Re-emergence of bed bugs in the U.S. Abelardo C. Moncayo, Ph.D. Vector-Borne Disease Section...

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Re-emergence of bed bugsin the U.S.

Abelardo C. Moncayo, Ph.D.

Vector-Borne Disease Section

Tennessee Department of Health

Historical perspective Bed bugs have plagued humans for thousands of

years

Origin of relationship remains unclear Originally a problem for the wealthy Enhanced by fire and heated homes Present in literature as far back as 400 B.C.E.

Decline of bed bugs

Three major factors:

DDT use in 1950s Improved vacuum cleaners Changes in home construction

Current status targeted pest treatments + bans, frequent travel have

led to a bed bug resurgence in the U.S. 300% increase in cases from 2000 to 2001 70% increase in cases in 2002 and 2003 Orkin had a 20% increase in bed bug calls in 2004 Reports of bed bugs in 43 states last year Chemical companies are reluctant to enter the bed

bug market because of failure to control Difficult to detect, to treat, and often to identify

Family Cimicidae : The bed bugs About 91 species in 22 genera

12 genera only parasitize bats 9 genera only parasitize birds 3 species parasitize humans

Cimex lectularius (worldwide) Cimex hemipterus (tropics) Leptocimex boueti (West Africa)

Other species of concern (may bite people) Bat bug (Cimex adjunctus) Swallow bug (Oeciacus vicarius) Chimney Swift Bug (Cimexopsis nyctalis)

Question of origin Humans in caves Bats in homes

Human-biting bed bugs

In Tennessee ??Cimex lectularius

Bed Bug

Cimex adjunctusBat Bug

Cimexopsis nyctalisChimney Swift Bug

Most likely 3 species

Oeciacus vicariusSwallow Bug

1 possible species

BED BUG

Identification Adults 1/4 to 3/8” long Brown to reddish brown Oval shaped Flattened Beak-like mouthparts Small, stubby,

nonfunctional wing pads “Obnoxiously sweet” odor

Habits

External parasites that feed on blood Humans are the preferred host !

However - also feed on birds, rodents, bats, pets Feed during the night with peak activity occurring

just before dawn Seek refuge during daylight in dark, protected areas Prefer dry fabric, wood, and paper surfaces Fast-moving

Injury Painless bite Reaction to the injected saliva

(individual variability) Swelling Rows of welts Severe itching (hours to days)

No conclusive evidence of disease transmission

Hepatitis BChagas’ Disease

Anxiety

Immediate Bite Reactions

Delayed Reactions (> 24 hrs.)

Life CycleEgg

Female can lay 1-12 eggs per day Deposited on rough surfaces or in

cracks and crevices Hatch in 6-17 days

Life Cycle

Nymph 5 instars Require a

blood

meal to

molt

Life CycleAdult May live for 12-18 months Total developmental time takes

21 days @ 86F and 120 days @ 65F

Nymphs and adults can survive for more than

a year without Food !!

Feeding - Several Instars

Engorged Nymphs-1 & 2

Engorging Adults & N - 2

Prevention

Don’t bring infested items into the home Inspect clothing and baggage of travelers Inspect secondhand beds, bedding, and furniture

Exclude alternative hosts (birds, bats, rodents, etc.) Caulk cracks & crevices in building’s exterior Repair or screen openings

Integrated Pest Management

(IPM) Correctly identify the pest Thoroughly inspect the premises to locate

harborage sites Encourage sanitary conditions Apply insecticides to targeted sites

Inspection tips:recognize common

signs Blood stains from crushed bugs Fecal spots Shed skins & eggshells Offensive, sweet, musty odor

Inspection tips:common harborage sites

Cracks and crevices Mattress, box springs, bed frame Window and door frames Baseboards Carpet tack boards Electrical boxes Wall hangings Drapery pleats Loosened wallpaper Ceiling moldings

Sanitation

Vacuum mattress and premises ** (dispose of vacuum bag) ** ??

Scrub mattress seams Dry clean or launder bedding and clothing in

hot water - Dry on high heat. Repair plaster cracks Glue loosened wallpaper Remove wild animal roosts and nests

Chemical control Hundreds of products ‘registered’ for use on bed bugs in US Formulations

196 pressurized liquids 90 ready-to-use solutions 53 emulsifiable concentrates 47 dusts

Chemicals 196 Permethrin 140 Pyrethrins 12 variations of ‘-thrins’

Insecticides

Residual insecticides Spot treat harborage sites Dust formulations useful for wall

voids and attics Use only an appropriately labeled

insecticide on mattresses No insecticides are labeled for use

on bedding or linens

Misconceptions

ForeignersPoorHomelessReportsType O blood, etc…

Bed Bug Emergency Response Plan (BBERP)