Entomology Without Borders

Editor’s Note: The following article appeared on Mike Merchant’s blog, “Insects in the City,” which can be found at insectsinthecity.blogspot.com. The blog offers readers news and commentary about the urban pest management industry and is excerpted here with permission of the author.

If you can imagine thousands of entomologists swarming a convention center like fire ants on Cheetos, that’s what it was like at the 25^th International Congress of Entomology (ICE), at the Orange County Convention Center in Orlando, Fla., in late September 2016. Held every three years, and rotating to a different nation every time, ICE is the largest gathering of professional insect experts in the world — and the most recent conference may have been the biggest ever. This event had more than 6,600 registrants from 102 countries, giving 5,396 presentations.

So here are some highlights of my notes from the many hours of sitting in sessions and looking at PowerPoint slides:

German cockroach resistance to baits was the subject of a paper by North Carolina State University researcher Jules Silverman. When comparing a susceptible German cockroach strain versus a field strain from Puerto Rico, his team found resistance to fipronil (15-20X), indoxacarb (15,000X) and even hydramethylnon (350X). This was the first time hydramethylnon physiological resistance (as opposed to avoidance) has been found. Even with this resistance, in the lab researchers still saw complete control of cockroaches with gel baits. But control was not as good in field trials where cockroaches had access to other foods. My take-home message was that we must be careful in our use of cockroach baits, and use them in combination with sanitation, sprays and other control tactics if we want to preserve them for coming years.

Dr. Paula Stigler Granados from the University of Texas School of Public Health reported on the status of Chagas disease in the U.S. Granados leads a task force studying the best way to protect human health from this disease transmitted by kissing bugs. Doctors tend to downplay the risk of Chagas disease and rarely test for the disease. Blood banks only test for Chagas if a person is a first-time donor; hence some are concerned about the possibility of our U.S. blood supply becoming contaminated with the Chagas disease parasite. It’s estimated that as many as 98 to 99 percent of cases in the U.S. remain undiagnosed.

Educational awareness among doctors and patients will be a focus of the Texas Chagas task force, along with better screening, diagnosis and treatment. Chagas is a chronic and ultimately fatal disease. In previous years it was considered untreatable; but with a new drug therapy it now can be treated in earlier stages. Getting the drug to people who need it is still a challenge, however.

In related papers, Dr. Gabe Hamer from Texas A&M reported on the results of a citizen science effort to study kissing bugs. From 2013 to 2015, they collected 2,812 bugs from 98 different Texas counties. The most common species detected was Triatoma gerstaeckeri, with 63 percent of those collected infected with the Chagas disease pathogen. Another study by Rodion Gorchakov from the Baylor College of Medicine in Houston showed that humans are the most common host for kissing bugs collected by citizen scientists in Texas with human blood found in 66 percent of bugs. So why not more Chagas disease in Texas and other parts of the U.S.? The theory is that T. gerstaeckeri and other native kissing bug species are not very good at transmitting the disease during biting.

A couple of the more interesting and fun talks I attended were on insects and Japanese art and culture. The pest management industry is familiar with Dr. Nan-Yao Su, developer of the Sentricon system concept at the University of Florida. Turns out he is interested in insect influences on Japanese culture. I was fascinated to learn from him the importance of insects to Japanese culture. This shows up in many places, from the popularity of insects as pets in Japan to the horns of the legendary samurai helmets, designed to resemble the revered kabutomushi, or Japanese rhinoceros beetle. And who can forget Mothra — the giant silkworm moth that symbolized the silk industry to the Japanese?

Gunter Miller, from Hebrew University in Jerusalem, Israel, spoke on the process of developing effective attractive toxic sugar baits (ATSBs) for mosquito control. Based on the fact that both male and female mosquitoes feed on natural sugar sources (like nectar and honeydew), ATSBs must be competitive with these natural sources, so the process of developing these baits is more complicated than just mixing sugar with a pesticide and spraying it on plants. Their lab developed a “mosquito sangria” mixture (includes beer and sangria) that will remain attractive to mosquitoes for more than a month after spraying. Their technology is being used in the Terminix All Clear Mosquito Bait Spray. This approach to mosquito control has attracted a lot of attention because of its potential to control some Aedes mosquitoes (vectors of Zika, and the most common daytime biters), and because of its need for less insecticide that might be harmful to beneficial insects.

Joel Coats from Iowa State University has been studying alternatives to PBO, the most commonly used synergist for pyrethrins and other pyrethroid insecticides. He found that many of the plant extracts he tested synergized permethrin as well or better than PBO, and many worked faster than PBO. Apparently PBO was developed early as a standard synergist for the industry, and few people have taken the time to look at alternatives over the past 50 years. Having an organic synergist could be a real market boost to pyrethrin sprays, most of which cannot be sold as organic because of the synthetic PBO needed to make it effective.

According to MacKenzie Kjeldgaard of Texas A&M University, who analyzed ant gut contents with sophisticated DNA techniques, the fire ant’s top food source was crickets, but also included springtails, caterpillars, flies and spiders.

Freder Medina introduced a new BASF termiticide injection system using Termidor H.E. The new application system uses 4,000 psi pressure to inject the insecticide into the ground, eliminating the need for drenching. The system comes with a base unit and mobile app to communicate with BASF.

Last, I had a pleasant surprise in the commercial exhibits when I discovered a bed bug book published by Stephen Doggett, University of Sydney, Australia. Doggett is a well-known bed bug researcher, but had the genius to put out a handy photographic guide to bed bug infestations. It has dozens of excellent photos, tells where and how to spot bed bugs, and what to do if bed bugs are found in a home. This should be a useful resource to share with customers, and as a training tool for employees. The book is self published, and not widely available, but you can get it at BioQuip books for about $7.

Of course, there was much more information at ICE this year, but space is limited so I’ll end there. I would highly recommend attending ICE should you have a passion for entomology and insects.

The author is an entomology specialist for Texas AgriLife Extension.