Transcript Cockroaches in General

Cockroaches, Beetles, and other
Nuisance orders
Announcements
Presentation Schedule
Reading: Chap 7
A Key Concept in DV Management is
Risk
• Most DV Management is Govt. Funded
• They fund efforts in response to perceived risk
• Risk = Cost of a Bad Outcome
TIMES
Probability of that Outcome
Occurring
The main problem is there are multiple
risks
• Multiple “Bad Outcomes” including
– Economic
– Environmental
– Social
– Political
• Each outcome has it’s own cost and
probability
• Major Complication: Disease risk is inversely
correlated with vector control.
Nuisance Species – Species which lack
a direct or vectored
medical/veterinary impact
• Temporary (e.g. overwintering) invaders. E.g.
crickets, lady beetles.
• Permanent, non-medical/veterinary
inhabitants. E.g. booklice, fungus gnats, etc.
• Permanent inhabitants with
medical/veterinary significance
– Indirect issues – the subject of this lecture
Nuisance species generally cause these
types of problems
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•
•
•
•
•
•
Some food-borne disease
Other surface contamination disease
Intermediate/secondary hosts
Allergies & Asthmatic Reactions
Psychiatric/psychological disorders
Social stigma
Degrades quality of life (they’re disgusting)
Cockroaches in General
• Cockroaches the most common insect pests
infesting homes, food service establishments
and other structures in in the US.
• There are over 4,000 species of cockroaches in
the world and numerous species can become
pests in the US.
• Generally, the further south one goes, the
more pest species there are with which to deal.
Cockroach Infestation
Cockroach Infestation
Cockroach Infestation
Cockroach Infestation
Cockroach Infestation
Cockroach Infestation
Main Problem of Cockroaches –
Allergy X Asthma Interaction
• Allergy -- a hypersensitive state acquired through exposure to a particular
allergen, reexposure bringing to light an altered capacity to react. Most
common type with cockroaches is “Atopic”
• Asthma - a chronic (long-lasting) inflammatory disease of the airways. 90%
of cases are “Extrinsic”
• Interaction between the two is usually expressed as Bronchial
Hyperresponsivness (BHR). BHR is an exaggerated bronchial constriction in
response to specific or nonspecific provocation.
Constriction of Bronchial Muscles
Inflammation of Bronchial Wall
Cockroach-mediated BHR (CM-BHR)
• A combination of social, genetic, and cockroach-specific
factors.
• Increasing in North American & European inner cities at about
75%/10 years - the problem is growing.
• Incidence increases as one moves up the NIH Asthma severity
scale:
– Mild Intermittent Asthma: Pulmonary function >= 80% of normal ;
Episodes infrequent. CM-BHR Incidence < 20%
– Mild Persistent Asthma: Pulmonary function >= 80% of normal;
Episodes > 2/week but < 1/day; Normal activity affected. CM-BHR <
20 – 40%
– Moderate Persistent Asthma: Pulmonary function >= 60% but < 80%
of normal. Episodes frequent. Daily use of inhaler. Activity
significantly affected. CM-BHR Incidence 40 -80%
– Severe Persistent Asthma: Pulmonary function <= 60%. Episodes
continuous & limited physical activity. CM-BHR > 80%
CM-BHR Epidemiology – Likelihood that a child will have CM-BHR
in S. New England, 2006
Cockroaches in Kentucky
• In Kentucky, we are primarily concerned with four
species:
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German cockroach, Blatella germanica L.,
brownbanded cockroach, Supella longipalpa F.,
oriental cockroach, Blatella orientalis L.,
American cockroach, Periplaneta americana L.
• Of these, the one that has is most troublesome is
the German cockroach, which prefers indoor
locations.
• Oriental and American cockroaches occasionally
pose problems in moist, humid areas.
Kentucky Cockroaches -- Adults
Basic Life Cycle
• Incomplete
Metamorphosis
• Eggs deposited in
“packs” called oothecae
• 3 – 5 nymphal instars
• Total lifespan in a
dwelling – 8 – 12 weeks
• Most temperate pest
species lack overwintering
stage.
Life Stages of the German
Cockroach
Kentucky Cockroaches – Oothecae
Cockroach Control
• See your text on pp. 55
• Gel Baits are the most
effective controls at
present
• Many are general use
Baits are typically used with traps
A single bait treatment can be highly effective in
reducing cockroaches
From: Sever et al. 2007
Cockroaches/trap
500
400
300
Control
Bait
200
100
0
0
1
3
6
9
Months Post Treatment
12
More Importantly, Chemical Baits
Alone Can Reduce Allergens (ibid)
Biocontrol continues to draw interest –
Interesting Aside: The Jewel Wasp
• Stings roach in the brain. Venom paralyzes the part
of brain that controls free will. Zombie roach with
follow the wasp anywhere.
• National Geographic article, 2007
• YouTube Video
Beetles
• Chapter 8 in your text.
• Largest order of insects: 350,000 spp or about
40% of all insect spp. This is really the only
reason that we mention them in this class.
• Most are either phytophagous or predatory.
Minor significance to human and animal
health.
Beetles
• Most problems in our area are either as nuisance
species (lady beetles) or veterinary problems
(ingestion of toxic beetles).
• Intermediate hosts of many veterinary pathogens
(see text)
• Some have medically-important benefits
– Forensic entomology
– Some medicinal products
– Some interrupt disease transmission in mammals (e.g.
dung beetles).
Beetle Morphology
• Distinctive wing
arrangement
• Holometabolous
• Abdomen broadly
joined to the
pterothorax
Blister beetles
• Most common toxic
beetle in Kentucky
• Striped blister beetle is
the most common
species
• Often occur in swarms
or clusters.
Blister Beetles
• All possess a terpenoid,
cantharidin, which causes
blisters
• Human LD50 is 0.5 mg/kg, 10
mg could be fatal.
• Cantharidin is carried in the
beetle’s blood.
• In all life stages
• Available commercially as a
wart treatment.