Fly Management

Announcements

• Speaking today: Ashlee Swinford; No speaker on Thursday

• Next Speaker: Carolina Escomilla on Tuesday, Nov. 10.

• Recognition

Important Seminar Friday

• Phil Lounibos (Univ. Florida) – Student Choice Speaker 3pm, N-12 Ag. Sci. North

• Speaking on the ecological interactions between Asian tiger mosquitoes (Ae. albopictus) and yellow fever mosquitoes (Ae. aegypti).

• Has conducted extensive work on Aedes aegypti in Florida, Colombia, & Brazil.

• Current projects.

Exam Review - Material

• Material Covered for the Exam: Lecture & Reading material THROUGH today. – Lecture material– Text Readings (Chaps 11 (from ca. p. 157),

12, 13, 14, 15, 16, 17, 18, & 19 (about 200 pp of material)

• 5-min Presentations NOT Covered

Exam Review – Similar Format

Exam will have 3 General Parts – Somewhat longer than the previous exam

1. Picture Questions• Five or so picture questions, pictures will change

every 15 sec. or so.• For each picture, there will be 3 – 5 questions.

2. Non-Picture Questions• About 20 multiple choice or “check all that apply”

3. Short-Answer• 5 – 10 questions that can be answered in a

sentence or two.

General Study Guide - 1

• What insects have been discussed so far (common names only)?– To what orders/families do they belong? Families are

important only if there are very few in the order, e.g. Diptera/Psychodidae/Phlebotominae

• Which pathogens/diseases do these insects vector?– What is the transmission pathway?– What are the symptoms of the disease?– What type of pathogen is it? (e.g. bacteria, virus,

protozoan, rickettsia, etc.).

General Study Guide - 2

• For each insect/pathogen combination:– How prevalent/serious is the threat? – What host-pathogen-insect factors are

involved in the transmission-disease cycle?– What general categories/terms apply to the

various components?– In what situations would you expect to

encounter the problem (geographical location, season, ecological setting, specific sites/times of day, etc.).

– What are the general management options?

General Fly Management

• Most fly management is host/site-centric with key disease/problems being the management objective(s)– e.g. Livestock fly management focuses on

stable/face/horn flies, cattle grubs– e.g. Urban fly management focuses on

mosquitoes & human disease reduction– Hospital fly management focuses on

filth/house fly exclusion & elimination

Generic Fly Management Components

• Fly management programs are generally divided into larval and adult components.

• Vectored pathogens generally managed pharmacologically with prophylactic treatment used where available.– Therapeutic treatments not always available.– If available, therapeutic treatments are often expensive, have

multiple contra-indications, not always well tolerated.– Disease diagnosis means damage has already occurred

• For humans, education component is important.• There may be a disease/fly reservoir management

component as well

Larval Fly Management

• Source Reduction – Elimination of larval habitat and/or resources

• Biological Control – Use of one organism to control another. Pest target is usually a future generation.– Conserving existing biological controls– Augmenting existing biological controls

• Chemical Control – Contaminating larval habitat with an agent toxic to the larva.– Agent may be chemical or biological– If biological, pest target is usually the current

generation.

Source Reduction for Larval Control

• Reducing standing water• Reducing fecal material,

rotting vegetable material• General sanitation

Stable fly breeding ground

Fly swarms in Cambodia garbage

Draining standing water in California

Biological Control via predators, parasites

• Some are commercially available (e.g. Muscidifurax raptor for house fly control).

• Major emphasis of mosquito management in rice lands

• Some cases of entomopathogens managed for larval control

Above: Muscidifurax parasitizing fly pupae (left) and empty pupal cases after paratization

Above: Fly maggot infested with parasitic nematodes that are killing the maggot.

Mosquito Fish

Key is conservation

First introduced from Asia into the US during the early 1900’s

Several species, most are tropical, there are some winter hardy species.

Specialized for mosquito predation.

PathogensMany are known, few are actually managed for mosquito control

Lagenidium water mold

Mermethid Parasite

Picornavirus

Chemical Control (Insecticides),

• Applied to larval habitat• Non-parasitic larvae: General

environmental application for typical insecticides

• Parasitic Larvae: Oral/Dermal/Suppository/Parenteral application of avermectins (vertebrate systemics)– Synthetic analogues of a soil microbial

extract found in Japan, 1978

Larvicides for Free-Living Larvae

• Nerve Poisons – Interfere with nerve action, larva can’t swim/orient/breathe, cause of death usually asphyxiation (anoxia) or dehydration

• Insect Growth Regulators – Interfere with the ability to grow and molt

• Microbial Insecticides – Infectious units of a pathogenic microbe, targeted at the existing generation

• Smothering Agents – Prevents respiration, cause of death is anoxia, mostly for aquatic larvae

Nerve Poisons as Larvicides

• Originally, organochlorine, organophosphate, & carbamate insecticides. Those aren’t used anymore.

• Primary nerve poison now are spinosyns, synthetic analogues to spinosad.– Originally found in Jamaican rum barrels in 1982.– Produced by a soil actinomycete, Saccharopolyspora

spp (now several species)– Naturally-occurring blend of several compounds (esp.

spinosyn A & D), along with many other components.

Spinosyns for Diptera Control

• Different mode of action from other nerve poisons (mostly used on adults)

• Wide use in agriculture• Can be used in rotation with other

larvicides• Classified as “Reduced Risk”• Active area of work with new

applications still being found.– e.g. promotion of wound healing.

Larvicides:Insect Growth Regulators

• Methoprene is the most common.

• Advantages – Harmless to non-insects, inexpensive, rapid acting

• Disadvantage – no additional effect on adults, affects other insects (including beneficials)

• Examples• PreStrike Granules

• Methoprene is the most common.

• Advantages – Harmless to non-insects, inexpensive, rapid acting

• Disadvantage – no additional effect on adults, affects other insects (including beneficials)

• Examples• PreStrike Granules

Larvicides: Microbial AgentsBacillus sphaericus & Bacillus thuringiensis israelensis (Bti)Bacillus sphaericus & Bacillus thuringiensis israelensis (Bti)

• Advantages– Non-target Safety– Control for 30+ days

• Disadvantages– Short window of treatment

opportunity– May have disagreeable

odor/appearance

• Examples

– Mosquito Dunks

– Mosquito Quick Kill Granules

– VectoLex

• Advantages– Non-target Safety– Control for 30+ days

• Disadvantages– Short window of treatment

opportunity– May have disagreeable

odor/appearance

• Examples

– Mosquito Dunks

– Mosquito Quick Kill Granules

– VectoLex

Larvicides: Physical Smothering Agents

“Suffocates” mosquito• Advantage:

– Also acts on pupae and ovipositing adults

– Can be used to treat very large areas

• Disadvantage:– Oil film– Subsurface larvae

• Examples:– BVA, Golden Bear– Agnique (monomolecular)

Adult Fly Management

• Personal Protection

• Exclusion (buildings, small areas)

• Insecticides– Residual– Non-residual

• Other– Trapping in sensitive areas– Mating Disruption

Personal Protection

• Stay indoors at dusk & during evening hours

• Long shirts and pants• Repellants

– Deet: • N,N-diethyl-metatoluamide• 30%

– Non-deet: • Eucalyptus oil • Avon Skin-So-Soft• Citronella oil

Repellents – Two TypesPersonal Small Space

Protects a single individual

Effective Range ~ 1 foot

Protects a small group of people

Effective Range ~ 10 feet

Mechanical Exclusion

• Shut them out

• Netting and Screening– 16-18 mesh

Adulticides

• Nonresidual Area Sprays– Contact insecticides, droplets must make

direct contact with mosquito

• Dominant Products– Sumethrin + PBO (Anvil)– Resmethrin (Scourge)

Non-residual adulticiding is used for large-area space treatments using

ULV equipment• ULV = “Ultra Low Volume”

– Very small droplets;8 to 30 microns

• Prefer low air currents:– 3.2 kph to 12.9 kph– Excessive wind & updrafts

reduce control but some is necessary for dispersal

• Disadvantages: – Gets everywhere: in

residences, on food, etc.– Expensive– Products may act by temporary

repellency

Perimeter treatments use residual pyrethroids

• “Pyrethroids” synthetic derivatives of chrysanthemum extracts•Advantages

•Provides weeks of control• Residual but do not move in the food chain

• Disadvantages• Extensive non-target arthropod effects• Fairly expensive