The New York Times - 06.08.2019

TUESDAY, AUGUST 6, 2019D1

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SCIENCE MEDICINE TECHNOLOGY HEALTH

6 AGING

Hormonal changes

are only one reason

a woman’s sex life

may decline with age.

5 ARCHAEOLOGY

Rethinking Mayan

warfare in the first

century using

hieroglyphs.

In hospitals around the world, the snakelike

duodenoscope is regarded as an indispens-

able tool for diagnosing and treating dis-

eases of the pancreas and bile ducts.

But these fiber-optic devices have a re-

markable drawback: Although they are in-

serted into the upper part of the small intes-

tine through the mouth and constantly

reused, they cannot be sterilized by the usu-

al methods.

Instead, they are hand-scrubbed and

then put through dishwasher-like machines

that use chemicals to kill microorganisms.

Even when cleaned as instructed, the de-

vices may still retain bacteria that can be

transmitted to patients.

As a result, duodenoscopes have sick-

ened hundreds of patients in hospitals in the

United States and Europe. Recent testing

now suggests regulators severely under-

estimated the risks. Worse, the devices

have been shown to be capable of transmit-

ting antibiotic-resistant infections that are

almost impossible to cure.

Alarmed medical experts are urging the

Food and Drug Administration to force the

manufacturers to develop scopes that can

be properly sterilized — or to take all duo-

denoscopes off the market.

“The infection data are overwhelming

and irrefutable, and the need is urgent,”

William A. Rutala, the director of the state-

wide program for infection control and epi-

demiology at the University of North Car-

olina, said in an email.

Recent tests performed by the manufac-

turers at the demand of the F.D.A. found

that one in 20 duodenoscopes retained dis-

ease-causing microbes like E. coli even af-

ter proper cleaning.

The agency had expected that fewer than

one in 200 would retain bacteria after clean-

ing. Dr. David Jay Weber, medical director

of the statewide program at U.N.C., said the

finding was “astounding,” and called on the

F.D.A. to set a deadline for manufacturers to

fix the problem.

“Would you go on an airplane if the pilot

said, ‘By the way, there is a 5 percent chance

Devices That Are Hard to Sterilize

Duodenoscopes are inserted in

500,000 patients each year.

Some people are getting sick.

By RONI CARYN RABIN

CONTINUED ON PAGE D4

LAST SUMMER,not long after releasing a pi-

oneer pack of 14 African wild dogs into Mo-

zambique’s Gorongosa National Park as

part of an ambitious wildlife restoration ef-

fort, Paola Bouley went to see for herself

what in the name of Canis major could have

happened to the wild dog pups.

As Gorongosa’s carnivore expert, Ms.

Bouley knew that Beira, the alpha female of

the pack, had been pregnant when the dogs

were set free. She knew that the closely

bonded and highly endangered apex preda-

tors had dug a maternity den for their

queen, and that Beira had spent a lot of time

down there — until one day, she didn’t. She

and the pack had moved on.

But where were the pups?

As Ms. Bouley was crouching by the

abandoned den and peering into the hole,

she met the likely answer. A giant African

rock python — the continent’s largest

species of snake — dropped from a tree,

stared her in the face and slithered off.

“I think it was disappointed that I wasn’t

a warthog,” Ms. Bouley said.

For a snake that can grow to 20 feet and

swallow an impala whole, even a large litter

of Lycaon pictus pups would barely rate as

an amuse-bouche.

Yet the wild dogs were unbowed, and this

year, after migrating to a less serpent-y sec-

tor of Gorongosa’s one million acres, they

made up for lost time. Beira gave birth in

late April to 11 pups, who emerged from

their den in early June and appeared on

camera trap footage to be thriving, as well

as inexcusably cute (although the runt of

the litter eventually died).

Of greater surprise to Ms. Bouley and her

colleagues, Nhamagaia, the beta female of

the pack, defied the L. pictus convention

that only the resident alpha female gets to

breed, and in late June delivered her own

litter of eight.

The researchers initially feared that

Beira and the other adult dogs might reject

the off-label young, leaving them to die of

neglect. But no: The new pups have been

swept up into the sens-a-round frenzy of

carnivore kumbaya — life as an ardently,

obligately social mammal for whom, as the

wild dog expert Scott Creel of Montana

State University put it, “the worst thing that

can happen is to be alone.”

Gorongosa’s pup eruption didn’t end

African wild dogs were reintroduced to Gorongosa National Park only last year. There are already

at least two litters of pups. Surprisingly, both groups have been accepted into the same pack.

BRETT KUXHAUSEN/GORONGOSA MEDIA

A Puppy Paradise

Wild dogs were returned to a

Mozambique national park. The

first litters were not far behind.

CONTINUED ON PAGE D5

BASICS NATALIE ANGIER

Scans for Alzheimer’s have their downsides. Page 3.

Warning Signs

JUN CEN

4 ARTIFICIAL INTELLIGENCE

A bicycle navigates

the world with a chip

modeled after the

human brain.