Heather Margetts
Bio 1610
Research Paper
HANTAVIRUS
Introduction.
Viruses can be transmitted in many ways, through body fluids, dirty handles, and
through the air. It is the rare virus that can be transferred from one species to another.
One such virus is Hantavirus. Hantavirus is a very social virus and can be found across
the globe. It is carried by various rodent species. In environments where rodents and
people live together the virus can jump species and infect humans, causing nephropathia
epidemica with renal syndrome (NE) making them very ill with a possibility of mortality.
From 2009 to 2011 a research project was carried out in Belgium to discover the
correlation between host rodent populations and rates of infection in humans. The
researchers carried out the field (literally) experiment for two years on the outskirts of
Brussels. They examined three groups of rodent populations and the rates of the virus in
them. They gathered vital statistics on the critters such as: sex, weight, whether they were
captured in the spring or autumn, age, and the location of the capture. All to discover the
relationship between rodent populations and NE infection rates.
Methods.
There are two different migrations of rodents in the area surrounding Brussels,
one in the spring when they head out to mate, and one in the fall as they return home to
hunker down for winter. The research team took advantage of these predictable
movements in order to analyze the size of the rodent populations and the specifics of the
carriers of the virus. They wanted to discover the leading factors involved the movement
of Hantavirus hosts and the possible causes of involved in its transmission.
On the outside of town the researchers set out traps to capture the bank voles,
wood mice, and rats, along with the occasional owl or fox. Painstaking statistic collection
was carried out with information about the capture, especially seroprevalence of Puumala
Hantavirus, which causes hemorrhagic fever in humans. Species, size, weight, repeat
capture count, and many other data points were used in their analysis of the rodents and
virus.
Results.
Hanta virus is a socially transmitted virus in rodents and humans. When
populations of voles become dense, the Hantavirus seroprevalence rates become elevated.
Its highest rate in the study shows that nearly 60% of voles will be carrying the virus at a
time. This is a heyday for Hantavirus and can occur when there are 140 or more voles
per hectare, or about 57 voles per acre.
The large, older male voles had the highest rates of Hantavirus. They also had the
largest home range, or home territory. Also the females with larger home ranges had
higher rates. Remember that Hantavirus is a social virus and the social butterflies, or
males looking to mate, are much more likely to be exposed to the virus.
This phenomenon has another side to it. The voles who are more willing to travel,
for whatever reason, are also much more likely to cross paths with humans. And so, the
rodents who are most likely to carry Hantavirus are also the most likely to bump into our
cities. In the end there is a positive correlation between virus carrying rodent populations
and human infections.
Discussion.
“This two-year study showed that bank voles were common at all three suburban
sites studied and that Hantavirus was detected in voles at least at one site during each of
the four capture seasons.” (Dolby, A, Journal of Vector Ecology, Spatiotemporal
dynamics of Puumala hantavirus in suburban reservoir rodent populations, Dec, 2012).
There is a potential threat to public health due to these vector populations. With this
research there is data to point to in order to mitigate the possible infection of human
populations.
The team’s research seems to confirm the somewhat commonsense hypothesis
that as rodent populations go up, so do the rates of human hanta virus infection. This was
a medium length research project, and their data is still restrained by the relatively short
time frame. But, this is valuable information. It could be used to enact public policy such
as the Nature Conservation Board of the Brussels Region. This data could funnel money
into more projects to monitor specific risky species in order to protect the public. If
effective in Brussels, similar practices could be put in place the world over to protect the
health of people everywhere.