Employing Solar Powered Mosquito Traps

By SunNight Solar

11264 Memorial Drive Houston, TX 77024

713-408-2485

2

Table of Contents

Introduction and Background.................................................................................................3

Summary of Scientific Research.............................................................................................5

Common Characteristics of the Target...................................................................6

Detailed Description of the Proposed Device...................................................................7

Detailed Description of Component Parts............................................................8

Heating Element.................................................................................................8

Bottle.......................................................................................................................9

Phase Change Material.....................................................................................9

Clear Chimney...................................................................................................10

Trap Assembly..................................................................................................12

Attractant Cup...................................................................................................13

Sweatband..........................................................................................................14

Operation and Use......................................................................................................................15

Experimental Prototypes........................................................................................................17

Alternative Applications..........................................................................................................19

What Not to Use.............................................................................................................19

Crowd Source Data Collection and Research ...................................................20

Manufacture..................................................................................................................................21

Distribution...................................................................................................................................21

Advertising Opportunities......................................................................................................21

Intellectual Property.................................................................................................................21

Financial Information...............................................................................................................23

Appendices....................................................................................................................................25

3

Introduction and Background

Malaria in humans results from infection with the Plasmodium protozoan

transmitted from one person to another by the female Anopheline mosquito. According to reports from the World Health Organization, Malaria causes as many as 3 million deaths worldwide annually.

This proposal presents the design of a unique and inexpensive passive solar

powered trap that can be used to eliminate mosquito populations within a human habitat. (See Illustration 1). This trap resulted from collaboration between the Rockefeller Foundation, the cloud sourced company Innocentive (InnoCentive's unique Challenge Driven Innovation approach leverages open innovation and crowdsourcing to help organizations solve pressing Challenges) and the Houston based company SunNight Solar.

The first section of this proposal presents a brief summary of the scientific

research that has been conducted into the host search mechanisms and preferred feeding characteristics of the Anopheline mosquito. (It is noted that the latest findings in this field of research provides the basis for the design of the proposed trap product.)

The second section of this proposal presents the basis of the overall product

concept along with the design details and function of the individual component parts.

A third section of this proposal deals with how the initial product is to be

used. The fourth section presents a number of other subjects, including, possible

alternative markets for the initial product and other possible product offerings. The fifth section describes two functional prototypes that were built based

upon this design and presents results of initial testing to prove the effectiveness of the concept.

Multiple appendices are included at the end of this proposal to provide

important references in support of the summations included in the 15 pages of text.

4

Illustration 1: Solar Powered Mosquito Trap1

1 A representation of a standard No. 2 pencil is used in many of the illustrations to convey the actual size of the proposed trap. Furthermore, the various colors are used only for differentiation of the parts and can change for improved aesthetics.

5

Summary of Scientific Research

Up to 60 different species of the genus Anopheles constitute vectors of human malaria in different regions of the world. The implication of this reality is that many different mosquito species must be controlled to have an effective global impact on eradicating this deadly disease. Furthermore, it must be stressed that mosquitoes are opportunistic. Therefore, additional vectors may emerge as human migration and invasive land use continues to change regional ecologies. (See Appendix A).

However, regional ecological changes are not the only concern to be addressed. Research in global climate changes have led to some dire predictions of increased human cases of malaria around the world as mosquito populations move northward.

Finally, it has been proven that anthropophilic mosquitoes transmit other arboviruses... such as those responsible for yellow fever, dengue hemorrhagic fever, epidemic polyarthritis, and several forms of encephalitis.

Given all of the above issues, it is apparent that there are many applications and many different markets, in both developed and developing countries, for a well-designed device that effectively eliminates disease vector mosquitoes.

Illustration 2: Distribution of Malaria Around the World

6

Common Characteristics of the Target(s)

In order to design the best product possible, it is critical to analyze the scientific literature for common host search mechanisms and blood feeding habits of anthropophilic mosquitoes (specifically females of the Anopheles species). In summary, the latest research clearly shows that mosquitoes are attracted to their human blood hosts by the combination of the following factors when inside a human habitat2:

1. The temperature of human extremities during rest (~29+/- 3°C),

2. Moisture emanating from the skin, and

3. The complex, multi-component scent of human sweat and resident microflora.

Illustration 3: Anopheles Gambiae

2 There has been a great deal of scientific research into how carbon dioxide and visual clues act as mosquito attractants. However, when the research is evaluated in detail, it is apparent that CO2 and visual indicators are used by the mosquito only when coming from a distance. These attractants have little, or no effect within an enclosure. Supporting details and references are provided in Appendix A.

7

Detailed Description of the Proposed Device

Overall, this device is designed to effectively attract, trap, and kill the female Anopheles mosquito by using a complete combination of the above three attractants.

More specifically, this unique trap uses a nontoxic phase change material (PCM) to retain passive solar heat during the day. This stored heat is released when the unit is brought in out of the sun (when the mosquitoes are feeding). This heat, in combination with a natural convection chimney, distributes a liquid-based mosquito attractant.

One other unique aspect of this design is that the attractant suggested for use in developing third world countries is simply a small amount of water combined with human sweat (collected in a sweatband during the day). Thus, heat, moisture, and, scent are all present! The mosquitoes are trapped in a container and die by dehydration.

Illustration 4: Exploded View of the Trap Sub-Assemblies

8

As seen in Illustration 4, above, there are four sub-assemblies involved in this product offering. It is noted that all the required components are simple to manufacture employing inexpensive, environmentally friendly materials and uncomplicated tooling.

Please understand that this unit does NOT require any expensive electrical elements or storage batteries in its construction. Therefore, the device is a very intuitive to understand, simple to use with little instruction, and most importantly, easy to maintain without tools. The estimated cost for the assembled and packaged product is less than US$6.25, based upon the current size and US vendor quotes for the plastic components.

Detailed Description of Component Parts

Heating Element: Illustration 5 shows a perspective and partial

sectional view of the passive solar heating element, which is the core component of this device. The heating element consists of an injection blow molded bottle containing approximately 1 liter of PCM. The sizing of this component is based upon storing 10 hours of heat.

The proposed heating element represents a simple application of passive solar energy. The bottle is flat black to effectively collect solar radiation during the day and transmit that heat though the thin bottle walls into the PCM (3). The low melt temperature PCM absorbs the thermal energy during the day and releases it at a constant temperature at night, when needed.

Illustration 5: Phase Change Heating Element

9

Bottle: The bottle is injection blow molded from black high-density

polyethylene (HDPE). This material is readily available around the globe and easily processed in inexpensive molds without toxic out-gassing.

The sides of the bottle have a hyperbolic curve to them in order to provide airflow as described below. The top of the bottle has a standard bottle thread to mate with the cap incorporated into the clear chimney component described on page 7.

The bottom of the bottle incorporates a conical cavity for three reasons:

1. The distance from the outer wall to the inner most phase change material is reduced so as to improve melting;

2. The cavity engages a center section of the attractant cup having the same taper to support and position the two relative to each other; and

3. The assembled product can be mounted on top of a pole with reduced chance of tipping.

Phase Change Material: Depending upon availability and local cost, the

phase change material (PCM) used in the device can be one of the following four materials3:

1. Petroleum based refined paraffin wax (linear crystalline alkyl hydrocarbons (CnH2n+2));

2. Fatty acids (CH3(CH2)2nCOOH)

3. 100% soy or vegetable oil wax (given their sustainable nature and inherent low melting point), or;

4. Inorganic salt hydrates (MnH2O)

3 See: http://en.wikipedia.org/wiki/Phase_Change_Material. A list of commercial suppliers of candidate PCM materials, along with possible product model numbers of the relevant products is provided in Appendix B. (Note: If soy or vegetable wax is selected for the PCM, any excess supply capacity can be used to provide a corollary product, clean burning fuel for cooking. In addition, these plant-based waxes are relatively inexpensive to manufacture, making it a very attractive sustainable choice.) Depending upon the PCM selected, there can be as much as a 10% volume change with phase, so the bottle must be somewhat elastic, or pleated, or have some air space to reduce the peak pressure seen. Furthermore, the bottle needs to be well sealed to avoid losing or gaining water from the surrounding air.

10

For the depicted configuration, the 1 liter of PCM needs to have a relatively consistent melt temperature of between 40 and 50 ° C (105 to 122 °F). This melt temperature was determined by analysis and testing to result in an output air temperature from the device of the desired 26 to 31 degrees. Note that additives can be mixed into the phase change material to adjust the PCM melt temperature to the exact range required if the final design takes a different configuration.

Illustration 6: Phase Change Wax

Clear Chimney: A clear plastic chimney is placed over the outside of the

phase change element. A threaded top cap is incorporated into the top of the chimney component to seal the bottle, as mentioned above, while also holding the two parts together. Once assembled, there is no need for these two components to ever come apart.

The very top of this injection molded polycarbonate part has a simple hook for hanging by a wire.

The length of the chimney is made the same as, or slightly longer than that of the bottle. This is done so that the assembly can be set in the sun without effect from breezes.

There are three holes around the top surface for mosquitoes to pass through and into the trap. The holes are large enough to clear the 9.0mm wingspan of the largest Culex mosquito.

11

The indentations molded into the sides of the clear chimney hold it concentric with the heating element bottle and to maintain a gap between the two components.

Notice that the sides of the chimney are tapered similar to, but not exactly the same as those of the bottle. The sidewalls of the phase change bottle and the clear conical chimney parts form a concentric gap that varies hyperbolically along the vertical axis. This is done in order to generate a natural airflow as the air is heated by the phase change assembly. The analogy for this feature is a hyperbolic cooling tower used outside of power generation plants. By using a small version of this device, no powered fan is needed to distribute the heated, moist scent throughout the habitat. The induced heated airflow also helps direct the mosquitoes up the hyperbolic gap, through the trap holes in the chimney, and into the trap assembly.

Illustration 7: Heating Element with Chimney

12

Mosquito Trap Assembly: As shown previously in Illustration 1, a trap

assembly sits on top of the heating element/chimney assembly (depicted in blue). Illustration 7 shows the removable two-part trap assembly and the removable top component. These are removable so that dead mosquitoes can be removed, as needed. Holes in the trap body line up and positively mate with the clear chimney trap holes when the trap is reinstalled.

Both parts of the trap assembly are injection molded plastic (HDPE or Polypropylene). The trap top is ventilated to allow the moist, scented air to flow through.

Note that the proposed trap assembly incorporates an often-used tortuous path so that mosquitoes cannot escape once they enter4. There is a small clearance between the center core of the trap body and the bottom of the snap on cover. No fan or adhesive element is needed to retain the prey.

An alternative design for the trap uses a scrap piece of bed netting in place of the top. The bed netting could be held in place with a rubber band. If the bed netting were treated with insecticide (ITN), any lighting mosquitoes would be destroyed.

Illustration 8: Trap Top Assembly

4 A detailed description of a simple, tortuous path bug trap can be found at: http://www.pestcontrolcanada.com/INSECTS/wasp_traps.htm

13

Attractant Cup with Wicks: As mentioned above, moisture and scent

are required for effectively attracting mosquitoes when in the vicinity of their host. The moisture and scent generated by this trap is provided by a small amount of water containing human sweat held in the attractant cup at the bottom of the assembly (see Illustration 8).

Note that the center of the attractant cup is conical to mate with the cavity in the bottom of the heating element bottle. In addition, there is a hole through the center to allow the product to be mounted to a pole, if ever deemed appropriate.

It is envisioned that the attractant cup would be injection molded from HDPE or polypropylene. Ideally, this part would have a dark color to attract, rather than deter mosquito activity around the base of the product.

A few simple wicks which are die cut from cotton cloth are clipped around the perimeter of the attractant cup and draw the attractant liquid into the airstream. The bottom of the attractant cup is slightly convex and sloped to the outside so that remaining fluid is always in contact with the wicks.

Illustration 9: Attractant Cup with Wicks

14

Sweatband: A vast amount of scientific research has been done on how to

best attract and repel anthropods. ALL of this research shows conclusively that the mosquito consistently prefers human kairomones (odors) to all other attractants. Therefore, we suggest that the attractant used in developing, third world countries be simply based upon human sweat and body odors (collected in a cotton sweatband worn by an adult around the ankle.)

It is noted that using sweat is a very simplistic approach, but it makes sense in so many ways. First of all, sweat has been scientifically and experientially proven to work. Therefore, this simple solution can be implemented immediately without further research. Secondly, there will always be a FREE supply of axillary human sweat in the household... or from a more pungent “supplier” in the region. Thirdly, research has found more volatile compounds that attract mosquitoes in adult axillary sweat than found in other human fluids or artificially derived compounds.

Note that the ankle is the preferred site for the cotton/elastic sweatband as a number of researchers have proven the effectiveness of foot odor as an attractant over other human scents. See Appendix A for more details.

Illustration 10: Sweatband

15

Operation and Use

At the start of each day, the heating element/ clear chimney assembly is removed from the attractant cup and placed on the ground, roof, or table outside the home where it can be exposed to the full sun. At the same time, the sweatband is put around the ankle of the adult resident whom mosquitoes most frequently bite.

The phase change material within the black bottle melts during the day by absorbing heat from the sun. The phase change assembly can be stood upright or laid on its side. If stood upright, the flat surface of the chimney resting on the surface cuts off airflow through the hyperbolic gap and diminishes any cooling effect of wind or breezes. Nothing will be damaged if it rains or tips over!

As the PCM heats up in the sun, the sweatband (or, alternatively, a cotton sock) will collect some sweat and foot odor from the “donor”.

At the end of the day, prior to dusk, the sweatband is wetted with a few CC's of water and the scented water transferred into the attractant cup. The warmed heating element assembly would be placed back on top of the attractant cup with the conical surfaces ensuring alignment. The trap would be placed on top of the heating element, if it had been removed. Note that leaving the trap in place while the sun heats the unit may hasten the death of any enclosed mosquitoes.

At this point, it is recommended that the heated unit be placed in a dark corner downwind of beds or people in the habitat. The reason for this is that the traps should be located in inconspicuous locations where they will not be disturbed or vandalized. Furthermore, mosquitoes search for hosts by traveling upwind, guided by scent.

The product can be placed on the ground (with the attractant cup providing an insulating thermal break for the heating element), on a tabletop, hung by a wire hook, or a pole up through the center of the attractant cup and heat element bottle. The design offers this wide flexibility since not all mosquito species fly at the same height from the ground.

Once inside the habitat, the heating element will begin to release its stored heat. Heated air, laced with the moisture and scent from the cotton wicks, will flow up through the hyperbolic gap between the bottle and chimney. The air will exit through the openings in the top of the trap and distribute downwind to start attracting local mosquitoes. Very intentionally, there is no CO2 present in the air so as to avoid attracting more distant mosquitoes to the habitat.

16

The mosquitoes track the scent upwind to the trap rather than to the humans. They find their way to the wicks only to find no host. The mosquitoes then take off vertically and follow and/or are forced by the convective airflow up through the gap between the bottle and the chimney. They pass through the trap holes into the trap assembly. Once inside the trap, they cannot escape due to the tortuous path.

It is important to monitor the number of mosquitoes in the trap day to day. If after several days the trap does not appear productive, it should be moved to an alternate location, or height. Remember the primary goal is to trap blood-feeding mosquitoes. It is less of a priority to maintain consistent sites that may have poor yields.

17

Experimental Prototypes

Two rough prototypes of this device were built for functional testing. These two prototypes are pictured in Illustration 10 for reference. Prototype A was constructed from standard blow molded bottles and holds approximately 0.75 liters of standard paraffin wax. In comparison, Prototype B is a custom-made bottle having a bottom conical cavity to evaluate this feature. Prototype B was filled with 1 liter of AstorPhase 40B from Honeywell Specialty Waxes. Both bottles included air space.

The following results were obtained when these two prototypes were tested under various environmental conditions:

Prototype A: When set in the full sun, the temperature of the paraffin wax

used in Prototype A started to rise immediately. This confirmed that the black surface is a good heat absorber. The temperature continued to rise until the air in

Illustration 1: Functional Prototypes Used in Testing

18

the black bottle/chimney gap became steady at between approximately 44 and 45 °C. This stabilization of temperature confirms that the wax was melting as expected.

All of the wax in the unit melted when set in the full sun for approximately 8 hours (8:00 am to 4:00pm) in spite of breezes. The clear sleeve works properly

When the heated prototype A unit was brought into a 22 °C. indoor environment, the heated air coming from the trap hole was measured to be steady at between 43 and 44 °C. This elevated air temperature remained approximately the same for 4 to 5 hours before rapidly dropping.

The output air contained sufficient moisture to fog a cold mirror placed over the trap hole. The cotton wick was consistently moist but not dripping wet confirming that water was being transferred out of the prototype attractant cup.

The sweatband around the ankle was not intrusive and was easily washed to provide attractant.

Of particular interest is the fact that a mosquito inadvertently found its way into the plastic bag being used to simulate the trap assembly in one test of this prototype. The scent from the sweatband seems to work. However, malaria vector mosquitoes are required to prove the true effectiveness of the design.

One limitation of this design was that the ambient air temperature needed to be above 30 °C. for the melting to initiate - due to the high melt temperature of the paraffin. It was also noticed that the melting was often not consistent and a large un-melted section was sometimes seen in the bottle after hours of heating.

Prototype B: The test results for Prototype B were similar to those of

Prototype A, except that the wax completely and consistently melted at between 34 and 35 °C. Correspondingly, the output air temperature in the same indoor environment remained at approximately 32 °C. for over 10 hours.

This testing proved that the conical cavity and lower wax melt temperature proved to be beneficial. Furthermore, at least one liter of PCM is required. These refinements have been included in the design shown in the attached 3D Adobe PDF file.

19

Alternative Applications

This design is designed to be used in third world countries to control malaria vector mosquitoes but can be easily adapted to work in different situations. For example, this same product can be used with artificially synthesized kairomones or 1-Octen-3-ol in place of the human sweat as the attractant. In addition, other attractants, such as sex pheramones, can be used in the device to widen the extent of vector control. Therefore, this one product may also appeal to various consumers in developed countries and deal with other target mosquitoes or destructive insects. Refill quantities of the attractant could be sold as replacement products.

The product could also be used to distribute repellents that are activated by heat without needing fuel or electrical energy.

Similarly, the overall size of the proposed product is approximately the size of a human leg for use in an indoor environment (required by the challenge). However, the design can be easily adapted to use outdoors for “removal trapping”. In fact, if approximately 6 larger traps of this design were placed in a pattern, a wider control area may be achieved for an entire village. Such traps would need to be spaced at least several meters apart to completely cover the area.

What Not to Use: We suggest that insecticides or pesticides NOT be

used in this or any product for a number of reasons:

1. The target pest will eventually develop tolerance to them.

2. There is a strong concern about toxicity against other organisms.

3. Chemical insecticides also kill predators of mosquitoes and the resulting reduction of predators may increase vectors as predators usually have longer life cycles than their prey. Vector mosquitoes can thus reestablish their population faster after the application of insecticides than their enemies can, and their numbers may actually become greater than before.

It is also suggested that the Seeker not use CO2 or lactic acid attractants for an indoor unit. These attractants serve as a long-range airborne attractant and can be detected by mosquitoes at distances of up to 10 kilometers. Thus unwanted mosquitoes would be attracted to the protected habitat. The outdoor trap mentioned above will incorporate CO2, but how that is accomplished is beyond the scope of this proposal.

It is also noted that all of the repellents tested by researchers lose their efficiency after a few hours. Repellent technology needs to improve dramatically!

20

Crowd Source Data Collection and Research: The top of the trap

assembly can be made of clear plastic or constructed of netting in order to allow a count of the enclosed mosquitoes. It is highly suggested that each family using the product be encouraged to compile data on their catch each day. This data could be fed back to a central location to monitor mosquito populations while also providing input for continued improvements to the device year after year.

In addition, the most effective procedures for using the device against vector populations can also be determined and disseminated. For example, placing the trap on a table could be most effective in Kenya while mounting on a 2 meter pole might work best in Sudan.

21

Manufacture

The design is simple enough to allow local manufacture and thus create a “local living economy” (as described in Appendix C). In this light, it is estimated that manufacture of these devices can result in creation of 7 jobs per 100,000 units produced. Most importantly, these jobs would be created with a very low initial investment in tooling and W.I.P. inventory.

Distribution

The mosquito traps can be distributed to residents by organizations that are already established and working within the developing world. These organizations include Feed The Children, Samaritan's Purse, UNHCR, and Invisible Children, as well as many other international assistance groups.

Advertising Opportunities:

A special logo may be designed and embroidered onto the sweatband to help market the PCM Mosquito TrapTM product to other families in the area. Furthermore, name brand companies, such as Nike, Adidas, P&G, or Unicef may be enticed into providing free replacement sweatbands as part of their marketing programs.

Intellectual Property

1. All intellectual property rights are the property of SunNight Solar, which has the responsibility for raising the funds required for product development, testing and distribution.

22

Financial Information

Cost Estimates: Based upon low volume production, this indoor

mosquito trap is estimated to cost approximately US$ 6.21. This rough estimate is based upon US vendors and includes packaging and $1.25 in labor, as detailed below.

Phases: This program is being accomplished in a series of logical phases,

with future phases being dependent upon the outcomes of prior phases. It is

important to note that Phase I (Problem Definition) and Phase II (Initial Design)

of the program have already been successfully completed, resulting in a sustainable and appropriate design aimed at manufacture and use in developing countries. Financial assistance is needed to complete the remaining phases on a timely basis.

23

Phase III: We are now entering into Phase III or the Prototype Construction

phase. During this phase, a limited number of working models will be constructed and tested to confirm that the design performs as predicted by computer analysis.

The total cost of phase III is projected to be $25,000, which consists of:

$15,000 directed toward fabrication of fully functional components at Scott Models, a reliable model shop located near Cincinnati, Ohio

$10,000 directed toward Tom Kruer, a Program Engineer also located near Cincinnati (Note that Tom is donating half of his time to the project on an in-kind basis)

$10,000 to fund testing at the University of Florida Institute of Food and Agricultural Sciences (Matching funds may be available from the University of Florida Research Foundation)

Phase III can be started immediately and is projected to last approximately four months

Phase IV: Upon successful completion of the laboratory testing, two

hundred field test prototypes will be constructed and distributed to regions with acute malaria outbreaks during phase IV of the program. These prototypes will be manufactured at reliable vendors in China to minimize costs and allow rapid roll out of the device following completion of the field tests.

The total cost of phase IV is projected to be $70,000, which consists of:

$35,000 investment in injection molds $5,000 directed toward manufacture of 200 fully functional

prototypes $5,000 directed toward Tom Kruer, a Program Engineer $10,000 for shipping expenses from China and to field test locations $15,000 to fund field test research overseas and data collection

More accurate estimates for capital investment and schedule will be obtained upon commencement of the phase. Phase IV would start immediately evaluation of the results of Phase III and is projected to last approximately four months.

24

Appendix A: Scientific Research

Temperature of the Human Skin

F. G. Benedict, W. R. Miles and Alice Johnson The Temperature of the Human Skin Proceedings of the National Academy of Sciences of the United States of America, Vol. 5, No. 6 (Jun. 15, 1919), pp. 218-222

Malaria Vector Mosquitos

- Anopheles gambiae and An. funestus are the primary malaria vectors in Africa while An. arabiensis and An. moucheti are relatively minor, opportunistic species5.

- Anopheles hermsi and An. freeborni are the primary malaria vectors in N. America6. - Anopheles darlingi is the major malaria vector species in the seven countries

of Central and South America7. - In northeastern Amazonia, Anopheles marajoara, has been found to be the

principal malaria vector as land use changes8. - At the same time, nearly 45 species of Anopheles mosquito have been

implicated in the transmission of malaria in India, including: A. culicifacies, A. fluviatilis, A. minimus, A. philippinensis, A. stephensi, A. sundaicus, and A. leucosphyrus9.

5 FH Collins and NJ Besansky, Vector biology and the control of malaria in Africa Science 24 June 1994: Vol. 264. no. 5167, pp. 1874 – 1875 DOI: 10.1126/science.8009215 6 Anopheles hermsi, probable vector of malaria in New Mexico. Am J Trop Med Hyg. 1993 Oct;49(4):419-24. 7 S Manguin, et. Al. Population structure of the primary malaria vector in South America, Anopheles darlingi, using isozyme, random amplified polymorphic DNA, internal transcribed spacer 2, and morphologic markers. Am. J. Trop. Med. Hyg., 60(3), 1999, pp. 364-376 8 JE Conn, RC Wilkerson, MN Segura, RT de Souza, CD Schlichting, RA Wirtz, and MM Povoa Emergence of a new neotropical malaria vector facilitated by human migration and changes in land use. Am. J. Trop. Med. Hyg., 66(1), 2002, pp. 18-22 9 Nagpal BN, Sharma VP. 1995. Indian Anophelines. Oxford and IBH Publishing Co. Pvt. Ltd.

25

Blood Feeding Habits of Mosquitoes: Different species of

mosquitoes may show strong biting preferences for different parts of the human body (such as the head or feet), which may be related to local skin temperature and eccrine sweat gland output. (de Jong R, Knols BG. Selection of biting sites by mosquitoes.

Bock GR, Cardew G, eds. Olfaction in Mosquito-Host Interactions. New York: J Wiley; 1996:89)

Teun Dekker, et al. Selection of biting sites on a human host by Anopheles gambiae s.s., An. arabiensis and An. Quadriannulatus Entomologia Experimentalis et Applicata 87 (3) , 295–300 doi:10.1046/j.1570-7458.1998.00334.x

Most Anopheles mosquitoes are crepuscular (active at dusk or dawn) or nocturnal (active at night). Some Anopheles mosquitoes feed indoors (endophagic) while others feed outdoors (exophagic). After blood feeding, some Anopheles mosquitoes prefer to rest indoors (endophilic) while others prefer to rest outdoors (exophilic). http://www.malariajournal.com/content/6/1/100

Host Search Mechanisms

Matthew J Kirby et al. Risk factors for house-entry by malaria vectors in a rural town and satellite villages in The Gambia Malaria Journal 2008, 7:2

Knols BGJ: Odour-mediated host-seeking behaviour of the Afro-tropical malaria vector Anopheles gambiae Gilles. PhD Thesis. University of Wageningen, The Netherlands; 1996:213

Aedes aegypti can be guided with great precision to a small target (such as a cylinder 2.5 cm in diameter by 5 cm long) by warm moist convection currents. When the experiment was repeated with malaria mosquitoes Anopheles quadrimaculatus, no alightments could be secured on these small targets, but when the observer's arm was introduced into the observation chamber it was attacked heavily.

R. H. WRIGHT & F. E. KELLOGG Host Size as a Factor in the Attraction of Malaria Mosquitoes British Columbia Research Council: Vancouver 8, Canada. http://www.cdc.gov/malaria/biology/mosquito/

Human Odor as Attractant: Malaria mosquitoes favor the human skin

and not expired air.

26

Willem Takken PhD International Journal of Dermatology Vol. 39 Issue 3 Page 180 March 2000

M. A. H. Braks , R. A. Anderson, and B. G. J. Knols; Infochemicals in Mosquito Host Selection: Human Skin Microflora and Plasmodium Parasites: Parasitology Today Volume 15, Issue 10, 1 October 1999, Pages 409-413

Penn DJ et al Individual and gender fingerprints in human body odour. R Soc Interface. 2007 Apr 22;4(13):331-40.

Curran AM , et al Comparison of the volatile organic compounds present in human odor using SPME-GC/MS. J Chem Ecol. 2005 Jul;31(7):1607-19.

Bar-Zeev, M., et al., "Studies on the Attraction of Aedes Aegypti (Diptera: Culicidae) to Man", Journal of Medical Entomology, 14 (1), 113-120, (Aug. 20, 1977).

Whole-host odors are more attractive than carbon dioxide and lactic acid

alone (Geier M, Sass H, Boeckh J. A search for components in human body odour that attract females of Aedes aegypti. In: Bock GR, Cardew G, eds. Olfaction in Mosquito-Host Interactions. New York: J Wiley;1996:132-48.)

Marieta A. H. Braks Incubated Human Sweat but not Fresh Sweat Attracts the Malaria Mosquito Anopheles gambiae sensu stricto Journal of Chemical Ecology Volume 25, Number 3 / March, 1999 663-672

Allison M. Curran et al Analysis of the Uniqueness and Persistence of Human Scent Forensic Science Communications April 2005– Volume 7 – Number 2

Some of the common bacteria responsible for body odor include micrococci, staphylococci, aerobic and anaerobic corneforms, and pityrosporum species. Apocrine glands enlarge and become active during puberty, and stress can also cause the glands to constrict, developing more sweat from the skin. A woman's body temperature will increase a full degree higher before she perspires, causing men to sweat more than women. Those people with excess hair also sweat more due to their numerous hair follicles where aprocrine glands originate. Caucasians and blacks have more aprocrine glands than Asians, who, as a result sweat less. (http://www.faqs.org/health/topics/69/Body-odor.html)

The results indicate that the trinary blend is more attractive than binary blends, and binary blends are more attractive than single compounds. However, human odors from two of three volunteers were more attractive than the trinary blend. American Mosquito Control Association LABORATORY COMPARISON OF AEDES AEGYPTI (L.) ATTRACTION TO HUMAN ODORS AND TO SYNTHETIC HUMAN ODOR COMPOUNDS AND BLENDS

27

Sweat is not considered an activator but did result in a high probability of Ae. aegypti landing in the study by Eiras & Jepson (1991). Dirty clothes in a hut attracted more mosquitoes than an empty hut.

Parker (1948), using a small glass olfactometer, found sweat to be more attractive than cold moisture, but found warm moisture and a hand to be much more attractive than either. Sweat extract resulted in responses only in conjunction with a heat source in the olfactometer used by Eiras & Jepson (1994).

Foot Odor: Foot odor remained behaviourally active for at least 8 days

after collection on nylon or cotton sock fabric. Basilio N Njiru et al. Malaria Journal 2006, 5:39 Trapping of the malaria vector Anopheles gambiae with odour-baited MM-X traps in semi-field conditions in western Kenya

Knols, B.G., et al., "Limburger Cheese as an Atrractant for the Malaria Mosquito Anopheles gambiae s.s.", Parasitology Today, 12 (4), 159-161, (1996).

Temperature Plus Moisture: Willis (1947) claims that "it has been

known for many years that females of many species of mosquitoes will be attracted to a source of heat." (Willis quotes Howlett 1910). In a recent study by Eiras & Jepson (1994), Ae. aegypti showed a significant response to convection currents in a vertical diffusion two-chamber olfactometer. The presence of a human hand (the attractant) caused an increase of 0.5°C in the upper chamber and 2.8°C in the lower chamber.

Warmth as an attractant must be distinguished from warm moisture. Parker (1948) found warm moisture to be much more attractive than warmth alone; in fact, he considered the presence of a warm object to be no more attractive than the absence of a warm object. In direct contradiction, Khan et al. (1966a) found no difference between attraction to a warm moist flask and a warm dry flask. Both workers were using Ae. Aegpyti. Bar-Zeev et al. (1977) found significantly more attraction to a convection current at 34°C than to room temperature air (26°C). Both were at 40% or both at 60% relative humidity. This significant attraction disappeared when the humidity was removed from the airstreams.

Role of CO2: An. gambiae flew along CO2 plumes, but did not enter the

traps. Teun Dekker Willem Takken and Ring T. Cardé Structure of host-odour plumes influences catch of Anopheles gambiae s.s. and Aedes aegypti in a dual-choice olfactometer.

Takken, W., et al., "Carbon Dioxide and 1-Octen-3-OL as Mosquito Attractants", Journal of the American Mosquito Control Association, 5 (3), 311-316, (Sep. 1989).

28

While CO2 is known to activate the host seeking behaviors of selected species of mosquitoes, it alone is not enough to attract several important anthropophilic (human biting) mosquito species (Schoeler, Schleich, Manweiler and Sifuentes 2004). In fact, baiting traps with only CO2 is not very informative of the Human Biting Rate of a species, which is an important factor in a species' vectorial capacity. CO2 baited traps may disproportionally capture mosquitoes that are less anthropophilic and ornithophilic (Dekker and Takken 1998a). It has been argued since it is ubiquitously excreted by all vertebrates, CO2 is not a reliable indicator of the identity of the host and would not be an important kairomone for species that exhibit a certain degree of host preference, such as anthropophilic species (Takken and Knols 1999).

Gilles, M.T., "The Role of Carbon Dioxide in Host-Finding by Mosquitoes (Diptera: Culicidae) a review", Bulletin of Entomological Research, 70 (1), 525-532, (Mar. 1980).

Insecticide Resistance:

World Health Organization. Resistance of vectors of disease to insecticides. World Health Organ Tech Rep Ser 1980; No. 655.

Roberts DR, Andre RG. Insecticide resistance issues in vector-borne disease control. Am J Trop Med Hyg 1994;50:21.

Removal Trapping: Mass trapping of pest insects by distributing traps

baited with attractive chemicals over a large area is a well known control method. If traps can be made more efficient and cheaper then the method would be more practical. The cost of chemical baits, their attraction radius (effectiveness), and chemical longevity in the field are other important considerations when developing a mass trapping system.

Day, J.F. and R. D. Sjogren. 1994. Vector control by removal trapping. Am. J. Trop. Med. Hyg. 50 Suppl.: 126-133

Technologies that utilize semiochemicals, traps/targets and mass trapping are relatively new for management of adult mosquito populations. To date most of the emphasis has been on developing barriers of attractant-baited and insecticide-impregnated targets. Recently, commercially available traps have been evaluated for their ability to reduce nuisance populations of mosquitoes and resulted in a significant reduction in annoyance caused by the black salt marsh mosquito.

Daniel L. Kline: SEMIOCHEMICALS, TRAPS/TARGETS AND MASS TRAPPING TECHNOLOGY FOR MOSQUITO MANAGEMENT Journal of the American Mosquito Control Association Article: pp. 241–251

29

Appendix B: Commercial Sources for Phase Change Waxes

Honeywell - Astorphase 42B 101 Columbia Road Morristown NJ,07962 http://www.acwax.com/

Nanyang Wax Fine Chemical Plant - Phase Change Energy storage Wax 20# Nanyang city ,Henan Province ,China 473132 http://www.finewax.com/en/product/shownews.asp?newsid=605

RUBITHERM® - RT42 Rubitherm Technologies GmbH Sperenberger Str. 5a, 12277 Berlin http://www.rubitherm.com/english/index.htm

PCM Energy P. Ltd - Latest™36S 1504 Sarkar Tower One, 50 Nesbit Road, Mumbai 400 010, INDIA http://www.teappcm.com/products/general.htm#Sseries

Other Possible Sources Dupont http://www2.dupont.com/Energain/en_GB/products/index.html

BASF - PCM http://www.micronal.de

30

Appendix C. “Local Living Economies”

Local Living Economies are economic systems that prioritize human and community needs and interests by providing local resources, fair wages, and low environmental impacts.

Author and activist David Korten writes, “Local Living Economies are made up of human-scale enterprises locally owned by people who have a direct stake in the many impacts associated with the enterprise.”

It is noted that a business owned by workers, community members, customers, and/or suppliers who directly bear the consequences of its actions is more likely to provide workers with safe, meaningful, family-wage jobs; to produce useful, safe, high-quality products; to encourage local investment, stable markets and fair prices for suppliers and consumers; and to promote the trust and responsibility required for a healthy and sustainable social and natural environment.

31

Appendix D: Other References of Possible Interest

Bernier, U.R., "Mass Spectrometric Investigation of Mosquito Attraction to

Human Skin Emanations", Ph.D. Thesis presented at the University of Florida, Published by UMI Dissertation Services, Ann Arbor, MI, 1-333 p., (1995).

Braks, M.A., et al., "Incubated Human Sweat But Not Fresh Sweat Attracts the Malaria Mosquito Anopheles gambiae Sensu Stricto", Journal of Chemical Ecology, 25 (3), 663-672, (1999).

Carlson, D.A., et al., "Carbon Dioxide Released from Human skin: Effect of Temperature and Insect Repellents", Journal of Medical Entomology, 29 (2), 165-170, (1992).

Charlwood, J.D., et al., "Mosquito-Mediated Attraction of Female European but not African Mosquitoes to Hosts", Annals of Tropical Medicine and Parasitology, 89 (3), 327-329, (1995).

De Jong, R., et al., "Olfactory Responses of Host-Seeking Anopheles gambiae s.s. Giles (Diptera: Culicidae)", Acta Tropica, 59, 333-335, (1995).

De Jong, R., et al., "Selection of Biting Sites on Man by Two Malaria Mosquito Species", Experentia 51, 80-84, (1995).

Eiras, A.E., et al., "Host Location by Aedes aegypti (Diptera: Culicidae): a Wind Tunnel Study of Chemical Cues", Bulletin of Entomological Research, 81, 151-160, (1991).

Eiras, A.E., et al., "Responses of Female Aedes aegypti (Diptera: Culicidae) to Host Odours and Convection Currents Using an Olfactometer Bioassay", Bulletin of Entomological Research, 84, 207-211, (1994).

Geier, M., et al., "A search for components in Human Body Odour that Attract Females of Aedes Aegypti", Ciba Foundation Symposium 200 on Olfaction in Mosquito-Host Interactions, 132-148, (1996).

Kline, D.L., "Olfactory Responses and Field Attraction of Mosquitoes to Volatiles from Limburger Cheese and Human Foot Odor", Journal of Vector Ecology, 23 (2), 186-194, (Dec. 1998).

32

Mboera, L.E., et al., "Olfactory Responses of Female Culex quinquefasciatus Say (Diptera: Culicidae) in a Dual-Choice Olfactometer", Journal of Vector Ecology, 23 (2), 107-113, (Dec. 1998).

McCall, P.J., et al., "Attraction and Trapping of Aedes aegypti (Diptera: Culicidae) with Host Odors in the Laboratory", Journal of Medical Entomology, 33 (1), 177-179 (1996).

Mihok et al., `Trials of traps and attractants for Stomoxys spp. (Diptera: Muscidae` (Journal of Medical Entomology, (1995) vol. 32, No. 3, pp. 283-289), STN/CAS online, file BIOSIS, Abstract.*

Posey, K.H., et al., "Triple Cage Olfactometer for Evaluating Mosquito (Diptera: Culicidae) Attraction Responses", Journal of Medical Entomology, 35 (3), 330-334, (1998).

Price, G.D., et al., "The Attraction of Female Mosquitoes (Anopheles quadrimaculatus SAY) to Stored Human Emanations in Conjuction with Adjusted Levels of Relative Humidity, Temperature, and Carbon Dioxide", Journal of Chemical Ecology, 5 (3), 383-395, (1979).

Schreck, C.E., et al., "A Material Isolated from Human Hands that Attracts Female Mosquitoes", Journal of Chemical Ecology, 8 (2), 429-438, (1981).

Schreck, C.E., et al., "Mosquito Attraction to Substances from the Skin of Different Humans", Journal of the American Mosquito Control Association, 6 (3), 406-410, (Sep. 1990).

Smith et al., L-lactic acid as a factor in the attraction of Aedes aegyptic (Diptera:Culicidae) to human hosts, Ann. Entomol. Soc. Amer. (1970), vol. 63, No. 3, pp. 760-770.

Takken, W., "The Role of Olfaction in Host-Seeking of Mosquitoes: A Review", Insect Sci. Applic., 12 (1/2/3), 187-294, (1991).

Takken, W., et al., "Odor-Mediated Behavior of Afrotropical Malaria Mosquitoes", Annu. Rev. Entomol., 44, 131-157, (1999).

Takken, W., et al., "Odor-Mediated Flight Behavior of Anopheles gambiae Giles Sensu Stricto and An. stephensi Liston in Response to Carbon Dioxide, Acetone, and 1-Octen-3-ol (Diptera: Culicidae)", Journal of Insect Behavior, 10 (3), 395-407, (May 1997).

Van Essen, P.H., et al., "Differential Responses of Aedes and Culex Mosquitoes to Octenol or Light in Combination with Carbon Dioxide in Queensland, Australia", Medical and Veterinary Entomology, 63-67, (1993).

33

Wensler, R.J., "The Effect of Odors on the Behavior of Adult Aedes aegypti and Some Factors Limiting Responsiveness", Can. J. Zool., 50, 415-420, (1972).

Willis, E.R., et al., "Reactions of Aedes Aegypti (L.) to carbon Dioxide", J. Exp. Zool., 121, 149-179, (1952).