Plasmodium vivax is endemic to many areas of Afghanistan. Geographic analysis helped highlight areas of malaria risk and clarified ecologic risk factors for transmission. Remote sensing enabled development of a risk map, thereby providing a valuable tool to help guide malaria control strategies.

In this issue, Robinson’s highly influential paper is reprinted, along with a paper advocating the use of multi-level thinking by Subramanian et al., and commentaries by Oakes and Firebaugh. On re-reading Robinson’s paper, I was again struck by the clarity of the basic take-home message: ecological data can estimate individual associations in only very rare situations. Robinson illustrated the ...

The ecologic study design is routinely used by epidemiologists in spite of its limitations. It is presently unknown how well the challenges of the design are dealt with in epidemiologic research. The purpose of this bibliometric review was to critically evaluate the characteristics, statistical methods, and reporting of results of modern cross-sectional ecologic papers. A search through 6 major...

To the Editors: The recent article reporting no association of consumption of animal foods with risk of ovarian cancer (1) was based on an incomplete study (2). Whereas ecologic studies can find animal products as an important risk factor for breast cancer (2, 3), a more recent ecologic study based on ovarian cancer mortality rates for European countries for 1989 to 1991 and dietary data for th...

BACKGROUND Radon, a naturally occurring radioactive gas, is a carcinogen that causes a small proportion of lung cancers among exposed populations. Theoretical models suggest that radon may also be a risk factor for skin cancer, but epidemiologic evidence for this relationship is weak. In this study, we investigated ecologic associations between environmental radon concentration and the incidenc...

BACKGROUND Blastomycosis is a potentially fatal mycosis that is acquired by inhaling infectious spores of Blastomyces dermatitidis present in the environment. The ecology of this pathogen is poorly understood, in part because it has been extremely difficult to identify the niche(s) it occupies based on culture isolation of the organism from environmental samples. METHODOLOGY/PRINCIPAL FINDING...

BACKGROUND In Orebro County, Sweden, a 2.5-fold increase in the incidence of Haemophilus influenzae (HI) meningitis was found between 1970 and 1980. In a case-control study of possible risk factors for invasive HI infection conducted in the same area, 1987-1992, breastfeeding was found to be a strong protective factor. MATERIAL AND METHODS In order to study the relation between incidence rate...

Impact of van-comycin resistance on mortality among patients with neutropenia and enterococcal bloodstream infection. Epidemiology and mortality risk of vanco-mycin-resistant enterococcal bloodstream infections .terococcal bacteremia: risk factors for vanco-mycin resistance and predictors of mortality.tant and vancomycin-susceptible enterococcal bacteremia: comparison of clinical features and o...

We introduce a symbolic representation like set theory to consider ecologic interactions between species (ECOSET). The ecologic exclusion principle (Gause) is put in a symbolic way and used as operational tool to consider more complex cases like interaction with sterile species (SIT technique), two species with two superposed sources (niche differentiation) and N+P species competing by N resour...