Two representatives from the Clackamas County Vector Control District
(CCVC), Interim Executive Director Josh Jacobson and office manager Theresa
Micallef, detailed methods used to monitor and control mosquito populations
on the mountain at the Tuesday, Feb. 6 meeting of the Mt. Hood Area
Chamber of Commerce, held at the Mount Hood Village RV Resort. They also
informed citizens of ways to reduce exposure to potential mosquito borne
illnesses such as West Nile and Zika viruses.

“We’re trying to have the minimum impact on people, property and the
environment,” Jacobson said, describing an approach called integrated pest
management, “while protecting citizens from mosquitoes.”

CCVC was established as a special district in 1964 to control mosquito and fly
populations that act as vectors, or carriers, of pathogens such as viruses,
bacteria and harmful protozoans.

Jacobson explained that limiting breeding grounds is an essential aspect of
control in which community members can play an important role. Mosquitoes
breed in any containers that hold still or stagnant water such as bird baths,
gutters and downspouts, tires, planters, rain barrels and ditches.

Unmaintained backyard pools are cited as leading breeding grounds in the
area.

CCVC also reduces mosquito populations by providing any citizen with a
contained body of water on their property with free Gambusia affinis,
commonly known as mosquito fish. These minnows primarily feed on
mosquito larvae. This method can also help minimize the use of pesticides.
They advised community members to avoid exposure to mosquito borne
illness by limiting contact when mosquitoes are most active, during sunrise,
sunset and early evening. Jacobson recommended covering up with long
sleeves, long pants, socks and closed shoes when around mosquitoes and
using repellent containing DEET when necessary.

The West Nile virus is the primary mosquito borne illness of concern for the
CCVC. The virus produces flu-like symptoms in most cases but can result in
more severe complications for susceptible populations, including those with
compromised immune systems, the elderly and children.

The Oregon Health Authority (OHA) reported West Nile virus in six Oregon
counties in 2017, while no occurrences of West Nile virus were reported in the
Mount Hood area in 2017 according to the study. CCVC traps mosquitoes in
the region and tests potential vector species for the virus.

CCVC also watches for Zika virus, which was reported in the continental
United States in 2016. OHA reported that neither of the two species of
mosquitoes known to transmit the virus (Aedes aegypti and Aedes albopictus)
has been detected in Oregon, while Jacobson confirmed that these species
have not been discovered in the area by mosquito population monitoring.

Mosquito populations in the region increase steadily through the spring
months before peaking in July and August and decreasing in the fall,
according to CCVC monitoring data. As locals and tourists enjoy Mount Hood’s
myriad summer offerings, controlling populations is a shared concern.

Mount Hood Area Chamber of Commerce President Coni Scott described the
Feb. 6 meeting as well attended and reported a high level of interest from
local community and business members.

Additional information about methods mountain area residents can use to
prevent and limit their exposure to mosquitoes and mosquito borne illnesses
is available on the Clackamas County Vector Control website at