History and practices of mosquito control in coastal Georgia.

1. Life on the Coast: The Necessity
of Mosquito Control
Rosmarie Kelly, PhD MPH
Public Health Entomologist
Georgia Department of Public Health
Atlanta, GA
rmkelly@dhr.state.ga.us
404-408-1207

2. Overview
• Saltmarsh, freshwater, and mosquitoes
• Brief history of coastal mosquito-borne diseases
• Mosquito control
– Some history
– Mosquito control today
– Some data
• Surveillance
– Why do it
– Some basics (field work)
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3. Coastal Georgia
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4. Saltmarsh
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5. 5

6. A CDC egg survey estimated that the dredge
spoil areas have a breeding potential of 100
million mosquitoes per acre.
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7. The coastal marsh is not a “bad” environment. Over 90% of
the salt marsh does not breed mosquitoes…only the high
marsh areas that trap water after extreme high tides or
significant rainfall; ie. the areas of the marsh that do not
flush with the daily tides.
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8. Mosquito Oviposition Habitat
• There are two general categories within which
mosquito breeding habitats exist:
– natural mosquito breeding habitats
– man-made mosquito breeding habitats
• Female mosquitoes lay their eggs either on water
or on soils that are periodically flooded.
• These breeding areas can be found in habitats
that exist naturally, such as within a pond or flood
plain, or in habitats that have been created by
humans, such as bird baths, water-filled tires, or
catch basins.
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9. Freshwater Habitats
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10. WHAT MAKES A MOSQUITO?
 A long piercing-sucking proboscis, with
scales on it!
 Scales on the wings and body
 3 basic body parts
 Head
 Thorax
 2 (=one pair) wings
 6 (= 3 pairs) legs
 Abdomen ~60 species are found in Georgia
~12 are actually a human problem
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11. Male vs. Female
Mosquitoes
male female
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12. Things Often Confused With Mosquitoes
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13. Larvae
(5-10 days)
Pupae
(1-2 days)
Egg
(2 days -
live ~1 month
months)
Life Cycle of Emerging
a Mosquito Adult
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14. WHAT DO THEY
EAT?
Plant juices & nectar
Females also need blood from other animals
14

15. WHY DO THEY NEED YOUR
BLOOD?
They use the blood to
help develop eggs
And now there will be more mosquitoes! 15

16. • Prior to the Civil
War, the fertile delta
bottomlands of the
lower Altamaha
basin were
cleared, drained, ban
ked and irrigated for
the cultivation of
rice, the primary
staple crop of the
Georgia and South
Carolina tidewater
section.
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17. 17

18. The marshy fields where rice was grown were breeding
grounds for mosquitoes carrying diseases such as
malaria and yellow fever. 18

19. The semi-tropical climate that made the Lowcountry such an excellent place for
rice production also made it vulnerable to the spread of malaria and yellow fever.
Anopheles quadrimaculatus is historically the most important vector of malaria in
the eastern United States. Many regions have natural populations of An.
quadrimaculatus with predominant populations occurring in the rice growing
regions due to cultural growing practices. Fresh water is regularly added to rice
fields. Anopheles quadrimaculatus oviposit soon after fresh water has been
added.
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20. What is Malaria?
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21. What is Yellow Fever?
Sylvatic cycle
Urban cycle
A mosquito-borne viral disease of
humans. Aedes aegypti is the
most common vector.
Initial symptoms include
fever, headache, vomiting and
backache. yellow fever had a mortality rate of ~80%
As the disease progresses, the
pulse slows and weakens, and Rural cycle
bleeding of the gums and bloody
urine occur.
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Jaundice may also occur.

22. Even in the absence of
diseases, mosquitoes can become so
abundant that they cause disruptions in
community services and cause severe
stress in the affected local human, pet
and livestock populations.
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23. History of Mosquito Control
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24. In 1817 the City of
Savannah, which also
supported a large rice
growing
culture, approved an
ordinance authorizing
the City to buy the right
of culture from wet to
dry from the
surrounding
landowners.
From 1817 to 1829 the City records show the health of its citizens was
City had expended much improved.
$72,537 so that only dry
rice field culture would This successful reduction in mosquito
be practiced on the breeding sites was likely the first time
adjacent lands. that local tax monies were expended to
control mosquitoes in the New World.
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25. Mosquito-control operations are targeted against three
different problems:
• Nuisance mosquitoes bother people around homes
or in parks and recreational areas;
• Economically important mosquitoes reduce real
estate values, adversely affect tourism and related
business interests, or negatively impact livestock or
poultry production;
• Public health is the focus when mosquitoes are
vectors of infectious disease.
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26. To successfully control mosquitoes it is important to know:
1. Which mosquito species are locally
important as the primary source of
intolerable annoyance or as vectors of
disease.
2. Where the breeding sites of these
mosquito species are located.
3. When the mosquitoes are developing
in these breeding sites and when the
emergence of adult mosquitoes will
take place.
4. What mosquito control measures are
needed and can be applied
effectively, economically, and safely
with minimal disruption to the local
environment.
5. How much funding will be required
to coordinate and execute the plan. 26

27. INTEGRATED MOSQUITO MANAGEMENT
"A process consisting of the balanced use of
cultural, biological, and least-toxic chemical
procedures that are environmentally compatible
and economically feasible to reduce pest and
disease-vector populations to a tolerable level"
THIS DOES NOT IMPLY THAT PESTICIDES SHOULD NOT BE USED
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28. Best Management Practices
Integrated Mosquito Management
Surveillance
Source Reduction
Adult and/or Larval Control
Community Education
Mapping / Record Keeping
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29. Without surveillance, mosquito control becomes a
matter of luck.
With surveillance, mosquito control becomes more
targeted, more effective, and more economical.
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30. Source Reduction
• Modification of water
habitats, including:
– Ditching
– Clearing vegetation
– Filling low areas
– Emptying containers
– Cleaning gutters
• This is the best method
to use when dealing with
container breeding
mosquitoes.
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31. Larviciding
• Larviciding is a general term for killing
immature mosquitoes by applying
agents, collectively called larvicides, to
control mosquito larvae and/or pupae.
• It can include the use of natural enemies:
– Dragonfly naiads
– Mosquito Fish (Gambusia)
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32. Some Larviciding History
• Waste oil or diesel oil products were implemented to
control mosquitoes in the early 1800s
• Paris green dust, an arsenical insecticide, was
developed as a larvicide in 1865 and, along with
undiluted diesel oil, was used through the 1960s
• Larviciding became prominent when implemented as
an area-wide malaria control procedure in the early
1900s
• After 1945, DDT, a chlorinated hydrocarbon
compound, was used as both an adulticide and a
larvicide - mosquitoes became resistant to DDT, and its
use was discontinued in the late 1950s
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33. Some Larviciding History
• In the 1950s, malathion, an organophosphate, was used
increasingly to control both larval and adult mosquitoes -
soon, resistance to malathion was observed in saltmarsh
mosquitoes.
• Products currently available for use in larval control include:
– Biological insecticides
• Bacillus sphaericus
• Bacillus thuringiensis israelensis
• Natular
– Temephos (OP)
– Methoprene (IGR)
– Oils
– Monomolecular films
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34. Adulticiding
• Control of adult mosquitoes using pesticides
• Products available for use include:
– Organophosphates
• Naled
• Malathion/Fyfanon
– Synthetic pyrethroids
• Adulticides can be applied using:
– ULV cold fogging
– Thermal fogging
– Barrier spray
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35. Controlling Adult Mosquitoes
• Time of day
Truck Mounted ULV
– Mosquitoes must be
Adulticiding present
– Dark or close to dark
– Temperature inversion
• Conditions
– The pesticide has to
impinge upon the
mosquito while aloft
– The pesticide has to
remain aloft but close to
the ground
• Calibration/Droplet size
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36. Public Education
• Media reports
• Community Programs
– Tip and toss (source reduction)
– Neighborhood cleanup
• Wear repellent (bite prevention)
• School programs
• Churches
• Nursing Homes
• Any place the public congregate
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37. Mosquito Control Education
• It is important to increase the knowledge of mosquito control workers and
other professionals on matters related to mosquito
biology, ecology, relationship to disease, and control.
• Georgia Mosquito Control Association
– Founded in 1977
– Annual meeting
– Support for mosquito control programs
– Sustaining member of the AMCA
– PESP member
• Georgia Department of Public Health
– Mosquito surveillance
– Mosquito ID classes
• Extension Services
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38. Record Keeping
• Logging and tracking of citizen complaints and
service requests.
• Mosquito collection and trapping.
• Insecticide applications and regulatory reports.
• Tracking of work assignments, including detailed
daily time and task recording.
• Virus testing (sentinel flocks, mosquito
pools, etc.) and related lab reporting.
• Mosquito breeding and trap site mapping.
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39. MAPPING
A picture is worth a
thousand words.
1. Map complaints
2. Map service calls
3. Map breeding sites
4. Map anything useful
and mappable
USEFUL TIP – Google Maps

40. Surveillance Data – McIntosh County
McIntosh County Mosquito Surveillance
species CDC Gravid
Ae. albopictus 5 9
CDC Gravid
Ae. vexans 2
70
An. crucians 47
An. quadrimaculatus 29 60
Cq. perturbans 7 50
count
Cx. nigripalpus 12 40
Cx. quinquefasciatus 1 64 30
Cx. salinarius 10
20
Oc. atlanticus 2
10
Oc. japonicus 1
Oc. sollicitans 27 6 0
Ae. vexans
An. crucians
Cx. salinarius
Oc. japonicus
Cx. nigripalpus
Cq. perturbans
Ps. columbiae
Ae. albopictus
Cx. quinquefasciatus
Oc. sollicitans
Oc. triseriatus
Oc. atlanticus
An. quadrimaculatus
Oc. triseriatus 1
Ps. columbiae 4
Oc. taeniorhynchus 8767 93
GRAND TOTAL 8914 173 Species
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41. Surveillance Data – McIntosh County
Surveillance Data
Ae. albopictus
Ae. vexans
An. crucians
An. quadrimaculatus
Cq. perturbans
Cx. nigripalpus
Cx. quinquefasciatus
98% Cx. salinarius
Oc. atlanticus
Oc. japonicus
Oc. sollicitans
Oc. taeniorhynchus
saltmarsh Oc. triseriatus
mosquito
Ps. columbiae
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42. Mosquito Surveillance
Gravid Trap
Light Trap

43. Mosquito Gravid Trap Operation
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44. Gravid Traps
• USE – primarily for monitoring container
breeding mosquitoes
• Used in the WNV surveillance program
• NOT USEFUL for monitoring most nuisance
species
• NOT USEFUL for monitoring EEE
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45. Mosquito Light Trap Operation
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46. Light Traps
• USE – general surveillance for
host-seeking mosquitoes
• Used in the EEE surveillance
program
• USEFUL for monitoring most
nuisance species
• NOT USEFUL for monitoring WNV

47. Larval Surveillance – “get them before they get you”
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48. WHY MOSQUITO SURVEILLANCE?
•Surveillance is used to define the nature and extent of the
mosquito problem.
•Surveillance is used to gauge daily mosquito control needs.
•It provides a basis for evaluating the effectiveness of control
operations.
•It provides a basis for evaluating the potential for
transmission of mosquito-borne diseases.

49. Mosquito Surveillance
Mosquito surveillance is the cornerstone of mosquito control.
No mosquito control program can operate effectively without a
surveillance program.
Mosquito surveillance can reveal:
•The species of mosquitoes that are active in a community
•The presence of disease vector species
•The presence of mosquitoes infected with arboviral diseases
•The breeding habitats of the local species
•The size of the local mosquito population
•When to apply pesticides to control the mosquito population.

50. Knowing what mosquito species are present and
where they are breeding is essential to a well-planned
mosquito control program.

51. ALL MOSQUITO SURVEILLANCE SHOULD HAVE A
PURPOSE:
•MOSQUITO CONTROL – LARVAL OR ADULT
•ARBOVIRAL SURVEILLANCE
•PUBLIC EDUCATION
MOSQUITO SURVEILLANCE SHOULD NEVER BE
DONE WITHOUT A SPECIFIC GOAL IN MIND.

52. http://health.state.ga.us/epi/vbd/mosquito.asp
http://www.GAmosquito.org
Any Questions?
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53. Field Work
• Adult surveillance - set traps
– CDC miniature light trap
– CDC gravid trap
• Larval surveillance
• Landing counts
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