Cockroaches have long been known for their resilience, even in Burlington, surviving weeks without food and withstanding the radiation from nuclear blasts. But now, much to the disdain of the squeamish, the world’s most hated pests are evolving to withstand the insecticides that are designed to kill them.
Researchers have found that certain species of cockroach are developing cross-resistance to almost every kind of chemical insecticide used by exterminators, bringing them closer to invincibility.
“This is a previously unrealized challenge in cockroaches” says Jim Miner at www.burlingtonpestcontrol.ca
“Cockroaches developing resistance to multiple classes of insecticide at once will make controlling these pests almost impossible with chemicals alone”.
Worse yet, Miner says the problem is especially prevalent in urban areas and low-income or provincially subsidized housing where resources to effectively combat cockroach infestations aren’t always available.
For the study, the effects of common insecticides on German cockroach populations, the most common species, were tested in apartment buildings over six months.
One group of insects was treated with a single insecticide and a second received two insecticides from different classes. The third group was treated with three different insecticides, one per month, for two three-month cycles.
Researchers found that rotating pesticides was “mostly ineffective” at reducing roach populations because a certain percentage of the creatures developed a cross-resistance. Cockroaches that survived the dosing and their offspring, were found to be “essentially immune” to that insecticide going forward. But they also gained resistance to other varieties of pesticides, even if they hadn’t been exposed to them.
Adding to the problem is the pace at which cockroaches reproduce.
Female cockroaches have a three-month reproductive cycle during which they can have up to 50 offspring. According to the study, even if a small percentage of roaches became resistant, a population knocked down by a single dose could be quickly repopulated.
At www.burlingtonpestcontrol.ca we are studying and using the most advance method to overcome this problem.