DEADLY GERMS, LOST CURES
This sacred river offers clues to the spread
of one of the world’s most daunting health problems: germs impervious to common
medicines
By
Donald G. McNeil Jr.
 |
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Deepak
K. Prasad, left, collected a water sample, while Rishabh Shukla, right,
checked
the temperature of the Ganges at Byasi, India, in the Himalayas.
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GANGOTRI,
India — High in the
Himalayas, it’s easy to see why the Ganges River is considered sacred.
According to Hindu legend, the Milky Way
became this earthly body of water to wash away humanity’s sins. As it drains
out of a glacier here, rock silt dyes the ice-cold torrent an opaque gray, but
biologically, the river is pristine — free of bacteria.
Then, long before it flows past any big
cities, hospitals, factories or farms, its purity degrades. It becomes filled
with a virulent type of bacteria, resistant to common antibiotics.
The Ganges is living proof that
antibiotic-resistant bacteria are almost everywhere. The river offers powerful
insight into the prevalence and spread of drug-resistant infections, one of the
world’s most pressing public health problems. Its waters provide clues to how
these pathogens find their way into our ecosystem.
Winding over 1,500 miles to the Bay of
Bengal, Ma Ganga — “Mother Ganges”— eventually becomes one of the planet’s most
polluted rivers, a mélange of urban sewage, animal waste, pesticides,
fertilizers, industrial metals and rivulets of ashes from cremated bodies.
But annual tests by scientists at the Indian
Institute of Technology show that antibiotic-resistant bacteria appear while
the river is still flowing through the narrow gorges of the Himalayan
foothills, hundreds of miles before it encounters any of the usual suspects
that would pollute its waters with resistant germs.
The bacterial levels are “astronomically
high,” said Dr. Shaikh Ziauddin Ahammad, a professor of biochemical engineering
at the Indian Institute of Technology. The only possible source is humans,
specifically the throngs of ritual bathers who come to wash away their sins and
immerse themselves in the waters.
India’s
resistance problem
Beyond the Ganges, India has some of the
highest antibiotic-resistance rates in the world, according to a 2017 report
from the government’s Ministry of Science and Technology.
Tests showed that about 70 percent of four
bacteria species commonly found in hospital patients were resistant to typical
first-line antibiotics. Between 12 percent and 71 percent — depending on the
species tested — were also resistant to carbapenems, a class of antibiotics
once considered the last line of defense.
Other studies confirm the danger. An article
in Lancet Infectious Diseases found that about 57 percent of infections in
India with Klebsiella pneumoniae, a common bacterium, were carbapenem-resistant.
But where exactly do these armies of
drug-resistant germs come from? Are they already everywhere — in the soil
beneath our feet, for example? Do they emerge in hospitals, where antibiotics
are heavily used?
Are they bred in the intestines of livestock
on factory farms? Do they arise in the fish, plants or plankton living in lakes
downstream from pharmaceutical factories?
Or are the germs just sitting inside the
patients themselves, waiting for their hosts to weaken enough for them to take
over?
Research now being done in India and
elsewhere suggests an answer to these questions: Yes, all of the above.
But how drug-resistant bacteria jump from one
human to another outside of a hospital setting is the least-understood part of
the process, and that is why the findings from the Ganges are so valuable.
Origins
of drug-resistant germs
Antibiotic-resistance genes are not new. They
are nearly as old as life itself.
On a planet that is about 4.5 billion years
old, bacteria appeared about 3.8 billion years ago. As they fed on one other —
and later on molds, fungi, plants and animals — their victims evolved genes to
make bacteria-killing proteins or toxins, nature’s antibiotics. (Penicillin,
for example, was discovered growing in mold.)
The bacteria, in turn, evolved defenses to
negate those antibiotics. What modern medicine has done, scientists say, is put
constant Darwinian pressure on bacteria.
Outside the body, they face sunlight, soap,
heat, bleach, alcohol and iodine. Inside, they face multiple rounds of
antibiotics. Only the ones that can evolve drug-resistance genes — or grab them
from a nearby species, which some bacteria can do — will survive.
The result is a global bout of sudden-death
elimination at a microscopic level. Bacteria once susceptible to all families
of antibiotics have become resistant to penicillins, then tetracyclines, then
cephalosporins, then fluoroquinolones — and so on, until nearly nothing works
against them.
“When bacteria are stressed, they turn on
their S.O.S. system,” said David W. Graham, a professor of ecosystems
engineering at Newcastle University in Britain and a pioneer in
antibiotic-resistance testing. “It accelerates the rate at which they rearrange
their genes and pick up new ones.”
Eight years ago, Dr. Ahammad, a former
student of Dr. Graham, suggested testing Indian waters.
“Until then,” Dr. Graham said, “I had avoided
India because I thought it was one huge polluted mess.” With
antibiotic-resistant bacteria so ubiquitous, it would be hard to design a good
experiment — one with a “control,” someplace relatively bacteria-free.
“We needed to find some place with clear
differences between polluted and unpolluted areas,” Dr. Graham said.
That turned out to be the Ganges.
Healthy
pilgrims, dangerous germs
Although it is officially sacred, the Ganges
is also a vital, working river. Its numerous watersheds in the mountains,
across the Deccan Plateau and its vast delta serve 400 million people — a third
of India’s population — as a source of drinking water for humans and animals,
essential for crop irrigation, travel and fishing.
Twice a year, two of Dr. Ahammad’s doctoral
students, Deepak K. Prasad and Rishabh Shukla, take samples along the whole
river, from Gangotri to the sea, and test them for organisms with
drug-resistance genes.
The high levels discovered in the river’s
lower stretches were no surprise. But the researchers found bacteria with
resistance genes even in the river’s first 100 miles, after it leaves Gangotri
and flows past the next cities downstream: Uttarkashi, Rishikesh and Haridwar.
More important, the researchers found that
the levels were consistently low in winter and then surged during the
pilgrimage season, May and June.
Tiny Gangotri is so high in the mountains
that it closes in winter, made impassable by the snow. But in summer, the area’s
population swells with hundreds of thousands of pilgrims.
Because the district is sacred, no alcohol or
meat may be sold there. Devout Hindus are often vegetarian and abstemious.
The riverside cities have wide flights of
steps, called ghats, leading into the water, often with netting or guardrails.
They help pilgrims safely immerse themselves and drink — a ritual that is
supposed to wash away sins and hasten entry into paradise.
Souvenir stands sell plastic jugs so pilgrims
can take Ganges water home to share.
The most famous of the Upper Ganges
pilgrimage cities is Rishikesh. Its streets are lined with hotels with names
like Holy River and Aloha on the Ganges. Besides pilgrims, Westerners pour in
for the town’s annual yoga festival or to study in its many ashrams and
ayurvedic medicine institutes.
In 1968, the Beatles studied Transcendental
Meditation there with the Maharishi Mahesh Yogi. In his pre-Apple days, Steve
Jobs pursued enlightenment there. Prince Charles and Camilla Parker-Bowles have
visited.
Adventure tourists also travel there.
Rishikesh offers river-rafting, mountain trekking, zip lines and paintball
tournaments.
The population is about 100,000 in winter,
but in the pilgrimage-vacation season it can swell to 500,000. The city’s
sewage treatment plant can handle the waste of only 78,000 people, Dr. Ahammad
said. The government deploys many portable toilets, but the slightest rainstorm
can send sewage cascading into the river.
In 2014, Dr. Graham and Dr. Ahammad found the
clean-versus-dirty line in the Ganges to be at its starkest at Rishikesh.
Upstream, the water was fairly clean both
summer and winter, but downstream in summer, the levels of bacteria with
drug-resistance genes were astounding. The levels of NDM-1 — a drug-resistance
gene that was first discovered in India and whose first two initials stand for
New Delhi — were 20 times higher.
That finding has led the researchers to
several conclusions. The resistant bacteria in the water had to have come from
people — specifically, from their intestines.
Perhaps more intriguing, those people were
fairly healthy — most were hale and hearty enough to be pilgrims, yoga students
or river-rafters.
Presumably, Dr. Ahammad and Dr. Graham
explained, the healthy travelers “bad” gut flora were held in check by their
“good” flora.
At least 1,000 bacterial species have been
found colonizing human intestines. A healthy individual has at least 150
species, all competing with one another for space and food.
People can shed the bacteria they carry into
the Ganges, Dr. Ahammad’s and Dr. Graham’s research shows. Then, if someone
else picks them up, then falls ill and is given antibiotics, the person’s good
bacteria can be killed and the bad ones have an opportunity to take over.
Pilgrimage areas, Dr. Ahammad and Dr. Graham
wrote, are “potential hot spots for antibiotic-resistance transmission at large
scales.”
“We are not telling people to stop rituals
they’ve done for thousands of years,” Dr. Ahammad said. “But the government
should do more to control the pollution and protect them.”
What will be required, he said, is an Indian
equivalent of the Clean Water Act, which provided billions of federal dollars
to build hundreds of sewage treatment plants across the United States.
And even that, he explained, would not be
enough. While tertiary sewage treatment can kill or remove resistant bacteria,
it doesn’t destroy free-floating DNA.
“That technology hasn’t been invented yet,”
said Mr. Shukla, who is working to invent it.
A
continuing risk
In the meantime, pilgrims will continue to be
at risk, trusting in the gods to protect them.
“Ganga is our mother — drinking her water is
our fate,” said Jairam Bhai, a large, jovial 65-year-old food vendor who held
two small jugs as he waited to descend into the water in Gangotri. “If you have
faith, you are safe.”
“We don’t follow bacteria, we don’t think
about it,” added Jagdish Vaishnav, a 30-year-old English teacher who said he
swam and drank the water in Rishikesh, Haridwar and even in Varanasi, where
torrents of raw sewage can be seen flowing into the river.
Devout Hindus go there to die so that they
can be cremated on the ghats or on floating rafts and have their ashes can be
strewn on the water to free them from the cycle of death and rebirth.
Up high in Gangotri, the priests on the banks
say they are well aware of the dangers downstream.
“Below Haridwar, I believe there are chances
of disease,” said Basudev Semwal, 50. “That’s why we publicize that people
should come here — because it’s cleaner.”
His companion, Suraj Semwal, 44, said the
government should do more. If all Hindu religious figures could get together,
they might be able to demand a cleanup, he said. But the many Hindu religious
orders are not hierarchical like those of Roman Catholicism, which has a Pope.
“Everyone has their own voice, so they can’t
speak together,” he said.
In Canada, he said he had heard, “There is a
river where you can get fined if you even touch it — and it’s just a river, not
holy at all. Here we have a holy river, and it’s very dirty and nothing is
being done.”
