-vaccination of the population, with the assistance of WHO and the team from Henderson. The epidemic was curbed in two months. A few years ago, another source of infection was reported in Sweden (May-July 1963). This was also eradicated through quarantine and vaccination .

The last case of spontaneous severe form of smallpox (Variola major) was registered in Bangladesh in October 1975 with a girl two years, Rahima Banu. From this date, smallpox was considered eradicated in virtually all the world, with the exception of the Horn of Africa. Indeed, poor health infrastructure and roads of Ethiopia and Somalia made it very difficult to mass vaccination had been successful elsewhere. In addition, there also armed conflicts , the famine and the migrations of refugees , which further complicated the task. Nevertheless an intensification of vaccination measures, surveillance, containment, in early 1977, the last case of smallpox was diagnosed in a natural way in Merca in Somalia, October 26, 1977.

In 1980, the three former directors of the Programme of global eradication of smallpox read the text formally announcing the success of this company.

The global eradication of smallpox was certified by an expert commission 9 December 1979 and officially declared by WHO, 8 May 1980 in resolution WHA33.3 ^,

Vaccination was discontinued due to this success.

After eradication

Although smallpox no longer Circulate in the human population, some medical laboratories had kept stocks of variola virus. However, in August 1978, Janet Parker , a photographer from the School of Medicine, University of Birmingham presented himself to hospital with symptoms of smallpox. Serologic tests confirmed his status and she died Sept. 11 of that year as a result of the disease. Professor Henry Bedson, head of research on smallpox in this laboratory committed suicide shortly after.

Therefore it was decided that all known stocks of the virus would be destroyed or transferred to one of two laboratories accredited by WHO, the Centers for Disease Control and Prevention (CDC) in the United States and the Centre National de Recherche Virology and Biotechnology (VECTOR) in Koltsovo in USSR. In 1986, WHO recommended that eventually the complete destruction of these viruses for December 30, 1993. But after an initial postponement to June 30, 1995, the decision was postponed and then canceled in 2002. Even if the total destruction of stocks reduces the risk of an accident leading to a new outbreak of disease, these viruses can be useful for biomedical research and for development of new vaccines, antiviral drugs, etc..

In March 2004, samples of smallpox virus were discovered in Santa Fe in an envelope inserted between pages of a book of medicine dating from the Civil War ; These samples are being analyzed by the CDC to understand the history of smallpox during the centuries.

France

The Central Committee of the vaccine created in 1803 and affiliated with the Academy of Medicine in 1820 directs campaigns vaccination.La circular dated 08.26.1880 subject to the vaccine only to graduates (previously, priests, religious , notables, teachers, etc.. had assisted). Vaccination from arm to arm remains the most common until the 1880s . The authorities complain of the low number of children vaccinifres - pustules were harvested on their flesh used for immunization vaccinations - attributed to the opposition of the families. This obstacle will disappear in the last decade of the century following the adoption of the first "animal vaccine," then the method of preservation of the pulp vaccine which will eliminate the presence of heifers during immunization sessions. If vaccinations are often provided free of charge to indigents, it does not take much as free or widely practiced. The creation of a public vaccination is discussed in which the independent status of medicine weighs sure. Many voices are calling for mandatory immunization, which alone can overcome restive populations and little access to any health education whatsoever. In the colonies, this requirement was instituted earlier than in metropolis and in 1876 in Cochin. In 1843, 1858 and 1880, several bills have an obligation to vaccine fail.

On 15 February 1902, the Law on Protection of Public Health, in Article 6, makes mandatory smallpox vaccination during the first year of life and re-vaccination of the tenth and twenty-first year .

The last smallpox epidemic of November 1954 in Vannes. Sergeant Roger Debuigny was visiting his family in Brittany, bringing with it the tang of Saigon would have been contaminated. There were 16 deaths out of 73 cases . Smallpox has killed many famous men in France, including, among others, King Louis XV.

Vaccination is not compulsory in France since 1979 , and reminders are no longer mandatory since 1984.

After 1980

Officially, two strains were kept for research at the Center for Disease Control (CDC) in Atlanta (USA) and the State Institute of Virology and Biotechnology in Koltsovo (Russia). Both laboratories were originally created for the purpose of biological warfare during the Cold War. Recently, and particularly following the anthrax attacks in the United States in 2001, some institutions have highlighted the possible use of smallpox as' biological weapon.

In 1999, a committee of the WHO announced that the reserves of available vaccines are too limited and must boost production of vaccines. A survey by WHO in 1998 estimated the number of doses available worldwide at 90 million .

Therefore, the United States, France and other countries have boosted the production of vaccine against smallpox, especially after the attacks of September 11, 2001 attacks and the anthrax .

Monkeypox

The monkeypox virus or monkeypox or , which circulates so endemic in the rainforests of Central and West Africa, can be transmitted to humans, causing a syndrome whose clinical manifestations are similar to those of smallpox (pustular rash, fever, respiratory symptoms with a fatal outcome in some cases). ICD-10 : B04. ^Cowpox

A similar virus also exists in cattle, the virus of cowpox. The vaccine was manufactured and originally with strips of leather cow infected with cowpox, the pustules being crushed and injected intravenously to patients. The first cow that Edward Jenner helped to produce this new vaccine in 1796 was named Blossom. His horns are observable Jenner Museum in Berkeley, England.

Terrorist Threats

Fearing the use of smallpox in a terrorist context, rigorous monitoring of biochemists and strains was decided by certain ^{People who had suffered from smallpox}

Several historical figures have contracted smallpox:

• It is believed that the Pharaoh Ramses V ( -1150 to -1145 ) would have died because of suggestive skin lesions are present on the face of his mummy.
• Chinese emperors Kangxi ( 1654 to 1722 ), Shunzhi ( 1638 to 1661 ) and perhaps Tongzhi ^References

Leave a Reply