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Canada Communicable Disease Report
Volume 31 • ACS-4
15 May 2005
An Advisory Committee Statement
(ACS) Committee to Advise on Tropical
Medicine and Travel (CATMAT)*†
Statement on Personal Protective Measures
to Prevent Arthropod Bites
PDF
Version
20 Pages - 299 KB
Preamble
The Committee to Advise on Tropical Medicine and
Travel (CATMAT) provides the Public Health Agency of
Canada (PHAC) with ongoing and timely medical,
scientific, and public health advice relating to
tropical infectious disease and health risks
associated with international travel. PHAC
acknowledges that the advice and recommendations set
out in this statement are based upon the best current
available scientific knowledge and medical practices,
and is disseminating this document for information
purposes to both travellers and the medical community
caring for travellers.
Persons administering or using drugs, vaccines, or
other products should also be aware of the contents
of the product monograph(s) or other similarly
approved standards or instructions for use.
Recommendations for use and other information set out
herein may differ from that set out in the product
monograph(s) or other similarly approved standards or
instructions for use by the licensed manufacturer(s).
Manufacturers have sought approval and provided
evidence as to the safety and efficacy of their
products only when used in accordance with the
product monographs or other similarly approved
standards or instructions for use.
Introduction
There are blood feeding arthropods (insects and
arachnids) that carry and transmit various pathogens,
leading to diseases known as "arthropod-borne
diseases" (ABDs). Usually, these pathogens complete a
portion of their lifecycle within the arthropod
vector before they can infect humans and are
transmitted through the bite of the arthropod.
Exceptions, however, include Chagas disease and
louse-borne typhus, transmitted through feces
defecated on the skin by the arthropod during
feeding. Mosquitoes are considered to be the most
important vector for ABDs (e.g. malaria and dengue),
but many other types of arthropods transmit
disease-causing pathogens(1). Table 1
summarizes the information on the important arthropod
vectors.
Unfortunately, there are preventive vaccines,
chemoprophylactic drugs, or specific therapy for only
a minority of ABDs. Even if vaccines or drugs are
available, they are not totally effective, making
measures to minimize insect bites an important way -
and for some ABDs the only way - to reduce the risk
to the traveller of acquiring ABDs . Many factors -
such as the season, the time of day, and the
preference for indoor or outdoor feeding - influence
the feeding habits of arthropods(1)
(Table 1). Although knowledge of
arthropod feeding habits would allow the traveller to
significantly reduce ABD risk (e.g. when to stay
indoors, when to apply repellent), arthropod
behaviour is unpredictable. Reducing the risk for one
ABD likely decreases the risk for others, because
peak seasonality for transmitting ABDs in various
geographic regions overlaps.
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Table 2. Evidence-based
medicine (EBM) recommendations
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Recommendation
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EBM Rating
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Measures for all travellers who are at
risk of exposure to arthropod-borne infections
- Minimize entry of arthropods into work and
accommodation areas, including placing screens
on windows, and check to ensure that doors are
in good repair and close properly and tightly
and that the walls and the roof are "without
holes".
- Stay in an arthropod-protected area during
the time(s) of day when local arthropods are
actively biting.
- Avoid travelling to a locale during the
season that is most strongly (or only)
associated with transmission of arthropod-borne
infections.
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C III
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Physical barriers for all travellers who
are at risk of exposure to arthropod-borne
infections
- Wear long-sleeved shirts (sleeves down,
buttoned or zipped, tucked into pants) and long
pants (tucked into socks or footwear) to
inhibit or prevent arthropod bites.
- Dress in light-coloured clothing, which may
ward off some arthropods and allow people to
notice and remove certain arthropods, such as
ticks(2,3).
- Sleep under a mosquito net that is intact
(without tears or large holes), tucked in under
a mattress. Note that arthropods may still bite
through the mesh (if the traveller's skin is
against the net), or if the arthropod is
smaller than the mesh size, it can pass through
the netting.
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B II
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All travellers at risk of exposure to
serious arthropod-borne infections should
appropriately use insect repellent containing
DEET(6,7)-the preferred insect
repellent, unless contraindicated (e.g.
allergic reaction).
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A I
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For children, there are alternative
personal protective measures:
- Use insecticide-impregnated mosquito nets
as the first line of defense, especially for
infants aged < 6 months.
- Utilize portable mosquito nets, including
the self-standing type, placed over a car seat,
a crib, playpen, or stroller, providing an
insect-protected environment for infants.
- Consider the judicious use of DEET for
children of any age as a complement to the
other methods of protection(11).
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A II
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Extended duration (ED) DEET formulations have
useful advantages over other formulations and,
overall, are preferred(15-17). Where
ED formulations are unavailable, products that
contain up to 35% DEET are preferred.
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B I
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DEET and sunscreen combination products are not
generally recommended(18); however,
if DEET and sunscreen application are both
required, apply the sunscreen first, allowing
skin penetration for 20 minutes, followed by
DEET application (Canadian Dermatology
Association).
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A II
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Avoid using repellents containing citronella
oil(7,19).
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E II
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Consider P-menthane-3,8-diol (lemon
eucalyptus oil) as a second-line alternative
repellent, where DEET use is not possible (e.g.
persons allergic to DEET)(20).
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A II
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Consider soybean oil 2% "Blocker" repellents as
a third-line repellent, where arthropod-borne
infections present a significant
risk(7,23).
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A II
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Bayrepel (KBR 3023, Autan), available in
Europe(24), recommended by the World
Health Organization(27) and registered
with the Environmental Protection Agency (U.S.),
may be as effective as 15% to 50%
DEET(25,26). Repellents containing
Bayrepel are not registered for use in Canada.
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A II
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For all travellers who are at risk of
exposure to arthropod-borne infections:
- Sleep under insecticide
(pyrethroid)-impregnated mosquito nets (in
areas where insects cannot be excluded from
sleeping area)(4,5,14).
- Consider wearing insecticide
(permethrin)-impregnated
clothing(28,29).
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A I
AII
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Ineffective insect personal protection measures
that are not recommended:
- Electronic (ultrasonic)
devices(32,33)
- Wristbands, neckbands, and ankle bands
impregnated with repellents(7,34)
- Electrocuting devices ("bug zappers")
(35,36)
- Odour-baited mosquito
traps(33,37)
- Citrosa plant (geranium
houseplant)(33,38,39)
- Orally administered vitamin
B1(40)
- Skin moisturizers that do not contain an
approved repellent active
ingredient(7)
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E II
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All travellers should take, as directed,
all prophylactic medications recommended for the
prevention of arthropod-borne illnesses (such as
malaria), regardless of personal protection
methods used.
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A I
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Three Measures Used to Avoid Arthropods
- Minimize arthropod entry into work and
accommodation areas. Place screens on windows and
ensure that doors are in good repair and close
properly and tightly, and check that walls and roof
are without holes (C III - EBM recommendations).
- Stay in an arthropod-protected area during the
time(s) of day when local arthropods are actively
biting (C III - EBM recommendations).
- Avoid travelling to certain locales during the
season when transmission of ABDs is most likely (C
III - EBM recommendations).
Bite Prevention at the Personal Level
If insects cannot bite, ABDs cannot be transmitted;
it follows that aiming to reduce the amount of
unprotected skin available to the arthropod is
important.
There are both physical and chemical barriers to
prevent bites:
Physical barriers
-
Clothing
- Wear long-sleeved shirts (sleeves down,
buttoned or zipped, tucked into pants) and long
pants (tucked into socks or footwear) (B II - EBM
recommendations).
- Wear light-coloured clothing, which wards off
some arthropods and allows people to notice and
remove certain arthropods such as
ticks(2,3) (B II - EBM recommendations).
-
Mosquito net
- Although sleeping under a mosquito net is
well established as a useful barrier against
arthropod bites, arthropods still bite through
the mesh if the traveller's skin is against the
net. Similarly, if the arthropod is smaller than
the mesh size, the arthropod can pass through the
netting (A I - EBM recommendations).
- Treat (impregnate) mosquito netting with
insecticide (e.g. permethrin), substantially
increasing the protection afforded by the
net(4,5) (A I - EBM recommendations).
Chemical Barriers
Two types of chemical barriers reduce the risk of
ABDs: repellents and insecticides. Repellents do not
kill arthropods; rather, they produce an effect that
causes the arthropod not to bite, whereas
insecticides act primarily by killing an arthropod
upon contact. These approaches are not mutually
exclusive, and some chemicals have both effects,
acting as a repellent and an insecticide.
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Repellents
There are several repellent active ingredients
available for use in Canada and an even larger
number available in other countries (Table 3). Repellents, available for
sale in most (if not all) western nations, have
been reviewed for effectiveness and safety on the
basis of national regulations (in Canada, by Health
Canada's Pest Management Regulatory Agency [PMRA]
and in the United States, by the Environmental
Protection Agency [EPA]). During testing, some
repellents have been more effective (e.g. longer
lasting repellency) than others against certain
arthropod species.
- DEET
Generally, the repellent DEET
(N,N-diethyl-3-methyl- benzamide, also known as
N,N-diethyl-m-toluamide) is acknowledged
as the most effective repellent and is currently
available on the Canadian market(6,7)
(A I - EBM recommendations). DEET has been used
as a repellent since 1954 by the U.S. military
and is estimated to be applied several hundred
million times yearly by North Americans alone.
Scientific reviews have concluded that, when used
as directed, DEET has an excellent safety
record(6-14) (A I - EBM
recommendations).
The higher the DEET concentration in the
repellent formulation, the longer the duration of
protection; however, this relation reaches a
plateau at about 30% to 35%(6). For a
given DEET concentration, DEET formulations that
are "extended duration" (ED), such as polymers,
are generally considered to provide longer
protection times and may be associated with less
DEET absorption(6,7,15-17). The ED
formulations are unavailable to the general
public in Canada, but they are available in the
U.S.
Regulatory agencies in western nations may differ
in the recommended maximum concentration and
application rates of DEET, especially for
children. Health Canada's PMRA allows
concentrations of up to 30% in Canada for persons
aged >= 12 years. Those who are younger can
use up to 10% DEET; for those aged 2 to 12 years,
up to three times daily; and for children aged 6
months to 2 years, no more than once daily. The
PMRA disallows the use of repellents containing
DEET on infants under age 6 months(6).
However, CATMAT believes that, for travel outside
of Canada where ABDs are endemic or epidemic and
where exposure is likely and the risk for ABDs
outweighs the risk of an adverse reaction to
DEET, the threshold for use of DEET should be
low. In fact, CATMAT recommends that travellers
use DEET concentrations of up to 35% for travel
outside of Canada.
For children, alternative personal protective
measures, such as insecticide-impregnated
mosquito nets, should be the first line of
defence, especially for infants under age 6
months. Portable mosquito nets, including
self-standing nets, placed over a car seat, a
crib, playpen, or stroller, provide an
insect-free environment for infants. However, as
a complement to the other protection methods, the
judicious use of DEET should be considered for
children of any age. Recent medical literature
from Canada suggests that DEET does not pose a
significant or substantial risk to infants and
children(11).
The reapplication intervals on the labels of DEET
formulations are a general guide only, because
there are many variables - for example, sweating
- that affect duration of repellency. As a
general rule, the reapplication interval is a
function of arthropod biting activity, so if
biting is noted before the interval on the label
has expired, then reapplication of DEET is
recommended. DEET ED formulations have useful
advantages over other formulations and, overall,
are preferred when ABD risk is
high(15-17) (A II - EBM
recommendations).
DEET and sunscreen combination products are not
generally recommended; DEET decreases the
efficacy of sunscreens by 34%(18).
Further, the recommendations for application of
DEET and sunscreen are opposite. Sunscreen should
be used liberally and often, whereas DEET should
be used sparingly and only as often as required.
However, if application of both is required, the
Canadian Dermatology Association recommends that
the sunscreen be applied first and allowed to
penetrate the skin for 20 minutes prior to
applying DEET (A II - EBM recommendations).
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- "Natural-based" repellents
Most repellents containing "naturally derived,"
or synthetic analogues of "naturally-derived,"
materials are not considered the preferred
products for protecting against arthropod
bites. Oil of citronella products, for example,
can repel mosquitoes, but the protection
duration is very short (generally < 1 hour
and often < 30 minutes)(7). In
fact, a recent analysis by Health Canada
concluded that there are insufficient data to
establish that the use of citronella repellents
on skin does not pose an unacceptable risk to
human health(19).
Citronella-containing repellents are therefore
not recommended (E II - EBM recommendations).
P-menthane-3,8-diol, a synthetic
analogue of a lemon eucalyptus plant extract,
is registered in Canada for use as an insect
repellent ("OFF! Botanicals Lotion Insect
Repellent 1")(20). However, the
period of protection afforded by this product
(< 2 hours) is less than that for all but
very low concentration (< 5%) DEET products.
Besides, it is not approved for use on children
< 3 years of age. Data indicate that it is
reasonably effective against mosquitoes that
carry malaria(21,22). Repellents
that contain P-menthane-3,8-diol may be
considered a second-line alternative repellent
where DEET use is not possible (e.g. persons
who are allergic to DEET) (A II - EBM
recommendations).
Soybean oil 2% "Blocker" products are
equivalent to 5% to 10% DEET in efficacy,
repelling mosquitoes for 1 to 4 hours and
blackflies for 5 to 10 hours(7,23).
Soybean oil has low toxicity, has no
age-associated use restrictions, and is
non-irritating. Consequently, it may also be
considered an alternative to DEET, albeit one
with a substantially shorter protection time
and without a long history of use. Importantly,
CATMAT is unaware of scientific studies in
which soybean repellents have been tested for
effectiveness against tropical malaria vectors
or for many other ABD vectors. Soybean
repellents therefore are considered, at best, a
third-line repellent where ABDs present a
significant risk (A II - EBM recommendations).
Although there are "Blocker" products
containing soybean oil registered and approved
for use in Canada (www.biteblocker.ca), they
are not widely available in retail outlets.
- Other synthetic repellents
Bayrepel, a piperidine derivative also known as
"KBR 3023" and marketed under the trade name
Autan, has been used in Europe for several
years(24). It has demonstrated
action against various mosquito species,
including those that carry the malaria
parasite, with durations of protection,
compared with 15% to 50% DEET(25,26)
(A II - EBM recommendations). Toxicological
analysis suggests no bioaccumulation, and rapid
renal excretion with no significant toxicities
was reported. Although recommended by the World
Health Organization(27) and
registered with the Environmental Protection
Agency (U.S.) in 2002, repellents containing
Bayrepel have not been registered in Canada and
are not available in the U.S.
(www.autan.co.uk/index.html).
-
Insecticides
- Treated Mosquito Nets
All travellers planning itineraries to foreign
destinations that are endemic or epidemic for
ABDs should be strongly encouraged to use
pyrethroid (e.g. permethrin, deltamethrin,
lambda-cyhalothrin, cyfluthrin,
alpha-cypermethrin) insecticide-impregnated
mosquito nets, unless their sleeping quarters
are well screened or otherwise protected from
mosquitoes(14) (A I - EBM
recommendations). Pyrethroids either kill
arthropods directly after they land on
impregnated netting or repel them. In either
case, the end result is protection against
arthropod bites and ABDs.
Pyrethroid-impregnated nets are significantly
more effective in preventing malaria than
untreated nets and are safe for children and
pregnant women(4,5) (A I - EBM
recommendations). Duration of efficacy of
pyrethroid-impregnated nets varies from several
to 12 months, depending on the product
used(4) (Table 4
and Appendix 1). While
pyrethroids are generally considered to be of
low mammalian toxicity, care should be taken
when impregnating the permethrin or an
equivalent product into the net (e.g. follow
the label instructions, use impervious gloves,
and allow the net to dry before use) (Appendix 1). Pyrethroid treatments
for bed nets are not registered by the PMRA for
use by the general public.
Insecticide-impregnated bed nets that are
represented and sold for use in Canada require
registration under the authority of the Pest
Control Products Act (PCPA). However, the
PMRA has an interim policy of not requiring the
registration of either permethrin- or
deltamethrin-impregnated bed nets if imported
into Canada for sale to Canadians for use
abroad.
- Treating clothing
Treating clothing with pyrethroid will also
reduce the risk of ABDs (Appendix
2). Pyrethroid clothing treatments are not
registered by the PMRA for use by the general
public, but several products are available in the
U.S. These products usually consist of 0.5%
permethin in an aerosol or pump spray. Generally,
clothing that is treated with the 0.5% permethrin
aerosol or pump spray is effective at preventing
arthropod bites for at least 2 weeks, assuming
regular laundering practices (e.g. six machine
washings)(28,29). More recently,
outdoor clothing that was pre-treated with
permethrin became available in the U.S. (e.g.
clothing available under the trademark "Buzz-Off
Insect Shield"). This pre-treated clothing is
advantageous in that it maintains protective
levels of permethrin through 25 or more machine
washings (i.e. frequent retreatment is not
required). Combining a long-acting DEET
formulation that is applied to exposed skin and
the pyrethroid-impregnated clothing enhances
protection against biting
arthropods(30,31) (A II - EBM
recommendations).
- Ineffective insect personal protection measures
There are additional products that are marketed
as safe and "natural" and with effective measures
to substantially reduce the risk of arthropod
bites. However, CATMAT assesses some products as
lacking in the sufficient scientific basis to
recommend or as having the sufficient scientific
basis to indicate the product's lack of
usefulness (E II - EBM recommendations). These
products include electronic (ultrasonic)
devices(32,33), wristbands, neckbands,
and ankle bands impregnated with repellents
(whether for animal or human
use)(7,34), electrocuting devices
(i.e. "bug zappers")(35,36),
odour-baited mosquito traps(33,37),
the Citrosa plant (i.e. geranium house-
plant)(33,38,39), oral vitamin
B1(40), and skin moisturizers that do
not contain an approved repellent active
ingredient(7).
Summary
Several personal protective measures exist to reduce
the risk of acquiring ABDs. In fact, there is no
single measure on which to rely that provides
substantial confidence in protection; hence, CATMAT
recommends and views as complementary the use of all
measures.
Expiration
This document is updated every 4 years or when new
information becomes available.
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- Sholdt LL, Schreck CE, Mwangelwa MI et al.
Evaluations of permethrin-impregnated clothing and
three topical repellent formulations of deet
against tsetse flies in Zambia. Med Vet Entomol
1989;3:153-58.
Appendix 1 - Treating Mosquito Nets
with Insecticides (Adapted from Path Canada)
Always use metric measurements: centimetre (cm),
metre (m), millimetre (mm), millilitre (mL), and
litre (L). Clean and dry all nets. Always wear
protective gloves when soaking a net in insecticide.
-
Calculate the area of the net, in square
metres.
Consider a conical net as a triangle and a
rectangular net as two rectangles.
How to measure a mosquito net:
- Conical net
Lay the net flat to:
-
- Measure the total distance around the
curved base of the net (m)
- Measure the height (m)
- Multiply base x height = area of net
- Rectangular net
Hang up the net to:
- Measure the area of the top = width x length
- Measure the area around the sides = height x
total distance around base of net
- Add the two measurements together to obtain the
total area of the net
-
Calculate the amount of water absorbed by the
net, in millilitres or litres.
Using a bucket and a measuring container, measure
two litres of water into the bucket. Soak the net
until it is totally wet. Carefully wring out the
net over the bucket. When the net has stopped
dripping, measure the water remaining in the
bucket.
For example:
- Original water in bucket (2 L) minus remaining
water in bucket (1.3 L) = water absorbed by the net
(0.7 L or 700 mL)
-
Calculate the amount of insecticide
required.
- Obtain the highest quality product, in
original packaging, specifically designed for use
on mosquito netting. Avoid using products that
have not undergone meticulous quality control.
Avoid using substitute products.
- Check the recommended dosage of insecticide.
Read the instructions on the bottle, or see
Appendix 1,
Table 1.
- Check the concentration of the insecticide.
This follows the name of the insecticide. For
example, permethrin EC 50 contains 500g of
insecticide in each litre; this is also known as
a 50% solution.
Table 1. Doses of commonly used
insecticides in mg per square metre of
material (polyester)
|
Compound and formulation
|
Dose (mg of active ingredient/ square
metre)
|
Permethrin EC
|
200-500
|
Deltamethrin SC
|
15-25
|
Deltamethrin tablet
|
1 tablet per net
|
Lambda-cyhalothrin CS
|
10-15
|
Cyfluthrin EW
|
30-50
|
Alpha-cypermethrin SC
|
20
|
To calculate the amount of insecticide use the
following formula:
- Dosage (mg/unit metre) x Area of Net (in square
metres) to determine the amount of insecticide
required in mg. (Note: there are 1,000 mg per gram,
1,000 mL/L, and 1 gm per mL.)
- Take amount of insecticide required divided
by the amount in mg of insecticide per mL of
product (for example, a product that contains 50%
permethrin will contain 500 g permethrin/L and
therefore 500 mg permethrin/mL) = amount of
insecticide required in mL.
For example:
If you want a dosage of 200 mg/square metre on an
11 square metre net, using a product containing 50%
permethrin w/w, calculate the amount required as
follows:
- 200 mg/square metre x 11 metres squared = 2,200
mg permethrin required
- 50% permethrin = 500 mg permethrin/mL
- 2,200 mg divided by 500 mg/mL = 4.4 mL
insecticide required to treat the net
If the net absorbs 0.7 L (700 mL) of water, add
this amount of water to the insecticide to make a
final mixture.
-
Wear protective gloves when treating nets with
insecticide.
-
Measure the amount of water and insecticide
needed.
Wide-mouth containers, such as an empty margarine
container (1 kg = approximately 1 L), are best for
measuring large amounts of water. Measure
insecticide using a 250 mL empty container that can
be scored inside at 50 mL intervals. For small
amounts of insecticide, use a syringe.
-
Add the insecticide to the water and mix
well.
Perform treatment outdoors or in a well-ventilated
area. Alternatively, you can place the net in a
plastic bag (ensuring that the bag contains no
holes), then, add the insecticide and water
solution, knead well, and remove the treated net
from the bag for drying.
-
Dip the net in the solution until it is
thoroughly wet.
-
Wring out the net over a bowl and hang up
until it has stopped dripping.
-
Dry the net.
Wet nets can be laid out flat to dry. Avoid placing
the net in direct sunlight for more than a few
hours, because UV exposure may reduce the efficacy
of the insecticide.
-
Wash your hands and all equipment with soap and
water.
Triple rinse any containers for reuse, and punch
holes in containers or equipment that will be
discarded to prevent their reuse as drinking water
containers.
-
Pour any waste insecticide down a pit latrine or
into a pit dug into the ground, and NOT into a
river or pond, because pyrethroids are highly toxic
to fish and aquatic invertebrates.
Note: Prior to travelling, inquire about the
availability of insecticide, and plan to purchase and
apply these products at your destination.
Pre-impregnated mosquito nets are available from PATH
Canada on its Web site at http://www.pathcanada.org
and are found in some travel and mountain equipment
stores in Canada and in the U.S. These products are
not currently registered by the PMRA.
For information regarding availability of
insecticides in sub-Saharan Africa for application
onto clothing or nets, visit the PATH Canada Web site
at http://www.pathcanada.org.
Appendix 2 - How to Treat Clothing
with Insecticides (Adapted from Sawyer Products)
-
Select an area that is well ventilated, but out
of the wind. Avoid spraying in an enclosed area.
-
Lay the clothing flat on the ground, pin the
clothes on a clothesline, or drape over porch
furniture and railings or on separate clothes
hangers, so each garment can be easily sprayed
and allowed to thoroughly dry.
-
One treatment with permethrin spray will remain
effective for 2 weeks, including weekly
launderings. A treatment of 100 mL (3 ounces) of
permethrin spray will cover one complete set of
garments (a pair of long-legged trousers and a
long-sleeved shirt). Treat jackets, windbreakers,
and rain gear in the same manner. (Caution:
permethrin does not adhere well to some synthetic
fibres.)
-
Wear protective gloves.
-
Spray one side of the garment for approximately
60 seconds, holding the spray can or bottle
upright and 15 cm to 20 cm away from the surface.
Spray in a slow sweeping motion, similar to
spraying paint, to evenly coat the entire
surface. Turn the garment around to the other
side, and repeat by spraying the second side for
60 seconds. Wet surface of clothing, but avoid
completely saturating with spray.
-
Hang up garments, and allow the permethrin
treatment to dry for 2 hours, or 4 hours if
conditions are very humid.
- Treat other garments and gear (do not treat
underwear):
- Treat socks with permethrin spray. Lay socks
on the ground, or pin on a clothesline, and
lightly spray the upper part. Allow to dry for 2
or more hours.
- Treat polyurethane-coated nylon (synthetic)
tent flaps and doors with permethrin spray. Erect
tent outdoors, and spray all tent flaps and doors
until wet. Leave standing for 2 or more hours to
dry.
- After garments have dried, pack them as you
normally would for your trip. You may also want to
roll up your treated clothes and store them in a
plastic bag to keep them dry. Pack tents as you
normally would.
Note: Prior to travelling, inquire about the
availability of insecticide, and plan to purchase and
apply these products at your destination. These
products are not currently registered by the PMRA.
For more information regarding application of
insecticides onto clothing, please visit the
permethrin Web site at
http://www.permethrin-repellent.com.
|