Showing posts with label Black death. Show all posts
Showing posts with label Black death. Show all posts

Wednesday, April 1, 2020

The Major Pandemics thru History


The Plague of Athens was an epidemic that devastated the city of Athens during the second year of the Peloponnesian War in 430 BC. The plague returned twice more and killed 25% of the Athenian populationThe epidemic caused a massive migration from the Attic countryside into the city and resulted into an overpopulation. Due to the close quarters and poor hygiene, Athens proper became a breeding ground for the Plague and many citizens died, including the statesman  Pericles, Aspasia his wife, and his two sons.  

Some 30 pathogens have been implicated as having caused the plague but the most likely microbe according to Professor Durack of the University of Maryland was due to Rickettsial bacteria that can cause three different varieties of the disease we call typhus. According to historian Thucydides, the Athenian Plague came from Africa, Ebola and other hemorrhagic fever diseases are other distinct possibilities. (The Plague of Athens, paintng of Michiel Sweets c 1652-1654) 
In the year 541 AD, the Justinian Plague, spread thru most of the Byzantine Empire, and Western Europe including England and Ireland.  The pandemic that reappear several times until 750 AD resulted in the death of 25 to 100 million people a toll that represented 50% of Europe’s population in the first outbreak.  In 2013, researchers confirmed that the cause of the Justinian Plague was Yersinia pestis, the same bacterium responsible for the Black Death. 
The Black Death, also known as the Pestilence, the Great Bubonic Plague or the Plague, was the most devastating pandemic recorded in human history, resulting in the deaths of an estimated 200 million people in Eurasia, peaking in Europe from 1347 to 1351. The bacterium Yersinia Pestis which is known to cause several forms of the Plague such as the bubonic which is the most common, the pneumonic and others, is believed to have been the cause. 
The Black Death probably originated in Central Asia and via the Silk Road reached Crimea by 1343. From there, it was likely carried by the fleas living on rats that traveled on Genoese  merchant ships, spreading the Black Death throughout the Mediterranean Basin, and reaching the rest of Europe via the Italian Peninsula.  The plague arrived in Europe in October 1347, on 12 ships that docked at the port of Messina. People at the docks were met with a horrifying surprise: Most sailors aboard the ships were dead, and those still alive were gravely ill and covered in black boils that oozed blood and pus.  
The Black Death is estimated to have killed 30% to 60% of Europe's population.  In total, the plague may have reduced the world population from an estimated 475 million to 375 million in the 14th century. It took 200 years for Europe's population to recover to its previous level There were three more outbreaks of the plague in the 17th, 18th and 19th centuries that claimed an additional 15 million lives.  
The arrival of European conquerors and later immigrants into the Americas introduced new diseases to the indigenous populations who had no immunity to them.  As early as 1492 and later in 1836 through 1840 smallpox epidemics occurred.  Smallpox reached its height after the spring of 1837 when the steamboat, S.S. St. Peter, carried infected people and supplies into the Missouri Valley.  The death toll during the epidemic was approximately 17,000 people.  In the span of two years the Mandan Indian tribe was totally decimated.  During the epidemic white settlers and the army allegedly facilitated the spread of smallpox among unsuspecting Native Americans by giving them blankets that smallpox patients had used.  Although not scientifically documented it is likely one of the many genocides in human history. 
The Spanish flu an unusually deadly influenza pandemic lasted from January 1918 to December 1920.  It infected 500 million people—about a quarter of the world's population at the time and its death toll is estimated to have been anywhere from 17 million to 50 million.  WWI military censorship minimised reports of deaths among populations of waring nations while they were free to report from neutral Spain thus their stories created the false impression that Spain was the place the flu originated from and giving rise to the pandemic’s nickname Spanish flu.  A recent paper describes that the cities which were mostly affected by the flu experienced an economic decline with an 18% reduction of their economic output.  They authors suggest that the cities which intervened earlier and aggressively grew faster after the pandemic was over. 
(Soldiers with Spanish flu at hospital ward at Camp Funston)
Since its beginning in December 2019 in Wuhan city, in Hubei province of China, nearly 860,000 cases and 42,000 deaths due to Corona virus have been reported worldwide.  During this period, confirmed cases in select countries, are as listed in round numbers; US 190,000, Italy 105,000, China 82,000, Germany 71,000, France 52,000, Sweden 4,500, Greece 1,300, S. Korea 9,900 and Japan 2,000.  For those who are interested in a more detailed analysis please check the link Radiology Monthly but briefly as of today the death per million in the USA is 12, Italy’s is off the scale at 200, Germany’s is 10, Sweden’s is 18, Greece’s is 5, S. Korea’s is 3 and Japan’s is 0.5 which is remarkably low.  Most of the countries have instituted lockdowns, the Swedes and the Japanese are using social distancing and have not changed their way of living comparing to that before the pandemic. The Koreans and the Singaporeans are doing extensive testing.  The Taiwanese are advising hygienic measures with excellent results.  Those interested in more information about pandemics of the past two millennia please consult the following link.

Sunday, March 1, 2020

Corona virus

Some maybe wondering why I post about the Coronavirus in a blog devoted primarily to traveling.  Because viruses travel along with humans.  The reason they named the novel virus Corona virus is because under electron microscopy it looks like the crown royals wear.  Corona viruses and Rhinoviruses are the etiologic factors of common cold.  Most of the colds in the winter are due to Corona viruses while those in early fall, spring and summer are due to Rhinoviruses.   The novel Corona virus was recently renamed to Covid-19 belongs in the family of viruses that humans and other mammals harbor in our bodies. 
Covid-19 emerged in Hubei province in central China in late December 2019 and subsequently spread in 59 countries around the world.  As of March 6, 2020 at 12:15 UCT/GMT the World Health Organization (WHO) reported 100,242 infections and 3,408 deaths.  China the epicenter of the epidemic has reported 80,559 infections and 3,042 deaths.  South Korea has reported 6,593 cases and 42 deaths while Iran is next with 4,747 cases and 124 deaths and Italy follows with 3,858 cases and 148 deaths. The overall death rate is 3.4% but this is not an accurate estimate as it does not take into account the mild or asymptomatic cases that are not recorded.

Interestingly according to the Centers for Disease Control and Prevention (CDC) there have been 30-40 million million flu cases, and between 15-40,000 deaths in the 2019-2020 flu season in the USA alone, a disease that can be prevented but individuals decide not to get vaccinated to their and other people peril.  
The most common symptoms of Covid-19 infection are fever, headache and coughing as the virus tend to affect the lungs.  
Although it is impossible to avoid completely exposure in an epidemic there are several precautionary measures that people should take such as covering their nose and mouth when sneezing or coughing.
The simplest and most effective measure in the dissemination of the virus is washing hands with soap and water if we believe we’ve touched surfaces contaminated by nasal excretions. 
Wearing masks is a sensible way to prevent exposing others and maybe avoid viral exposure to ourselves.  Other reasonable precautions are avoiding contact with live animals that are known to harbor the virus such as bats, and finally avoiding eating uncooked meat. 
As in every epidemic people should exercise reasonable precautions while in the same time excessive measures should be avoided.  We should remember that similar epidemics have taken place in the past.  The MERS viral epidemic had a mortality rate of 10% while the SARS had a mortality rate of 5%.  The Corona virus mortality is estimated to be between 1-2%.  (Doctor Schnabel of Rome, is coper engraving by Paulus Fürst of a plague doctor in 1656)
Needless to say, that the mortality rate of the above-mentioned epidemics was negligible when is compared with the Plague or Black Death which is estimated to have killed 25 million individuals that represented one third of Europe’s population. The plague may have reduced the world population from an estimated 475 million to 350–375 million in the 14th century(Image Saint Sebastian interceding to God for the Plague stricken. By Josse Lieferinxe exhibited at The Walter’s Art Gallery, Baltimore, Maryland, USA)