Lecture 3: Plague the disease that shaped historysjryan/PPP/lectures/Lecture 3.pdf · Lecture 3:...
Transcript of Lecture 3: Plague the disease that shaped historysjryan/PPP/lectures/Lecture 3.pdf · Lecture 3:...
The Great Plague in Constantinople (542 CE)
extract from Book II, chs. xxii-xxiv History of the Wars
by Procopius of Caesarea (c. 500 -560 CE)
Anno Domini 542. During these times there was a pestilence, by which the whole human race came near to being annihilated.
Now in the case of all other scourges sent from Heaven, some explanation of a cause might be given by daring men, such as the many theories propounded by those who are clever in these matters; for they love to conjure up causes which are absolutely incomprehensible to man, and to fabricate outlandish theories of natural philosophy knowing well that they are saying nothing sound but considering it sufficient for them, if they completely deceive by their argument some of those whom they meet and persuade them to their view. But for this calamity it is quite impossible either to express in words or to conceive in thought any explanation, except indeed to refer it to God.
It did not come in a part of the world, nor upon certain men, nor did it confine itself to any season of the year, so that from such circumstances it might be possible to find subtle explanations of a cause, but it embraced the entire world, and blighted the lives of all men, though differing from one another in the most marked degree, respecting neither sex nor age.
Did plague cause the Roman Empire
essentially to end?
Political and economic instability
already
Byzantine ‘golden age’ and Antiquity
was rendered powerless
Led to the Dark Ages of pre-modern
Europe
Boccacio’s Decameron
Florence – Boccacio lived through the 1348 Black death and described the plague society as a ‘loosening’
Of women’s morals
Of the social fabric of Florence
Camus’ Plague (1947)
La Peste – story of an Algerian port, Oran, suffering from an epidemic of bubonic plague. Quarantined, it becomes a prison of death and disease.
Plague is an analogy for other political and spiritual disease of the time
Characters respond differently to the events
The concept of a plague
Plague vs. plagues – not all caused by plague,
historically
Conjures up imagery of something devastating
No selective properties – universal illness
Pandemic, lethal and horrific
Yersinia pestis
Identified by Alexander
Yersin (1894)
Gram negative bacterium
coccobacillus
Enterobacteriaceae
“safety pin” appearance
Most lethal bacterium known to mankind
WHO internationally notifiable diseases:
1. cholera
2. yellow fever
3. plague
• Plague, caused by Y. pestis, is the quintescential ‘pestilence’
• Main human forms:
– Bubonic is characterized by hemorrhaging lymph nodes which make big bumps
• Buboes – from the Greek bubo for groin
– Septacemic
• True ‘Black Death’
– Pnuemonic
• passed from human to human in droplet form (aerosol)
Ways to die from plague
#1 - BUBONIC
Flea-borne
Lymph nodes
Buboes
50 – 60% mortality rate (untreated)
• Pupuric plague – pupura (Latin) meaning
purple. Skin shows purple and red spots due
to subcutaneous bleeding.
• Extremities get severe septacemia and
gangrene, going black, hence Black Death
Ways to die from plague
#2 - SEPTICAEMIC
– from contact with infected tissues
– Mortality rate if untreated approaches 100%
#3 - PNEUMONIC
Bubonic becomes secondary pneumonic
Secondary pneumonic becomes primary
pneumonic
Sputum makes it highly contagious
Almost 100% fatal
Approximately 12% of cases of bubonic and primarysepticemic plague develop into secondary pneumonic plague.
So, approximately 1 in 10 chance of an out-of-control human-human epidemic
SCARY.
Flea-borne zoonotic disease
Fleas
(Insecta; Siphonaptera)
Flea transmission discovered by Simond (1898)
Yersinia pestis
Image: Xenopsylla chepsis (oriental rat flea) engorged with blood
Source: CDC Division of Vector-borne Infectious Disease
Primary vector of plague in most large plague epidemics in Asia, Africa, and South America.
Both male and female fleas can transmit the infection.
Wild or urban rodents maintain a reservoir
of Y. pestis that is transmitted by fleas -
sylvatic plague and urban plague
Humans are essentially an ‘accidental’ host
in a rodent epidemic
• Plague or black death is an infection of rodents
caused by Yersinia pestis and accidentially
transmitted to humans by the bite of infected fleas.
• The disease follows urban and sylvatic cycles and
is manifested in bubonic and pneumonic forms
How do the fleas actually transmit it?
Blocking fleas
1. Plague multiply in proventriculus (foregut)
2. Biofilm obstructs blood from midgut
3. Flea starves
4. Repeated biting
5. Regurgitation of bacteria
6. Flea dies
Increased
transmission
Blocking fleasClassic case:
Black rats and rat flea (Xenopsylla cheopis)
Plague multiply in proventriculus
Is it true?
Early-phase transmission can occur
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1 2 3 4 5 6 7 8 9 10
Days after flea infection
Tra
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Transmission begins
Early-phase transmission
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Time to blocking
Transmission begins
Traditional ‘blocking’ mechanism
Evolutionary origin of plague
• Soil
• Relatives (abdominal pain):
– Yersinia pseudotuberculosis
– Yersinia enterocolitica
• Adopted plasmids
• Central Asia (Steppes)
Pandemic #1: Justinian
• 6th century – Justinian plague
– Est. 100 million lives across Old World
– Supposedly started in 542 due to trade routes from a
small island
– More likely came through Egypt
• Largely restricted to Mediterranean coast
• Variant: ANTIQUA
• Still found in Africa & Central Asia
• Byzantine historian Procopius wrote that plague was killing 10,000 people in Constantinople every day
• Emperor Justinian I created new legislation to deal with inheritance suits resulting from plague deaths
• Justinian spent huge amounts of money for wars against the Vandals in Carthage and the Ostrogoths of Italy, and to build the Hagia Sophia
• Ultimately Italy fractured, Arabs won land wars, and the Western Roman Empire didn’t exist
• Long term effects on European and Christian history
Pandemic #2: The Black DeathThe Black DeathThe Black DeathThe Black Death
First, out of the blue, a kind of chilly stiffness troubled their bodies.
They felt a tingling sensation, as if they were being pricked by the
points of arrows.
The next stage was a fearsome attack which took the form of an
extremely hard, solid boil. In some people this developed under the
armpit and in others in the groin. As it grew more solid, its burning
heat caused the patients to fall into an acute and putrid fever, with
severe headaches. In some cases it gave rise to an intolerable stench.
In others it brought vomiting of blood. There was no known remedy
for the vomiting of blood. But from the fever it was sometimes
possible to make a recovery.
- de’ Mussis, French abbott, 1348
The Black DeathThe Black DeathThe Black DeathThe Black Death
Europe; 1347 – 1351
17 – 28 million deaths
(30 – 40% population)
Variant: MEDIEVALIS
Destruction of European feudal system
Intermittent outbreaks for 300 years
1665 Great Plague of London - 100,000 died
1666 “Great Fire” of London as disinfection –
70,000 of 80,000 homes destroyed
Newton fled London & invented ‘Calculus’
The Black DeathThe Black DeathThe Black DeathThe Black Death
The Black DeathThe Black DeathThe Black DeathThe Black Death
• The Black Death was one of the great epidemic scourges of mankind.
• It swept across Europe and Asia in a series of devastating pandemics during the Middle Ages.
• This disease was responsible for the death of one-third of the world's population at that time.
• Truly depressing for people – seen as inexplicable punishment – by GOD
• Christians blamed the Jews
– Tended to live in separate areas, thus initially appeared not to catch it
• Fear is useful for power and propaganda…
It might not have been – records from earlier
suggest upto 1/3 of population were dead
around the mediterranean 6th century
Ecological explanation – transmission may
have been more efficient (next slide)
Why was Black Death worse than
Justinian Pandemic?
Pandemic #3: Third Pandemic
• Yunan Province, China, 1855 – outbreak
– Muslim rebellion caused refugees to flee south
• Canton and Hong Kong, 1894
– 60,000 dead in a few weeks, 100,000 in 2 months
• Followed the shipping routes to all continents
– Ultimately killed 12 million in India and China
• Endemic in Hong Kong until 1929
• Variant: ORIENTALIS
• Rat-borne and rat fleas
Arrival in Chinatown,
San Francisco
• 1900 – Chinese Year of the Rat
– March 6 – dead man with buboes, quarantine ring in
Chinatown
– Samples taken and injected into rat, 2 guinea pigs, and a
monkey (Angel Island)
– March 10 – Chinatown quarantine lifted
– March 12 – 1 dead rat, 2 dead guinea pigs
– March 13 – 1 dead monkey
– Racism, commerce and public health…
• In the United States, the last urban plague
epidemic occurred in Los Angeles in 1924-25.
• In 2002 two residents of New York City acquired
plague from New Mexico.
• What’s going on here?
But did plague really arrive in the USA
in 1900?
• Has plague been in North America for a long time?
• Was monitoring fast enough?
• Does it matter?
Risks
• Rodent – flea relationships
– Fleas (263 species, 223 host-specific)
– Rodent hosts (217 species)
• Biological warfare?
Biological warfare and plague
• Pros: Man-to-man spread, deadly
• Cons: spread, antibiotics, loss of virulence, delivery
• Catapaulting corpses
• Japan bombed China with plague fleas
– Unit 731 in WWII
– Wheat and fleas dropped by air
• Genetic engineering for antibiotic resistance?
Avoiding it
(like the plague…)
• Awareness – seasonal and sporadic outbreaks
• Watch your pets.
• Sanitation (reduce rodent proximity) –
food/wood-piles etc
• Avoid human corpse catapaults and
bioterrorists
Controlling plague - management
• Sanitation
– Keep away fleas
– Don’t live with rodents
• There’s a reason people freak out about mice/rats
• Early detection, early response
• Treatment for individual patients
• Quarantine
GOOD BOOKS:
Plague – Wendy Orent; History of plague and biological warfare
The Barbary Plague – Marilyn Chase; Plague in San Francisco
FOR GENERAL REVIEWS:
Gage, K. L., and M. Y. Kosoy. 2005. Natural history of the plague: perspectives from
more than a century of research. Annual Review of Entomology 50:505-528.
Stenseth et al. 2008. Plague: past,present, and future. PLOS Medicine 5
FLEA-BLOCKING:
Eisen et al. 2006. Early-phase transmission of Yersinia pestis by unblocked fleas as a
mechanism explaining rapidly spreading plague epizootics. Proceedings of the National
Academy of Sciences, USA 103:15380-15385.
(THANKS TO DAN SALKELD FOR A LOT OF THESE SLIDES AND MATERIAL!!)