Decon formulation likely would stop SARS virus quickly, Sandia/K-State team shows
Decontamination formulations developed at Sandia to stop the deadly effects of chemical and biological warfare agents are likely effective at killing the virus that causes Severe Acute Respiratory Syndrome (SARS), a Sandia/Kansas State University research team has shown.
Last winter, spring, and summer the SARS virus infected 8,898 people in 30 countries and caused 774 deaths. Whether a SARS outbreak materializes this year on a broad scale remains to be seen. So far only a few cases have been confirmed in Asia.
In a series of tests conducted recently at K-State on Bovine coronavirus (BCV), the internationally accepted surrogate for the SARS coronavirus, modified versions of Sandia’s DF-200 formulation, also known as "decon foam," fully inactivated BCV samples in one minute or less.
The team now is pursuing funding to conduct similar tests on the SARS coronavirus, and the team’s members hope to test the formulations against other emerging infectious diseases such as the avian influenza virus, or bird flu, which now is spreading rapidly through Asian chicken populations and has infected some humans.
Recent research suggests that the SARS virus can remain active on contaminated surfaces for days, and health officials speculate that places where infected people congregate, such as airports and hospital wards, might have served as super spreaders during the SARS outbreak.
The Sandia/K-State researchers believe that cleaning facilities with chemicals proven to inactivate the virus might significantly blunt an outbreak and possibly prevent regional epidemics from becoming worldwide epidemics.
The Sandia decontamination formulations are designed to be less harsh and easier to use than other chemicals used for decontamination of biological agents, such as bleach and ammonia. Tailored formulations have been under development at Sandia for military and homeland security uses since 1996.
In 2001 the earliest version of the commercially licensed foam were among products used in cleanup efforts at facilities contaminated with anthrax in New York and Washington, D.C.
Margin of certainty
To give the researchers enough scientific confidence that the formulation would reliably stamp out SARS regardless of the circumstances, the Sandia/K-State team tested the formulations against BCV using cell culture methods with and without organic material present. Organic materials such as soil and feces may improve the survival rate of coronaviruses and can react directly with the disinfectant to make it less effective.
They also used diluted concentrations of the formulation, down to 10 percent of normal, and altered recipes of the formulation with similar results.
"We didn’t want to test the formulations in the best-case scenario," says Cecelia Williams (6245). "We wanted the worst-case scenario to provide a margin of certainty that this would inactivate the SARS-causing virus under real-world conditions."
Two commercially available versions of the Sandia formulation also were effective in inactivating the virus in the tests, she says.
Currently no disinfectant products are registered with the Environmental Protection Agency (EPA) specifically for killing the SARS virus on surfaces.
Protocols for viral inactivation
A second significant outcome of the joint research is a set of protocols and a methodology to verify viral inactivation, says Mark Tucker (6245). A SARS workshop in October 2003 sponsored by the World Health Organization identified the standardization of test protocols as one urgent need in responding to future SARS outbreaks.
Currently very little information is available in the scientific literature regarding chemical inactivation of viruses, says team member Jill Bieker (6245), a Sandia student intern currently working on a PhD at K-State. The work at K-State is conducted under the guidance of Dr. Sanjay Kapil, a world-renowned coronavirus expert.
As part of the project, Sandia conducted experiments to develop methods of applying the formulation and to determine how inactivation can be measured and verified. The team also modified common laboratory diagnostic tools and assay techniques to test the foam’s efficacy against BCV.
The work built on previous efficacy studies on chem-bio agents Sandia had performed for DOE, the military, and the Department of Homeland Security.
"The protocols developed for this project could be rapidly modified to help provide health officials and researchers around to world with a method of verifying viral inactivation," says Jill. "It would allow officials to respond more quickly to future disease outbreaks and to quickly identify the disinfection products that work best against a particular virus."
SARS and other viruses
The researchers are optimistic that the Sandia formulations could become an effective means of minimizing the spread of returning viruses such as SARS and the Norwalk (cruise ship) virus, as well as more common viruses such as influenza.
"Flu and other viruses have similarities that give us reason to believe our formulations would be useful for general viral disinfection and decontamination if used for regular cleaning of certain facilities," says Jill.
The Sandia decontamination formulations can be deployed as a foam, fog, mist, or spray, meaning they could be sprayed on walls or dispersed as a fog throughout the air-handling system of a building, says Cecilia.
Team members include Cecelia , Jill, Mark, Caroline Souza (6245), Dr. Sanjay Kapil (K-State), and Dr. Dick Oberst (K-State).
The joint effort began in June 2003, just as the initial SARS outbreak was winding down, when Labs Executive VP Joan Woodard asked whether Sandia’s decontamination technology would be effective against the SARS virus.
The foam team’s response was, in essence: "We think it would be effective, but we won’t know until we have some data."
"We thought it would work well against SARS, but we needed to work with something similar," says Cecelia Williams.
VP-6000 Bob Eagan helped secure mid-year LDRD funding, and the project was under way. The initial work to define study parameters and modify formulations was done at Sandia. Later work with BCV was done at KSU.
"We have made significant progress in a short period of time," says Mark. "The goal was to have something to contribute this winter in case SARS came back as a seasonal virus, like the flu."
Playing a leadership role
So far this year only a few SARS cases have been confirmed in Asia, but Mark says the effort puts Sandia in a position to play a leadership role in establishing consistent worldwide protocols for disinfection efficacy for SARS should the need arise.
"Being first and having solid scientific data and a protocol gives us a real strong hand in saying this is how you do it," he says.
The work to inactivate SARS is part of a larger Sandia program to develop a toolkit of technologies useful for responding to future infectious disease outbreaks. The program includes research to model air flow and predict the transport of airborne chemical and biological agents through buildings or aircraft.