Group items tagged

Paul I. Howell, MPH; Prof. Frank Hadley Collins/Centers for Disease Control and...Paul I. Howell, MPH; Prof. Frank Hadley Collins/Centers for Disease Control and Prevention (CDC) (Image Number: 9534)An infectious disease, yellow fever infects humans, all species of monkeys, and certain other small mammals. The virus is transmitted from animals to humans and among humans by several species of mosquitoes. Yellow fever is one of the great epidemic diseases of the tropical world, and in earlier centuries it was one of the great plagues of the New World. At one time the tropical and subtropical regions of

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.

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

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

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

A Great Plague killed nearly half of the people of Europe during in the fourteenth century. A plague is a widespread illness. The plague was also known as "the Black Death" because of the black spots that formed on the skin of diseased people. The devastation of the plague brought great changes to Europe.

The sickness apparently began in Central Asia. In 1347, Italian merchant ships returned from the Black Sea, one of the links along the trade route between Europe and China. The ships were dirty and infested with rats. Fleas living on the blood of infected rats transferred the disease to the seamen.

Many of the sailors were already dying of the plague as the infected ships returned to port, and within days of an infected ship's arrival, the disease spread from the port cities to the surrounding countryside. The plague reached Spain, France, England and Russia within three years. Although it is impossible to calculate exactly how many people died from the plague, evidence suggests that it claimed the lives of as many as 25 million Europeans.

that diseases are caused by microorganisms.

Building on this new understanding of disease, scientists and physicians achieved incredible successes, identifying fifty causative agents of diseases ranging from typhoid, tuberculosis, cholera, plague and malaria between 1880 and 1920.

Fever Headache Muscle pain Backache Chills Loss of appetite Nausea and/or vomiting

High fever Abdominal pain Bleeding from the gums, nose, eyes, and/or stomach Vomit that appears black due to blood content Low blood pressure Liver failure, which may lead to jaundice Kidney failure Confusion Seizure Coma

SymptomsYellow fever symptoms appear within a week after a person is bitten by an infected mosquito. Typically, acute phase symptoms will persist for 3 to 4 days, and then disappear. A small percentage of people progress into the toxic phase. The toxic phase symptoms begin within 24 hours of the end of the acute phase. Recovery from yellow fever provides lifetime immunity from the disease.

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.

n 1347 a Genoese ship from Caffa, on the Black Sea, came ashore at Messina, Sicily. The crew of the ship, what few were left alive, carried with them a deadly cargo, a disease so virulent that it could kill in a matter of hours. It is thought that the disease originated in the Far East, and was spread along major trade routes to Caffa, where Genoa had an established trading post. When it became clear that ships from the East carried the plague, Messina closed its port. The ships were forced to seek safe harbour elsewhere around the Mediterranean, and the disease was able to spread quickly. During the Medieval period the plague went by several names, the most common being "the Pestilence" and "The Great Mortality". Theories about the cause of the disease were numerous, ranging from a punishment from God to planetary alignment to evil stares. Not surprisingly, many people believed that the horrors of the Black Death signaled the Apocalypse, or end of time. Others believed that the disease was a plot by Jews to poison all of the Christian world, and many Jews were killed by panicked mobs.

Plague is caused by the bacteria Yersinia pestis. Rodents, such as rats, carry the disease. It is spread by their fleas.

People can get the plague when they are bitten by a flea that carries the plague bacteria from an infected rodent. In rare cases, you may get the disease when handling an infected animal.

plague lung infection called pneumonic plague can spread from human to human

“The Black Death” Even before the “death ships” pulled into port at Messina, many Europeans had heard rumors about a “Great Pestilence” that was carving a deadly path across the trade routes of the Near and Far East. (Early in the 1340s, the disease had struck China, India, Persia, Syria and Egypt.) However, they were scarcely equipped for the horrible reality of the Black Death. “In men and women alike,” the Italian poet Giovanni Boccaccio wrote, “at the beginning of the malady, certain swellings, either on the groin or under the armpits…waxed to the bigness of a common apple, others to the size of an egg, some more and some less, and these the vulgar named plague-boils.” Blood and pus seeped out of these strange swellings, which were followed by a host of other unpleasant symptoms–fever, chills, vomiting, diarrhea, terrible aches and pains–and then, in short order, death. The Black Death was terrifyingly, indiscriminately contagious: “the mere touching of the clothes,” wrote Boccaccio, “appeared to itself to communicate the malady to the toucher.” The disease was also terrifyingly efficient. People who were perfectly healthy when they went to bed at night could be dead by morning

he Black Death

Yellow fever and the yellowfever mosquito are thought to have originated in Africa. It was brought to the New World on slave ships in the 1500s. Yellow fever ravaged Europeans in the New World. Buckley (1985) stated, "The West Indies was, quite simply, a deathtrap for whites without immunity to yellow fever." The British were repeatedly stung by the disease in the Caribbean and South America. In 1741, during an expedition to capture Peru and Mexico, British forces were reduced from 27,000 to 7,000 by the dreaded disease they called "black vomit." Coastal towns and hamlets in the United States were particularly vulnerable to the disease in the seventeenth and eighteenth centuries. Even as late as 1878, a yellow fever epidemic struck more than 100 United States towns, killing at least 20,000 people.

Smallpox is an acute contagious disease caused by Variola virus, a memb