Tag Archives: experiment

Experiment shows Spartan Mosquito Eradicator do not work

Experiments on Spartan Mosquito Eradicators fail to detect efficacy

According to research conducted in Florida, there’s no evidence that Spartan Mosquito Eradicators kill mosquitoes. Here’s the citation:

Aryaprema, V.S., E. Zeszutko, C. Cunningham, E.I.M. Khater, and R.-D. Xue. 2020. Efficacy of commercial toxic sugar bait station (ATSB) against Aedes albopictus. J. Florida Mosquito Control Association 67: 80-83. PDF

I summarize the two experiments and explore some of the implications, below.

Laboratory experiment

Below is a rough reconstruction of the laboratory experiment they conducted. In each of the cages (BugDorm-2120), 100 male and 100 female tiger mosquitoes (Aedes albopictus) were released, then monitored for mortality at 24, 48, and 72 hours.

Schematic of laboratory experiment based on description in Aryaprema et al. 2020.

Below are the cumulative mortality data for the three cages. Result: the Spartan Mosquito Eradicator filled with the provided packet ingredients (treatment) did not result in higher mortality. I.e., there was no evidence the device killed mosquitoes under laboratory conditions.

Field experiment

The researchers also conducted a field experiment using two sites that had large populations of tiger mosquitoes (because of the presence of tires). At each site they deployed five tubes (separated by 4 m), switching whether the tubes were “treatment” or “control” tubes every 2 weeks. A BG-Sentinel trap (without carbon dioxide) was used to quantify mosquito numbers every week.

Schematic of field experiment based on description in Aryaprema et al. 2020.

Below are the weekly numbers of mosquitoes caught in the BG Sentinel traps. Results: there was no evidence that presence of treatment tubes (filled as per company guidelines) reduced the numbers of mosquitoes at the sites.

Conclusions

Their overall conclusion: “Both laboratory and field components of our study show that the Spartan Mosquito Eradicator is not effective in reducing abundance of Ae. albopictus.” They speculate that the contents do not attract mosquitoes and that the holes on the device (~3 mm) are too small for mosquitoes to easily reach the fluid inside. They also highlight the need for an experiment to evaluate whether the active ingredient (1% sodium chloride) kills adult mosquitoes. I.e., even if mosquitoes were attracted to Spartan Mosquito Eradicators and could easily get inside, the salt might not be lethal. Per unpublished research, a 1% salt solution is, in fact, not lethal to adult mosquitoes.

Implications

The results of the experiments call into question the efficacy claims made by the owners of Spartan Mosquito. For example, the company says on the box that a 95% reduction in mosquitoes will occur within 15 days and will last for three months. The company also prints a graph on the label that indicates almost 99% of mosquitoes are killed by the end of this period.

Spartan Mosquito Eradicator efficacy graph

If the claims are false or misleading, which seems to be the case, states can classify the device as “misbranded” and issue stop-sell orders. Some have already done so.

These findings will also be important for the class-action suit that has been filed against the company and its owners. I.e., because there is now peer-reviewed evidence that the device does not kill mosquitoes, it will be considerably easier to prove to a jury that the company’s efficacy claims are false or misleading.

Finally, the results call into question the efficacy claims of the company’s newest product, the Spartan Mosquito Pro Tech, which replaces sodium chloride with boric acid. Although a boric acid solution can certainly be lethal if mosquitoes ingest it, the Pro Tech is based on the same design as the Eradicator and thus would not be expected to either attract mosquitoes or to allow them easy access to the fluid inside. The Pro Tech label, however, asserts that the device will attract and kill mosquitoes. It would be great to get a third-party assessment of whether those label claims are true.

Testing the Eradicator and Pro Tech at home

In regards to the question of attractiveness to mosquitoes, consumers can easily assess that at home with a zoom-equipped camera, binoculars, or a security camera. The idea is to be able to see mosquitoes near the cap (if they are there) but to be far enough away so as not to distract the mosquitoes. Ideally, capture a photograph or movie and get confirmation of what insects are actually gathering around the device (again, if any).

Per the above paper, you likely won’t see mosquitoes gathering around the devices. Per the company, mosquitoes will gather around the devices.

People can also assess whether mosquitoes are entering the devices by dumping the contents onto a white plate and taking a photograph. Ideally, share your photographs on Spartan Mosquito’s Facebook page — they’d love to see them. Or post on them on Twitter and cc me (@colinpurrington).

Spartan Mosquito Pro Tech

Here’s an early look at the Spartan Mosquito Pro Tech, the newest device made by the makers of the wildly popular Spartan Mosquito Eradicator, which I reviewed in 2019.

What is the Spartan Mosquito Pro Tech?

Aside from differences in label design, the Pro Tech looks just like the Eradicator — a plastic tube fitted with a cap that has several ~11/64″ holes and a hook for hanging. And it’s filled with essentially the same ingredients (water, sugar, yeast). The big difference appears to be that the active ingredient is now boric acid instead of sodium chloride.

Per the labelling, the major differences are that the Pro Tech (1) works for 30 days instead of 90 and (2) “kills mosquitoes” instead of killing 95% of them.

The name, “Pro Tech”, is presumably to signify to consumers that the device is “professional technology”. This name is line with company’s description of the Pro Tech as “next-generation” and “most advanced“.

How does the Pro Tech kill mosquitoes?

The company asserts the following occur:

  1. mosquitoes are attracted to the tubes
  2. mosquitoes land on the tubes
  3. mosquitoes crawl around until they find the 11/64″ holes in the cap
  4. mosquitoes squeeze though the holes
  5. mosquitoes walk down sides of tube toward liquid
  6. mosquitoes ingest some of the liquid
  7. mosquitoes walk back up sides of tube
  8. mosquitoes find holes
  9. mosquitoes squeeze through holes
  10. mosquitoes fly away
  11. mosquitoes die from boric acid poisoning

A typical yard might have thousands of mosquitoes, so at any one time there might be a cloud of mosquitoes gathered around the devices, at least according to the company’s advertising. I have not been able to find a photograph that shows a cloud of mosquitoes around a Pro Tech.

Do Pro Techs kill mosquitoes?

The more important question is, “Does the Pro Tech kill mosquitoes in a yard?” The rephrasing of the question is important because a loophole in the EPA guidelines allows a company to claim a device kills an outdoor pest even if the efficacy experiment was done indoors. I’m not sure whether this is the case with the Spartan Mosquito Pro Tech, but it’s a concern. Laboratory experiments of attractive toxic sugar bait (ATSB) devices could easily overestimate actual efficacy for several reasons.

One worry is that boric acid can enter the vapor state. This means that mosquitoes trapped inside net cages with Pro Techs would be expected to die at a faster rate simply because boric acid is present in the air inside the cage, not because any of the mosquitoes actually squeezed through holes in the caps and ingested the liquid. Another huge problem is that when ATSB devices are tested inside cages, mosquitoes have no choice but to seek out the sugar inside the devices. So one might see mosquitoes entering the small holes of a Pro Tech inside cages even though mosquitoes in the real world would rarely do so. Under no circumstances would I recommend the EPA accept data from laboratory tests of ATSBs.

I’m not aware of any third-party evaluations of the Spartan Mosquito Pro Tech, but given that the Spartan Mosquito Eradicator does not work, it seems unlikely that the Pro Tech would work. I’ll update this page when peer-reviewed data are published.

Disclosures

Spartan Mosquito is suing me.

Shaving your legs to deter ticks

People shave their legs for a variety of reasons: to look younger, to look less like men, to show off tattoos, to show off muscle definition, to improve athletic performance, to facilitate post-accident wound cleaning (cyclists), and, apparently, to get a pleasurable sensory overload when wearing clothing. But can shaving also protect you from ticks?

I became curious this week after watching this dog tick (Dermacentor variabilis) crawl up my leg:

Here are some reasons why I think shaving would protect from ticks:

  1. Ticks can grip hair, so if you are hairless they can’t climb as fast.
  2. If you have hairless legs you can most likely better feel them crawling up your leg.
  3. When you remove all your leg hair you are removing a lot of sensory distractions caused by wind (experiment on swimmers) and thus you can zero in on things crawling on you.
  4. Without hair, small ticks are much easier to spot. Also easier for others to spot, in case people are ogling your legs.

No experiments on this topic have been done, but I found three relevant snippets on the internet:

  • “One thing that helps is shaving your legs. Not a foolproof way but I would say it reduces them critters by 80%, maybe more. I noticed that when my wife and I were out and she had none, I had around 14 that day.” source
  • “As an experiment I shaved my legs before riding point to point at lbl with KRS and a few others. It was tick season. After 40+ miles of riding I had 1 tick on my sock. Along the way KRS pulled OVER 15 ticks. We rode the same route at the same pace. I’ve kept the hair off ever since.”  source
  • “I’d say its mostly impractical. Although, I know many trail runners (including myself sometimes in the summer) do it to prevent ticks from attaching.” source

One experiment that needs to be done is to count the numbers of ticks on a group of people out for a walk, some of whom shave. But at least in the United States, that would break down to men versus women, and males smell worse than women and thus might attract more ticks, regardless of hirsuteness. And men are usually larger, so there’s the surface area thing that goes against guys, too. So it would be far better to recruit a group of hairy-legged people and ask them to shave just one leg, then march around a field known to have ticks. An ideal group for this experiment might be a men’s swim team right before the season begins. I.e., they all have hairy legs but will likely shave them for the season … so they won’t care. Would be crazy photogenic and fun. Plus great team-building exercise. Would get the college on the evening news I’m sure.

A simpler design might be to just have a motivated group of people (perhaps students in a field ecology course?) conduct tick races on shaved vs unshaved legs. You just need to start them on the ankles and have participants hold still while the ticks make their ascents. That would be equally photogenic and fun, I think.

If somebody does go ahead and conducts this experiment, the next step would be get the CDC to add a shaving recommendation to their tick page. The reaction to that would be really entertaining.