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Biao He, Professor, Department of Infectious Diseases,
Infectious Diseases, Department of Faculty of Infectious
Diseases, UGA
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Mumps may seem like a disease of a bygone era to many people in the U.S.
who, thanks to immunization programs, have been spared the fever, aches and
characteristic swollen jawline of the once common viral infection. Biao He,
a University of Georgia professor of infectious diseases and a Georgia
Research Alliance distinguished investigator in the College of Veterinary
Medicine, worries that a new strain of the virus is spreading, and it could
lead to the widespread reintroduction of mumps. Now, thanks in part a $1.8
million grant from the National Institutes of Health, He and his team are
working on a new vaccine to stop it.
Although not typically a life-threatening disease, mumps can lead to serious
health problems such as viral meningitis, hearing loss and pancreatitis; and
it can cause miscarriage during early pregnancy.
Vaccinations diminished the number of cases dramatically, and at one point
it appeared that the U.S. was on pace to eradicate the disease. But two
large outbreaks of the virus in 2006 and 2010 involving thousands of
confirmed cases in the Midwest and Northeast put the hope of eradication on
hold. He is concerned that the current vaccine, which has been in use since
1967, may be showing signs of weakness.
"The virus is always evolving and mutating, and new viruses will emerge," He
said. "It's only a matter of time until the old vaccine we have doesn't
work."
The current vaccine is commonly called the Jeryl Lynn strain and is named
after the daughter of inventor Maurice Hilleman. It is based on a specific
genotype of the mumps virus called genotype A. However, the 2006 and 2010
mumps outbreaks were caused by another strain, genotype G.
Even more troubling is that most of the people who contracted mumps during
the 2006 and 2010 outbreaks had received the recommended two-dose
vaccination in their early childhood, meaning that the virus was spreading
even among the vaccinated population.
"The question is: With this new genotype virus emerging in the vaccinated
population, what do you do about it?" He said.
Some have suggested administering a third Jeryl Lynn vaccine to boost
immunity later in life, but it is unclear if that approach would be
successful. He suggests that modern scientific techniques have made the
creation of some vaccines much easier, so producing a new mumps vaccine may
be the most effective method of controlling the emerging threat.
"In the past few years, we have taken advantage of genetic engineering, and
my lab is particularly good at engineering viruses," He said. "We can take a
virus, look at its genetic sequence, take bits and pieces away and generate
a new virus with less virulence that will work as a vaccine."
Before the advent of genetic engineering, the process of creating a vaccine
could be intensely laborious, as researchers would have to pass the virus
through many generations of reproduction until they found a naturally
occurring weakened virus. This process can take long periods of time, and
there is little guarantee that the weakened virus will work as a vaccine.
Genetic engineering allows He's lab to produce an effective and safe vaccine
much more quickly.
Vaccine safety became a topic of much discussion after British medical
researcher Andrew Wakefield suggested that there was a link between the
measles, mumps and rubella vaccine and autism. However, his claims were
found to be fraudulent, and Wakefield was barred from practicing medicine in
the United Kingdom.
Much of the fallout from the Wakefield case remains, and some are still
hesitant to have their children vaccinated, but He is insistent that
administering vaccines to children is the safe and responsible thing to do.
"The No. 1 issue for us in making a pediatric vaccine is safety," He said.
"So far our testing suggests we are on the right track."
Once He and his laboratory have devised a safe, reliable method to create
vaccines for genotype G, they can apply that knowledge to rapidly produce
vaccines for the other 12 mumps genotypes currently circulating in
populations throughout the world.
Health professionals were able to contain the outbreaks of 2006 and 2010,
but He thinks that the large global population and ease with which people
move from one location to another make humankind vulnerable to rapid disease
spread.
"It's almost like a small fire; if it stays small, we can put it out," He
said. "But if conditions are right, and the wind begins to blow, the fire
can take over."
-Reprinted with permission of the University of Georgia