Gina Kolata: How Pandemics End
An infectious outbreak can conclude in more
ways than one, historians say. But for whom does it end, and who gets to
decide? When will the Covid-19
pandemic end? And how? According to
historians, pandemics typically have two types of endings: the medical, which
occurs when the incidence and death rates plummet, and the social, when the
epidemic of fear about the disease wanes. “When people ask,
‘When will this end?,’ they are asking about the social ending,” said Dr.
Jeremy Greene, a historian of medicine at Johns Hopkins.
In other words, an end
can occur not because a disease has been vanquished but because people grow
tired of panic mode and learn to live with a disease. Allan Brandt, a Harvard
historian, said something similar was happening with Covid-19: “As we have seen
in the debate about opening the economy, many questions about the so-called end
are determined not by medical and public health data but by sociopolitical
processes.” Endings “are very,
very messy,” said Dora Vargha, a historian at the University of Exeter.
“Looking back, we have a weak narrative. For whom does the epidemic end, and
who gets to say?”
In the path of fear: An epidemic of fear
can occur even without an epidemic of illness. Dr. Susan Murray, of the Royal
College of Surgeons in Dublin, saw that firsthand in 2014 when she was a fellow
at a rural hospital in Ireland. In the preceding
months, more than 11,000 people in West Africa had died from Ebola, a
terrifying viral disease that was highly infectious and often fatal. The
epidemic seemed to be waning, and no cases had occurred in Ireland, but the
public fear was palpable.
“On the street and on the wards, people are
anxious,” Dr. Murray recalled recently in an article in The New England Journal of
Medicine. “Having the wrong color skin is enough to earn you the side-eye from
your fellow passengers on the bus or train. Cough once, and you will find them
shuffling away from you.” The Dublin hospital
workers were warned to prepare for the worst. They were terrified, and worried
that they lacked protective equipment. When a young man arrived in the
emergency room from a country with Ebola patients, no one wanted to go near
him; nurses hid, and doctors threatened to leave the hospital.
Dr. Murray alone dared
treat him, she wrote, but his cancer was so advanced that all she could offer
was comfort care. A few days later, tests confirmed that the man did not have
Ebola; he died an hour later. Three days afterward, the World Health
Organization declared the Ebola epidemic over. Dr. Murray wrote: “If
we are not prepared to fight fear and ignorance as actively and as thoughtfully
as we fight any other virus, it is possible that fear can do terrible harm to
vulnerable people, even in places that never see a single case of infection
during an outbreak. And a fear epidemic can have far worse consequences when
complicated by issues of race, privilege, and language.”
Black Death and
dark memories : Bubonic plague has
struck several times in the past 2,000 years, killing millions of people and
altering the course of history. Each epidemic amplified the fear that came with
the next outbreak.The disease is caused
by a strain of bacteria, Yersinia pestis, that lives on fleas that live on
rats. But bubonic plague, which became known as the Black Death, also can be
passed from infected person to infected person through respiratory droplets, so
it cannot be eradicated simply by killing rats.
Historians describe
three great waves of plague, said Mary Fissell, a historian at Johns Hopkins:
the Plague of Justinian, in the sixth century; the medieval epidemic, in the
14th century; and a pandemic that struck in the late 19th and early 20th
centuries. The medieval pandemic
began in 1331 in China. The illness, along with a civil war that was raging at
the time, killed half the population of China. From there, the plague moved
along trade routes to Europe, North Africa and the Middle East. In the years
between 1347 and 1351, it killed at least a third of the European population.
Half of the population of Siena, Italy, died.
“It is impossible for
the human tongue to recount the awful truth,” wrote the 14th-century chronicler
Agnolo di Tura. “Indeed, one who did not see such horribleness can be called
blessed.” The infected, he wrote, “swell beneath the armpits and in their
groins, and fall over while talking.” The dead were buried in pits, in piles. In Florence, wrote
Giovanni Boccaccio, “No more respect was accorded to dead people than would
nowadays be accorded to dead goats.” Some hid in their homes. Others refused to
accept the threat. Their way of coping, Boccaccio wrote, was to “drink heavily,
enjoy life to the full, go round singing and merrymaking, and gratify all of
one’s cravings when the opportunity emerged, and shrug the whole thing off as
one enormous joke.”
That pandemic ended,
but the plague recurred. One of the worst outbreaks began in China in 1855 and
spread worldwide, killing more than 12 million in India alone. Health
authorities in Bombay burned whole neighborhoods trying to rid them of the
plague. “Nobody knew if it made a difference,” the Yale historian Frank Snowden
said. It is not clear what
made the bubonic plague die down. Some scholars have argued that cold weather
killed the disease-carrying fleas, but that would not have interrupted the
spread by the respiratory route, Dr. Snowden noted.
Or perhaps it was a
change in the rats. By the 19th century, the plague was being carried not by
black rats but by brown rats, which are stronger and more vicious and more
likely to live apart from humans. “You certainly wouldn’t want one for a pet,”
Dr. Snowden said. Another hypothesis is
that the bacterium evolved to be less deadly. Or maybe actions by humans, such
as the burning of villages, helped quell the epidemic. The plague never
really went away. In the United States, infections are endemic among prairie
dogs in the Southwest and can be transmitted to people. Dr. Snowden said that
one of his friends became infected after a stay at a hotel in New Mexico. The
previous occupant of his room had a dog, which had fleas that carried the
microbe. Such cases are rare,
and can now be successfully treated with antibiotics, but any report of a case
of the plague stirs up fear.
One disease that
actually ended: Among the diseases to
have achieved a medical end is smallpox. But it is exceptional for several
reasons: There is an effective vaccine, which gives lifelong protection; the
virus, Variola major, has no animal host, so eliminating the disease in humans
meant total elimination; and its symptoms are so unusual that infection is
obvious, allowing for effective quarantines and contact tracing. But while it still
raged, smallpox was horrific. Epidemic after epidemic swept the world, for at least
3,000 years. Individuals infected with the virus developed a fever, then a rash
that turned into pus-filled spots, which became encrusted and fell off, leaving
scars. The disease killed three out of 10 of its victims, often after immense
suffering.
In 1633, an epidemic
among Native Americans “disrupted all the native communities in the northeast
and certainly facilitated English settlement in Massachusetts,” said Harvard
historian Dr. David S. Jones. William Bradford, leader of the Plymouth colony, wrote
an account of the disease in Native Americans, saying the broken pustules would
effectively glue a patient’s skin to the mat he lay on, only to be torn off.
Bradford wrote: “When they turn them, a whole side will flay off at once as it
were, and they will be all of a gore blood, most fearful to behold.” The last person to
contract smallpox naturally was Ali Maow Maalin, a hospital cook in Somalia, in
1977. He recovered, only to die of malaria in 2013.
Forgotten
influenzas: The 1918 flu is held
up today as the example of the ravages of a pandemic and the value of
quarantines and social distancing. Before it ended, the flu killed 50 million
to 100 million people worldwide. It preyed on young to middle-aged adults —
orphaning children, depriving families of breadwinners, killing troops in the
midst of World War I.
In the autumn of 1918,
Victor Vaughan, a prominent doctor, was dispatched to Camp Devens near Boston
to report on a flu that was raging there. He saw “hundreds of stalwart young
men in the uniform of their country, coming into the wards of the hospital in
groups of ten or more,” he wrote. “They are placed on the cots until every bed
is full, yet others crowd in. Their faces soon wear a bluish cast, a
distressing cough brings up blood stained sputum. In the morning the dead
bodies are stacked up in the morgue like cord wood.” The virus, he wrote,
“demonstrated the inferiority of human inventions in the destruction of human
life.”
After sweeping through
the world, that flu faded away, evolving into a variant of the more benign flu
that comes around every year. “Maybe it was like a
fire that, having burned the available and easily accessible wood, burns down,”
Dr. Snowden said. It ended socially,
too. World War I was over; people were ready for a fresh start, a new era, and
eager to put the nightmare of disease and war behind them. Until recently, the
1918 flu was largely forgotten. Other flu pandemics
followed, none so bad but all nonetheless sobering. In the Hong Kong flu of
1968, one million people died worldwide, including 100,000 in the United
States, mostly people older than 65. That virus still circulates as a seasonal
flu, and its initial path of destruction — and the fear that went with it — is
rarely recalled.
How will Covid-19
end? : Will that happen with
Covid-19? One possibility,
historians say, is that the coronavirus pandemic could end socially before it
ends medically. People may grow so tired of the restrictions that they declare
the pandemic over, even as the virus continues to smolder in the population and
before a vaccine or effective treatment is found. “I think there is this
sort of social psychological issue of exhaustion and frustration,” the Yale
historian Naomi Rogers said. “We may be in a moment when people are just saying:
‘That’s enough. I deserve to be able to return to my regular life.’”
It is happening
already; in some states, governors have lifted restrictions, allowing hair
salons, nail salons and gyms to reopen, in defiance of warnings by public
health officials that such steps are premature. As the economic catastrophe
wreaked by the lockdowns grows, more and more people may be ready to say
“enough.” “There is this sort of
conflict now,” Dr. Rogers said. Public health officials have a medical end in
sight, but some members of the public see a social end.
“Who gets to claim the
end?” Dr. Rogers said. “If you push back against the notion of its ending, what
are you pushing back against? What are you claiming when you say, ‘No, it is
not ending.’” The challenge, Dr. Brandt
said, is that there will be no sudden victory. Trying to define the end of the
epidemic “will be a long and difficult process.”
