Dr. D.A. Henderson also talks to GEN about how prepared we are, or not, for a bioterror attack.

Donald A. Henderson, M.D., is a Johns Hopkins University Distinguished Service Professor and Dean Emeritus of the university’s Bloomberg School of Public Health. He is also Professor of Medicine and Public Health at the University of Pittsburgh School of Medicine. Dr. Henderson, who led the effort in 1967 that eventually eradicated smallpox in the late 1970s, serves as co-editor-in-chief of Biosecurity and Bioterrorism, a peer-reviewed journal published by Mary Ann Liebert. GEN’s editor-in-chief John Sterling interviewed Dr. Henderson to find out more about Ebola and other infectious diseases, including how prepared we are for a bioterror incident.

GEN: Let’s begin by talking about the Ebola crisis in West Africa. According to Margaret Chan, M.D., Director-General of the World Health Organization, the Ebola outbreak is nearly out of control. Then there is the case of the man ill with Ebola who boarded a plane in Liberia, disembarked in Nigeria, and died five days later. How should health officials address this very serious problem?

Dr. Henderson: Several measures are needed. The likelihood that we’re going to have people on a plane with Ebola virus disease and that they’re going to transmit it quickly is small. But if one has a patient on a plane who seems ill, it’s customary for a call to be sent ahead to have a physician meet the plane, determine if there is an illness, and then take whatever action is necessary. That’s a practice now in place and pretty well established.

Ebola patients do not transmit the disease until they really get sick. At that point one has to identify those who may have been in contact with that patient and begin to think in terms of isolating them.

Once a person is diagnosed with Ebola we know from experience in previous outbreaks that one isolates the patient in a hospital and provides needed fluids and nutrients. One makes sure that the people taking care of him or her follow the proper procedures for personal protection. Then the virus will burn out quickly. It does not spread easily and does so only as a result of direct contact with the patient or with blood or perhaps vomitus.

The situation in West Africa is an extremely unique one. There are a lot of people, especially in rural areas, who are suspicious of strangers and other outsiders, including healthcare workers. Also some of the burial rituals that are common in West Africa are geared, unintentionally, to spread the virus. And patients are terrified of going into hospitals where patients are isolated because they know that’s where people go to die.

Instead, relatives and friends often care for infected people at home. That means friends and relatives are in close contact with the patients. This behavior is considered a mark of respect and care for the patient and it’s understandable. But this has served to spread Ebola in a way that wouldn’t happen in a country like the U.S.

GEN: There’s another topic in the news that I would like to ask you about. How surprised were you when six vials of live smallpox virus from, most likely, the 1950s turned up in an FDA lab at the NIH?

Dr. Henderson: I was very surprised indeed. In 1985, when we became engaged in persuading laboratories to destroy all smallpox virus specimens (they had to transfer them to one of two laboratories in Russia or Atlanta), we wondered how many might have virus samples and how many might comply. There were some 75 labs that originally reported being in possession of smallpox virus and most complied readily. We went from about 75 laboratories down to about eight in 1977 when the last cases occurred. By 1983, all had surrendered their samples except for two World Health Organization Collaborating Laboratories, one in Russia and the other in the United States.

The six vials that turned up in NIH were small and contained powdered material. I have not seen them but I’m informed that two contained viable freeze-dried smallpox virus that had been sealed under vacuum. These were probably being used as reference specimens for research that was taking place decades ago to assess various smallpox vaccine products. 

GEN: There’s a debate going on right now about what to do regarding the remaining two official smallpox stockpiles in the U.S. and Russia. Keep them or destroy them? Where do you stand on the issue?

Dr. Henderson: I'm very much in favor of destroying them. This question actually came up in the early 1980s. Many countries, particularly those that had suffered with smallpox, wanted to see the virus destroyed and the risk of its recurrence minimized. There was a general understanding that we needed to preserve the genetic information intrinsic to the virus. But we did not need the intact smallpox virus to accomplish this.

This could be done by slicing the virus up and putting the fragments into E. coli for a permanent library. A number of strains of the virus underwent this procedure. Sequencing the virus would provide even more information about its genetic nature. Fortunately, the technology was just becoming available and smallpox viruses were among the first specimens to be sequenced back then.

The vast majority of countries argued strongly for virus destruction and requested that the World Health Assembly vote on this. We were surprised, however, to find there were two countries that were much opposed to destroying the virus—the United States and Russia. Their stated rationale was based on a general principle: We shouldn’t destroy a virus. They succeeded in having the vote deferred year after year. Other countries wanted specific reasons for the continual delay on a vote.

In 2002 representatives from the U.S. cited such reasons for their views. They expressed the need, as they saw it, to have an effective smallpox vaccine that had no adverse side effects. But every vaccine, in fact, has some side effects so, in essence, an impossible objective was being proposed.

This was in 2002 and a final decision on whether to keep or destroy the virus was postponed in 2007 and 2011 and, again, this past May.

GEN: What do you say to those who argue that it will eventually be possible, using the modern tools of molecular biology, to create a synthetic form of the smallpox virus?

Dr. Henderson: To create a synthetic smallpox virus with the same properties as the original virus would be extremely difficult. Smallpox is an extraordinarily large virus and there are going to be real problems in trying to create a virus that’s exactly the same. In theory, I guess someone could.

However, if someone were able to create a synthetic virus, the question is would the present vaccine be effective against it? The answer is probably not.

GEN: A few years ago you were quoted in an article as saying the U.S. was unprepared for a bioterror attack. Do you still feel that way?

Dr. Henderson: Yes. We still have a way to go before we would really be reasonably well-prepared to deal with recognized biological threat agents such as smallpox, plague, and anthrax.

After 9/11 and the subsequent anthrax attacks, the U.S. government provided an emergency appropriation of $3 billion for the development of programs for preparedness and emergency response. State and local resources, especially the health departments, are critical to this effort. With a major bioterror attack and many casualties, it would be essential to render emergency care, to trace where the attack originated, and to implement requisite control measures. Much would depend on the existing but weak public health infrastructure throughout the U.S.

I was part of the preparedness effort, and we allocated $1 billion specifically for initiatives that would involve state and local health departments. This would require bringing together coordinate activities among public health officials, physicians, hospitals, police, voluntary agencies such as the Red Cross, and industrial personnel, as well as various other participants with the singular goal of planning what to do in the event of a bioterror attack.

Development of supporting resources is essential. In 2001, for example, we only had two laboratories in the country that could diagnose smallpox or anthrax. Now there are over 100 labs nationwide that can detect these and a range of other agents. Emergency communication networks were established and a central command post as well.

So when you ask the question how well prepared we are, I perceive that much has been done but a lot more is required. For example, say we had a release of smallpox. State and local health authorities face a number of critical questions: Are their personnel trained properly to handle this? Do they have people who know how to vaccinate? Have they drilled enough to prepare for such an event? Where are you going to put patients if they have smallpox? Do you have sections of a hospital that could be set aside for isolation?

Until the attack of September 2001, little if any thought had been given to these questions. So yes, a great number of positive actions have been taken. But as time has passed, I would say complacency has set in.

A substantial effort was made beginning after 9/11 to begin to address emergency preparedness needs. The effort probably reached a peak about four or five years after 2001. But it’s begun to ebb since then.

Definitive, rehearsed plans, stable financial resources, and experienced professional staff continue to be the vital needs. What we have now is far less than adequate. Few states or communities have adequate resources and this is not well understood.

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