When addressing multi family apartments it is imperative that all suites surrounding an infested suite are, at minimum, inspected for bed bugs. Most exterminators will suggest treating all surrounding suites as a precaution. Some exterminators will only treat the baseboards if a suite is adjacent to an infested suite but shows no evidence of bed bugs. What is the correct protocol?
8 years ago in Winnipeg the issue of pesticide resistance was very small. The exterminator could treat a baseboard with Permethrin and as the bugs came out of the walls they would contact the residual and die within a few feet of the baseboard. Dead bugs would be found everywhere. These days I rarely find dead bugs and the issue of resistance is escalating exponentially. In the last year I have noted an increasing number of bugs that are able to harbor, seemingly without adverse effect, on treated surfaces. In other cases I treat the area under the bed with residuals and the traps under the bed legs contain many live bed bugs suggesting they survived crossing the residuals. This is now the new normal in Winnipeg.
If the bugs can cross several feet of a surface treated with a residual and, sometimes, be found harboring on treated surfaces, what is the point of precautionary treatments of neighboring baseboards? There is no point. It is a waste of time.
A full treatment of surrounding suites would be helpful but this causes a great deal of hardship for the tenants who may or may not even have bed bugs. I find that as long as the exterminator does not overapply chemicals, the tenant does not self treat or drag his/her mattress, and the infestation is discovered before it becomes a huge problem, the bugs remain only in the one suite. Multiple infestations are a problem in a minority of cases. Therefore the majority of suites surrounding an infestation do not need treatment. As such I recommend closely monitoring all surrounding suites and treating only those that have bed bugs. I also recommend that tenants be educated about the problems inherent in the self treatment of bed bugs to minimize unnecessary spread. Prevention is always better than treatment.