DiniMiller-BedBugsLearning

8/7/2019 DiniMiller-BedBugsLearning

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Bed Bugs:

What we are

Learning

Dini M. Miller Ph. D

Associate Professor andUrban Pest Management

Specialist

Virginia Tech

Blacksburg, VA 24061

Bed Bug Appreciation

Family Cimicidae

Originally cave dwellers

(Middle East) that were

ecto-parasites of bats

umans move nto t ecaves so bed bugs started

to feed on humans

Humans have

transported bed bugs all

over the world Piercing-sucking mouthparts

US History of the Bed Bug

Common pest in theUS at the turn of thecentury

Essentially eradicatedin 1940-50 due toDDT

Resistancedocumented to DDT,malathion,

carbamates andpyrethroids

Why are Bed Bugs Spreading?

International travel?

Lack of bed bug

awareness?

Misidentification?

ncrease pressure o

resistant populations?

No treatment except

fumigation delivers

100%?

Cost of control? World-Wide Resurgence

Poultry Farming? We Did Not Know How to Treat

At first, we treated themlike cockroaches.

Gangloff-Kaugfman et al. 2006survey of pest controlcompanies

98.6% makin crack ancrevice applications (liquidor dust)

67.9% used sticky traps

92.3% used liquid spray onbaseboards, floors and othersurfaces

40% never used aerosols orgeneral dusting

MaxForce Gel bait on mattresses


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Why Are Bed Bugs Problem?

Overwhelminglypyrethroids, were theinsecticides of choice

IGRs were used incombination with

pyrethroids

Steam, heat, freezing,and mattressencasements were notused by mostcompanies.

Bed bugs found in box springs andmattresses >94 % of the time.

So What Are They Doing? Aggregate in cracks and

crevices all day

If hungry they becomeactive between midnightand 5:00 am

Stimulated b and

increase of CO2 in theroom

Will travel many yards toget to a host

We still dont knowexactly how a bed bugfinds the host

80

90

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saggregated

FED Males

UNFED Males

Onset of

PhotophaseScotophase

Nocturnal Activity

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Meanpercentof10malebedbu

inshelter

Bed Bug Feeding

Probe the skin to find a

capillary space that allows

the blood to flow rapidly

May probe the skin several

mes e ore ee ng.

Feeds for 5-10 minutes

After feeding, leaves the

host to aggregate

Bed bugs usually feed every

3-7 days

Feeding Behavior

Most of the time, themajority of the populationis in the digesting state.

Old literature claims thatadults live for a 1 yearwithout feedin .

However, recent researchindicates that all life stageslive only ~70 days withoutfeeding

However, they can livelonger at cooltemperatures


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Right After Feeding?

Right after adults take ablood meal they becomevery interested in mating,particularly the males.

They engage in traumatic

insemination.

The male stabs hisparamere through thefemale wall

We have seen females beginto produce eggs within oneday of mating.

Consequences of Mating The females body must

heal from this wound

Females are known to leave

aggregations after being

mated several times.

e process o ea ngfrom mating has an impact

on the females ability to

produce eggs.

Females that mate only

once will produce 25%

more eggs than females

that are mated repeatedly.

Will mate when skinny as well.

Egg Production: Single versus Multiple Mates

5th feeding

4th feeding

3rdfeeding

66.7

56.9

40.6

2nd feeding

1st feeding

48.641.2

34.4

P=0.0019

27%

decrease in

production

Authors: Andrea Polanco and Dini Miller

Why do you care? A single mated female

brought into a home cancause an infestationwithout having a malepresent

ust ave regu ar oomeals

The female willeventually run out of

sperm. She can mate with her

own offspring after theybecome adults.

Egg Production

The total number of eggsa female can produce is

dependent on feeding

frequency

After takin a blood

meal the females

produce 5-20 eggs over

the course of 10 days

She will not reproduce

again without feeding

Resistant females

produce fewer eggs

These eggs are about to

hatch ( ~5 days old).

You can see the eye spots

of the developing nymphs.

Cumulative Mean Number of Eggs

Produced (Resistant vs. Susceptible)

40

50

60

feggs

Susceptible strain (Harlan)

Resistant strain (Richmond)3 rd Feeding

~55

-10

0

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1 3 5 7 9 11 1 3 15 17 1 9 21 2 3 25 2 7 29 31 3 3 35 3 7 39

Days of egg production

Cumulativenumber

1st Feeding

2 nd Feeding

P


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Population Growth

Eggs can be laid singly or in groups

About 97% of all eggs will hatch successfully

Each female will be replaced by ~35 reproducingdaughters

Females in the laboratory begin to die after about9 feedings

Average females produces ~113 eggs in herlifetime

Under optimal conditions the population candouble in ~16 days

Egg Hatch Time

Our labobservationsindicate that about64% of the eggshatch between

days 6 and 7.

Greater than 90%are hatchedbetween days 8-9.

Temperature willinfluence hatchtime

Hatching bed bug nymphs

Nymph Survivorship

The first instars (newly

hatched nymphs) will

need a blood meal within

~ 3 days before they start

to die.

The early death is most

likely due to dehydration

(moisture loss) rather

than starvation.

Many first instarsprobably die because

their egg was laid too far

from a host.

What is the bed bug lifecycle? Bed bugs go through 5

nymphal instars before

they become adults

Each instar must have

the next stage (5-8

days)

If no host present it

does not molt First instar to adult in

~37 days

Fed and Unfed Nymphs

Incomplete blood meals and

starvation will prolong

development

Adult Life Span

An adult bed bug at >70o

F will live between 99 and200 days (laboratory).

We do not know how longa bed bug will live insomeones apartment(several months).

Conditions are tough inhuman dwellings (findingfood, temperature andhumidity, insecticides,being crushed etc.)


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The Signs of Bed Bug Presence

Bed bugs have to bebrought in Traveling

Used furniture

First indicator is

unexplained itchingred welts

Bites suggest bed bugsbut are not definitive

Medical doctors areterrible aboutdiagnosing bites!

Bite Reactions (the first indicator)

My technicians armone week after feeding1000s of bed bugs.

My arm one week

after feeding 60 2-

3rd instar bed bugs.

My students arm 1

year after feeding

mixed stage bed

bugs.

Bites

One study found only 30%

had a reaction when bitten

by a bed bug.

Another study indicated

that 96% (of refugees in

Sierra Leone) had

.

Reaction will vary

depending on your immune

system and number of bites

More evidence is neededthan bites to confirm be

bugs

Bed Bug Evidence

Fecal spots (bed bug

poop).

What color is it? Let

people know.

Looks like cockroach

feces but feels very

different

Bed Bug Evidence

Molted skins (exuvia)

The molted skins can be

found in bed bug

aggregations or by

themselves

In a new infestation, bed

bug evidence may be very

hard to find. Yet, because

a large percentage of any

bed bug population is

immature, there is always

potential to find molted

skins.

Hard to Find but Obvious


6/9

Bed Bug Basics: Social Issues

Bed bugs still have a stigma

Everyone wants to blame or have someoneelse pay for the problem

management finding out

Hotels worry about the internet reviews

It has been slow trying to get community-wide bed bug programs started

Other people are obsessing about bed bugs

Health Issue: Stress Stress (after an infestation)

Sleeplessness

Medical bills

Destruction of self-image

Throwing out all belongings

Movin

Legal action

Stress (no infestation)

Waking family members in themiddle of the night or pullingout the furnace

Moving, and moving andmoving!

Social Issues: Lawsuits The questions:

Did the landlords do enough to control the

infestation?

Did the hotel know they had an infestation?

Was there a prevention program in place?

Claims:

Damage

Injury (bites)

Emotional stress

Legislation

San Francisco passed Directors Rules andRegulations on how to Control Bed bug infestationArticle 11, Sec. 581 of Public Health Code on Sept.1,2006 Property Owners and Operators shall not have a public

nuisance on the property

Tenants must clean and cooperate with owners and PCOsor be cited

PCOs have guidelines for inspection and treatmentprocedures

2009 Virginia HB 2080- Landlord is to maintain fit

premises. Tenant shall prepare the dwelling forpesticide application according to managementinstructions. If insects are found

Other Social Issues

Rise in low-incomeinfestations where peoplecannot afford control

Language barriers, hiding,denial, lack of literacy arecontributin to the s read

Resident using andmisusing their owninsecticides

EPA is particularlyconcerned about non-registered insecticidesbeing purchased over theinternet

On-Line Products

Most products willkills some bed bugs ifyou spray themdirectly.

not realize that killingbed bugs you can see isnot the problem.

Our problem isstopping theinfestations.


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Integrated Methods

Used in combination

with chemical methods

Treatment preparations

Monitoring with dogs

Passive monitors Vacuum

Steam

Mattress encasements

Extreme temperaturesPrevention: No furnishings from the

dumpster

Working with the Customer

Plastic bags provided

for the customers to

bag and seal their

belongings so the room

Showing customers

where to inspect for

bed bug eggs etc.

Pest Control operator

and customer work as

a team

You cannot touch the students

belongings in a VT dorm room

Monitoring Device: Dogs

Used in hotels

Excellent detectors

As of 2008 can

distinguish between

live and dead bed

bugs

Good for lawsuitdefense

Jada sniffs for bed bugs in Manhattan

Climb-Up

Device Used for detecting

small infestations(early detection)

Prevents fed bugs

Detects bed bugs thatmay be enteringadjacent units

Can catch enough bedbugs to reduce thepopulation

Vacuuming

The value of vacuuming isthat it makes inspections

easier.

In large infestations, bed

bug harborages are not only

filled with live bed bugs, but

also with dead bed bugs,

molted skins, hatched egg

shells, and feces.

It is often difficult to

distinguish what is alive

from what is dead in a messy

harborage, particularly after

treatment.

Steam Cleaning

Steam temperature(at the bed bug) mustbe 135o F (54o C) orgreater

The steam head mustbe large

Steam power will killbed bugs and theireggs (1220 F)

Steaming is slow andlabor intensive

Upholstery and bedding can

disperse steam heat

Thermal death point 48oC


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Cryonite

Bed bugs exposed to CO2snow at -108o F. The snowmixture is blown out apressurized cylinder througha nozzle that forms vapors.

The pressurized snow freezesthe cells of the bed bug

This system will noteliminate a bed buginfestation if used alone.Other control methods willstill have to be used.

Diatomaceous Earth

Diatomaceous earth (DE) is a desiccant dust made

of the silica-based skeletons of microorganisms

called diatoms. This dust kills bed bugs by sticking

to the outside of their bodies and absorbing the wax

layer that keeps them from losing their bodymoisture. The bed bugs desiccate and die within a

couple of days.

Do not use the pool filter DE it has been heat

treated and is an inhalation hazard

Mattress Covers

Encasements for both

mattress and box

springs!

Im roved version has

a zipper protector

sewn in

Traps bed bugs and

eggs, bite proof and

escape proofProtect-a-Bed

Not all covers protect

Where the zipper closes and the zipper teeth

are vulnerable to bed bug escape

Whole Home Heat Propane or electric.

Temperature ~132F, fans

turned on to heat items in

the room to 120F.

Heat Chambers

Do it Yourself

Pack Tite


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Summary

Bed bugs biology and behavior contributes to theirsuccess as a pest

We must be able to recognize the signs of aninfestation early on to deal with bed bugs effectively

We must understand the social issues re ardin bed

bugs, and be able to work with those issues

We must be in acceptance that (right now) there isnot single insecticide product that capable ofeliminating bed bugs

We have treatments that work but all are timeconsuming and expensive.

The Future

Current insecticides do not work as well as we

would like, so we will see more use of alternative

methods (heat, fumigation, clutter removal, mattress

covers, and vacuuming).

professionals (not just applicators but consultants)

New legislation

More bed bug infestations and insecticide

misapplications due to the cost of control.

Housing authorities are all talking bed bugs!

http://www.vdacs.virginia.gov/pestici

des/bedbugs-facts.shtml

Google: VDACS Bed Bugs

Biology and Behavior

Identification

Personal prevention

Apartments

Hotels

Shelters

Emergency facilities

Schools

Home health care workers

What to expect during a treatment

Heat treatments

Chemical

Non-Chemical

Questions?

Documents

DiniMiller-BedBugsLearning