When we heard that the the New York City Housing Authority’s Chief Exterminator estimates that 70% of bed bug reports are “actual” infestations, that 70% resonated.

I just remembered where we heard 70% before.

In an interview with Pest Management Professional, medical entomologist Dr. Jerome Goddard said that his review of the research indicated that 70% of people do not react to bed bug bites. (You can listen to the interview here: Pest Control Presents #23 – 10 Questions With Jerome Goddard, state medical entomologist for Mississippi.)

When people don’t have an allergic reaction to bed bug bites, it can take a very long time for them to become aware of an infestation. They may only become aware of it when the signs of infestation are obvious, after the infestation has grown and possibly spread to multiple rooms. The only good thing about an obvious infestation is that it’s, er, obvious, and there’s no convincing of landlords and inspectors to be done. Bed bugs are crawling about in plain sight.

So that 70% figure is bad news.

People who are allergic may suspect bed bugs quite soon after they are introduced to a home, but may still not find signs of the infestation. Finding a small number of bed bugs can challenge the skills of the most experienced pest control professionals.

In NYCHA’s bed bugs fact sheet for public housing residents, right at the top, it says:

They only come out at night, and they can be hard to detect, but once you have them you will need a NYCHA exterminator to get rid of them.

Let’s take note. Bed bugs can be hard to detect. Public housing residents call a Centralized Call Center or their management office, not the city’s 311 line, to have their apartments treated. They need not prove they have bed bugs in an adversarial system of complaints and violations.

We think it’s significant that at least 70% of them are found not to be mistaken or, worse, as has been suggested, delusional. They have bed bugs. It is also evident that NYCHA does not track bed bug reports versus “actual” infestations. The two numbers are not tracked separately as they are for private residential tenants by the city’s Department of Housing Preservation and Development (HPD). As Persona and Mangy have suggested in the comments, we will have to look into the reasons for the gap between bed bug complaints called in to the city’s 311 line by private residential tenants and the resulting number of HPD-issued landlord violations.

Because, if bed bugs are hard to detect, what exactly is the process of detection?