QUESTION:
Having been involved with bed bug control for 15 years I have seen many changes in methodology and pesticides as well as non-pesticide treatments. There are two products that I use often, Steri-fab and Bedlam. I used to time how long it takes to kill the bed bug and it USED TO BE within 27 to 32 seconds. Now I watch more than a minute before the kill takes place, and sometimes even that doesn’t occur. Have there been any reports on resistance being built up by the bed bugs?
ANSWER:
The news since The Common Bed Bug came back into our lives has been just abuzz with information on the resistance to insecticides that is clearly taking place. While I do not recall the exact numbers, Dr. Dini Miller of Virginia Polytech Univ. recently did studies to test the levels of resistance, and she came up with surprising and frightening numbers showing that many commonly used active ingredients took from many hours to many DAYS of continuous exposure between the bed bug and the active ingredient to cause the final death of the bugs. In some cases, and perhaps an increasing percentage of them, bed bugs today are 1000 times more resistant to insecticides than they were decades ago. All of our industry leaders and research experts advise us that pesticides alone are not likely to control a dug-in bed bug problem. You need to be incorporating other options as well.
Steri-Fab is 98% isopropyl alcohol with a very small amount of a pyrethroid in it, and Bedlam is, I believe, also primarily alcohol with a light level of syngergized pyrethroid in it. You would think that the alcohol portion would just fry bed bugs and their eggs on contact, but this does not seem to occur, although direct contact with eggs and bugs does seem to do a good job. Many companies add liquid pyrethrum to their residual for application, and this seems to help with knockdown and ultimate kill. Perhaps it is the pyrethrum or perhaps it is the synergist in the pyrethrum that does the trick in moving things along. Many other products are also used by PMP’s with what they claim is great success, so insecticides definitely do kill bed bugs, but just much more slowly than they used to, and the ability for bed bugs to build up resistance to active ingredients seems very clear.
Hopefully your bed bug control procedure also involves those other accepted steps – heating by laundering and drying, dry cleaning, the use of heat chambers when needed, the use of sealed chambers with vapona strips for electronics, the installation of encasements for beds, the use of vacuum and/or steamer for many sites around the infested rooms. Resistance definitely exists and it is unlikely that some new magical insecticide product is going to come to our market anytime soon. The unbelievable cost to manufacturers to develop new active ingredients really prohibits their ability to come up with a new one just for this specific pest problem.
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