Nonagenarian Israeli scientist is still innovating

Nobody else was figuring out a way to better diagnose deadly ‘superbugs,’ so Nathan Citri did it himself.

 Nonagenarian Israeli scientist is still innovating


Citri at his university office, surrounded by photos of his late wife and son, along with other diagnostic kits he’s invented. Photo by Lorena Sabater

By Avigayil Kadesh

From his easy chair in a Jerusalem assisted living residence, Prof. Nathan Citri wondered why the desperate call of the World Health Organization for a way to contain antibiotic-resistant bacteria remained unanswered, and hospitals continued to be hotbeds for these deadly “superbugs.”

The 91-year-old Hebrew University microbiologist formally retired in 1989 but never stopped searching for solutions to urgent problems in medical diagnostics. He and his late wife and collaborator were especially focused on advances to benefit the world’s neediest populations.

In his home and university labs, they’d developed a prototype for bedside kits that detect and identify resistant bacteria from blood or urine samples, yielding lifesaving information within minutes. The standard lab technique, developed more than a century ago, takes precious days.

 Nonagenarian Israeli scientist is still innovating

The “superbug” ID kit that could save thousands of lives each year
Photo by Lorena Sabater

“Up until six months ago I was still confident that somebody would come up with this — to me, obvious — idea, but nobody did,” Citri says.

Realizing it was up to him, in September 2011 he took his iPad to London to show his idea to a world expert in the field, as well as the consistent results from a prototype produced at a British lab to which he’d emailed instructions.

Duly impressed, the expert gave Citri contacts at two British companies with the technology to produce this kind of kit. Both sent representatives the very next day to Citri’s hotel. The first one to arrive got the contract, administered through Hebrew University’s tech transfer company, Yissum.

The lucky rep “was excited beyond belief,” says Citri. “There have been countless attempts at solutions, and my idea was so simple and straightforward.”

Though he’s no technophobe, he always urged his students at Hebrew and Harvard universities to see that simpler things leave less room for error.

“If I become aware of a problem that I feel like addressing, I try to simplify it to the extent that I can try my hand at it,” says Citri, who earned his PhD from Hebrew University of Jerusalem in 1954 and was academic vice dean of its medical school from 1982 to 1988.

‘This country saved my life’

Born Natan Cytrynowski in Lodz, Poland, in 1921, he was raised by ardent Zionist parents who spoke to their children in Hebrew – then a newly revived spoken language.

His fluency in Hebrew eased his absorption into pre-state Israel at 15, and earned him the chairmanship of the committee tasked with translating life-sciences lingo for the Hebrew Language Academy. Later he also coined new terms, three of which appear in a new booklet celebrating the Academy’s centennial with one outstanding example from each decade: milkshake (k’tzif chalav), microorganism (yetzoron) and blackout (chishachon).

Letters written in Hebrew are the only keepsakes he has from his parents and sister, all murdered by the Nazis.

On his own, Citri arrived in Palestine’s Ben Shemen agricultural youth village in 1937 through Youth Aliyah, a rescue organization established by Hadassah founder Henrietta Szold. Fittingly, today he lives on Szold Street not far from Hadassah University Medical Center.

“This country saved my life,” says Citri.

Lacking a high school diploma, with encouragement from the Jewish Agency he sat for exams to gain acceptance to Hebrew University, after volunteering in the British Army from 1942 to 1946. He studied bacteriology.

“When I was about 10, a book called Microbe Hunters was translated into Polish and I read it. They became the heroes of my childhood,” says Citri. “But I never planned to be a microbiologist. I intended to become a pioneer. However, after the army there was a call … for people to replace the lost Jewish intelligentsia, since so many had perished in Europe. I felt it applied to me. My parents were intellectuals and could have contributed so much. They were murdered at such an early age, and my sister wasn’t even 19.”

Taking time off to fight in the 1948 War of Independence, he earned his doctorate and did research fellowships at the National Institute for Medical Research in London and at the University of Illinois.

The love of his life

Citri married and fathered Miki, now a social worker in the Hadassah Medical Center; and Yoav, a scientist whose promising potential was cut short by a fatal accident in 1995.

He and his wife separated when the children were preteens. He met Naomi Zyk, a PhD from Montreal’s McGill University, when she was hired as his lab assistant during a stint at Harvard in 1962. For the next 50 years, until her death in 2011, she shared his life and worked by his side virtually 24/7.

In fact, the devoted couple started developing the resistant-bacteria ID kits together. “She didn’t live to see it become a reality, but she knew it would,” says Citri.

However, he says their best collaboration was their son Amichai, 38. A neurobiologist, he is finishing a post-doc at Stanford and will join the Hebrew University in August with a double appointment: at the Silverman Institute of Life Sciences and at the Safra Center for Brain Sciences. His proud father encouraged him to take the offer rather than remain in the United States.

“I can assure you that if I’d been offered positions abroad, I wouldn’t have hesitated to choose Hebrew University,” Citri relates. “I grew up without a country and my parents dreamed of settling here and had no way to get here. This is a country where, whatever you are lucky to contribute to, there is a good chance that you will live to see it make a difference. There is no other place like Israel.”