Written by By Lauren O’Neil, CNN
One of the biggest questions in medicine is whether a vaccination for a particular disease has an effect beyond the confines of the inoculation site. Could the injection possibly spur an alteration in clotting dynamics elsewhere in the body?
According to new research published in the Journal of Infectious Diseases , it can — if a certain drug is involved.
Dr. Frank Nichols, an immunologist and neurologist at the University of Pennsylvania, is the author of a paper published Monday in the journal that looked at the effects of a drug (antineoplaston) that can block certain proteins on the surface of key cells — proteins that produce blood clots.
Nichols has spent decades studying how infection, such as the skin-to-skin zika infection, could create potentially fatal blood clots in the blood vessels of humans and animals.
Away from the hospital, the combination of zika and corticosteroids has led to an increased risk of serious blood clots.
Dr. Frank Nichols. Credit: Emily Rhodes
“If you have to go to a hospital to be treated for a zika infection, you may want to be careful with blood vessels,” Nichols told CNN.
In humans, multiple prescriptions for an immunosuppressant drug can affect clotting — particularly if the antibody-producing antigens against the infection are present, said Nichols. He believes the chance of an antigens-based clotting response is higher than that associated with injection.
“I think what we found is a causal relationship … to the increase in blood clots after the use of anemia components to treat zika infections,” said Nichols.
Nichols is the senior author of a paper released in October that also claimed an antigens-based clotting response was higher in rodents.
“No, I don’t think that this is the FDA-approved claim, or the pharmaceutical company claim,” said Nichols, “but at the end of the day, it seems to be the case.”
This study focused on patients who have had their AIDS treatment shortened because of the Zika virus. The drug (antineoplaston) wasn’t part of their routine drug regimens prior to the infection, but following an immune globulin transplant, many patients’ regimens were augmented with the drug.
Blood flow and skin
Dr. David Karas, Director of the blood clotting disorder program at Harvard Medical School, says that it is possible that human transmission of zika through the air could lead to a form of blood clotting called “fanasia.” Fanasia is the name given to the blood swelling that forms around the venous wall, where the blood vessel is located in the head.
“A serious systemic blood clotting response probably does not exist,” said Karas. But the condition does appear to occur in some low-lying capillaries.
When it comes to looking at whether an antigens-based response could increase the risk of clots elsewhere in the body, Nichols says that with ongoing investigations, we are not at a place in medical medicine where we can give a diagnosis in such a way that we can determine if a person had a blood clot that was or was not exacerbated by an immune globulin shipment. “We’re more moving into the realm of clots being defined by an individual predisposition to clots,” he said.
One study in particular is examining whether an immunosuppressant used to help control HIV, ritonavir, actually triggers the development of a form of clots that attaches to blood vessels in the head and is called “phagocytosis.”