Global drivers of human pathogen richness and prevalence

Abstract

The differences in the richness and prevalence of human pathogens among different geographical locations have ramifying consequences for societies and individuals. The relative contributions of different factors to these patterns, however, have not been fully resolved. We conduct a global analysis of the relative influence of climate, alternative host diversity and spending on disease prevention on modern patterns in the richness and prevalence of human pathogens. Pathogen richness (number of kinds) is largely explained by the number of birds and mammal species in a region. The most diverse countries with respect to birds and mammals are also the most diverse with respect to pathogens. Importantly, for human health, the prevalence of key human pathogens (number of cases) is strongly influenced by disease control efforts. As a consequence, even where disease richness is high, we might still control prevalence, particularly if we spend money in those regions where current spending is low, prevalence is high and populations are large.

Parasite stress promotes homicide and child maltreatment

“…There is convincing evidence that public-health expenditures that target infectious diseases actually reduce greatly the severity of the diseases in general (i.e. reduce the number of cases of the diseases) [27]. The parasite-stress theory of values predicts that homicide rates would begin to decline after one generation (about 20 years) and continue to decline in successive generations.…”

“…Parasite stress varies consistently and strongly with climate and its surrogate, latitude. Hot and wet areas or low latitudes consistently have the highest parasite stress [4,5,[24][25][26][27].…”

Global biogeographic regions in a human‐dominated world: the case of human diseases

“…In addition, we used derived estimates of human population density (persons per square kilometer in 2010), gross domestic product (2012 US dollars), and land area (square kilometer) data per country from the Population Division of United Nations (United Nations 2013) and supplemented as needed from the CIA World Factbook (http://www.cia.gov). Human population density has the potential to influence the persistence of pathogens, but it has been suggested that there is also an association between the diversity of human pathogens and the diversity of birds and mammals, with areas with higher diversity of birds and mammals tending to have more diseases caused by pathogens (Dunn et al 2010). For our analyses we chose to use only native mammal species richness data since global bird, mammal, and plant richness are highly correlated (Qian and Ricklefs 2008), and our qualitative result should be similar regardless of which of these variables we analyze.…”

Spatial pattern of adaptive and neutral genetic diversity across different biomes in the lesser anteater (Tamandua tetradactyla)

“…Thus, parasite/pathogen diversity and pressure along distinct environments should be higher in moister areas harboring higher host species richness (Dunn et al. 2010). …”