Bioterrorism is back in the news after letters containing the toxin ricin were sent to New York City Mayor Michael Bloomberg last week, a month after similar attempts were made to poison President Barack Obama and officials in Mississippi.
But even when bioterrorism isn’t being discussed on the evening news, OMRF scientist Mark Coggeshall, Ph.D., is still working to understand and fight another threat: anthrax.
The ricin letters sparked new fears about bioterrorist attacks. But science can’t just react to what’s in the news—it has to follow the course of discovery, said Coggeshall, who holds the Robert S. Kerr, Jr. Endowed Chair in Cancer Research.
“I’ve been studying anthrax since 2003, but before that I was doing research on inflammation in autoimmune diseases like lupus,” he said. “It’s a pretty ideal transition, really, because inhalation anthrax causes overwhelming inflammation.”
Though anthrax isn’t as hot a topic now as it was, his research continues, because the threat hasn’t gone away, he said.
“Ricin is a really ineffective way to cause terror. You actually have to inject it,” he said. “With anthrax, you just inhale it and you’re sick. The worst part of the sickness is you don’t know until it’s too late. As a bioterrorism agent, it’s ideal.”
In 2001, letters containing concentrated anthrax were sent to news media and the offices of then-Senators Tom Daschle and Patrick Leahy, resulting in 22 infections and five deaths. This is a form of inhalation anthrax, in which spores are cultivated, dried and prepared. It takes the inhalation of at least 2,500 spores to cause an infection.
Once inhaled, anthrax spores move from the lungs to the lymph nodes, where they begin multiplying and creating proteins that attack human cells.
The symptoms begin with fever, cough and vomiting. Shortness of breath, abdominal and chest pain and chills are common. The first stage may last only hours or it could go for days. This is the period in which antibiotics would be effective, Coggeshall said. But because the symptoms feel like influenza, patients do not seek medical attention.
The second stage of anthrax infection can last between two and four days and include difficulty breathing, heavy sweating, skin discoloration and eventually death.
“What makes anthrax deadly is massive inflammation,” Coggeshall said. “Inflammation can be good. It’s a sign the body is healing itself by fighting infection. But in the case of inhalation anthrax, the inflammation is everywhere. A whole-body infection like anthrax overwhelms the body and kills the person infected.”
That’s similar to another condition studied at OMRF—sepsis. In sepsis, a blood poisoning triggers a massive immune response, but the cure is worse than the disease.
“We think sepsis is the cause of death with inhalation anthrax,” he said. “Every pathological feature you see in a person with inhalation anthrax is exactly what you see in a person with sepsis by any other organism.”
And that might be the clue necessary to find a treatment that can save lives, Coggeshall said.
“Anthrax vaccines work, but the vaccine is not given to everyone. It’s important to find a way to save people after they’ve been exposed to anthrax, as well,” he said. “Because if we can find a way to fight anthrax, we think it will apply to other antibiotic-resistant bacterial illnesses, like MRSA.”
