8
UWI TODAY
– SUNDAY 11 AUGUST 2019
RESEARCH
MOSQU
Takes Up
B Y A M Y
For many of us, mosquitoes are a daily annoyance,
and
one that we would happily stay far away from for the rest
of our lives. But Renee Ali looks at these flying nuisances a
little differently. A self-proclaimed “Mosquito Girl”, Renee is
one of a devoted team of local researchers who are studying
these tiny flying vampires to find out more about where they
live, what they eat, and how we can better protect ourselves
from the many diseases they carry.
Mosquito research in Trinidad has a rich legacy passed
down by the late Professor Dave Chadee— known to many
as the original “Mosquito Man”. Ever been on a plane and
saw the flight attendants spraying the cabin before takeoff?
You have Professor Chadee to thank for that, as he was
responsible for implementing the spraying to cut down
on the spread of mosquitoes across countries (by hitching
a ride on planes). His contributions to mosquito research
have helped people across the world to better understand
dengue fever, yellow fever, malaria and Zika, and many of
his students have gone on to make incredible discoveries
in the field.
“When Professor Chadee died, I didn’t know what to
do because I was his last student. I was basically like the
baby. I had just applied to do my PhD and just got accepted
when he passed away a few months later. I thought I was
going to (research) water with him. But everybody but me
knew he had this plan,” says Renee. She never expected to
be working with mosquitoes— after all, her background
is in molecular biology and she had originally expected
to work with Professor Chadee. But fate and the professor
had other plans.
Three years later, Renee is close to completing her
PhD studying the little-known Mayaro virus and its main
mosquito vector—a mysterious species called
Haemagogus
janthinomys.
Unlike its famous relative
Aedes aegypti
, not
much research has been done onHaemagogus and the virus
it carries. Twenty years ago, Professor Chadee and the Insect
Vector Control Division (IVCD) did some investigating —
focusing on the capacity of the mosquito species to spread
yellow fever and hunting for it in the wild anywhere there
were howler monkey populations (as they thought that was
its preferred food source). At the time, they didn’t know
about its connection to the Mayaro virus, which had only
been isolated in Trinidad in 1954 in some forest workers
and not found here since, although there have been several
reports across South America.
Dr Judith Gobin, Head, Dept of Life Sciences
is extremely pleased that the seminal work that was
accomplished by the late Prof Chadee continues to be
expanded in the work of our postgraduate students such as
Renee. She is convinced that Prof Chadee would also have
been very pleased.
A LITTLE KNOWN SPECIES
AND THE VIRUS IT CARRIES
The trouble with Mayaro virus is that its symptoms are
strikingly close to dengue and the chikungunya virus, so it’s
proven hard to diagnose. But Renee has had some luck in
pulling back the shroud over this little-known disease and its
vector species. For two years she was in the field, travelling
across Trinidad to look for Haemagogus. “I did a map of
Trinidad, divided it into four sections and I sampled North-
East, South-East, North-West and South-West Trinidad.”
She found Haemagogus all over, especially in forested
areas where she also managed to find Mayaro virus present
in mosquitoes. They were abundant in secondary forests,
but to her surprise, a lot were found in mangrove areas as
well, which means they are adapting to new surroundings.
It was a learning process for Renee, who had never
done that type of field work before. The UWI “mosquito
team” had a hand in collecting the bugs and getting all the
data together— Lester D James, Brent Daniel, Rachel Shui
Feng, Nikhella Winter and Akilah Stewart were all crucial
to making the project work.
“At first I didn’t know what I was looking for and we
were figuring everything out on the go,” says Renee. “Insect
Vector’s lab team also really helped me. It was a huge
collective effort…. All the molecular biology work I was
doingwith themosquitoes—themosquito teamdidn’t know
how to do that. But I needed to get the mosquitoes first.”
Now at the tail-end of her research, Renee doesn’t
spend as much time in the field but she still makes sure
to check all her traps regularly to monitor the mosquitoes
living in the wild, as well as maintaining her lab-grown
colony. She shows me a paper with what looks like small
black pen marks all over it, but under a microscope they
are revealed to be mosquito eggs.
“I collect the larvae and breed them to adulthood. I
have over 1000 eggs here, so I now have to hatch them to
start another colony. We use tyre traps out in the field for
two weeks, and then we collect the water and the eggs.” Tyre
traps are a low-budget solution to gathering specimens—
cut a tyre in half and hang it from a tree with some water
inside. The mosquitoes love the dark spaces and still water,
so there’s always something to find when she goes in to
collect samples. But when she started out, she had to do
things a little differently.
“In the beginning I was using traps, but wasn’t
getting much success, so I thought maybe I’mdoing
somethingwrong—ormaybe they’re just not there,”
she says. But one day, she was visited by Professor
Chadee’s mentor, Dr. Elisha Tikasingh. “He said,
you’re going about it wrong… you have to actually
sit there and let them come to you to bite you. Just
look up into the sunlight around their biting hours,
and they will come to you
”. And it worked.The tried
and true method from the earliest days of mosquito
research still stands— they love human bait.
FROM STUDENT TO SCIENTIST
Dr Adesh Ramsubhag, a senior lecturer in the
Department of Life Sciences and the one who got
Renee to come back to do research at The UWI in the
first place, remembers her start as an OJT in the labs.
“She demonstrated her potential as a scientist, working
systematically and diligently to successfully extract high
quality DNA from challenging materials including asphalt
Renee’s first article, titled “Cha
of the Mayaro Virus Vector Hae
Indies” was accepted for publicati
(in July 2019) found out that she h
Young Investigator Award— Int
(granted by the American Society
Mosquito researcher Renee Ali checks a tyre trap for mosquito larvae.
A magnified view of
Haemagogus janthinomys
,
vector for the Mayaro virus
