Dr. Mike Womack's Mosquito Research Helps
Fight West Nile Virus, Other Diseases
By Renee Pearman
Mike Womack was the kid who spent afternoons chasing butterflies and
lightning bugs and catching beetles and grasshoppers in the woods
and fields surrounding his Hattiesburg, Miss., home. By the time he
began his graduate studies at the University of Mississippi's School
of Medicine, his childhood fascination with insects had evolved into
an interest in health and disease.
Womack uses a hand aspirator to collect
Today, faculty at the Universiti Sains Malaysia, halfway around
the world from Georgia, are familiar with the research of Dr. Michael
Womack, professor of biology at Macon State College. His work also
is well known among faculty at the University of Notre Dame's Disease
Vector Biology Lab and the Centers for Disease Control's Dengue
Fever Research Labs in Puerto Rico.
Womack has made a name for himself, as well as for Macon State
College, through his extensive study of the disease-carrying Asian
tiger mosquito and, more recently, the West Nile virus.
His lectures on "The Ecology of Emerging Diseases," "The
Biology of the Asian Tiger Mosquito" and "Mosquito-borne
Viruses in Georgia" have taken him from Central Georgia civic
club meetings to hospitals, colleges and research labs across the
country. And his pursuit of the Asian tiger mosquito has led him
to the tropical Cayman Islands, the banks of North Carolina lakes
and the backyards of houses in rural Georgia.
"This is a good time to be an entomologist," said Womack,
who actually prefers the title disease vector ecologist, which,
he explained, "is someone interested in any sort of arthropod
that transmits diseases. It's really a whole new sub-discipline
Tracking a 'Tiger'
By day, Womack teaches introductory biology, microbiology for
health sciences and pathophysiology at Macon State College, but
in the evenings and on weekends, he continues his mosquito research,
which over the years has been funded by grants from the Federal
Emergency Management Agency, the U.S. Department of Defense, the
Tennessee Valley Authority and the University System of Georgia.
In the spring of 1991, Womack attended a lecture on the Asian tiger
mosquito at the USAF School of Aerospace Medicine at Brooks Air
Force Base in San Antonio. It renewed his interest in epidemiology,
a branch of medical science dealing with the incidence, distribution
and control of disease in a population. Since then, he has been
tracking the Asian tiger mosquito, or Aedes albopictus, which is
believed to have made its way into the U.S. in a cargo of tires
imported from Japan to Houston, Texas, in 1985.
During a research fellowship to the USAF School of Aerospace Medicine
in 1992, Womack surveyed communities in southern Texas to see how
far the Asian tiger mosquito had traveled. He visited tire retailers,
auto and truck repair shops, cemeteries, parks, plant nurseries
-- any "resting sites" for tires -- and
collected mosquitos using a hand aspirator. He concluded that the
insect was "widely distributed" in that part of the state,
35 counties to be exact.
The following year his article "Distribution, Abundance and
Bionomics of Aedes Albopictus in Southern Texas" was published
in the Journal of American Mosquito Control Association," an
international publication for mosquito research. Since then, lecture
requests have been pouring in. "I found myself on a first-name
basis with the mosquito guru, Dr. George Craig Jr. of the University
of Notre Dame," said Womack, who several years ago was one
of four nominees for the Georgia Public Health Association's Sellers-McCroan
Award, which recognizes outstanding achievement and service in epidemiology
and/or laboratory services.
Womack also has conducted a statewide mosquito survey in Georgia
- and he has discovered Asian tiger mosquitos in all 159 counties.
When grouped by their habitat, mosquitos fall into three categories:
permanent pool, floodwater or temporary pool, and container. The
aggressive Asian tiger mosquito is a container mosquito, laying
its eggs in water that accumulates in tree holes, bird baths, buckets,
pet dishes and tires.
"Mosquitoes must have water to complete their life cycle,"
Womack said. "They lay their eggs in water or where water will
pool, such as old tires lying in someone's backyard. Mosquito larvae
feed on microscopic organisms and complete their development in
In the South where mosquitoes are common pests in the hot, humid
months, why does the Asian tiger mosquito warrant so much attention?
These mosquitoes transmit dengue, which causes fever, headaches,
muscle pains, rash, nausea, vomiting and chills. In its most severe
form, dengue fever can lead to internal bleeding and death. Like
pneumonic plague, Bengal cholera, Hantaviral infections, cryptosporidiosis,
hemorrhagic fever and E. coli 0157, dengue is one of the emerging
diseases that have become world health issues, according to Womack.
A Full Schedule
A native of Anna, Ill., Mike Womack was 12 when his family moved
to Mississippi. At Hattiesburg (Mississippi) High School, he met
his wife, Sylvia, who now is an assistant professor of nursing at
Macon State College.
Womack received his bachelor of science and master of science degrees
in biology and science education from the University of Mississippi.
Coincidentally, he did his master's research on disease-transmitting
mosquitos. While completing his doctorate at the University of Southern
Mississippi, he learned of a teaching position in Macon State College's
Division of Natural Sciences and Mathematics. He joined the faculty
The biology professor's teaching schedule is full. In addition
to his normal course load at Macon State, he occasionally offers
a non-credit course on "Emerging Diseases, The Media and The
Public" in which he covers the global ecology of representative
emerging diseases and the accuracy of information transmitted to
the general public. He is director of an arthropod ecology lab,
which he established at Macon State 10 years ago with grant funds.
He also has taught microbial physiology and biology at the Georgia
Institute for Technology, and he is an adjunct assistant professor
of public health at Mercer University's School of Medicine.
Michele Wright of Elko asks Dr. Mike
Womack, center, about an assignment in his Biology 1101 lab.
A 35-year member of the Air Force Reserve, Womack serves as a major
in the Reserve's Biomedical Science Corps. Earlier this summer he
spent two weeks at Robins Air Force Base training personnel on how
to combat potential mosquito infestation on the 8,722-acre base.
"We're still tracking the Asian tiger mosquito in Georgia,
but now we have a brand new ball game -- the Asian bush mosquito,
which was discovered in New Jersey about two years ago," said
Womack, who is a member of the Georgia Mosquito Control Association
and the American Association of Mosquito Control.
The Asian bush mosquito can transmit the West Nile virus, which
Womack predicts will makes its way to Georgia by the end of this
summer. He is a member of a West Nile Task Force for Georgia, which
is developing a state response plan to the virus.
The West Nile virus first appeared in Uganda more than 70 years
ago, and since then outbreaks have been reported in Africa, Europe,
the Middle East, Russia and India. The first cases in the U.S. were
reported in New York City in 1999, and so far, the virus has spread
to 13 states, including North Carolina and Florida.
Georgia's West Nile Task Force team is conducting what Womack calls
passive surveillance, "looking for symptomatology in hospitals
and clinics and asking health departments to collect reports of
Birds are the reservoirs for the virus. "Humans can get infected
because the ticks and mosquitoes that feed on infected birds also
feed on humans," Womack said. "We know the Asian bush
mosquito transmits the virus, and we believe the same is true of
the Asian tiger mosquito." Symptoms of West Nile virus are
similar to influenza and if untreated can develop into encephalitis.
How can we protect ourselves from these disease-spreading mosquitoes?
"Keep your yards clean," Womack advised. "Make sure
there is no standing water in your yard. Empty buckets. Keep pet
bowls and bird baths clean. Take care of out-door drainage problems."
Work Is Never Done
In May 2000, Womack was one of three Georgians serving on a 60-member
committee representing the American Mosquito Association (AMA) who
headed to Washington, D.C., to solicit funding for additional mosquito
research. The committee briefed Congress members on the threat of
the West Nile fever and the need for supporting recent laws aimed
at enhancing mosquito surveillance in 19 eastern states. The arrival
of the virus into the northeastern U.S. demonstrates how easily
emerging infectious diseases can travel into new geographic areas,
Following the committee's visit, the U.S. Health and Human Services
(HHS) secretary announced that an additional $5 million would be
provided for states to expand the surveillance activities for the
West Nile virus, thus doubling the Centers for Disease Control and
Prevention's fiscal 2000 funding for the project. Womack explained
that the additional funding from Congress goes from HHS to the Centers
for Disease Control in Atlanta, which then filters the funds to
district health departments in states where West Nile virus outbreaks
Meanwhile, Womack continues to survey mosquito populations in the
Southeast and to educate the public -- via his classroom lectures
and international presentations -- about mosquito-borne viruses.
In this age of emerging infectious diseases, a disease vector ecologist's
work is never done.