KUWAIT CITY, KUWAIT - DECEMBER 13: Czech soldiers in chemical protection suits take part in a chemical attack response drill conducted at the U.S. Embassy by civil defense authorities and troops from the United States, Germany, and Czech Republic December 13, 2002 in Kuwait City, Kuwait. The exercise, dubbed 'Event Horizon,' was staged to test the coordinated emergency response to a mock attack on the U.S. Embassy in Kuwait by terrorists using deadly sarin nerve gas.
Scott Nelson/Getty Images
KUWAIT CITY, KUWAIT - DECEMBER 13: Czech soldiers in chemical protection suits take part in a chemical attack response drill conducted at the U.S. Embassy by civil defense authorities and troops from the United States, Germany, and Czech Republic December 13, 2002 in Kuwait City, Kuwait. The exercise, dubbed 'Event Horizon,' was staged to test the coordinated emergency response to a mock attack on the U.S. Embassy in Kuwait by terrorists using deadly sarin nerve gas.
Now playing
01:34
What are nerve agents like Novichok and how do they kill?
Now playing
02:27
Exclusive: Inside Syria's demilitarized zone
Vaciha Turki Al Omar, 30, has been in Idlib for seven months. She on the hill overlooking the sprawling refugee camp with her kids. "We can try to fight but the kids are our weakness so we must run away," she says.
Gul Tuysuz
Vaciha Turki Al Omar, 30, has been in Idlib for seven months. She on the hill overlooking the sprawling refugee camp with her kids. "We can try to fight but the kids are our weakness so we must run away," she says.
Now playing
03:54
Major rebel stronghold in Syria under threat
Lead Martin Savidge on Florence live Jake Tapper_00022318.jpg
Lead Martin Savidge on Florence live Jake Tapper_00022318.jpg
Now playing
04:15
Cat 3 Florence coming in like a 'Mike Tyson punch'
idlib syria frontlines pleitgen 2
OTTO, CLAUDIA/CNN
idlib syria frontlines pleitgen 2
Now playing
01:49
CNN travels to the front lines of Idlib
rebuild syria
CNNI
rebuild syria
Now playing
02:15
Syrians rebuild war-torn historic city of Homs
White Helmets
Now playing
02:10
White Helmets evacuated into Jordan by Israel
Reuters
Now playing
00:56
Girl's new prosthetic legs replace tin cans
syria golan heights fleeing lee pkg_00002705.jpg
CNN
syria golan heights fleeing lee pkg_00002705.jpg
Now playing
02:15
Thousands flee toward closed borders
A day in the life of an artist-turned-barber Syrian refugee living in the Zaatari Refugee Camp in Jordan.
CNN
A day in the life of an artist-turned-barber Syrian refugee living in the Zaatari Refugee Camp in Jordan.
Now playing
04:03
A day in the life of a Syrian refugee
CNN
Now playing
02:20
CNN goes inside refugee camp after airstrikes
airstrike syria
CNN
airstrike syria
Now playing
01:29
Video reportedly shows airstrike in Syria
US President Donald Trump addresses the nation on the situation in Syria April 13, 2018 at the White House in Washington, DC. Trump said strikes on Syria are under way.  / AFP PHOTO / Mandel NGAN        (Photo credit should read MANDEL NGAN/AFP/Getty Images)
MANDEL NGAN/AFP/Getty Images
US President Donald Trump addresses the nation on the situation in Syria April 13, 2018 at the White House in Washington, DC. Trump said strikes on Syria are under way. / AFP PHOTO / Mandel NGAN (Photo credit should read MANDEL NGAN/AFP/Getty Images)
Now playing
01:02
Trump's message to Iran and Russia
Vucci/AP/SANA/Nikolsky/Getty Images
Now playing
01:42
Could the Syrian war lead to a US-Russia conflict?
This image released early Sunday, April 8, 2018 by the Syrian Civil Defense White Helmets, shows a child receiving oxygen through respirators following an alleged poison gas attack in the rebel-held town of Douma, near Damascus, Syria. Syrian rescuers and medics said the attack on Douma killed at least 40 people. The Syrian government denied the allegations, which could not be independently verified. The alleged attack in Douma occurred Saturday night amid a resumed offensive by Syrian government forces after the collapse of a truce. (Syrian Civil Defense White Helmets via AP)
Syrian Civil Defense White Helmets/AP
This image released early Sunday, April 8, 2018 by the Syrian Civil Defense White Helmets, shows a child receiving oxygen through respirators following an alleged poison gas attack in the rebel-held town of Douma, near Damascus, Syria. Syrian rescuers and medics said the attack on Douma killed at least 40 people. The Syrian government denied the allegations, which could not be independently verified. The alleged attack in Douma occurred Saturday night amid a resumed offensive by Syrian government forces after the collapse of a truce. (Syrian Civil Defense White Helmets via AP)
Now playing
01:59
Syrian attacks escalate tensions among global powers
Now playing
00:47
Families bused out of chemical attack city

Story highlights

Novichok is a "weaponized organophosphate," a category of pesticides

Symptoms include blurred vision, sweating, nausea, respiratory arrest, loss of memory and consciousness

(CNN) —  

What should a medical professional do when faced with a patient poisoned by a nerve agent?

That question became relevant to doctors in Amesbury, England, on Saturday when a couple came into contact with a Soviet-era nerve agent. And it was relevant earlier this year when the same agent – Novichok – nearly killed a former Russian double agent and his daughter.

The latest victims, Charlie Rowley, 45, and Dawn Sturgess, 44, occupy critical care hospital beds at Salisbury District Hospital, where Sergei Skripal and his daughter Yulia were treated in March, according to a statement issued Thursday by UK Home Secretary Sajid Javid.

“Our strong working assumption is that the couple came into contact with the nerve agent in a different location to the sites which have been part of the original clean-up operation,” Javid said. He also said all areas decontaminated after the Skripal poisoning are safe and pose “no significant risk” to the public.

Dr. Peter R. Chai of the Division of Medical Toxicology in the Department of Emergency Medicine at Brigham and Women’s Hospital in Boston, described Novichok as a “weaponized organophosphate,” a category of pesticides commonly used in agriculture.

The weaponized nerve agents commonly called Novichok, VX and sarin “mostly possess the same chemical structure backbone of other organophosphate pesticides,” Chai said. “But they’ve been modified to make them potent.”

In a word, deadly.

The cure itself is also far from pleasant.

Yulia Skripal, who spent 20 days in a coma after being poisoned by Novichok, described the treatment as “invasive, painful and depressing. Our recovery has been slow and extremely painful.”

Chai’s research paper on these chemical compounds – “novichok” means “newcomer” in Russian – and potential therapies was published last week.

’A sense of fear’

Andrei Zheleznyakov, a Russian military researcher, is the first person known to be exposed to one of the Novichok nerve agents. In 1987, while working on a secret Soviet chemical weapons initiative, he was exposed to the chemical compound when his fume hood malfunctioned.

“Circles appeared before my eyes: red and orange. A ringing in my ears. I caught my breath. And a sense of fear: like something was about to happen. I sat down on a chair and told the guys, ‘It’s got me,’ ” Zheleznyakov said, as quoted by Chai.

Zheleznyakov survived the exposure but developed difficulties concentrating and became withdrawn, according to his colleague Vil Mirzayanov, who described the incident and the Soviet chemical weapons program in his memoir, “State Secrets: An Insider’s Chronicle of the Russian Chemical Weapons Program.”

Though more is known today about these nerve agents, most doctors have little direct experience with them. Generally, nerve agents are colorless and odorless, though they may smell fruity, chocolatey or even like moth balls if impure.

When treating a patient who has been exposed to Novichok, there are three major steps, Chai said.

“Number one, you’ve got to recognize this has happened to somebody. You cannot treat it if you don’t think about it,” he said. Recognition is the “cornerstone,” he said, because “the most common symptoms people first develop are blurred vision, sweatiness and nausea. And, if you think about it, those are actually pretty nonspecific.”

Other signs of exposure include pinpoint-size pupils, constricted airways and respiratory arrest, memory and concentration loss, and loss of consciousness, according to the medical handbook “Responding to Terrorism.”

Symptom management

“Number two is immediate symptom management. So we treat these people with atropine, high doses of atropine,” Chai said. Atropine is a medicine derived from the belladonna plant, also known as deadly nightshade.

Chai explained that people poisoned with Novichok and other nerve agents essentially die due to secretions – vomiting, diarrhea and urinary incontinence occur all at once – and atropine counteracts these effects.

“If you look at the people who were poisoned by sarin gas in Syria, for example, if you look at those videos, everybody’s foaming at the mouth,” he said. “So we immediately give atropine to prevent that from happening.”

Atropine works in two ways, he said. Along with drying out secretions, it increases the heart rate, which slows after exposure to a nerve agent. “That essentially buys you some time to give an antidote,” Chai said.

Antidote

Giving the antidote, a nitrogen-containing chemical compound known as an oxime, is step three.

Novichok and other nerve agents bind to a receptor site in the brain where they disrupt cholinesterase, a type of enzyme needed for proper functioning of the nervous system, Chai explained.

The antidote “gets around” the organophosphate nerve agent and “essentially cleans the binding site so that you basically liberate the sealed cholinesterase and allow it to work again.”

Novichok is so deadly in part because it is “essentially engineered to prevent the antidote from working,” Chai said.

With any nerve agent, though, how fast a patient develops symptoms depends in part on the exposure method – whether they inhaled an aerosolized nerve agent, say, or consumed it as a liquid.

Nerve agents can also be absorbed through the skin and mucous membranes, according to “Responding to Terrorism.” One example of this is Kim Jong Nam, half-brother of North Korean leader Kim Jong Un, who was killed in 2017 when his face was smeared with the VX nerve agent.

Kim had immediate symptoms, Chai said.

Decontamination

Patients also will need to be decontaminated to prevent additional exposure, the medical handbook notes: “Clothing should be removed and the skin washed with soap and water. Contact lenses should be removed and the eyes thoroughly irrigated for at least 5 -10 minutes.”

Many details in the case of the British couple have not been uncovered, but the known facts suggest that the nerve agent they came into contact with is long-lasting.

“These agents can persist in the environment for days or months,” Chai said. “That’s a really long time.”

Muscle twitching and excess secretions distinguish nerve agents from chemical asphyxiant agents, such as cyanide, according to the handbook.

As for long-term effects, Chai said it’s hard to say.

“In a certain subset of people who get poisoned by organophosphates … you can develop a long-term neuropathy and weakness and cognitive issue from poisoning that last for a really long time and can be lifelong,” he said.

He cautioned that this is only speculation, adding, “Zheleznyakov developed a kind of debilitating neuropathy, so he had numbness in his arms and legs, and he eventually died of that.”

Not a DIY project

Novichok may sound as bleak as a Siberian winter, but there is some hopeful news.

Andrea Sella, a professor of inorganic chemistry at University College London, said in a statement that “nerve agents are not materials that can be made at home.”

As they’re too toxic to be manufactured anywhere but a specialized facility, the “key forensic issue here is to identify impurities and residues that might provide clues as to the precise chemical process used to manufacture the material,” Sella added.

Join the conversation

  • See the latest news and share your comments with CNN Health on Facebook and Twitter.

“There is no question that the authorities will be looking for the container used to deliver the material as the chemical contents would be a gold mine,” he said. “With this information it might well be possible to trace the origin of the substance, just as has been done for the [sarin] attack in Syria.”