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How does smallpox spread?

Smallpox is spread by inhaling saliva or mucus droplets from an infected individual. After about 7 to 17 days, flulike symptoms begin; these include high fever, body aches, and fatigue. Within a few days a body rash develops that quickly evolves into pus-filled blisters, or pustules. By the second week the pustules form crusts, which dry out and turn into scabs. After a week or so the scabs fall off, leaving deep and often disfiguring scars. The mortality rate of smallpox is very high—up to 30 percent of its victims die from the disease. Those who do not die may suffer from complications of the disease, which include blindness, pneumonia, and kidney damage. No adequate treatment is available to fight the virus, though antibiotics may be prescribed to hinder secondary bacterial infections. The virus is remarkably stable and can exist in the environment and on bedding and clothing for extended periods of time.

Large outbreaks of smallpox have occurred throughout history, affecting individuals from all walks of life. Smallpox was responsible for the deaths of Queen Mary II of England, Emperor Joseph I of Austria, King Luis I of Spain, Tsar Peter II of Russia, Queen Ulrika Elenora of Sweden, and King Louis XV of France. Although the vaccine discovered by Jenner in 1796 was effective, it was not used consistently; by the 1950s, roughly 50 million cases of smallpox still occurred worldwide each year.

The disastrous mortal disease known as the Black Death spread across Europe in the years 1346-53. The frightening name, however, only came several centuries after its visitation (and was probably a mistranslation of the Latin word ‘atra’ meaning both ‘terrible’ and ‘black)’. Chronicles and letters from the time describe the terror wrought by the illness. In Florence, the great Renaissance poet Petrarch was sure that they would not be believed: ‘O happy posterity, who will not experience such abysmal woe and will look upon our testimony as a fable.’

The tragedy was extraordinary. In the course of just a few months, 60 per cent of Florence’s population died from the plague, and probably the same proportion in Siena. In addition to the bald statistics, we come across profound personal tragedies: Petrarch lost to the Black Death his beloved Laura to whom he wrote his famous love poems; Di Tura tells us that ‘I [...] buried my five children with my own hands

The Black Death was an epidemic of bubonic plague, a disease caused by the bacterium Yersinia pestis that circulates among wild rodents where they live in great numbers and density. Such an area is called a ‘plague focus’ or a ‘plague reservoir’. Plague among humans  arises when rodents in human habitation, normally black rats, become infected. The black rat, also called the ‘house rat’ and the ‘ship rat’, likes to live close to people, the very quality that makes it dangerous (in contrast, the brown or grey rat prefers to keep its distance in sewers and cellars). Normally, it takes ten to fourteen days before plague has killed off most of a contaminated rat colony, making it difficult for great numbers of fleas gathered on the remaining, but soon- dying, rats to find new hosts. After three days of fasting, hungry rat fleas turn on humans. From the bite site, the contagion drains to a lymph node that consequently swells to form a painful bubo, most often in the groin, on the thigh, in an armpit or on the neck. Hence the name bubonic plague. The infection takes three–five days to incubate in people before they fall ill, and another three–five days before, in 80 per cent of the cases, the victims die. Thus, from the introduction of plague contagion among rats in a human community it takes, on average, twenty-three days before the first person dies.

Painful diarrhea, high fever, nasty red rashes and sleeplessness typically characterize the illness.

Left untreated, typhoid can result in death.

Salmonella typhi, the parasite that causes typhoid fever, spreads through water and food, making the disease highly contagiou

The Great Plague, also known as the Black Death or bubonic plague, is the topic of discussion in this report. More terrible than the previous outbreaks of plague in London, the Great Plague started in the poorest areas of London and this report provides you with the details on how it was transmitted and spread. Information on the treatment of plague victims demonstrates the misinformation about the plague that existed during the seventeenth century. The symptoms of the plague are described is provided along with excerpts from the diary of Samuel Pepys.

Sixty percent of Europe's population died in the Black Death, a spread of bubonic plague in the mid-14th century. Deep pits were dug at all the church cemeteries, and each held many bodies with a layer of dirt added each day. Letters and chronicles tell of the personal tragedies of those who buried spouses or children. The disease was spread by rats that lived in houses and on ships. Infected fleas bit humans after the rats in a colony died. In a few days, victims fell ill. In a few more, 80% of them died. Investigate the spread.

In the autumn of 1348, a central Asian sickness arrived in London and quickly dispatched 60 percent of the city’s population. Within a decade, in what’s believed to be the worst human calamity of all time, something like 25 million Europeans were dead. And when they died, the secrets of their demise disappeared with them. Until now. On Sunday, London scientists who’d studied 25 skeletons discovered in a new rail line announced that those bones held traces of the black death. Most of the ensuing coverage focused on an unrelated theory that the disease wasn’t likely spread by rats’ fleas, as has been taught in every high school in the West, but had perhaps been airborne.

London

Black Death Victims in the Middle Ages - TreatmentsThe Black Death victims in the Middle Ages were terrified of the deadly disease. The plague held a massive mortality rate between 30 and 40%. Victims had no idea what had caused the disease. Neither did the physicians in the Middle Ages. The most that could be done was that various concoctions of herbs might be administered to relieve the symptoms - there was no known cure. Headaches were relieved by rose, lavender, sage and bay. Sickness or nausea was treated with wormwood, mint, and balm. Lung problems were treated with liquorice and comfrey. Vinegar was used as a cleansing agent as it was believed that it would kill disease. But bloodletting was commonly thought to be one of the best ways to treat the plague. The blood that exuded was black, thick and vile smelling with a greenish scum mixed in it.Black Death Treatment: Black Death was treated by lancing the buboes and applying a warm poultice of butter, onion and garlic. Various other remedies were tried including arsenic, lily root and even dried toad. During a later outbreak of this terrible plague, during the Elizabethan era, substances such as tobacco brought from the New World were also used in experiments to treat the disease.

Black Death in England - 1348-1350 The Black Death reached England in 1348. Bristol was an important European port and city in England during the Medieval era. It is widely believed that Bristol was the place where the Black Death first reached England. The plague reached England during the summer months between June and August. The Back Death reached London by 1st November 1348. London was a crowded, bustling city with a population of around 70,000. The sanitation in London was poor and living conditions were filthy. The River Thames brought more ships and infection to London which spread to the rest of England. The crowded, dirty living conditions of the English cities led to the rapid spread of the disease. Church records that the actual deaths in London were approximately 20,000. Between 1348 and 1350, killed about 30 - 40% of the population of England which at the time was estimated to be about five to six million. Many people were thrown into open communal pits. The oldest, youngest and poorest died first. Whole villages and towns in England simply ceased to exist after the Black Death.

The Black Death and ReligionDuring the Middle Ages it was essential that people were given the last rites and had the chance to confess their sins before they died. The spread of the deadly plague in England was swift and the death rate was almost 50% in isolated populations such as monasteries. There were not enough clergy to offer the last rites or give support and help to the victims. The situation was so bad that Pope Clement VI was forced to grant remission of sins to all who died of the Black Death. Victims were allowed to confess their sins to one another, or "even to a woman". The church could offer no reason for the deadly disease and beliefs were sorely tested. This had such a devastating effect that people started to question religion and such doubts ultimately led to the English reformation.

In the fall of 1918 the Great War in Europe was winding down and peace was on the horizon.

The Americans had joined in the fight, bringing the Allies closer to victory against the Germans. Deep within the trenches these men lived through some of the most brutal conditions of life, which it seemed could not be any worse. Then, in pockets across the globe, something erupted that seemed as benign as the common cold. The influenza of that season, however, was far more than a cold. In the two years that this scourge ravaged the earth, a fifth of the world's population was infected. The flu was most deadly for people ages 20 to 40. This pattern of morbidity was unusual for influenza which is usually a killer of the elderly and young children. It infected 28% of all Americans (Tice). An estimated 675,000 Americans died of influenza during the pandemic, ten times as many as in the world war. Of the U.S. soldiers who died in Europe, half of them fell to the influenza virus and not to the enemy (Deseret News). An estimated 43,000 servicemen mobilized for WWI died of influenza (Crosby). 1918 would go down as unforgettable year of suffering and death and yet of peace. As noted in the Journal of the American Medical Association final edition of 1918:

The influenza pandemic circled the globe. Most of humanity felt the effects of this strain of the influenza virus. It spread following the path of its human car

Route of transmission: Smallpox can be spread through indirect or direct contact with the infected, it can spread by being exposed to contaminated objects, to bodily fluids from an infected person, to having a short conversation with an infected persons.  Dryer climates can slightly increase the rate of transmission.

The Black Death: Bubonic Plague In the early 1330s an outbreak of deadly bubonic plague occurred in China. The bubonic plague mainly affects rodents, but fleas can transmit the disease to people. Once people are infected, they infect others very rapidly. Plague causes fever and a painful swelling of the lymph glands called buboes, which is how it gets its name. The disease also causes spots on the skin that are red at first and then turn black.

Mary Mallon, now known as Typhoid Mary, seemed a healthy woman when a health inspector knocked on her door in 1907, yet she was the cause of several typhoid outbreaks. Since Mary was the first "healthy carrier" of typhoid fever in the United States, she did not understand how someone not sick could spread disease -- so she tried to fight back.

during the High Middle Ages (1000-1300)

Waste accumulated in the streets for lack of sewer systems

traced back to the Gobi Desert of Mongolia in the 1320s.

Smallpox is a potentially deadly infectious disease, now eradicated worldwide after successful global immunization programs. Over the centuries before being eliminated, smallpox devastated populations worldwide.

What Causes Smallpox: The Variola Virus Smallpox is caused by the variola virus. There are two forms of this virus. The more dangerous form, variola major, caused smallpox disease that was fatal for about 30% of people infected. A virus called variola minor caused a less deadly form of smallpox, with a fatality rate of about 1%. 

How Smallpox Is Spread Smallpox disease is highly contagious. It spreads from person to person primarily by breathing in the virus, which is transmitted in saliva, during close, face-to-face contact with an infected person.

three waves, the Spanish flu spread quickly, killing an estimated 50 million to 100 million people around the world. Dates: March 1918 to spring 1919

This new, deadlier flu acted very strangely; it seemed to target the young and healthy, being particularly deadly to 20 to 35 year olds. This deadly flu spread quickly around the world, infecting hundreds of millions of people and killing upwards of 5 percent of the world's population.

Most people have little or no immunity to a pandemic virus. Infection and illness rates soar. A substantial percentage of the world’s population will require some form of medical care.Nations are unlikely to have the staff, facilities, equipment, and hospital beds needed to cope with the number of people who get the pandemic flu.Death rates may be high. Four factors largely determine the death toll:The number of people who become infectedThe strength of the virusThe underlying characteristics and vulnerability of affected populationsThe effectiveness of preventive measures 

Yellow fever

Yellow fever (YF) is a viral haemorrhagic fever transmitted by infected mosquitoes. Yellow fever can be recognized from historic texts stretching back 400 years. Infection causes a wide spectrum of disease, from mild symptoms to severe illness and death. The "yellow" in the name is explained by the jaundice that affects some patients, causing yellow eyes and yellow skin. There are three types of transmission cycle: sylvatic, intermediate and urban. All three cycles exist in Africa, but in South America, only sylvatic and urban yellow fever occur.

Sylvatic (or jungle) yellow fever occurs in tropical rainforests where monkeys, infected by sylvatic mosquitoes, pass the virus onto other mosquitoes that feed on them; these mosquitoes, in turn bite and infect humans entering the forest. This produces sporadic cases, the majority of which are often young men working in the forest e.g. logging. The intermediate cycle of yellow fever transmission occurs in humid or semi-humid savannahs of Africa, and can produce small-scale epidemics in rural villages. Semi-domestic mosquitoes infect both monkey and human hosts and increased contact between man and infected mosquito leads to disease. This is the most common type of outbreak seen in recent decades in Africa. Urban yellow fever results in large explosive epidemics when travellers from rural areas introduce the virus into areas with high human population density. Domestic mosquitoes, most notably Aedes aegypti, carry the virus from person to person. These outbreaks tend to spread outwards from one source to cover a wide area. Yellow fever can be prevented by vaccination. In order to protect people living in areas at high risk of yellow fever transmission, WHO's dual strategy for prevention of yellow fever epidemics relies on preventive mass immunization campaigns followed by infant routine immunization. Yellow fever causes epidemics that can affect 20% of the population. When epidemics occur in unvaccinated populations, case-fatality rates may exceed 50%. No treatment beyond supportive care exists. For more information