The Threat of Biological Agents in Houston
The TMC Perspective

The consensus among local medical professionals is that Houston is probably better prepared to deal with terrorism of any kind than any other metropolitan area in the United States.

Medical, public health and governmental organizations in the city and county have spent the past month dedicated to ensuring that this remains the case. In particular, the medical community intends to make sure that local citizens are protected against the threat of bioterrorism.

Doing this requires coordination among institutions both in and outside of the Texas Medical Center, which is the role of the Medical Advisory Steering Committee of the Houston Medical Strike Team, said Dr. Richard Wainerdi, president and CEO of the Texas Medical Center. For the past month or more, members of the advisory committee have been putting into place educational components designed to explain the issues involved in bioterrorism to the medical community as well as the public at large, he said.

Dr. Ralph D. Feigin, is medical liaison to the strike team and chairman of the advisory team, as well as president of Baylor College of Medicine.

"The medical community has coalesced behind the local effort to ensure that our public health and health care facilities are alert to the potential and prepared to deal with it," he said.

Dr. James T. Willerson, president of The University of Texas Health Science Center at Houston, and Medical Advisory Steering Committee member, said, "There’s a lot of work ahead of us – the events of Sept. 11 changed our lives and changed the lives of many across the world."

He said the advisory team is well up to challenge posed by potential terrorists who might target any local areas.

City and county health departments and the communicable disease alert system help public officials maintain a close eye on the numbers and types of illnesses being seen in the area’s clinics and emergency departments. They are looking for the disease patterns that could be the first sign that bioterrorism is at work in the community. In addition, a tightly knit infectious disease community with representatives from both medical schools, as well as from the community, makes it easier to spot such patterns and deal with them efficiently. Each week, Houston infectious disease specialists and infection control practitioners meet to discuss unusual cases of disease and trade notes about diseases and disease patterns being seen in their respective institutions.

All of these activities predate Sept. 11, 2001. Leaders in the Texas Medical Center’s 42 institutions, along with emergency management officials from the city of Houston and Harris County and community hospitals, began preparing for a local disaster several years ago. The recent devastation wreaked by Tropical Storm Allison proved that the Texas Medical Center and community hospitals could work as a team to ensure that patients receive care in safety.

Dr. Feigin said more than 150 medical and paramedical professionals in the Houston community who have specific interests and expertise in various areas that could be pertinent to terrorism such as infectious diseases; chemical agents and radiation have become part of team subcommittees that are planning ways to improve local security.

The various sub-committees will put together a comprehensive document on biological and chemical agents that can be used in the event of a terrorist disaster, he said. A group is also working to translate this document for the lay public.

Another task is to devise an early-response rapid triage system.

"I believe that Houston will be a prototype of how cities, and the nation as a whole, might be prepared to respond to events of this type," said Dr. Feigin.

Dr. David E. Persse, director of the city of Houston emergency medical services, and a member of the committee, concurs that Houston is well positioned to handle a bioterrorist attack, particularly one involving chemicals, which are omnipresent in the city and its surrounding areas. The Houston Fire Department’s HazMat team is the largest and most active in the nation.

"The professionals at UT-Houston, Baylor and UTMB have the clinical expertise to handle biological materials," Dr. Persse said. "It has been a great single effort between traditional city services and the medical community."

Committee member Dr. S. Ward Casscells, interim vice president for biotechnology and the John Edward Tyson Distinguished Professor of Medicine at the UT Health Science Center at Houston, said, "I am convinced that Houston is more united in its effort against bioterrorism that any city in the country. Dr. Persse had us well ahead of the average city years ago. Three percent of first responders nationwide have had counsel on biological and hazardous materials training. Here it is at about 90 percent," he said.

Dr. Edward J. Septimus, medical director of infectious diseases and occupational health at Memorial Hermann Healthcare System and another committee member, said a biological attack in Houston is possible, but that "our surveillance system and rapid diagnostic abilities would allow us to respond in a rapid way to minimize any potential exposures, illnesses or casualties to the general public. The general public should feel reasonably confident that we’re going to be prepared and able to respond to any community challenges."

Dr. Herbert L. DuPont, another committee member, and chief of internal medicine at St. Luke’s Episcopal Hospital, said, "I suspect that if we have an attack, it will be limited and more symbolic than broad – designed more to frighten than disable or kill."

He said the strike team is implementing safety measures such as a broad approach to dealing with all sides of the issue.

"Everyone in the United States is concerned with the currently evolving anthrax problem," he said. "Those of us in the health care industry, such as the hospital and medical staff at St. Luke’s, are on the front line for the city of Houston. Have confidence in our medical and public health leaders."

Committee member Dr. John Mendelsohn, president of The University of Texas M.D. Anderson Cancer Center, said bioterrorism presents a critical challenge, because of the intentional release of a biological or chemical agent could unfold over several days or weeks and culminate in major epidemic.

"Early detection and being prepared are of paramount importance," he said. "It is critical that medical and health professionals work together to coordinate our efforts so that we may respond swiftly and decisively. None of us has all the expertise needed to react effectively alone. We must pool our intellectual and material resources to be effective."

Dr. James H. "Red" Duke, professor of surgery at The University of Texas Medical School at Houston and J.B. Holmes Professor of Clinical Sciences at The UT-Houston Health Science Center, and another member of the advisory committee, said the spirit of cooperation among medical facilities, medical personnel and local officials means that the city and county can feel that they are in the best of hands should a terrorist incident occur.

Above all, medical leaders advise remaining calm.

Dr. Kenneth L. Mattox, chief of staff at Harris-Ben Taub General Hospital and vice chairman in the Department of Surgery at Baylor, is another committee member who said, "Stay calm, and keep awareness high. Take a "vaccine" against fear and hysteria."

Dr. Dupont said, "Fear is the major weapon of the terrorists, and we must not let this become widespread."

Dr. Feigin said to keep the issue in perspective. For example, there are more than 30 million cases of influenza in the United States each year, and approximately 30,000 deaths.

When people ask, "What should we do?" Dr. Feigin advises, "Go get your flu vaccine. You are more likely to die in a car accident if you don’t have your seatbelt on than you are to die of anthrax."

– The University of Texas Health Science Center at Houston also contributed to this article.

Frequently Asked Questions and Answers About Bioterrorism

Q: What kind of threat does anthrax pose to my family and me?

A: The organism that causes anthrax is naturally occurring bacteria found in the soil, animals and animal products. However it was developed as a biological weapon by many countries, including the United States and the former Soviet Union in the 1960s–1970s.

The disease materializes in three ways: cutaneous (skin), pulmonary (inhaled), or gastrointestinal. Cutaneous is the most common form. It begins as a raised, itchy bump, and can quickly become and ulcer with a black center. If left untreated, lymph glands in the adjacent area will swell. If appropriately treated with antibiotics, it is rarely fatal.

Pulmonary anthrax begins with symptoms similar to those of a cold. A period of 48 to 72 hours is the window of time when a person might start to show pulmonary anthrax symptoms. Without treatment, within several days breathing problems will develop, and the body can go into shock.

Gastrointestinal anthrax is contracted by eating contaminated meat. It causes a severe inflammation of the stomach and intestines, nausea, loss of appetite and fever. Twenty-five to 60 percent of these cases are fatal, but there has never been a case of gastrointestinal anthrax in this country.

Anthrax is not spread from infected persons to others. Pulmonary anthrax is not difficult to catch because a large dose of spores of very small size must be inhaled into the lungs.

If a person does become infected with the organism, early treatment with antibiotics such as ciprofloxacin and other fluoroquinolones, tetracycline and doxycycline, as well as some forms of penicillin can be effective, depending on the strain. People who think they have been exposed are urged to contact health authorities as soon as possible. A vaccine also exists but not in quantities to protect the entire population. The vaccine is given in three doses at two-week intervals, along with appropriate antibiotics. It has been produced for the U.S. Department of Defense and is not available to civilians as this time.

Q: What is the likelihood that smallpox could become a bioterrorist weapon, and what threat does it pose to my family and me?

A: Smallpox was declared eradicated by the World Health Organization in 1980, although vaccination against the disease had already ceased in most of the industrialized world long before that. Some stores of the virus have been maintained the U.S. Centers for Disease Control and Prevention in Atlanta, and at Vector in Novosibirsk Region, Russia. It is feared that there may be some stores in the hands of terrorists.

Smallpox can be transmitted from person to person through respiratory exposure and kills as many as 30 percent of the unvaccinated population. Nobody in the United State has been vaccinated against it for nearly 30 years. However, the U.S. government has some stores of the vaccine and has contracted for the production of more. More than one-third of the $1.5 billion requested by the U.S. Department of Health and Human Services for the bioterrorism fight is designated to scale up smallpox vaccine production to the point where there is enough for everyone who could be exposed. In the meantime, the department is attempting to determine if diluted doses of the material it has on hand can provide sufficient immunity. Baylor College of Medicine is one of the test sites for that program.

The danger is that people can carry the disease for several days, spreading it to others, without showing any symptoms. Symptoms begin by a fever, followed in three days by a typical rash all over the body. While smallpox would be a potent terrorist weapon, they would find it hard to contain. It is as likely to infect the populations where the terrorists live, as it is the countries against which they mount assaults.

There are no antiviral drugs that have been found to be effective in treating smallpox, but a person who receives the vaccine within four days of exposure will probably be protected from the disease or at least the most serious side effects. After seven days, experts recommend giving the person vaccinia immune globulin.

Q: Is the plague another possible bioterrorist agent?

A: Plague spreads from the bite of an infected flea carried by rats. When it invades the lungs, it is called pneumonic plague and is easily transmitted from person to person. Bioweapons experts have experimented with ways to deliver the plague through an aerosol method that is not dependent on fleas. In this way, the organism goes directly to the lungs, causing the most severe form of the disease. The infected person becomes ill after two to four days with bronchopneumonia, fever, chills, cough and shortness of breath. Without treatment, the disease rapidly shuts down the respiratory system and the person dies. There is, at present, no vaccine that is effective against plague, although one is under development at this time. However, streptomycin or gentamicin is the preferred treatment. Doxycycline, ciprofloxacin or other fluoroquinolones could also be used. Chloramphenicol is recommended for meningitis associated with plague. Any of these drugs started as soon as symptoms appear could be lifesaving.

Q: What is tularemia?

A: Tularemia is not transmitted from person to person. However, if the organism that causes it is released in the air, it causes a systemic illness or pneumonia within three to 10 days of exposure. It begins with a flu-like illness that quickly migrates to the lungs. Untreated, it can be fatal to 35 percent of those it infects.

Although there is an experimental vaccine, it is not effective after the person has been exposed to the disease. Doxycycline or ciprofloxacin that is begun soon after exposure, before symptoms appear, and continued for 14 days, might prevent the disease all together. After symptoms, gentamicin, taken daily for 10 to 14 days, is the treatment of choice, with streptomycin, doxycycline and ciprofloxacin as alternatives.

Q: Is botulism a potential bioterrorism agent?

A: Yes. Clostridium botulinum, the anerobic bacteria involved, produces botulinum toxin, which could be distributed in aerosol form and by food contamination. The toxin first attacks the cranial nerves, followed by skeletal muscle paralysis that descends down the body within 12 to 73 hours of exposure. Respiratory failure quickly follows. If the contamination is food borne, the symptoms may include abdominal cramps, nausea, vomiting and diarrhea.

The toxin, when introduced in food or drink, can be inactivated by heating it to 85 degrees Centigrade for at least five minutes. There is no generally available vaccine to prevent infection, but antitoxins for the various forms of botulism, prepared from horse serum, are available. These are is available in single-dose, 10-milliliter vials that are diluted before being given intravenously. Some patients have allergic reactions that can be life threatening. An experimental human antitoxin has been used in infants.

Q: What about viruses such as Ebola?

A: Many viruses, such as Ebola, Marburg, Lassa and Junin, can cause hemorrhagic fevers. All of these have been considered as possible warfare agents that can be spread through the air and can be transmitted from person to person. Symptoms include conjunctivitis, fever, muscle aches, a rash of tiny red spots, and low blood pressure. In many instances, diffuse bleeding develops. The mortality rates vary from 25 percent for Lassa fever to 90 percent for Ebola.

Ribavirin given intravenously has been used to treat some cases of Lassa fever with some efficacy. Intravenous ribavirin is available from the CDC on a compassionate use basis. There is an experimental vaccine under development that shows promise in preventing Argentine hemorrhagic fever that results from Junin infection. Ribavirin also appears to be effective against the Argentine fever itself. Other that these treatments, there is only supportive therapy available for those who contract these diseases.

Q: Is chemical terrorism cause for concern?

A: Chemical terrorism can involve a number of agents that affect different organ-systems and cause different symptoms. The danger of chemical poisoning is well understood on the Texas Gulf Coast with its concentration of petrochemical refineries and other manufacturing. Frequent disaster drills in the area deal with the aftermath of chemical spills, which require decontamination and treatment of patients along with protection of hospitals from the negative effects of such chemicals.

Q: What is Sarin and why does it create so much concern?

A: Sarin interferes with the action of a chemical that is key to the control of muscles. It can be absorbed by breathing, through the mucous membranes and skin. Those who think they have been exposed should remove contaminated clothing and wash their skin with large amounts of soap and water, or 5 percent liquid household bleach, rinsing well with water. After that, they should call 9-1-1. Many communities stock an antidote to the chemical.

Q: What other agents exist?

A: Mustard gases and arsine – both blistering agents that can affect the skin and mucous membranes. Many gaseous agents can make it difficult for an individual to take in enough oxygen, causing them to suffocate. Use of these agents, however, is subject to atmospheric conditions that can render them much less potent or effective.

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©2006 Texas Medical Center

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