Healthline asks the experts about today’s biggest bioterror threats.

Bioterrorism is back in the news with word of a dangerous new strain of botulism, for which there is no antidote. The strain is so powerful, the researchers who discovered it won’t release its genetic code until an antidote is found because they fear it will fall into the wrong hands.

U.S. agencies like the Centers for Disease Control keep lists of potential bioterrorism agents that have the highest risks of mortality and morbidity, and botulism is one of them.

However, according to national bioterrorism experts, these government lists may be based more on the deadliness of pathogens than on the true risks they pose. The feasibility of a potential delivery system should also be considered.

Margaret Kosal, an assistant professor of international affairs at Georgia Tech who has worked with the U.S. Department of Defense on these issues, told Healthline, “Most of those discussions are grounded or based in assessment of technical or physiological characteristics of the pathogen … rather than technical requirements to make an effective weapon and broader consideration of motivation. All that gets very complicated, which doesn’t mean it shouldn’t be pursued.”

She said she appreciates that the lists exist, but added that they should be reviewed periodically.

“These lists are not based on quantitative data that would assess threat levels in particular,” Richard Ebright of Rutgers University told Healthline. “These are lists that were put together hastily or put together at a time when anthrax was at the forefront of people’s minds. These are fossils of 9/11 that have not been re-reviewed or re-evaluated.”

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The new, highly potent strain of botulism, called botulism H, is a serious threat, as is any other agent for which there is no treatment. Botulism is on the CDC list, but Ebright believes there needs to be an entire category dedicated to deadly, untreatable biological agents. These include lethal coronaviruses, such as Middle East Respiratory Syndrome, or MERS, and H5N1, a strain of avian flu.

Neither of these illnesses has yet been detected in the U.S. Avian flu is not contagious among humans, but because of its ability to infect poultry, Ebright believes it could be introduced into the food system. “These viruses easily could fall into the wrong hands, even in their present form,” he said.

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Antibiotic-resistant agents should also be on the watch list, Ebright said, pointing to the CDC’s warning in September that antibiotic resistance is growing in the U.S. Every year, more than two million Americans are infected with some form of antibiotic-resistant bacteria, resulting in 23,000 deaths annually.

A couple of days after the CDC announcement, researchers funded in part by the Defense Advance Research Project Agency (DARPA), an arm of the U.S. Department of Defense, announced they had found a way to make a rapid blood test that can distinguish between viral and bacterial infections, even among unknown strains. The goal is to help curb the inappropriate use of antibiotics, which leads to resistance.

With its Rapid Threat Assessment program, DARPA is encouraging researchers to develop technologies that can map a biological threat’s molecular mechanism in 30 days or less. The idea is to speed up the development of antidotes so that potential terrorists might think twice before an attack.

Anthrax, and any other substances hardy enough to survive shipping, should also be monitored. “Nobody really anticipated that the U.S. Mail would be as effective of a delivery system as it was,” Leonard Cole, author of The Anthrax Letters, told Heathline.

In addition to the post-9/11 anthrax attacks, he noted that anthrax has been a biological weapon of choice for many years. The British experimented with it during World War II on an island off the coast of Scotland. Cole said it wiped out the livestock used in the experiment in about 24 hours, and that the island remained contaminated and off-limits until the 1990s.

The CDC, via its Cities Readiness Initiative, has already developed a plan for mobilizing America’s biggest cities in the event of an anthrax attack. The U.S. has a stockpile of medications for its citizens in the event of various bioterrorism attacks.

Salmonella and other foodborne illnesses may not be deadly, but an attack could sicken many people. “[These are] things we recover from, but they are more easily accessible and historically have been used, either for some sort of revenge or lower-level kind of attack,” Kathleen Vogel, a bioterrorism expert at Cornell, told Healthline. In 1984, a cult sickened more than 750 people in a food-borne bioterrorrism attack in Oregon.

“It’s very difficult to work with any of these agents and have them survive dissemination,” Vogel said of bioterrorism threats. “They’re living organisms.” She said simple environmental conditions such as sunlight and rain could degrade them. “You’d have to know what you’re doing if you’re working with these materials and know how to keep them stable and viable.”

In the 20th century, 300 million people died from smallpox, Cole said. The good news is that the U.S. government is extremely well prepared for a smallpox attack, with vaccinations on hand for every American.

And because it can be widely released in aerosol form, the CDC considers the bacterium Y. pestis, which causes pneumonic plague, a major bioterrorism threat. If patients are not treated with 48 hours, the fatality rate is close to 100 percent, Kosal said. The plague exists in nature and could easily be grown in a laboratory.

“The bug (aka the pathogen) itself is not a weapon,” Kosal added. “That frequently gets lost in political, policy, and popular discussions. Transforming a pathogen into a weapon can be a very different skill set.”