W7 - Insects, Lice, Pinworms (pt1 - mosquitoes and repellents/insecticides)

What are characteristics of mosquito bites?

• bites on exposed skin

• self-limiting

Risk factors w/ mosquito bites (modifiable)

1. motion and bright colors (have bad vision)

2. scents - lotions, perfume, etc (strong sense of smell)

Risk factors w/ mosquito bites (non-modifiable)

CO2 production; lactic acid production; body heat

What are the types of diseases spread by mosquitos?

1. Malaria

2. Yellow Fever

3. Dengue Fever

4. Japanese Encephalitis

How is malaria spread?

By the Anopheles species

• nighttime disease transmission

How is yellow fever and dengue fever spread?

Both by Aedes egypti species

• daytime transmission

How is Japanese Encephalitis spread?

Culex species

• nighttime transmission

What is the location/incidence of Malaria?

• widespread thru-out Asia, Africa, and S. America

• most common ID

What is the location/incidence of Yellow fever?

• only in Africa and S. America

• greater incidences in urban African areas

What is the location/incidence of Dengue Fever?

most dispersed

What is the location/incidence of Japanese Encephalitis?

• limited to SE Asia, Oceana, etc.

• common in rural enviro

Where do the mosquitos that spread yellow fever live?

rural and urban enviro (not deterred by humans or loud noises)

Signs of dengue fever are similar to what other disease state

Flu-like - can be fatal due to internal bleeding

Which of the diseases that can be spread by mosquitos the most uncommon infection in travelers?

Japanese encephalitis (but still possible)

What are the main tips to avoid getting bites (other than physical and chemical methods)?

1. avoid mosquitoes and their habitats

2. shoring up (?) in living accommodations

3. ensuring no standing water present

4. AC/screens

What are physical preventions against mosquitoes?

clothing, barriers, enviro cxl, etc

What are chemical preventions against moswuitoes?

insecticides and repellants

Pt counseling against mosquitoes

1. wear neutral/natural colored clothing

2. time of day for application of insect repellant and/or insecticides depends on species

   1. daytime vs nighttime transmission

3. location and duration of travel dictates preventative tx

MOA of insect repellents / insecticides

chemical barriers (prevent mosquito, flea, and tick bites)

Ideal agent characteristics of insect repellents / insecticides

• effective for 8 hrs or more

• no irritation, systemic toxicity

• resistance to rub-off

• water-resistant

• grease-less and odorless

T/F - Insecticides contain DEET as an active ingredient

F - certain repellants contain DEET, not insecticides

Which of the following are repellents?

1. DEET containing (N,N-Diethyl-3-Methylbenzamide)

2. Oil of Lemon Eucalyptus (PMD)

3. Permethrin

4. Picaridin/Icaridin

5. Oil of Citronella

DEET containing, oil of lemon eucalyptus (PMD), Picaridin/Icaridin, Oil of Citronella

Which of the following are insecticides?

1. DEET containing (N,N-Diethyl-3-Methylbenzamide)

2. Oil of Lemon Eucalyptus (PMD)

3. Permethrin

4. Picaridin/Icaridin

5. Oil of Citronella

Permethrin

Which insect repellants have the MOA of interference w/ insect chemoreceptors?

1. DEET containing (N,N-Diethyl-3-Methylbenzamide)

2. Oil of Lemon Eucalyptus (PMD)

3. Picaridin/Icaridin

4. Oil of Citronella

1. DEET containing

2. Picaridin/Icaridin

Which insect repellants have the MOA of act as a biopesticide repellent?

1. DEET containing (N,N-Diethyl-3-Methylbenzamide)

2. Oil of Lemon Eucalyptus (PMD)

3. Picaridin/Icaridin

4. Oil of Citronella

1. Oil of Lemon Eucalyptus (PMD)

2. Oil of Citronella

What is the MOA of Permethrin?

contact based synthetic insecticide → causes CNS toxicity → death of insect upon contact

Which of the repellents can cause skin irritation and rashes?

1. DEET containing (N,N-Diethyl-3-Methylbenzamide)

2. Oil of Lemon Eucalyptus (PMD)

3. Picaridin/Icaridin

4. Oil of Citronella

1. DEET containing (N,N-Diethyl-3-Methylbenzamide)

2. Picaridin/Icaridin

Which of the repellants DON’T have ADEs?

1. DEET containing (N,N-Diethyl-3-Methylbenzamide)

2. Oil of Lemon Eucalyptus (PMD)

3. Picaridin/Icaridin

4. Oil of Citronella

Oil of Lemon Eucalyptus (PMD)

ADEs for oil of citronella are?

1. SOB (burn candle)

2. chest/eye/nose irritation

3. predispose to lung cancer

Does Permetherin have more or less skin irritation in comparison w/ repellants?

skin irritation >>> repellants; rashes

Repellants that cause skin irritation include:

1. DEET containing (N,N-Diethyl-3-Methylbenzamide)

2. Oil of Lemon Eucalyptus (PMD)

3. Permethrin

4. Picaridin/Icaridin

5. Oil of Citronella

1. DEET containing (N,N-Diethyl-3-Methylbenzamide)

2. Picaridin/Icaridin

Which of the anti-insect products has the shortest efficacy?

oil of citronella

• most effective only in first 30 min

Which has an age restriction, repellants or insecticides?

DEET containing repellants (only for 2 months and above)

Advantages of DEET containing repellants

wide availability in conc between 5 - 100%

Adv to Picaridin/Icardidin

1. cosmetic adv

2. available in conc 5 - 10%

   1. limited [ ] vs DEET

Adv to Oil of lemon Eucalyptus (PMD)

1. fragrance more cosmetically pleasing

2. endorsed by CDC for protection against West Nile Virus

Adv to Oil of Citronella

high pt acceptance due to pleasing fragrance

Adv to Permethrin

1. odorless

2. long DOA (8 hrs or more)

3. available in conc 0.5%

4. very strong agent applied to clothes

Rank the repellent based on pt acceptance (mainly d/t smell of prdt)

citronella > lemon euc > picaridin/icaridin » DEET

Disadv to DEET containing repellants

aesthetically unpleasing (issue w/ pt adherence)

Do DEET containing repellants have different efficacy?

NO - different concentration have same efficacy

Is the protection provided by different NON-DEET containing repellents and insecticides similar to protection given by DEET containing?

Yes - EPA approved products are efficacious and safe when used as directed

DEET containing repellants have a duration of

20% DEET → 4HR

• higher conc → longer duration

Duration of 30% Oil of Lemon Euc

4HR (lemon)

Duration of 50% Oil of Lemon

6HR (lemon)

Duration of Oil of Citronella

<2HR per application

Duration of Permetherin

~3 to 4 washings or ~2 wks

What are the main adv of Permethrin over the other anti-insect products?

1. odorless

2. longest DOA

T/F - When comparing NON-DEET containing repellants and insecticides to DEET containing repellants, their duration of protection is different regardless of similar conc.

F - DOA of Non-DEET and DEET approx AT SIMILAR CONC

Which product is the primary alternative to DEET repellants?

Picaridin/Icaridin

What is the primary ingredient in Oil of Citronella?

Cymbopogon grass (lemongrass)

Patient Counseling Points for Repellants (DEET and non-DEET)

• do not apply to broken/irritated/damaged skin

• don’t let children apply repellents to themselves

• do ot spray directly onto face/body

• apply sunscreen first (30 min before repellants)

• reapply product when bites occur

• wash off repellants when not needed

How long does a pt need to wait before they can apply a repellant after applying sunscreen?

30 min

Should you instruct a pt to apply a repellant before or after sunscreen?

After

Pt Counseling Points for Insecticides

• apply liberally to clothing, shoes, tents, nets, etc

• never apply to skin

• does not stain clothing

• odorless

• maintain potency for ~2wks w/o washing

• potency retain thru 3-4 washing

Should a pt apply insecticides to their skin?

NO

Should miscellaneous insect repellants (bath oils, IR3535, Neem, Essential oils, Thiamine, garlic supplements) be recommended?

DO NOT recommend these products

Why are miscellaneous insect repellants (bath oils, IR3535, Neem, Essential oils, Thiamine, garlic supplements) not recommended?

lack of proven efficacy or insufficient duration of protection

Bath Oils are better physical or chemical barriers?

physical barrier

Products containing IR3535 (in Avon Skin-to-Soft) are not recommended d/t…

Short DOA (0.5 to 2HRS)

Neem (vege oil from A. indica seeds) is not recommended d/t…

ADRs of dermatitis, possible infertility

Essential oils are not recommended d/t…

1. effect variable

2. highly volatile

Thiamine and garlic supplements are not recommended d/t…

anecdotal evidence (no evidence to support use)