Note: Descriptions are shown in the official language in which they were submitted.
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ECTOPARASITE ERADICATION METHOD AND DEVICE
FIELD OF THE INVENTION
The present invention relates generally to the elimination of ectoparasites.
More particularly, the present invention relates to utilizing heated forced
air to
eliminate ectoparasites.
BACKGROUND OF THE INVENTION
Over the past decade, cases of head lice have been increasing rapidly
throughout the world, with an estimated ten million cases per year in the U.S.
alone. Head lice, Pediculus capitis, are a major irritant to children and
their
parents. P. capitis have three life stages, including an egg stage, three
juvenile
instars, and an adult stage. Head lice infestations cause children to miss an
estimated 12-24 million days of school per year. Ridding a person of head lice
is
an extremely difficult and frustrating task. Indeed, some families,
particularly in
developing countries, have chronic infestations that are never eradicated.
Head
lice and body lice, P. humanus, are extremely similar genetically, and recent
research suggests that they may be members of the same species. The
similarity of head lice to body lice is cause for concern because body lice
vector
several human diseases, including epidemic typhus and relapsing fever,
diseases
that killed many millions of people during the 20th century.
Several methods of treatment for head lice infestations are currently
available, including pesticidal shampoos, specialized louse combs and home
remedies. Many of these treatments may be inefficient in eliminating head lice
infestations. For example, specialized shampoos have never been shown to
effectively kill eggs, and hatched lice have begun to evolve resistance to
most of
them. The use of a louse comb to comb the hatched lice and eggs out of an
individuals hair can be effective, but is very time intensive and tedious to
use.
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2
Most parents do not have the patience to eliminate the infestation in this
manner.
Additionally, hot air treatments have been suggested as a possible treatment
for
lice. However, though hot air has been shown to kill lice and their eggs in
vitro,
such treatments are generally ineffective in vivo.
A method of eradicating head lice infestations is needed that effectively
kills both hatched lice and their eggs, but is safe, reliable, and easy to
use.
Additionally, it would be desirable that such a method utilize non-chemical
means
to prevent the lice from developing resistances to the treatment and avoid any
undesirable side effects to the patient.
SUMMARY OF THE INVENTION
It has been recognized that it would be advantageous to develop a
reliable, non-chemical treatment for eradicating head lice and other
ectoparasites. A method of eliminating an ectoparasite infestation is
disclosed
that may include steps of defining a target area on an animal having an
ectoparasite infestation, heating a volume of air to a temperature to form
heated
air, applying the heated air to the target area with an airflow such that the
heated
air impinges directly on substantially all ectoparasites located within the
target
area, and maintaining the heated air at the target area for a period of time
sufficient to affect an ectoparasite mortality rate of at least 50%.
In another embodiment of the present invention, an institutional method for
eliminating an ectoparasite infestation is disclosed. The method may include
steps of defining a target area on a human having an ectoparasite infestation,
heating a volume of air to a temperature of from about 50 C to about 100 C
to
form heated air, applying the heated air to the target area with an airflow of
from
about 45 ft3/min to about 365 ft3/min, such that the heated air impinges
directly on
substantially all ectoparasites located within the target area, and
maintaining the
heated air at the target area for from about 5 seconds to about 1 hour.
The present invention may include methods to increase the impingement
of the heated air on the ectoparasites located within the target area. In one
aspect, a method may include steps of determining that the human having an
ectoparasite infestation has a hair length suitable for sectioning, dividing
the hair
into a number of discrete sections to expose a plurality of scalp areas, and
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3
sequentially applying the heated air to each discrete section of hair
associated with
each of the plurality of scalp areas. In another aspect, a method may include
a step
of systematically applying heated air to the target area utilizing a comb
device to
separate and lift hair within the target area.
In yet another embodiment of the present invention, a handheld method
for eliminating an ectoparasite infestation is disclosed. The method may
include
steps of defining a target area on a human having an ectoparasite infestation,
heating
a volume of air to a temperature of from about 50 C to about 100 C to form
heated
air, applying the heated air to the target area with an airflow of from about
20 ft3/min
to about 220 ft3/min such that the heated air impinges directly on
substantially all
ectoparasites located within the target area, and maintaining the heated air
at the
target area for a period of time sufficient to affect an ectoparasite
mortality rate of at
least 50%.
Specific aspects of the invention include:
use of a device for the elimination of an ectoparasite infestation on an
animal, the device comprising: a chamber for heating a volume of air to a
temperature to form heated air; and a conduit for applying the heated air to a
target
area defined on the animal with an airflow, such that the heated air is
applied directly
to and directly contacts a scalp of the animal and such that the heated air
impinges
directly on substantially all ectoparasites located within the target area;
use of an institutional device for the elimination of an ectoparasite
infestation on a human, the institutional device comprising: a chamber for
heating a
volume of air to a temperature of from about 50 C to about 100 C to form
heated
air; and a conduit for applying the heated air to a target area with an
airflow of from
about 45 ft3/min to about 365 ft3/min, such that the heated air impinges
directly on the
human's scalp, and such that the heated air impinges directly on substantially
all
ectoparasites located within the target area; and
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use of a handheld device for eliminating an ectoparasite infestation on a
human, the handheld device comprising: a chamber for heating a volume of air
to a
temperature of from about 50 C to about 100 C to form heated air; and a
conduit for
applying the heated air to a target area with an airflow of from about 20
ft3/min to
about 220 ft3/min, such that the heated air is applied directly to and
directly contacts
the human's scalp, and such that the heated air impinges directly on
substantially all
ectoparasites located within the target area.
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Additional features and advantages of the Invention will be apparent from
15 the detailed description which follows, taken in conjunction with the
accompanying drawings, which together illustrate, by way of example, features
of
the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
20 FIG. 1 Is a flow chart of a method of eliminating head lice in
accordance
with an embodiment of the present invention;
FIG. 2 Is a flow chart of a method of eliminating head lice in accordance
with an embodiment of the present invention;
FIG. 3 is a flow chart of a method of eliminating head lice in accordance
25 with an embodiment of the present invention;
FIG. 4 is a flow chart of a method of eliminating head lice in accordance
with an embodiment of the present invention;
FIG. 5 is a perspective view of a comb device for lifting and separating
hair; and
30 FIG. 6 is a flow chart of a method of eliminating head lice in
accordance
with an embodiment of the present invention.
DETAILED DESCRIPTION
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In the previously filed U.S. Patent Application (Publication No. US
2005/0261740), airflow
ranges were presented that were obtained using a pliot tube anemometer, as is
common in the art. Further testing has indicated, however, that such
measurements may be in error, and are thus inaccurate. Interestingly, reported
measurements for airflow from various manufacturers of blow dryers vary
widely,
as is discussed in the examples below. These reported measurements appear to
be mere marketing tools for blow dryer manufactures. As such, this
continuation-
in-part has been filed to correct the inaccurate airflow range values reported
in
the above referenced parent application. The following airflow ranges are
intended to be volumetric measurements, examples of which are described in the
Examples section below. The high and the low endpoints to the airflow ranges
have been shifted downward to accommodate the newly measured airflow a
values, but the size of each range has been maintained for consistency. It
should
be noted that the previously reported inaccurate airflow range values were
merely
innocent errors based on what was believed to be standard measurement
practices in the art. Reliance on these flawed standard measurement practices
resulted in the inaccurate airflow range values. As such, the airflow ranges
have
been modified but the novel aspects of the present invention are unchanged.
Reference will now be made to the exemplary embodiments illustrated in
the drawings, and specific language will be used herein to describe the same.
It
will nevertheless be understood that no limitation of the scope of the
invention is
thereby intended. Alterations and further modifications of the inventive
features
illustrated herein, and additional applications of the principles of the
inventions as
illustrated herein, which would occur to one skilled in the relevant art and
having
possession of this disclosure, are to be considered within the scope of the
invention.
Though the following discussion is focused primarily on head lice, it should
be noted that numerous species of ectoparasites can be killed by utilizing the
disclosed invention. As such, the present invention is not limited to head
lice, but
extends to the various species of ectoparasites that may be affected by the
methods disclosed herein. Examples may include various species of lice,
including head and body lice, as well as, without limitation, ticks, fleas,
crab lice,
mites, parasitic flies, etc.
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The inventors have discovered a very effective method for killing head lice
and their eggs. They have found that heated air delivered at high volumes
increases the mortality rate of lice eggs and hatched lice. This discovery has
the
added advantages of eradicating or eliminating ectoparasite infestations with
5 greater levels of safety, efficacy, speed, simplicity, and cost-
effectiveness than is
previously known in the art. In their in vivo studies, a significant number of
hatched head lice survived after being exposed to air from a bonnet style hair
dryer at 60 C. Similar results were obtained from tests utilizing a standard
consumer hand-held blow dryer. Nearly all lice exposed to heated air at 59 C
with an airflow of at least 85 ft3/min, however, died within 20 seconds when
the
heated air impinged directly on the lice. The significant survival rate in the
first
experiments may be due to the lower airflow associated with the bonnet style
hair
dryer and the hand-held blow dryer, as well as the inefficient manner in which
these devices deliver heated air to those locations harboring lice and their
eggs.
This inefficient heated air delivery may allow lice to escape into cooler air
pockets
within clumps of hair matted down by the hair dryers. The inventors believe
that
the significantly higher mortality rate in the second experiment may be due to
a
combination of heated air, the high airflow rate, and the manner in which it
was
applied. Heated air applied in such a manner is a preferred method for
treating
head lice because it is non-chemical, it requires comparatively less time than
shampoos or combing, and it is a method of treatment to which lice may not
evolve resistance. These methods thus have the potential to become a
permanent cure for head lice, worldwide.
An animal infested with an ectoparasite will generally require treatment to
most if not all of the surface area of the infested region. The nature and the
location of the infestation may vary greatly depending on the animal and the
particular species of ectoparasite involved. For example, infested regions on
a
human having head lice will differ from infested regions on a dog having
fleas.
Given the wide variety of animals susceptible to numerous types of
ectoparasitic
infestations, methods of defining and treating a target area can vary
dramatically.
Thus the methods as described herein are merely exemplary, and are not
intended to be limiting in any way.
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Similarly, it is intended that all animals that experience ectoparasitic
infestations and can derive benefit from these methods be included in the
present
scope. This may include, for example, reptiles, mammals, birds, etc.
Additionally, in one embodiment of the present invention the animal is a
mammal.
In another embodiment, the animal is a human. In order to simplify the
explanation of the present invention, and without intending to be limiting,
the
following discussion will be primarily directed to a human host having a head
lice
infestation.
FIGS. 1-4 and 6 schematically depict possible steps for method
embodiments of the present invention. Not every step depicted is necessarily
performed for a given embodiment. Similarly, the order of the steps as shown
is
not intended to be limiting, and it is to be understood that variations in
order are
considered to be within the scope of the present invention.
As shown in FIG. 1, the present invention may be embodied as a method
10 for eliminating an ectoparasite infestation. The method may comprise steps
of
defining a target area on an animal having an ectoparasite infestation 12,
heating
a volume of air to a temperature to form heated air 14, applying the heated
air to
the target area with an airflow, such that the heated air impinges directly on
substantially all ectoparasites located within the target area 16, and
maintaining
the heated air at the target area for a period of time sufficient to affect an
ectoparasite mortality rate of at least 50% 18. Although the 50% mortality
rate
may be acceptable in marginal circumstances, the present invention has also
demonstrated an effective mortality rate of about 100%, which is obviously
preferable. In contrast, prior art techniques have not been capable of
realizing an
effective 50% mortality rate in situ.
Defining a target area on an animal having an ectoparasite infestation 12
may result in multiple discrete target areas, or it may result in a target
area
encompassing the entire infested region. Well defined target areas may
facilitate
the systematic application of the heated air to all infested regions of the
animal,
and thus help to ensure treatment of the entire animal through treatment of
multiple discrete regions. In other cases, the application of the heated air
may
occur over broad areas of the animal or multiple areas simultaneously.
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Heating a volume of air to a temperature to form heated air 14 may be
accomplished by any means known to one skilled in the art, as long as
sufficient
heat can be maintained in an airflow of heated air to allow the eradication of
head
lice. Any temperature of heated air that is effective at eliminating head lice
is
considered to be within the scope of the present invention. In one embodiment,
the temperature of the volume of air is at least 50 C. An upper limit for
temperature may be dependent on the heat endurance of the infested animal.
Also, pain and discomfort thresholds are highly variable among individual
humans, and thus the maximum useful temperature would be similarly variable.
It is also recognized that maximum useful temperature may be different for
nonhuman animals. The heat endurance of the animal may also vary with the
duration of application, as higher temperatures may be tolerated for shorter
periods of time than what would be typically used for lower temperatures. In
one
embodiment, the temperature of the volume of air can be from about 50 C to
about 100 C. In another embodiment, the temperature of the volume of air can
be from about 54 C to about 65 C. In another embodiment, the temperature of
the volume of air can be from about 54 C to about 59 C. In yet another
embodiment, the temperature of the volume of air can be about 59 C.
The heated air may be applied to the target area 16 by any means known
to one skilled in the arts, as long as the airflow of heated air can be
maintained at
a sufficient rate to allow the eradication of head lice. Any airflow that is
effective
at eliminating head lice is considered to be within the scope of the present
invention. As with the application of heat, an upper limit to airflow may be
dependent on the endurance of the infested animal. Airflow that can be
tolerated
by an animal will vary depending on the species. For example, pachyderms may
tolerate very high airflow as compared to humans or birds. In one embodiment
of the present invention, the airflow is from about 25 ft3/min to about 2000
ft3/min.
In another embodiment, the airflow is from about 30 ft3/min to about 430
ft3/min.
In yet another embodiment, the airflow is from about 35 ft3/min to about 285
ft3/min.
The heated air can also be applied to the target area by systematically
applying the heated air to the target area utilizing a device to separate and
lift
hair. This device can be any means known to one skilled in the art that can
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separate and lift hair while applying heated air to ensure that substantially
all
regions of the target area have been thoroughly heated. In one aspect, the
device can be a comb device. The comb device can be attached to the device
delivering the heated air or it can be separate. The inventors have found that
utilizing such a comb device can increase the effectiveness of the treatment
regardless of the length of the hair. One example of the comb device is
described below in more detail.
In one embodiment of the present invention, the heated air may be
maintained at the target area for a period of time sufficient to affect an
ectoparasite mortality rate of at least 50% 18. It is intended that the period
of
time include continuous and discontinuous periods. For example, heated air can
be maintained continuously at the target area until at least 50% mortality
rate has
been achieved. In another example, heated air can be delivered to the target
area in multiple applications, such that the combined effect of the multiple
applications achieves a mortality rate of at least 50%. The intervening time
period between applications can be seconds, minutes, hours, days, weeks, etc.
Though mortality rates of at least 50% are disclosed, the inventors have
discovered that proper application of the methods disclosed herein will result
in
the complete elimination of ectoparasitic infestations, particularly those
involving
head lice. Specific embodiments do, however, contemplate lower mortality
rates.
In these cases, it may be acceptable to obtain these lower mortality rates
while
treating the infested individual multiple times, as described above. For
example,
in an embodiment where a treatment results in a 50% mortality rate, repeating
the procedure for multiple days may produce acceptable results. As such, in
one
embodiment the heated air is maintained at the target area for a period of
time
sufficient to affect an ectoparasite mortality rate of at least 70%. In
another
embodiment the heated air is maintained at the target area for a period of
time
sufficient to affect an ectoparasite mortality rate of at least 85%. In yet
another
embodiment the heated air is maintained at the target area for a period of
time
sufficient to affect an ectoparasite mortality rate of at least 95%.
The time period that heated air may be maintained to provide an
acceptable ectoparasite mortality rate can be highly variable depending on
several factors, including temperature, airflow, coarseness and length of
hair, the
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type of ectoparasite, and how directly the heated air impinges on
ectoparasites
within the target area. It is well within the ability of one of ordinary skill
in the art
to evaluate the circumstances of a particular infestation and to time the
application of the heated air accordingly. In those cases where the target
area
One skilled in the art in possession of these methods would appreciate
that no single factor recited above would allow the total elimination of a
head lice
As shown in FIG. 2, one embodiment of the present invention provides for
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That being said, the method can Comprise steps of defining a target area on a
human having an ectoparasite infestation 22, heating a volume of air to a
temperature of from about 50 C to about 100 C to form heated air 24,
applying
the heated air to the target area with an airflow of from about 46 fta/min to
about
5 365 ft3/min or from about 170 ft3/rnin to about 490 ft3/min 26, such that
the heated air impinges
directly on substantially all ectoparasites located within the target area,
and maintaining the
heated air at the target area for from about 5 seconds to about 1 hour 28.
As described above, defining a target area on a human having an
ectoparasite infestation 22 may result in multiple discrete target areas, or
it may
10 result in a target area encompassing the entire infested region. Well
defined
target areas may facilitate the systematic application of the heated air to
ail
infested regions of the human, and thus help to ensure treatment of the entire
infested region of the human through treatment of multiple discrete regions.
In
other cases, the application of the heated air may occur over broad areas of
the
human, or multiple areas simultaneously.
One particular advantage to treating an ectoparasite infestation in an
institutional setting is the performance of the treatment by an experienced
clinician. The inventors have discovered that mortality rates of ectoparasites
tend
to increase with the experience of the individual performing the treatment.
One
explanation for this may be that the experienced clinician is better able to
ensure
that the entire infested area is thoroughly treated. If a region is missed
during a
treatment, ectoparasites from that region will spread, causing a rapid
reinfestation.
Heating a volume of air to a temperature of from about 50 C to about 100
C to form heated air 24 may be accomplished by any means known to one skilled
in the art, as long as sufficient heat can be maintained in an airflow of
heated air
to allow the eradication of head lice. Care may be taken to minimize the
discomfort of the human receiving the treatment due to the temperature of the
heated air. The maximum temperature that may be used is likely to be
dependent on the heat endurance of the infested human. Also, pain and
discomfort thresholds are highly variable among individual humans, and thus
the
maximum useful temperature would be similarly variable. As described above,
the heat endurance of the animal may also vary with the duration of
application,
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as higher temperatures may be tolerated for shorter periods of time than what
would be typically used for lower temperatures. In one embodiment, the
temperature of the volume of air can be from about 54 C to about 65 C. In
another embodiment, the temperature of the volume of air can be from about 54
C to about 59 C. In yet another embodiment, the temperature of the volume of
air can be about 59 C.
In one embodiment, heated air may be applied to the target area with an
airflow of from
about 45 ft3/min to about 365 ft3/min or from about 170 ft3/min to about 490
ft3/min 26, such that
the heated air impinges directly on substantially all ectoparasites located
within the target area.
Airflows within this range tend to be above airflows that can be generated by
consumer blow dryers, and are thus more aptly suited to an institutional
environment. In another embodiment, the airflow can be from about 50 ft3/min
to
about 150 ft3/min.
In a further embodiment of the institutional method, the heated air can be
maintained at the target area for from about 5 seconds to about 1 hour 28. In
general the heated air should be maintained at each target area for a time
sufficient to ensure eradication of the ectoparasites within that region. In
another
embodiment, the heated air is maintained at the target area for from about 10
seconds to about 30 minutes. In yet another embodiment, the heated air is
maintained at the target area for from about 20 seconds to about 60 seconds.
It
is intended that the terms "eradication" and "elimination" refer to the
infestation
and not necessarily the ectoparasites themselves. It is not required that all
ectoparasites be dead or physically removed from the region, though dead and
physically removed ectoparasites would be within the scope of the present
invention. In other words, even if a portion of the ectoparasites in a region
survive but are no longer viable following treatment according to aspects of
the
present invention, the infestation would still be considered eradicated or
eliminated. Similarly, an infestation where one or more viable ectoparasites
of
the same sex survived but were unable to mate due to a lack viable
ectoparasites
of the opposite sex would also be considered eradicated or eliminated.
As shown in FIG. 3, In defining a target area, the length of the individual's
hair may be relevant to the eradication procedure. As such, one embodiment of
the present invention may provide a method 30 including steps of determining
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that the human having an ectoparasite infestation has a hair length suitable
for
sectioning 32, dividing the hair into a number of discrete sections to expose
a
plurality of scalp areas 34, and sequentially applying the heated air to each
discrete section of hair associated with each of the plurality of scalp areas
36.
The discrete sections of hair may be separated with, without limitation, human
fingers, clips, rubber bands, elastomeric fabric, wires, combs, pins,
barrettes, and
combinations thereof. Furthermore, the term sequentially is intended to
describe
a methodical, systematic order of treating the plurality of scalp sections to
ensure
that the entire infested area is treated, thus more efficiently eradicating
the head
lice infestation. The temperature of the heated air applied to each of the
plurality
of scalp sections may be maintained for a period of time and at an airflow as
described above. Additionally, it may be beneficial to apply the heated air to
multiple sides of each discrete section of hair to eradicate those head lice
that
may be blocked from the airflow by the sectioned hair on one side.
The inventors have found that ectoparasite mortality rates can be
increased by the following method of dividing hair. This method is not
intended to
be limiting, but is merely provided as one example of dividing hair into
discrete
sections. Other methods of systematically applying heated air to all infested
areas would also be considered to be within the scope of the present invention
as
claimed. The human's hair should be combed thoroughly with a standard comb
prior to treatment to remove tangles or snarls. The hair is then parted down
the
middle of the scalp, and one side is clipped up with a large hair clip. On the
opposite side, the hair is sectioned into squares of about 2 inches by 2
inches, for
a total of about 7-10 sections on one side, depending on the thickness of the
hair.
One method of sectioning can begin along the part on the top of the head,
beginning at the forehead, and proceed along one side of the part to the back
of
the neck. Each square of hair can be twisted tight at the base of the hair and
secured with a standard butterfly clip. Below the first row of square
sections, the
remaining hair can be sectioned into similar squares around the ear. The
procedure is then repeated for the other side after removing the large hair
clip.
Following sectioning, the treatment can be started with the lowest section in
front
of the ear on one side. This section is unclipped and the hair held with one
hand
about three inches from the scalp. It may be helpful to hold the hair loosely
to
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facilitate the passage of the heated air. The heated air may be delivered near
the
surface of the scalp at an angle of about 45 degrees to the scalp. The heated
air
may be delivered from one direction for about 30 seconds, while holding the
device delivering the heated air motionless. The hair may be held such that it
parachutes out to let the heated air flow through it. The heated air is then
delivered in a similar manner to the other side of the square for
approximately 30
seconds. The hair is re-clipped following treatment. Each square section is
treated sequentially moving back toward the neck in a similar manner, until
the
entire head has been treated.
As shown in FIG. 4, the institutional method can further include a step of
40 systematically applying heated air to the target area utilizing a device to
separate and lift hair within the target area 44. The device to separate and
lift
hair can be a comb device. This combing method may be utilized due to the
difficulties of physically sectioning shorter hair into discrete scalp
sections,
coarser hair, etc. It should be noted, however, that the length and coarseness
of
the human's hair is not limiting as to which method embodiment is utilized,
and .
that alternative embodiments are presented solely to provide more convenient
means of accomplishing the eradication of head lice. For example, short hair
that
may be difficult to section can still be divided into scalp sections as
described in
the previous embodiment without departing from the scope of the present
invention. Similarly, it is contemplated that utilizing a comb device is not
limited
to hair that is difficult to section, and is thus contemplated in cases
involving
longer hair.
The inventors have discovered that ectoparasite mortality rates can be
increased by the following method of utilizing a comb device. This method is
not
intended to be limiting, but is merely provided as one example of utilizing a
comb
device. Also, the following method appears to increase mortality rates for
both
long and short hair, and is thus not limited by hair length. The human's hair
should be combed thoroughly with a standard hair comb prior to treatment in
order to remove any tangles or snarls. The hair should then be parted down the
middle of the scalp. The comb device can be used to introduce the heated air
starting at the forehead end of the part. The teeth of the comb device should
be
oriented such that the heated air blows over the top of the human's head. The
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comb device can be slowly pulled down the side of the human's scalp, towards
the sideburn. Each pass should take about two minutes such that substantially
all areas of the scalp are exposed for at least 30 seconds. This speed is
approximately about 1 inch in 20 seconds for many situations. These downward
movements are repeated moving from the front to the back of the human's head,
overlapping slightly with each pass. Next, the comb device is placed on the
sideburn with the teeth facing over the ear and towards the back of the head.
The comb device can be drug over and around the back of the ear at the same
speed as previously described. The teeth of the comb device should be in
contact with the scalp for most of the treatment. Next, with the human's head
tilted forward to expose the back of the neck, the comb device is drug from
the
base of the neck up to the crown on the head at the speed previously
described.
These procedures are repeated until substantially all of the head has been
covered. '
One example of a comb device to lift and separate hair at the scalp while
maintaining an airflow of heated air is shown in FIG. 5. The comb device 60 is
not intended to be limiting, and is shown solely as an example of how such a
device might be embodied. Any device which provides an airflow of heated air
to
the scalp while lifting and separating the hair would be considered to be
within
the scope of the present invention. Various motions are contemplated whereby a
comb device can be utilized, including, without limitation, pushing motions,
pulling
motions, sliding motions, etc. In this embodiment, a cylindrical tube 62 may
be
coupled to a source of heated air at a proximal end 63, such that the heated
air
would flow in a direction indicated by the arrow 72. The cylindrical tube 62
may
be coupled to a distal tube 64 having a beveled end 67 and an airflow opening
70. The distal tube 64 may be coupled to the cylindrical tube 62 by a
connector
66 or any other attachment means known to one skilled in the art. Also, the
distal
tube 64 and the cylindrical tube 62 may be constructed from a single tube with
an
airflow opening 70 and a beveled edge 67. The comb device 60 also includes a
comb 68 coupled to the beveled end 67 of the distal tube 64. The teeth of the
comb 68 can be inclined in a direction that is generally opposite the general
direction of airflow 72 from the tube 62. It is also contemplated that the
comb can
be formed from a portion of the tube. This configuration allows the heated air
to
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flow in direction 72 from the heated air source, through the cylindrical tube
62 to
the distal tube 64, and out the airflow opening 70. As such, heated air is
forced
out of the comb device 60 at the scalp areas as the comb 68 is lifting and
separating the hair. This action in effect directs the heated air to the roots
of the
5 hair and along the length of the hair to the locations where lice often
reside.
It is contemplated that any configuration of comb device known to one
skilled in the art that can act to separate and lift hair would be within the
scope of
the present invention. These devices can include teeth oriented generally
opposite to the general direction of the airflow, oriented generally in the
same
10 direction of the airflow, or any other configuration known to one
skilled in the art.
Opposite is intended to include orientations that are greater than 900 to the
direction of the airflow.
Also, all configurations of devices to apply heated air to the target area
known to one skilled in the art are considered to be within the scope of the
15 present invention. In one aspect, heated air can be generated and blown
through
the hair into the room air. In another aspect, heated air can be recirculated
through the device, thereby reducing the overall power demand of the device by
conserving and/or reusing pre-heated air. Suction devices are also
contemplated. It may be beneficial to apply suction opposite to the heated air
in
order to affect heated air recirculation and/or to more expeditiously remove
dead,
dying, and living lice and eggs that are shaken loose from the hair. In
another
aspect, a filter can be utilized in the device to catch the lice, eggs, and
debris,
and thus act to minimize many of the safety threats accompanying the
collection
and disposal of blood containing organisms.
Though it is preferred that the treatment be performed in an institutional
setting in order to obtain the best possible results from the treatment, i.e.
total
elimination of the ectoparasite infestation, handheld methods that will most
likely
be used at home are also considered to be within the scope of the present
invention. It is likely that handheld methods of treatment will involve
devices that
produce lower airflows than the institutional devices utilized in the methods
described above. As such, the effectiveness of the handheld methods may be
somewhat lower than what is seen in a institutional environment. In such
cases,
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effective eradication of an ectoparasite infestation may be accomplished
through
multiple treatments.
As such, FIG. 6 shows one embodiment of the present invention that
provides a handheld method for eliminating an ectoparasite infestation 80. It
is
intended that the term handheld refer to blow dryers and the like that can be
purchased and used at home. In some cases, particular handheld blow dryers
may be classified as institutional devices due to higher airflows of these
particular
models. This handheld method may include steps of defining a target area on a
human having an ectoparasite infestation 82, heating a volume of air to a
temperature of from about 50 C to about 100 C to form heated air 84,
applying
the heated air to the target area with an airflow of from about 20 ft3/min to
about
220 ft3/min 86, such that the heated air impinges directly on substantially
all
ectoparasites located within the target area, and maintaining the heated air
at the
target area for a period of time sufficient to affect an ectoparasite
mortality rate of
at least 50% 88. The time period may be continuous or discontinuous, as
described above.
In one embodiment of the present invention, the treatment can be
performed with a blow dryer having an attached comb device. The comb device
can be of any configuration known to one skilled in the art, such as, without
limitation, the device 60 as shown in FIG. 5. In this case, temperature and
airflow
will be dependent on the particular blow dryer utilized. It is assumed,
however,
that temperature and airflow will be within the above recited ranges. In one
embodiment of the present invention, the temperature of the volume of air can
be
from about 54 C to about 65 C. In another embodiment, the temperature of the
volume of air can be from about 54 C to about 59 C. In yet another
embodiment, the temperature of the volume of air can be about 59 C.
Regarding airflow, in one embodiment, the airflow can be from about 25 ft3/min
to
about 125 ft3/min. Also, though ectoparasite mortality rates may be highly
variable in handheld methods given the lower airflow and inexperience of the
individual performing the treatment, in one embodiment the heated air can be
maintained at the target area for a period of time sufficient to affect an
ectoparasite mortality rate of at least 70%. In another embodiment the heated
air
is maintained at the target area for a period of time sufficient to affect an
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ectoparasite mortality rate of at least 85%. In yet another embodiment the
heated air is maintained at the target area for a period of time sufficient to
affect
an ectoparasite mortality rate of at least 95%. These mortality rates may be
the
result of a single treatment or they may be the combined rates following
multiple
treatments.
Given the lower airflow rates of some blow dryers, the comb device may
allow the hair to be lifted and separated and thus further facilitate the
delivery of
the heated air directly to the ectoparasites within the infested region. Note
that
the comb device 60 of FIG. 5 is oriented such that the hair is lifted and
separated
by a pulling motion rather than the pushing motion of current standard blow
dryer
attachments. Other embodiments may include comb devices utilizing push
motions, which are also considered to be within the scope of the present
invention.
As has been discussed above, previous inaccurate airflow ranges were
obtained through the use of a pitot tube anemometer. Such devices utilize a
velocimetric method for measuring airflow. Velocimetric flow is given as the
linear movement of gas per unit time, with feet per second (fps) being a
common
unit. The use of velocimetric data may be employed in some cases because the
measurement of air velocity can be readily undertaken by the use of simple
devices. Once the velocity of airflow is determined, the linear data is
converted
into volumetric data by integrating over the cross-sectional area of the
conduit,
i.e. multiplying the cross-sectional area of the conduit by the linear
airflow. It
appears that this measurement technique may result in a high degree of
inaccuracy because the linear airflow is both nonlaminar (i.e. is not always
directed straight downstream) and inconsistent (i.e. is not a constant
velocity
across the section of the conduit). Thus, velocimetric airflow may not be a
reliable
method of describing airflow in most applications.
Alternatively, volumetric airflow is given as volume passing a specific point
or plane per unit time, with a common unit being cubic feet per minute
(ft3/min or
cfm). The inventors believe that volumetric airflow measurements may be a more
accurate means of describing airflow since cross-sectional nonlaminarity and
velocity inconsistency do not grossly affect the resulting data. This is
because
volumetric airflow is the amount of air volume passing through a conduit per
unit
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time, regardless of microcurrent movement. It is believed that such volumetric
measurements may provide a more accurate description of reported airflow range
values. Non-limiting methods for measuring volumetric airflow are described in
the Examples below.
EXAMPLES
The following examples of airflow measurement methods are provided to
promote a more clear understanding of certain embodiments of the present
invention, and are in no way meant as a limitation
Example 1
A pitot tube anemometer (Dwyer model 166-12 pitot tube connected to a
TSI DP-CaICTM digital rnicromanonneter) was utilized to measure the airflow of
a
standard hair blow dryer. A linear airflow velocity (in ft/min) was measured
at 24
points across the orifice of the blower and a "correction factor" was
determined
that related the airspeed in the center of the orifice to the average airspeed
across the orifice. One hundred airspeed measurements were then taken in the
center of the orifice, and averaged. The correction factor was then applied to
the
average airspeed. The corrected airspeed was then multiplied by the cross-
sectional area of the orifice to give volumetric airflow in cfm.
The measured airflow for the hair blow dryer was 170 cfm using the pitot
tube. Because the airflow was partially obstructed by heating elements near
the
outlet orifice, the airflow was normalized by attaching a 2-foot length of
11/2 inch
inside diameter PVC pipe to the outlet orifice. In this way, it was envisioned
that
the airflow would enter the pipe in a turbulent flow but would achieve
normalized,
semi-laminar flow by the end of the pipe. The velocimetric airflow was then
determined as described above and converted to volumetric airflow. This
measurement is shown in Table 1.
Example 2
The pitot tube anemometer and linear airflow velocity measurement
method of Example 1 was utilized to measure the airflow of a wall-mounted
blower of the type used to dry hands in a restroorn. The measured airflow for
the
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Wall Mounted blower was 490 cfm. This airflow was taken directly at the
orifice of
the blower. This measurement is shown in Table 1.
Example 3
The pitot tube anemometer and linear airflow velocity measurement
method of Example 1 was utilized to measure the airflow of a custom built
blower,
herein labeled custom blower 1. The measured airflow for this device was 450
cfm. This airflow was determined by placing the pitot tube directly in the
airstream after a full length of flexible hosing (65 inches). A temperature of
55 C
was measured at the hose orifice. The ambient room air temperature was ¨25 C
and ambient room relative humidity was ¨50%. This measurement is shown in
Table 1.
Example 4
The pitot tube anemometer and linear airflow velocity measurement
method of Example 1 was utilized to measure the airflow of a custom built
blower,
herein labeled custom blower 2. The measured airflow for this device was 361
cfm. This airflow was determined by placing the pitot tube directly in the
airstream
after a full length of hosing (65 inches) with the internal temperature set at
63 C
through the use of a closed-loop digital temperature controller. This results
in a
59 C temperature at the hose outlet orifice (temperature decline due to
conductive and radiative heat loss through the hose wall). The ambient room
air
temperature was ¨25 C and ambient room relative humidity was ¨50%. This
measurement is shown in Table 1.
Example 5
Airflow measurements were determined by a Bulk Volumetric method as
follows: A large bag was constructed out of plastic. Specifically, 40 inch
continuous polyethylene tube stock (40 inches wide, or ¨25.5 inches in
diameter),
.004 inch thick, was cut to a length of 181.5 inches. The ends were sealed
with
adhesive packaging tape, except for a small opening in the corner of one end
of
the bag corresponding to a diameter of approximately 2.5 inches. The fully
inflated bag was modeled using a 3D parametric CAD system by first inflating
the
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bag and taking measurements of the outside bag dimensions. Using this model,
the inflated volume of the bag was calculated at 83,000 cubic inches +/¨ ¨5%.
Each of the devices of Examples 1-4 were separately used to inflate the fully
collapsed bag through the small end opening and the time to complete inflation
5 was recorded. These measurements were iterated 10 times with each device
=
and the average time of inflation was calculated. The volume of the bag was
then
divided by the average time required to fill the bag to give airflow in cfm.
These
measurements are shown in Table 1.
10 Example 6
Airflow measurements were determined by a Bernoulli's orifice flow meter
method as follows: A Bernoulli's flow meter was constructed from PVC pipe and
a precision thin steel plate. Each of the blower devices of Examples 1-4 were
attached to the flow meter and a pressure difference was taken in chambers on
15 either side of the plate. A Bernoulli's equation written in Microsoft
Excel converted
the air pressure difference to velocimetric airflow. The equation was then
used to
convert each pressure difference to airflow in cfm. These measurements are
shown in Table 1.
20 Table 1: Measured airflow values for Examples 1-7
Device Manufacturer Pitot Tube Bulk
Bernoulli's
Reported Value
Volumetric Flow Meter
Bonnet-style Dryer 9 10
Blow Dryer A 580 170 41 33 Note 1
Blow Dryer B 170 102
Wall Mounted 170 490 103 Note 2
Custom blower 1 720 Note 4 450 113 Note 3
Custom blower 2 720 Note 4 361 88 93
Low-power custom 360 Note 4 87 89
blower
Note 1 ¨ the blow dryer lost a small amount of airflow through the rear of the
fan housing.
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Note 2 ¨ the housing of the wall mounted blower was designed to vent air
elsewhere when pressure increased at the outlet orifice, so this method was
inapplicable.
Note 3 the custom blower 1 had too high an airflow to be measured with the
flow meter used.
Note 4 ¨ these values were calculated from velocimetric data provided by the
manufacturer,
- As has been stated, the airflows originally reported in the previously filed
U.S. Patent Application (Publication No. US 2005/0261740) were measured using
a pitot tube
anemometer. Table 1 shows data measuring the same airflows using at least two
different methods described above. Airflow data from a bonnet-style hair dryer
and from a low-power custom blower have also been included. The Bulk
Volumetric method is simple and greatly reduces both experimental and
calculational error. The Bernoulli's Thin Plate Orifice Flow-meter method was
used to validate the data derived from the Bulk Volumetric method for those
devices for which the flow meter method could be utilized. Because these two
methods utilize different principles yet the values obtained generally
correlate to
within 41- 5cfm (-5%) of each other, these values may be more accurate and
consistent than the values reported in the previous application.
Example 7
Manufacturer A reported an airflow of 580 cfm for blow dryer A.
Manufacturer B reported an airflow for a substantially more powerful blow
dryer B
to be 170 cfm. The Bulk Volumetric method of Example 5 was utilized to -
measure the respective airflows from blow dryers A and B. The airflow of blow
dryer A was measured to be ¨41 cfm, while the airflow of blow dryer B was
measured to be ¨102 cfm. Thus the Bulk Volumetric method measured relative
airflows from the blow dryers as expected, with the substantially more
powerful
blow dryer having the higher airflow.
it is to be understood that the above-referenced arrangements are
illustrative of the application for the principles of the present invention.
Numerous
modifications and alternative arrangements can be devised without departing
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from the scope of the present invention while the present invention has
been shown in the drawings and described above in connection with the
exemplary embodiments(s) of the invention. It will be apparent to those of
ordinary skill in the art that numerous modifications can be made without
departing from the principles and concepts of the present invention.
