plagues test 1

first epidemiological transition

from foraging to food production, change in disease patterns due to change in lifestyle ex. increase in dental caries, nutritional deficiencies, infectious diseases, skeletal conditions [arthritis], and decrease in growth and height

population mortality profiles change

not linear in history, enclose both death due to infectious diseases and chronic degenerative diseases [heart disease, cancer]. impacts economically influenced and unequal in distribution developed v.s. developing countries]

decrease in morality in 19th c -20th c

improved living conditions and health of population, chemotherapy and antibiotics, reduced virulence of microbes

why emerging / re-emerging diseases?

• globalization

• anything that will change population density [war, famine, natural and man-made disasters]

• changes to environment which release undisturbed pathogens [deforestation, irrigation, dams, melting permafrost, etc.]

• social inequalities [nutrition, medical care, housing]

• adventure travel to areas with ‘new’ microbe reservoir

• synergies in disease environment [measles & TB, HIV/AIDS & TB]

syndemic perspective

idea that no disease exists in isolation & population health can be understood through a confluence of factors [climate change or social inequalities]

endemic

disease which regularly occurs

epidemic

sudden increase in disease frequency above endemic levels

pandemic

sudden increase in cases [epidemic] that spreads rapidly across several countries, continents or the world

herd immunity

collective resistance of a population to infection and spread of an infectious disease. [more immune people = less infection] cause by exposure to disease or mild infection creating immunity [vaccine]

plague elements: host

factors that influence exposure and susceptibility i.e.. immune response. state of body health wise [nutrition, other diseases, mental health]

plague elements: pathogen

how susceptible it is to antibiotics as some can adapt and override it. ability to live outside the host and reemerge later. ability to produce toxins and damage the body reducing the hosts immunity.

plague elements: ecology

The physical environment can attribute to the spread and survival of pathogens, as well as the culture, social, and political factors which influence lifestyle.

plague elements: vectors

some pathogens require living vectors to spread them to a human host ex. mosquitos and ticks

yersinia pestis

• named after one of the scientists who ID the bacteria in 1894, Alexandre Yersin

• rod shaped bacillus

• enteric bacteria family; intestinal

• diverged from Y. pseudotuberculosis 30,000 ya

• 6,000 ya evolved into a parasite requiring a host adapting to survive in fleas and propagate through their bites

• overwhelms the hosts immune system and rapidly replicates in bloodstream

• can get it from flea bite, contaminated food and scratches/bites from infected animals

y. pestis infection

bacteria gets drained into lymph nodes causing painful swelling [buboes] at the neck, armpits, and groin. bacteria can then move into the bloodstream causing septicemic plague or the lungs causing pneumonic plague. pneumonic is super contagious spreads through tiny droplets through coughing or sputum [mucus], death in 48 hours if untreated, treatable today with antibiotics.

y.pestis genome

• 1998 sequenced

• 2000 first isolated sample of ancient plague DNA

• 2011 samples from victims at London burial site yield gnome

• plague evolved slowly from past to present

• four variants split from common ancestor, circulate for the next centuries

Europe prior to the black Plague

• 10th c. warm climate [medieval climate anomaly], good for agriculture; population doubled by 13th c 60-70 M

• urban pop and wealth growth

• trade and conquest abroad identified

• merchants from Venice, genoa, and Florence involved in Eurasian trade system run by Mongol kingdoms

turn from prosperity

• 1291 last crusaders and descendants expelled from levant

• Italian trade with central Asia diminished

• 100 yrs war brought in more Europeans

• MCA ends environment gets cold and wet creating an agricultural crisis and famine, and disease outbreak in cows in oxen at 50% mortality

black plague origins

evidence that it was in central Asia for thousands of years from documents of pandemics and evidence from Tien Shan mountains of 6th c pandemic

spread of black plague

• 1346 easter edge of black sea [entered Genoese trade trade network]

• 1347 through Mediterranean via Messina

• 1348 inland to Paris and SW England

• 1349 Ireland and Iberian peninsula

• clockwise through Scandinavia

• 1353 Russia

medicine and faith black plague

church as large influence and predominate in society. medicine was based in ancient understanding of natural world [earth, air, water, fire]. humoral medicine, 4 humors out of balance cause sickness [ blood, phlegm, yellow bile, black bile] used herbs and potions to regain balance.

religion and humors

coexisted together, black plague was thought to be gods wrath over human willfulness and a test of faith, treatment was bloodletting. believed penance was needed to stop the plague [beat and whip themselves], and blamed jewish people for the plague alleging they poisoned the wells

persistence of black plague

• in Europe 1350-1650

• population dense cities and continued trade [rodent hitch hikers], ex. Istanbul

• rural bohemia and Germany had mortality as high as large cities

• military forces spread plague

black plague and quarantine

• leaders responded by restricting movement and commerce

• Dubrovnik created the maritime quarantine system, ships had to quarantine for 30 days before they were allowed on land, other Italian cities followed establishing boards of health and some expanded from 30 days to 40

quarantine and Europe

17th c system in Italian peninsula for monitoring trade conditions, if news of an out break trade was suspended and ships banned from ports. inland cities continued to refine strategies of keeping disease at bay [buildings built outside city walls to house those quarantining before they could enter the city.

disaster measures

• when disease rose up, barber surgeons, stretcher carriers, and grave diggers were hired.

• large gatherings were banned including at funerals.

• public places were disinfected with vinegar solutions

• belongings of victims fumigated or burned

• people appointed to monitor street activities or visit sick

• infected to stay home and isolate themselves

public health black plague

• outbreaks were intermittent allowing for leaders to alter strategies [outbreaks occurred in the late summer]

• ID what social groups were impacted [poorer, social problem for elites to tackle]

• efforts across Europe to curb begging, expel vagrants, impose punishment for social disorder

Ulrich Von Hutten

German humanist published his experience with the infection. erupted 1495 spread across Europe and Asian cities. he described it as black-green pustules, boils the size of acorns with secretions that had a foul stench

syphilis

french called it the evil of Naples, the Germans called it the french disease and Japanese called it canton itch, basically Labeling the disease foreign

treponema pallidum

spirochete [genus of spiral shaped bacteria] with flagella [tail] that wraps around the main body and corkscrews itself deep into tissue

t. pallidum pallidum

• sexually transmitted subspecies

• enters via genital contact [leaves a hard edged chancre appearing 2-6 weeks after contact, primary syphilis]

• secondary body develops a rash on the hands and feet and sometimes sores too

• latent syphilis no symptoms

• tertiary syphilis, 3-15yrs later; soft gummas [non cancerous growths on head and legs], neurological problems [erratic behaviour/schizophrenic], heart symptoms

t. pallidum pertenue [yaws]

• round hard swelling on skin center may form an ulcer [joint and bone pain, fatigue, new skin lesions]

• passed by skin contact among kids

• found in tropical regions of Africa and Asia

• no neurological issues

t. pallidum endemicum [bejel]

• chronic skin and tissue disease

• starts in childhood as small patches in the interior of the mouth

• raised eroding lesions on the limbs and trunk

• limited to arid regions of africa and middle east

• no neurological issues

treponema carteum [pinta]

• least severe

• endemic in Mexico, central america, and south america

• limited to skin, transmitted from skin to skin contact

• raised bumps that can become bigger [on exposed legs and arms]

• no neurological issues

tracing treponemal infections

• bacteria is fragile [difficult to isolate DNA from remains]

• look to skeletal features/expression on skull and leg bones

• remains in americas from pre-contact time suggest treponemal infections around before european contract

origin of syphilis: Columbian Hypotheis

• columbus brought it back with him from america

pre-colubian hypothesis

• present in euope prior to columbus

• miss diagnoses for other diseases [leprosy]

• skeletal evidance pre-dating columbus

unitarian hypothesis

variant of pre-columbian

advocates that treponemal disease are variants of the same infection [adaptive responses]

genetic understanding

• using bacteria samples shows slow evolution

• t. pallidum pallidum emerged 5,000- 16500 ya

• another study suggests syphilis and yaws share 99.8% of DNA

cities and the pox

large cities focused on controlling the spread and treating the pox

urban eleites fearful of growing urban poverty

those infected terrified passerby in the street stench was bad [bad air was believed to spread pox]

emergence of specialized institutions

• formal institutions for treatment

• pope leo x approved recommissioning a large hospital in Rome for pox treatment

• other Italian cities founded independent sites for treatment or set up separate wards in existing hospitals

• Germany also did this

• monasteries closed to free up funds for poor relief and health care

• was important because it was a chronic and long term ailment

early treatment

• tropical ointments containing mercury not new

• applied to skin, boiled for sick to inhale fumes goal was to purge the body of the pox by puking or burning it off

• mercury caused mouth ulcers, weakened gums [tooth loss], brain damage

• guaiac wood treatment boiled in water like tea for sick to drink, skimmed foam off top to apply to pustules directly, from the west indies, did not replace mercury treatment at all but gave relief from symptoms

girolamo fracasto of verona 1478-1553

poem using term syphilis and was applied to disease in 18th c

pox and moality

• gods punishment for lustiness

• eramus of rotterdam wrote short texts about the anxities of illicit sex with suffers

• 16th c consensus pox was spread by sex [some thought shared utensils, dirty bedsheets at inns or lingering kisses could transmit pox]

excused morality

• church and city leaders did not object to sale of sex by women to men

• evil of prostitution preferred male lust that would be uncontrolled if brothels closed

• male sex release more important then good health

• during out breaks brothels were closed

changes in society

• population growth

• short social contact

• port cities remained high in demand of sex services

• inequality, social insability, transient pop, double standards of sex and sti spread

london and the pox

• pop growth x2

• sex trade growth from young women looking for jobs

• shutdown of bathhouses and brothels dispersing workers throughout city

• used makeup and wigs to hide

tuskegee experiment

• done on poor african ameriacns

• they thought they were receiving treatment and were not alllowed to get real treatment

• was to study syphilis in nature

• was stupid because antibiotics proved to be the treatment and yet the study continued until a whistle blower

sti study guatemala

• research on guatamalans exposed to stis by the usa making them have sex with infected sex workers

• no informed consent and not all subjects received treatment

small pox virgin soil epidemic

• coined by alfred crosby

• populations previously isolated from a pathogen are immunologically unprepared for contact with new pathogen

• living along side animals exchange of mirobial agents

small pox etiology

• variola virus

• same genus that causes horsepox and cowpox

• 2 strains since 19thc

• variola major; extremly virulent 30% fatality

• variola minor; milder 1% mortaliy

• killed 300m ppl in 20th c

• late 60’s 10-15 m infected 2m died

• disease transmited from dried scabs or infected droplets spread by coughing and sneezing

small pox symptoms

• 12 day incubation

• high fever, muscle pain, headaches [virus travels to spleen, bone marrow, and lymph nodes]

• 2 week after infection; reddish spots in mouth, throat, mucous membranes, skin eruptions on face and body

• lesions turn to hard pustules with dimple in middle

• pustules dry out after 2 weeks but could merge into one painful layer of infection across a large section of the body

• 1/10 developed malignant small pox with flattened lesions

• lasting effect blindness and scars

small pox origin

• 10 ya emerged along with the flu and measles as societies became sedentary

• humans sole host

• viral mutations

• oldest genetic sample from lithuanian mummy

• mutations leading to small pox took place 100s not 1000s ya

adaptive immunity

response body develops to a pathogen

mother pass it to there kids

innate immunity

mechanisims of resisting disease that do not reflect a bodies previous exposure to a pathogen, bodies first response to injury or infection [inflamation, mucus, fever, destruction of foriegn cells and comprosised cells]

small pox in antiquity

• pockmarks on eygptian mummies 12th c BCE

• written accounts in china 250 BCE

• descriptions from arabic author Rhazes 10th c

• japan pop density higher than europe extensive record keeping 700 CE called it bean-pod pox, regular outbreaks 12th c mainly effecting kids

small pox in south america

• 15th c american pop high mortality to disease [occured when europeans encountered first]

• pop fell over decades more so than black plague

• sturctual violence of using the disease to kill indigenous communities

tenochtitlan

• Mexico valley 200,00 pop

• metropolis of aztec empire

• hernan cortes disobeys orders attacks with 1000 troops and allies of other indigenous ppl, to get more indigenous slaves for the spanish

• panfilo narvaez supposed to bring cortes back but joins him probalem brought small pox with him and his men

• mortality rate of 40% lost around 75% of pop

small pox north america

• indgenous ppl encounter french eng an dutch

• coastal ship traffic and contact with settlers

• get smallpox

• epidemic diseases accompanied by war social upheaval and ecological changes

• used as a weapon by settlers

inoculation

• vaccine proposed by edward jenner

• individuals recieved materials from a smallpox sufferer to hopefully cause mild disease and get immunity to small pox

• china they collected and dried out the scabs made a powder and had people snort it

• sutton method by rober sutton put smallpox into shallow puncture

vaccination

• jenner innoculated 8yr james phipps with cow pox after seeing milkmaid getting it milder then smallpox but getting immunity to cow pox and small pox, this wrok and he did it on other some still died

eradication of small pox

• no longer natural

• vaccination important role in this

• WHO put there minds to it and work to get vaccines to place like africa once lyophilization allowed for them to carry the vaccines without them spoiling in the heat

• air compressed guns were first used for vaccine, then bifurcated needle which was easier

• 1960, herd immunity approch targeting who ever showed signs or was incontact with someone who had it [helped in nigeria in 1966, when they didn’t have enough vaccines to get everyone]