What do we know about the easing of malaria burdens?

There are some new and interesting results from Lena Huldén, Ross McKitrick and Larry Huldén.  Here is the abstract:

Malaria has disappeared in some countries but not others, and an explanation for the eradication pattern has been elusive. We show that the probability of malaria eradication jumps sharply when average household size in a country drops below four persons. Part of the effect commonly attributed to income growth is likely due to declining household size. The effect of DDT usage is difficult to isolate but we only identify a weak role for it. Warmer temperatures are not associated with increased malaria prevalence. We propose that household size matters because malaria is transmitted indoors at night, so the fewer people are sleeping in the same room, the lower the probability of transmission of the parasite to a new victim. We test this hypothesis by contrasting malaria incidence with dengue fever, another mosquito-borne illness spread mainly by daytime outdoor contact.

The gated published version is here.  A six-page author summary is here.

For pointers I thank Aaron C. Chmielewski and Gregory Rehmke.