Louisa Richards of The London School of Hygiene and Tropical Medicine observed increasing numbers of enquiries about bed bugs in the USA, Canada and Australia and reported that, in London, there is a current increase at a rate of 25% per year. A model has been devised which can be used to predict future trends and monitor control. [emphasis added]

Cool.

(Bonus: there’s also a table with the results of Richard Naylor’s laundering study which Fedup shared before but we’ve been unable to link to.)

You know, this is what Clive Boase wrote in 2001:

On a broad level, this outbreak raises fundamental questions about pest outbreaks. We know very little about the underlying biological and mathematical mechanisms that within a few years, can push a previously uncommon urban pest into a widespread outbreak. Only by understanding those processes can we hope in the future to forecast outbreaks of urban pests and vectors, and to design evidence-based strategies that will effectively interrupt such outbreaks.

He then outlines three critical factors:

Firstly, there is an urgent need for a monitoring tool that would enable infestations to be identified rapidly, so that they can then be eliminated before they disperse and so extend the outbreak. […]

Secondly, there is a similar urgent need for information on the current susceptibility status of bedbugs, to enable the most effective products to be identified. […]

Lastly, responsibility for record keeping on urban pests needs in some way to be consolidated, so that quantitative information is readily available to justify the need for appropriate action. However, with national and international responsibility for public health pests becoming fragmented between a range of private and public sector organisations, the chances of this happening appear to be increasingly remote.

“Bed bugs - back from the brink,” Pesticide Outlook. (Link is a PDF.)

And we wait. There’s work being done but so far very little progress on #1, some progress (although it’s hard to call it progress when the results are so discouraging) on #2 and, as expected, nothing on #3 — I think; I actually did see mention of a trend model being devised, somewhere.

I simply love Boase’s writing. That article is great. (Lots to think about, and mentions a 19th century bedbug trap that’s interesting as a possible monitoring tool in these grim times, and also mentions the increase of infestations in other countries as well.) In fact, for the following alone, on the theories for the resurgence, I am forever grateful:

Although various hypotheses for this increase have been proposed, none has yet been substantiated.

Sounds very different from what we hear others say, right, all those who confidently recite all the “causes” starting with the one with the letter i?

Then, in his 2004 article in Biologist (also a PDF), he outlines a simple epidemiological progression that is one of the most compelling things I’ve read about our difficult problem:

A + B - C = D

A: number of infestations at the start of the year
B: number of new infestations
C: number of infestations eliminated
D: total number infestations at the end of the year

Sorry to go on but these two articles are so rich.

Blimey, 7771 cases in the UK in 1985-86? That explains why I saw sealed mattresses in Britain in the late 1980s. (Sealed as in your aunt’s 1960’s sealed in plastic sofa–when you could never figure out why she did such a crazy thing? Well, now you know!)

Here is something to chew on.

The Toronto study of 2003 surveyed 89% of the city’s PCOs and found there were 847 locations treated by those PCOs. 2003 is well into the resurgence, yes? Can’t be the whole picture by any means, right?

How about: there were 7771 locations in England and Wales treated in a one-year period.

What year? 1985-1986!

Who kept such careful records? The Institution of Environmental Health Officers.

1986-1987? 6179 premises.

Source: King, F; Dick, I; Evans, P . “Bed bugs in Britain.” Parasitology Today Vol. 5, no. 4, pp. 100-102. 1989.

Bed bugs (Cimex lectularius L.) still abound in some areas of the UK.

Two thoughts:

1) Resurgence shmsurgence.
2) If only we had such data! Not just historically, but now.