Tularemia

Yup, real risk for this one
How do you spell *h*e*r*b*c*i*d*e exposure?


http://www.mvgazette.com/news/2005/01/14/tularemia_vaccine.php

Blood Donors Will Kick Start Research for Tularemia Vaccine

By CHRIS BURRELL

Fueled by a federal grant aimed at countering a bioterrorist attack,
scientists at a Providence, R.I., pharmaceutical company are banking on the
collection of blood samples from nearly two dozen Vineyarders to help them
develop a new vaccine against tularemia, the rare disease with an
unexplained presence on Martha's Vineyard.

Since the summer of 2000, 30 people on the Island have been infected with
the disease. One of those cases was fatal.

The tularemia bacteria is also one of the top five bioterrorist agents
listed by the National Institutes for Health (NIH). As part of a
counter-terrorism initiative unveiled last summer by President George W.
Bush, the NIH awarded EpiVax, Inc., a small biotechnology firm in Rhode
Island, an $831,000 small business grant last fall to begin the first phase
of creating a vaccine against the virulent disease.

Next Thursday at 5:30 p.m. in the Baylies Room at the Whaling Church in
Edgartown, representatives from the company will come to the Vineyard and
hold a tularemia forum and recruit people who have had the disease to
participate in the research project that is expected to last two years.

What researchers really want is blood samples from as many as 20 such people.

"We'll take people who were exposed to tularemia in the past. Once you've
been exposed to the pathogen, you generate a memory, and the next time you
see it, the body fights it better and you don't get sick," Daniel Rivera,
the laboratory director at EpiVax and a molecular biologist, told the
Gazette yesterday in a telephone interview.

The blood sample needed is small, just eight to 10 tablespoons, said Mr.
Rivera. Participants will be paid $100. Donna Enos, an infection control
nurse at the Martha's Vineyard Hospital, has been hired by the company to
draw the blood and screen participants.

The decision to turn to the Island for help was obvious. It's just a couple
hours from Providence, a geographic advantage that gave EpiVax biologists
the idea to apply for the grant. More importantly, however, the Vineyard is
the only place in the country to experience two outbreaks of tularemia, one
in 1978 and the other beginning in 2000. There were four confirmed cases on
the Island last year.

Nearly all of the victims of the more recent outbreak have been people who
worked outdoors, typically as landscapers. But what has made the Island
even more notable in the medical history books is the fact that 21 of the
30 confirmed cases have been the pneumonic form of the disease, which is
characterized by the sudden onset of flu-like symptoms.

Epidemiologists from the Centers for Disease Control (CDC) concluded more
than three years ago that the pneumonic cases on the Island were likely
caused by inhaling airborne particles laced with the tularemia bacteria.
Landscapers were determined to be at the highest risk for contracting the
disease, prompting a public health advisory that urged them to wear dust
masks while mowing lawns and cutting brush. The disease is more commonly
transmitted through a bite from a dog tick.

No one ever suspected that the Vineyard outbreak was the result of any
terrorist attack, but the thread between bioterrorism and the pneumonic
cases on the Island has drawn significant attention from the federal
government. A terrorist attack would likely use airborne tularemia.

Three times in the last four and a half years, the CDC has dispatched
epidemic intelligence teams to the Vineyard from its infectious disease
facility in Fort Collins, Colo.

But the NIH move to push for a tularemia vaccine represents a significant
shift in the federal approach. The epidemiologists from Fort Collins were
collecting data here - rabbits, rats, ticks and soil samples - in an
attempt to unlock the mystery behind the outbreak, answering the big
question: Why is tularemia so prevalent on the Island and nowhere else?

In the wake of the Sept. 11 attacks and President Bush's anti-terrorism
policies, the focus has turned simply to preventing transmission of the
disease through a vaccine.

The grant to EpiVax is about developing counter measures to bioterrorism,
said Lanling Zou, a program officer and molecular biologist with the NIH
National Institute of Allergy and Infectious Disease in Bethesda, Md.

"Based on its potential for use as a biological weapon, tularemia is a
category A priority along with anthrax and plague," she added.

Nationwide, there are just 200 confirmed cases per year of tularemia, Ms.
Zou told the Gazette yesterday. An experimental vaccine is available, but
only for scientists working in labs where they are exposed to the bacteria.

Mr. Rivera said the blood from Islanders who have had tularemia is a key
component to developing a vaccine. Scientists at EpiVax, working in concert
with biologists at Brown University and Rhode Island Hospital, will extract
T-cells from the blood and use them to develop the building blocks for a
vaccine.

"We expose them to these little synthetic peptides, and if they've seen
tularemia before, they give a response, the cells will get turned on and
secrete a protein immune response," said Mr. Rivera.

That's phase one. If successful, phase two involves testing the vaccine on
mice at the University of Massachusetts Medical School in Worcester. Mice
would be vaccinated and then infected with tularemia. They would also be
infected first and then treated with the vaccine to see if it was
therapeutic after exposure to the bacteria, Mr. Rivera explained.

For now, phase one depends on the Vineyard participating. This is where
EpiVax is concentrating efforts.

Meanwhile, at least one scientist is still working to solve the riddle of
tularemia on the Island. Sam Telford, an associate professor of infectious
diseases at Tufts University, has continued to collect dog ticks from the
Vineyard and study them for clues.

In November, Mr. Telford published a study in the Journal of Clinical
Microbiology, detailing his field work on the Vineyard from 2001 to 2003.
Findings show that of the 4,246 dog ticks dragged from Island fields and
plucked from animals such as skunks, only seven-tenths of one per cent test
positive for tularemia.

But in the Squibnocket region of Chilmark, that rate jumps to four per
cent. What's more, skunks and raccoons trapped and released by Mr. Telford
and his teams have also tested positive. "We collected six rabbits from our
site near Squibnocket," he wrote in the journal. "Three of them were dead
or dying and yielded evidence of infection by F. tularensis (scientific
name for tularemia)."



Originally published in The Vineyard Gazette
edition of Friday, January 14, 2005



----------------------