Vaccinations Against Bioterror Attacks?

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http://www.cnn.com/2001/HEALTH/10/07/bioterror.vaccines.ap/index.html

Vaccinations against bioterror attacks?

 

By Daniel Q. Haney

AP Medical Editor

 

(AP) --Bioterrorists? Germ attacks? If the threat is real, why not roll up

our sleeves and get vaccinated?

 

Vaccine experts say the question has come up often since September 11, and

though certainly a reasonable one, many doubt population-wide shots will be

a practical defense anytime soon against the deliberate release of deadly

microbes.

 

The possible health hazards of mass vaccination could easily outweigh the

benefits, they say, especially considering that no one really knows the

likelihood of such a catastrophe. But beyond that are significant problems:

No vaccines are available for civilian use except smallpox shots, which are

in extremely short supply until at least next year; and the government's

sole supplier of anthrax vaccine has failed to meet federal drug standards

and isn't currently producing the vaccine.

 

But even if immunizing the entire U.S. population against terrorist bugs is

unlikely, creating new and better vaccines is widely viewed as a key part

of defense against bioterrorism.

 

For some potential terrorist weapons, such as smallpox and Ebola virus,

there are no treatments at all. Anthrax and other bacteria can be treated

with antibiotics, but in the case of anthrax, at least, treatment must

begin rapidly. On Friday, a Florida man died of anthrax three days after

being hospitalized, despite treatment with antibiotics. So vaccines that

prevent infection entirely could be far more effective in the face of a

large outbreak.

 

Even before the attacks on New York and Washington, developing vaccines

against the A-list of bioterrorist weapons was high on the research agenda

at the National Institutes of Health and the Defense Department.

 

In the works are vaccines against virtually every potential bioterrorist

germ. Some might be given ahead of time to soldiers, hospital workers and

police, but most would probably be held for distribution after an attack to

stop further spread.

 

Scientists are seeking vaccines that could be produced rapidly and, once

given, build up protection much more quickly than the standard shots now

available.

 

Researchers who consult with government agencies speak of a new urgency

there. " We suddenly realize, my God, we've got to deal with this, " says Dr.

Myron Levine, director of the University of Maryland's Center for Vaccine

Development.

 

Health and Human Services Secretary Tommy Thompson said last week the

government hopes to have 40 million fresh doses of smallpox vaccine by next

summer, well ahead of the original deadline of 2004. Acambis, a British

firm, will speed up its 20-year, $343 million program to replenish the U.S.

supply. About 15 million doses of the old vaccine remain from the 1970s.

 

Smallpox was eradicated in 1977, and routine vaccinations ceased in 1980.

However, the Russians produced tons of smallpox for their bioweapons

program in the 1980s, and some experts fear some of it may have escaped,

perhaps to other countries that make biological weapons.

 

About half of Americans alive today were vaccinated against smallpox, but

the protection wears off. Dr. D.A. Henderson, director of the Johns Hopkins

Center for Civilian Biodefense Studies, estimates that only 10 percent to

20 percent of them still have immunity against smallpox.

 

Acambis' new vaccine will be grown in cell cultures and will be much purer

than the original version, derived from the pus of infected cows. The

Centers for Disease Control and Prevention plans to store it at guarded

warehouses around the country, to be shipped off quickly after an attack to

keep the highly contagious and untreatable virus from spreading.

 

The plan: Quarantine areas where smallpox is seen, then vaccinate everyone

who lives around them. Nine million doses of vaccine would be needed to

contain an outbreak that begins with just 100 infected people.

 

The logistics are daunting, especially if people are infected in several

cities. In 1947, it took a week to vaccinate 6 million people in New York

City in response to an outbreak of eight cases.

 

So why not inoculate everyone as soon as a vaccine is available?

 

" It has to be re-examined. I am certainly beginning to think that may be a

reasonable approach, " says Dr. Ronald Atlas of the University of

Louisville, president-elect of the American Society for Microbiology.

 

However, many specialists are dubious, including Henderson, who headed the

global smallpox eradication campaign. Two years ago, he led a committee of

government and academic specialists who rejected the idea, and that

conclusion still stands.

 

" The answer is definitely no, " says Henderson.

 

The main reason is the vaccine's safety. When smallpox was a true health

hazard, those risks were small in comparison. But the equation changes when

the threat cannot be measured. Experts contend that even a few hundred

deaths or serious complications that are vaccine-related would be

considered unacceptable.

 

About 3 in every 1 million people vaccinated would get encephalitis that

may lead to death or permanent neurological damage, experts estimate.

Another 250 would get a smallpox-like rash caused by vaccinia, the usually

harmless virus used for the vaccine. The rash could be fatal if not treated.

 

People with weakened immune systems -- cancer and transplant patients,

those taking high-dose steroids and people with AIDS -- could be especially

susceptible. Even if left unvaccinated, they might catch vaccinia from

those who are vaccinated.

 

Recently, British researchers announced they had deciphered the genetic

blueprint of plague bacteria. The discovery could offer new hints for

vaccine design. The current vaccine protects against the bubonic form of

plague but not the inhaled variety, which is feared as a terrorist weapon.

 

Plague and other bacterial hazards, such as anthrax, can be treated with

antibiotics. But medicines often must start soon after exposure, even

before symptoms start, to be effective. Since there probably would be no

warning of a germ attack and early symptoms could be mistaken for the flu,

treatment might start too late for many. Nevertheless, some people have

stocked up on prescription antibiotics, such as Cipro and doxycycline.

 

The current anthrax vaccine is reserved for the military, and experts seem

unanimous that it is too cumbersome for civilian use. It requires six shots

over 18 months, then yearly boosters. Add to that the fact that the

vaccine's only U.S. maker, Bioport Corp., has not produced a vaccine since

1998 because of failing to meet Food and Drug Administration standards, the

New York Times reported.

 

Several labs are doing government-financed research to find a better

anthrax vaccine, which would eliminate the need for speedy antibiotics. One

of them, Vaxin in Birmingham, Alabama, is working on a genetically

engineered version that could be given with a skin patch.

 

While it might be aimed initially at soldiers or health workers,

" vaccinating the entire population is not all that farfetched, " says Kent

Van Kampen, the company's president. But that vaccine is not expected to be

available for three to five years.

 

If it or another new anthrax vaccine works out, the thinking about

large-scale vaccination could change.

 

" If we had a great vaccine in enough quantity with no side effects and we

felt the threat was large and imminent, that would be a reasonable question

for public health discussion, " said Johns Hopkins' Dr. Luciana Borio. " We

do not have that. "

 

Medical Editor Daniel Q. Haney is a special correspondent for The

Associated Press.

 

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A Little Ol'Factory

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