The Most Lethal of Strangers Filovirus A Lethal Stranger Ebola belongs to a group of viruses known as filoviruses because of their long filamentous structure Bats and flying mammals are the presumes hosts Humans primates are a dead end host for filoviruses where the mortality rate ranges from 90 100 Unlike the familiar enemies of humans Streptococcus and Salmonella making us sick and move on to other hosts Filoviruses like Ebola come from other species swiftly invade wreak devastation and die with their victims Legionella The Accidental Pathogen Legionella pneumophila is the cause of Legionnaire s Disease a bacterial pneumonia afflicting the elderly This bacterium normally lives in fresh water lakes and ponds as a parasite of amoeba After being consumes this microbe turns the tables and instead of being eaten consumes the amoeba When water contaminated with amoeba contacts people in the form of showers or air conditioning the Legionella bacterium uses the same tools that help it multiply inside amoebae to grow inside human lung cells The result is a potentially lethal pneumonia of its accidental human host Feudal Death The Black Plague In 1347 bubonic plague carried by infected crusaders returning from the Middle East struck France Italy and spread through Europe Helpless doctors could only watch as the plague took at least 40 million lives a quarter of Europe s population in six years Jewish communities were perceived to not be as severely plague stricken and many from those communities were accused of spreading plague and hanged or burned alive Despair chaos and economic upheaval caused a profound loss of faith in Europe s feudal institutions It took Europe over a century to recover its population Labor was in short supply and land abundant Wages for farm labor were instituted accelerating the decline of feudalism and the birth of the renaissance Hernando Cortes and Francisco Pizarro conquered Central and South America with small armies thanks to smallpox Early Spanish explorers introduced the virus to the immune naive native people and engendered the fall of two major civilizations Millions in the Incan and Aztec empires fell to smallpox as did their god kings rulers Smallpox as Bioweapon During the Siege of Fort Pitt during the French Indian war British general Jeffrey Amherst ordered blankets and handkerchiefs contaminated with smallpox to fall into the hands of the native warriors laying siege to the fort in order to reduce native threat Smallpox and the American Revolution Native Americans and African slaves were much more susceptible to morbidity and mortality from smallpox than the Europeans spreading it to the new world Many first and second generation American colonists were also susceptible Illness due to smallpox may have contributed to the first losses of American Revolutionary forces against the British Later colonists confounded the British Army by sending susceptible loyalists slaves to catch smallpox and become ill themselves overwhelming British Army medical supplies and physicians Variolation and Vaccination The Chinese processed dried scabs from smallpox suffers into a powder which they inhaled to protect them from smallpox Protection by this method was inconsistent so the dried scabs were introduced under the skin in a process called variolation The disease caused by variolation was not life threatening less scarring and provided complete immunity This process protected soldiers and civilians until Edward Jenner discovered milkmaids suffered from a mild cow pox and never from smallpox Jenner used cow pox scabs as the first protective smallpox vaccination Vacca is Latin for cow Overview Ebola virus normally found in flying mammals kills more than 90 of humans it infects Legionella bacteria normally grow in protozoan s engendering Legionnaire s disease in human lungs exposed to aerosols full of protozoan s containing the bacterium Plague bacteria bacteria normally grow in protozoan s engendering Legionnaire s disease in human lungs exposed to aerosols full of protozoan s containing the bacterium Plague bacteria Yersinia lie in rodents and can spread to humans via fleas Pneumonic plague spreads from person to person Plague bacteria killed 25 33 of Europe s population in the middle ages Plague changed the social and economic structure of Europe gendering the Renaissance Smallpox virus helped the Spanish to conquer the Aztec and Incan empires and influenced American Revolution Protection from smallpox by the practice of variolation preceded Jenner s use of cowpox virus to prevent smallpox by vaccination