Do it yourself: 3D-printed miniature CDC trap for adult mosquito (Diptera: Culicidae) surveillance
Cite this dataset
Bibbs, Christopher (2024). Do it yourself: 3D-printed miniature CDC trap for adult mosquito (Diptera: Culicidae) surveillance [Dataset]. Dryad. https://doi.org/10.5061/dryad.x95x69prh
Abstract
The central component of mosquito and vector surveillance programs globally is the adult mosquito trap, which is intended to collect host-seeking mosquitoes. The miniature CDC trap is a widely distributed trap style in part due to its relative affordability and compact nature. Despite already being a simple trap, in-house production methods, such as 3D printing, could improve the accessibility of the CDC trap by eliminating some of the supply chain variables. We present here several trials with the Salt Lake City (SLC) trap, a three-dimensional (3D) printed trap design. Functional assessments were made on secondary components and found no statistically significant differences when comparing CO2 line height (above vs. below fan), battery types (sealed lead acid vs. USB battery pack), and trap body collection shape (funnel body vs. simple/straight body). The SLC trap was compared directly to a commercial equivalent, the ABC trap, with comparative assessment on species diversity and evenness in collections and found to be statistically equivalent on all metrics. Methods also detail an accompanying optional transport system for a pressurized CO2/regulator set-up, should a practitioner elect not to use dry ice. Our final design is presented here with the publicly published stereolithography (STL) files and a detailed outline of the transport container system. Alternative models are available for in-house manufacture of mosquito traps, and we contribute these designs in an effort to stimulate further growth in vector surveillance.
README: 3D_printed_cdc_trap_validation
https://doi.org/10.5061/dryad.x95x69prh
A prototype 3D printed trap design, referred to as the SLC trap, was developed from a variety of exploratory model tests. Field sites were selected from historical surveillance locations of the Salt Lake City Mosquito Abatement District (SLCMAD) in environments containing a mixture of wetlands and sagebrush. Pairwise tests were conducted with different supplies and components to optimize the base model SLC trap.
Description of the data and file structure
Trap_Development_data_DRYAD.xlsx
Airstone Height:
Positioning of the airstone for CO2 dispersal either above or below the downdraft fan. Data as aggregate mosquito collections for a 24 hr trap night per replicate using 1kg dry ice in a transport cooler and dispersed with a line to the trap body. Standard error of the mean included. Paired t-test results included.
Variables: Rep = replicate number; Airstone Height = height of airstone; Location = site ID for trap rotations; # Mosquitoes = pooled mosquito collection totals
Battery Type:
A 6v sealed lead acid battery vs. a multi-day lithium USB battery pack. Data as aggregate mosquito collections for a 24 hr trap night per replicate using 1kg dry ice in a transport cooler and dispersed with a line to the trap body. Standard error of the mean included. Paired t-test results included.
Variables: Rep = replicate number; Battery = 6v sealed lead acid battery or USB lithium battery pack; Location = site ID for trap rotations; # Mosquitoes = pooled mosquito collection totals
Funnel:
SLC trap body printed as either a funneled entry or a straight sided piece (traditional design). Data as aggregate mosquito collections for a 24 hr trap night per replicate using 1kg dry ice in a transport cooler and dispersed with a line to the trap body. Standard error of the mean included. Paired t-test results included.
Variables: Rep = replicate number; Trap Body = funneled collection body vs. simple/straight sided trap body; Location = site ID for trap rotations; # Mosquitoes = pooled mosquito collection totals
ABC v SLC:
Pilot version of SLC trap using high mounted airstone, 6v battery, and straight-sided trap body. Comparison to a commercial mimi-CDC trap model, the Clark Mosquito Control (Pacific Biologics) ABC trap. Data both as aggregate mosquito collections and species breakdown from 24 hr trap nights per replicate using 1kg dry ice in a transport cooler and dispersed with a line to the trap body. Standard error of the mean included.
Variables: Trap = designation for either the SLC custom trap, or the commercially available ABC trap; Location = site ID for trap rotations; # Mosquitoes = pooled mosquito collection totals; species name (Cx. pipiens, Cx. tarsalis, etc.) = proportion of total collections from the given species.
Supp Figs Preliminary Traps:
Prototypical trap models preceding the SLC trap model used in the airstone, battery type, funnel, and ABC v. SLC trap comparisons. A 3-piece base design developed using an entry funnel mounted to a computer case fan, then stacked with a second funnel for connecting a catch net; used for 3 trap designs: a 12-volt case fan (Tornado TD8038H, Vantec Thermal Technologies, Fremont, CA) and measured at 20-kph suction. A 6-volt case fan (Multifan S1 80mm, AC Infinity, Inc., City of Industry, CA) measuring at 12-kph suction was then used for two separate models: “Complex Airstone” containing a 5-mm mineral airstone (Jardin Stone, UXCell Co., Hong Kong, China) on the CO2 line (4-mm inner diameter standard aquarium tubing, Penn-Plax, inc., Hauppauge, NY) for dispersing a lure homogenously; and “Pore Dispersal” where the CO2 line was fitted directly to the fan. The Salt Lake City trap design as covered in the main manuscript. 3D-printed trap design shared by Mosquito Consulting Services based in New Zealand. Positive control of the ABC trap (Clarke Mosquito Control, St. Charles, IL). Comparison data with a minimum of 4 replicates each and using aggregate adult mosquito collections for a 24 hr trap night per replicate using 1kg dry ice in a transport cooler and dispersed with a line to the trap body. Standard error of the mean included.
Variables: Rep = replicate number; trap = designation for various prototypes as described above; Location = site ID for trap rotations; # Mosquitoes = pooled mosquito collection totals; species name (Cx. pipiens, Cx. tarsalis, etc.) = proportion of total collections from the given species.
n/a values are those in which the total pooled mosquito collection was known, but the species identifications for that trap on that night were not carried out. These are absent values for the species data, but the aggregate/pooled totals are still valid for analysis that does not require the species breakdown.
Trap_Development_supplement_DRYAD.xlsx
Figures, pictures, and labels to show what the test groups an the aforementioned pages looked like and summarize how they were used.
Sharing/Access information
This is a section for linking to other ways to access the data, and for linking to sources the data is derived from, if any.
Data was derived from the following sources:
- [PNTD-D-23-00712](DO IT YOURSELF: 3D-PRINTED MINIATURE CDC TRAP FOR ADULT MOSQUITO (DIPTERA: CULICIDAE) SURVEILLANCE)
Methods
A prototype trap design, referred to as the SLC trap, was developed from a variety of exploratory model tests that are found in supplemental figures (Suppl. Fig. 1). Essentially, the prototype is a 1-piece tubular trap body with a rain guard (Fig. 1A). A 6-volt variable speed motor (RF-500TB-14415-R-J/32, Nichibo Taiwan Corp., Taipei, Taiwan) was equipped with a 4-blade, 7.5-cm propeller (Item #3C078RSHC1, Thorgren Tool & Molding, Inc., Valparaiso, IN) and secured inside the trap body with #2 conduit hanger (#2 ACC Conduit Hanger, Halex/Scott Fetzer Co, Cleveland, OH). All trap models can be operated using 18-guage, Class 2 copper wire (16-strand dual conductor/182C-200SR, MaxBrite LED Lighting Tech LLC, San Jose, CA). All 3D-printed components were fabricated from PLA plastic filament extruded through a 0.6 mm nozzle with set temperature at 210 °C (410 °F) and 58 °C (136 °F) bed temperature. The comparison model was the Clarke (or Pacific Biologics, AUS) branded ABC trap, with the light removed (Clarke Mosquito Control, St. Charles, IL), which is primarily composed of polyethylene and PVC plastics to make a trap body and rain guard (Fig. 1B).
Trap Evaluation Scheme
Field sites were selected from historical surveillance locations of the Salt Lake City Mosquito Abatement District (SLCMAD) in environments containing a mixture of wetlands and sagebrush. Site 1 was closest to the Great Salt Lake and was composed of muddy shores and salt playas (Fig. 2). Site 1 was furthest removed from human influence and in the heart of shorebird and waterfowl habitats in wildlife sanctuary lands. Site 2 (Fig. 2) was in the fringes of alkaline mudflats encroached by the Great Salt Lake and composed of a mix of palustrine flood plains and salt desert shrublands that were adjacent to animal agricultural lands. Site 3 was the furthest north location (Fig. 2) and was in the freshwater overflow for nearby reservoirs. Site 3 was characterized by saline meadow seeps and saline wetlands and was well outside any human occupied areas. The majority of mosquitoes historically occupying these environments was split between Aedes dorsalis (Meigen) and Culex tarsalis Coquillett. For SLCMAD, Cx. tarsalis is a priority vector of West Nile virus. Lights have been previously shown to confound vector Culex sp. collections the same general eco-region, in addition to increasing non-target insect numbers (15). Therefore, all trap nights, regardless of model, excluded the use of a light source.
Surveillance was conducted with 1 kg dry ice according to Sriwichai et al. (5) for trials comparing the SLC trap to the commercial model ABC trap. For experiments that were done for comparing various trap modifications to the SLC trap, the CO2 source was from a regulated compressed cylinder at the rate of 250 ml/min. For all trials traps were set for 24 hrs and trap collections were counted and identified with a hybrid camera and microscopy set-up using ImageJ (16). Species identifications were keyed according to Darsie and Ward (17). Tests were conducted with different supplies and components to optimize the base model SLC trap. Pairwise comparisons were conducted for SLC trap modifications were conducted exclusively at site 1. Tests were conducted between: CO2 dispensed high or low on the trap body (8 replicates); 6-volt sealed lead-acid batteries (PS-6100 6v 12Ah, Power Sonic Co., San Diego, CA) and USB battery packs (PowerCore 20 100mAh, Anker Innovations Co., Ltd, Hunan, China) (10 replicates); a funneled housing option (Suppl. Fig. 2) (4 replicates). For comparison of the SLC trap to the commercial model ABC trap (positive control), tests were replicated 4 times each at sites 2 and 3 for a total of 8 comparison nights. Whether doing accessory tests or the positive control comparison, both traps were present at the same site but spaced at least 100 m apart. Additional minor tinkering was conducted for transport container types, comparing tool boxes, buckets, and metal ammo cans. These transport containers were investigated for optional use with a pressure regulated CO2 cylinder system (moot in the case of dry ice, which can be carried in a separate cooler).
Transport containers were selected based on size, ruggedness and long-term service potential (Suppl. Fig. 2, Suppl. Fig. 3). Although it is suitable to embed the battery and CO2 source in a toolbox or bucket (Suppl. Fig. 2), the desire for space efficiency and durability led to selection of a re-purposed metal ammunition can from military surplus (Fig. 3, Fig. 4) for operational use at SLCMAD. The resulting final surveillance trap and container design was specially built around using a pressure-regulated CO2 cylinder system.
SLCMAD chose to adopt a pressure-regulated CO2 cylinder system after the above trials were conducted on trap design. Cylinder regulators were modified with a complex series of small parts to feed the gas safely to a lower CO2 line attachment (Fig. 3). A “¼ in to #10-32 reducer” (4CQF-ENP-PKG, Clippard Instrument Laboratory, Inc., Cincinnati, OH) was reinforced with PTFE tape and attached directly to the lower regulator. Short coupling O-rings (11999-PKG, Clippard Instrument Laboratory, Inc., Cincinnati, OH) were seated on both sets of threads of a “#10-32 connector” (11999-PKG, Clippard Instrument Laboratory, Inc., Cincinnati, OH), which was then screwed into the reducer. The reducer starts with a “0.0075 in diameter air choke” (CD-C, Clippard Instrument Laboratory, Inc., Cincinnati, OH) that is fitted with a choke disk inside the curved (non-faceted) end of the piece, then screwed onto the remaining threads of another “¼ in to #10-32 reducer”. The faceted end of the air choke is finished by screwing in a “#10-32 to ¼ in ID hose fitting” (11752-1-PKG, Clippard Instrument Laboratory, Inc., Cincinnati, OH) (Fig. 3). The CO2 line extends off the lower choke assembly (Fig. 3) and attaches to the underside of a PA70 ammo can measuring 42 cm × 30.5 cm” × 15.9 cm (B643, 8-Cartridge, 60MM, HE, M888 for M224 Mortar, United States Military Surplus) with another brass “#10-32 to ¼ in ID hose fitting.”
For the transport container itself, the top side of the ammo can lid was fitted with a female push-to-connect piece (Airbrush Quick Release Coupling ⅛-in BSP, Point Zero Ltd., China) that receives the male end (Fig. 4) when traps are deployed. To brace the CO2 cylinder inside the ammo can, 7-8 cm wide thermoforming plastic sheet (Sekisui Kydex, Bloomsburg, PA) was softened with a heat gun and then molded around the cylinder (Suppl. Fig. 3). After cooling to form, the sheet was riveted inside the ammo can to create a holster for the cylinder (Suppl. Fig. 3). The opposite end of the ammo can interior was then reinforced with padding, in this case with duct tape strips, so as to pad the batteries and prevent contact with the battery terminals. (Suppl. Fig. 3). Once complete, the transport containers receive a 6v battery, filled CO2 cylinder, and associated trap with collection net (Fig. 4).