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Ebola Follow-up

Hans Andersson hasse at panix.com
Thu Jan 25 21:01:34 EST 1996


iayork at panix.com (Ian A. York) wrote:

>To be entirely honest, I don't know what Andersson's argument is.  I went back
>and reread this thread (thanks to alta vista and dejanews) and, frankly,
>I'm not much further ahead - although I gather Andersson is a
>professional journalist, I'm quite honestly unclear on what he's trying
>to say here.

Okay, let me take it point by point and I¼ll try to be as clear as I can.

1. EBOLA - WORST-CASE SCENARIO

Kikwit å95 was the worst outbreak, so far - but, I don¼t believe that it¼s a worst-case scenario for Ebola.

A worst-case scenario for an Ebola-like virus was presented at the 1989 annual meeting of the American Society of Tropical Medicine and Hygiene. It was presented as a „medical war game¾, staged by the U.S. government official, Llewellyn Legters, chairman of  preventive medicine and biometrics at the Uniformed Services University of the Health Sciences in Bethesda, Maryland.

The background for the simulation was as follows:

* A civil war has broken out in a state in Sub-Saharan Africa. 125,000 civilians have been killed, 200,000 refugees have fled to neighboring countries and are in a state of starvation. Several hundred U.S. Peace Corps, Christian aid workers and American military personnel are working with vaccinations and food distribution in the refugee camps. A multinational peacekeeping force - including 800 U.S. soldiers - is stationed in the area...

* An Ebola-like virus breaks out, initially killing hundreds of refugees, and the CDC suspects it may be airborne transmitted Ebola.

* A team of four individuals from the CDC representing „nearly all the personnel in the entire Public Health Service with experience in hemorrhagic fevers¾ are sent to crisis zone, „leaving no expertise behind in the U.S.¾ When the CDC-team are requesting a high contamination, portable research laboratory, they are told that „there is only one in all the U.S. Public Health Service.¾  (These numbers are based in reality.)

* An Emergency Interagency Working Group (EIWG) is initiated by the U.S. Secretary of State, during the second week of the epidemic. It is composed of representatives from the CDC, NIH, Department of Defense and Department of State. Representatives from the WHO, UN¼s Disaster Relief and various other international organizations are participating in daily crisis meetings.

*** During a two-month period the virus spreads to every continent of the world. ***

CDC, USAMRIID, WHO and some 800 tropical disease experts took part in and witnessed this simulation.  Some details about the scenario are still top-secret Department of Health  & Human Services material. But, you can read about the„super-Ebola Pandemic¾ scenario in Stephen Morse¼s „Emerging Viruses¾ (p. 269-281), Laurie Garrett¼s „The Coming Plague¾ (p. 593-597) and in a New York Newsday special, Jan. 23, 1990.

Dr. Llewellyn J. Legters, Chair of the EIWG, answered the question if there were „any overall lessons learned from the experience¾:

„Well, to put it succinctly, the outbreak has confirmed, in a very dramatic way, just how ill-prepared we are to detect global epidemic disease threats in a timely fashion, and, once detected, to respond appropriately.¾

2. VIRUSES DON¼T RESPECT INTERNATIONAL BOUNDARIES

„You can be in an African village where people may be dying like flies. And twenty-four hours later you¼re in downtown Los Angeles and coming down with Ebola or Lassa fever, and you don¼t even know you have it.¾

--Joshua Lederberg,
Nobel laureate, President Emeritus and University Professor, The Rockefeller University
Discover magazine, Dec. 1990

Ebola has between 5 to 14 days of incubation, with no symptoms or very mild early symptoms that are similar to a cold or flu. That¼s plenty of time to board an international flight from Africa - maybe with a stop in Europe, and then a connecting flight to JFK Airport, New York.

„If we had a major epidemic in an urban area, which is quite possible - we wouldn¼t even have the resources available to the villagers in remote parts of Zaire, who might clear the land or burn down the huts to contain the infection. None would advocate burning down apartment buildings in New York City.¾

--Stephen Morse, Virologist and Assistant Professor at the Rockefeller University
TV-interview, A&E Investigative Reports, 1995

But, for those of you that are still sure that Ebola will stay in Zaire, in Africa or at least in the thirld world. Please, listen to what Anthony Sanches, one of CDC¼s real top Ebola researchers had to say in an interview, just a few weeks ago:

„People don¼t realize until their house is on fire that the town hasn¼t bought enough fire trucks. We¼ll be seeing more Ebola. Population is increasing in Africa; so are incursions into the virus¼s habitat. Sooner or later somebody¼s going to haul it back out of the jungle.¾

Discover magazine, January, 1996

3. LESSONS FROM RESTON

a. The Reston ¼89 outbreak demonstrated that hundreds of people on at least three continents were exposed to an airborne Ebola virus strain - that later proved to be harmless to humans - before CDC, USAMRIID or any other authority were aware of its existence.

b. The success in containing the filovirus from being disseminated into the human population had more to do with the biology of the virus than any intervention on the part of public health agencies. „In fact, several individuals were infected with the Reston Ebola virus but luckily did not develop disease and did not spread the virus to others. Thus, dodging the bullet in this case in no way should be regarded as a success in terms of the measures used to contain such outbreaks.¾   (Jonathan S. Allan, Primate Virologist,
Nature Medicine, Vol. 2., No. 1., Jan.1996)

4. FILOVIRUSES: MUTATION AND TRANMISSABILITY

Anthony Sanches, CDC molecular biologist and Ebola expert, has concluded that Ebola Zaire and Reston are genetically very close:

„I term them kissing cousins... But, I can¼t put my finger on why Reston is apparently apathogenic in human beings and doesn¼t make us sick¾. („Crisis in The Hot Zone¾, The
New Yorker, Oct. 26, 1992)

Ian York wrote:

>I do not want to see journalists advocating research on the latest flavour
>on the month.

>Let's look next at his concern about mutation.  He seems to feel that
>because Ebola has been shown to spread by aerosol then it might mutate to
>become as infectious as flu - or something like that.

You don¼t need to be a journalist  to come up with an Ebola strain, either yet to evolve or lurking undetected, as lethal as Zaire and as easily spread as Reston. It was actually Peter Jahrling, USAMRIID¼s virologist, that declared that „Ebola has the potential to go airborne and be spread like the flu¾. (CNN 5/14, 1995) And, it was Gene Johnson, another filovirus researcher from USAMRIID that said to Richard Preston that „an airborne strain of Ebola could emerge and circle around the world in about six weeks¾. („The Hot Zone¾, p. 65)

It¼s the researchers who have direct field and/or laboratory experience of filoviruses who are concerned about this possibility. They are concerned because research on filoviruses is still in its infancy and receives very little funding (Discover magazine, January 1996). Or, as some of the worlds foremost experts on Ebola write:

„The viral family known as the Filoviridae is unique among animal viruses families: we understand virtually nothing about the natural history and maintenance strategies of any member of the family, yet Marburg and Ebola viruses are highly pathogenic for man and are capable of epidemic transmission.¾

--A group of scientists from CDC and USAMRIID - „Filoviruses¾
Stephen Morse¼s „Emerging Viruses¾, 1993

Ebola researchers have seen several strains of Ebola that are highly lethal to humans, and one strain that was not - but, it was airborne instead. And, USAMRIID have in their study „Lethal experimental infection of rhesus monkeys by aerosolized Ebola virus¾ concluded that even Ebola Zaire have an airborne potential.

„I think that filoviruses in general, are the one group of viruses, that identified, that I find to be the most disturbing in terms of emerging infections. They have an alveolar aerosol transmissibility, they have a high lethality for man, they are highly mutable RNA viruses, and we understand so little about what there natural reservoir is, and what their properties are, in nature.That I think we have a very volatile mixture here, that could be the next emerging virus.¾

--C. J. Peters, Chief of CDC¼s Special Pathogenic Branch
TV-interview, A&E Investigative Reports, 1995

5. NEWLY EMERGING VIRUSES vs. VIRUSES THAT HAVE ALREADY EMERGED

I believe that „the magic bullet¾ for virus diseases is the gate-keeper - surveillance, early
detection and prevention.

I¼ve never said that we shouldn¼t care about  viral, fungal or bacterial diseases that have already emerged.

6. THE LESSON FROM AIDS

>If the only virus you know anything about is Ebola, then it's going to
>look like the biggest threat.  But if you look at some of the established
>killers like TB (and yes, Hans, I know you said "*This* discussion just
>happens to be about Ebola", but you're wrong; this discussion is about
>public health risks, of which Ebola is one), measles, and polio, then it's
>hard to argue that resources should be withdrawn from them in order to
>cover the hypothetical risk of a hypothetical mutation.  And if you do
>want to cover that hypothetical mutation scenario, than you should also
>cover the risk of rabies mutating, polio mutating, TB mutating, measles
>mutating ...

Okay, let¼s bring in another virus - let¼s talk about HIV vs. Ebola.

„Many of these problems may begin in the tropical Third World, but they are not localized to these areas. Most viruses that today are worldwide were once localized or åexotic¼...

If HIV had been discovered in nature before it emerged to spread round the world as a human disease, it would probably have seemed as „exotic¾ to us as Ebola does now (the same observation is also made by C.J.Peters.) In fact, from all available data, it may well have had much the same origin as Ebola...

AIDS was once an emerging viral disease. Like the other diseases discussed here, it too could have been stopped at the precrisis stage.¾

--Stephen Morse in „Emerging Viruses¾,1993

This is what Dr Joe McCormick, a former head of CDC¼s Special Pathogenic Branch and Ebola field virologist, concluded from the „Super-Ebola Pandemic¾ scenario, 1989:

„We can¼t wait until our own people are dying. Look at the AIDS situation. If we had spotted that disease when the first cases appeared in Africa, imagine how different the situation could be today¾.  (New York Newsday, Jan. 23, 1990)

Ian wrote:

>I do not want to see money being thrown at Ebola, because that
>money will come from somewhere else - and it will probably come from
>somewhere in the health care/research system, and people will die because
>they didn't get the measles vaccine that money was originally going to cover.

 A group of experts on filoviruses from CDC and USAMRIID answered that a couple of years ago, when they wrote:

 „Any årealistic¼ administrative review in 1989 could have established that filoviruses were of little significance for human health and that scarce research funds should not be allocated to expensive BL4 laboratories and oversease field programs to study them. I imagine similar opinions would have been proffered if a lentivirus had been isolated from a handful of immunosuppressed people in Zaire in the mid-1970¼s.¾

--C.J.Peters, E.D. Johnson, P.B. Jahrling a.o.
 „Emerging Viruses¾, edited by Stephen Morse, 1993.

So HIV was once an emerging virus which was incubating in the jungle while nobody was paying much attention.  And now we are dealing with the full-blown disaster of HIV/AIDS, as we will continue to have to do in the future.

 „By the time WHO realized there was an AIDS epidemic it already existed on four continents.¾

--D.A. Henderson, M.D., M.P.H. responsible for WHO¼s smallpox eradiction program.
Associate Director for Life Sciences Office of Science and Technology Policy, Executive Office of the President, Washington D.C

Yes, and by the time the „Medical War Game¾ scenario was over, airborne Ebola existed on all continents.

7. DRUG RESISTANCE AND MULTI-DRUG RESISTANT TB

And by the way - as far as I can see, there¼s a similar lesson to be learned from  our current problem with multi-drug resistant TB, and a growing number of other diseases.

Now, „we¼re running out of bullets for dealing with a number of these infections, said Joshua Lederberg. „Patients are dying because we no longer in many cases have antibiotics that work.¾ („The Coming Plague¾, p. 431)

Mitchell Cohen, director of the National Center for Infectious Diseases (NCID) division of fungal and bacterial infections, has predicted that „We are going back to a pre-antibiotic era¾. (US News & World Report, March 27, 1995, p. 52)

I agree with Lederberg, that the race against the microbes is still winnable. But, we are in deep water - because we¼re now facing a drug resistance problem that is already in full swing. Why? I believe that¼s it¼s because we didn¼t listen to early-warnings and take action when it was still a newly emerging problem. We didn¼t listen or act on Mark Lappe¼s book „Germs That Won¼t Die¾, 1981 - or other early-warnings.

8. ARE WE PREPARED TODAY FOR A VIRAL EPIDEMIC EMERGENCY?

This is what Joshua Lederberg said at a press conference where experts from 17 U.S. government agencies called for intensified international surveillance of disease outbreaks, and a quick-strike system that would respond rapidly to outbreaks:

„Efforts to monitor outbreaks and to detect new diseases early are now stripped and inadequate because of cuts in the federal budget for general diseases.¾ (AIDS Weekly News Report, August 7, 1995)

Dr. Michael Osterholm, Minnesota state epidemiologist, at the same press conference:

„Congress allocates millions for disease surveillance, but except for 15 percent, it is all directed towards AIDS, TB and sexually transmitted diseases. As a result, a major outbreak of some other type of disease, such as Hanta or Ebola, could go undetected until it became a major epidemic.¾

„Disease surveillance is at a really modern all-time low, except for AIDS¾, said Osterholm.
(AIDS Weekly News Report, August 7, 1995)

So, to answer the question in the headline:

„We are poorly prepared for viral emergence... and in the absence of effective action, tragedies like the AIDS epidemic will be repeated¾.

 --Stephen Morse in „Emerging Viruses¾, 1993

9. AFTERWORD

I¼m sorry that this posting became so long. But, don¼t worry guys - I won¼t have time to write these on a weekly basis!

I¼ve deliberately used many statements from different professionals in the medical field. That¼s because I don¼t consider myself a real expert - only a rather well informed messenger. It¼s also because some people in this group seem to have a problem with the fact that I¼m a journalist.

Best regards,

Hans Andersson, NYC
hasse at panix.com




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