The phylogenetic range of bacterial and viral pathogens of vertebrates

Abstract

Many major human pathogens are multihost pathogens, able to infect other vertebrate species. Describing the general patterns of host–pathogen associations across pathogen taxa is therefore important to understand risk factors for human disease emergence. However, there is a lack of comprehensive curated databases for this purpose, with most previous efforts focusing on viruses. Here, we report the largest manually compiled host–pathogen association database, covering 2,595 bacteria and viruses infecting 2,656 vertebrate hosts. We also build a tree for host species using nine mitochondrial genes, giving a quantitative measure of the phylogenetic similarity of hosts. We find that the majority of bacteria and viruses are specialists infecting only a single host species, with bacteria having a significantly higher proportion of specialists compared to viruses. Conversely, multihost viruses have a more restricted host range than multihost bacteria. We perform multiple analyses of factors associated with pathogen richness per host species and the pathogen traits associated with greater host range and zoonotic potential. We show that factors previously identified as important for zoonotic potential in viruses—such as phylogenetic range, research effort, and being vector‐borne—are also predictive in bacteria. We find that the fraction of pathogens shared between two hosts decreases with the phylogenetic distance between them. Our results suggest that host phylogenetic similarity is the primary factor for host‐switching in pathogens.

SARS-CoV-2 spike protein predicted to form complexes with host receptor protein orthologues from a broad range of mammals

“…Coronaviruses, including SARS-CoV-2, are major multi-host pathogens and can infect a wide range of non-human animals [3][4][5]. SARS-CoV-2 is a member of the Betacoronavirus genus, which includes viruses that infect economically important livestock, including cows [6] and pigs [7], together with mice [8], rats [9], rabbits [10], and wildlife, such as antelope and giraffe [11].…”

Biological Functions of Prokaryotic Amyloids in Interspecies Interactions: Facts and Assumptions

“…Thus, the crucial role of amyloids of biofilms in adhesion is apparently widespread across various prokaryotes, thus allowing us to suppose that there are numerous still unknown biofilm-associated amyloids underlying the pathogenesis and development of infectious diseases. Considering that the number of only human pathogenic bacteria species is about 1500 [ 136 ] and 65% of them form biofilms in disease-associated processes [ 55 ], the real number of such prokaryotic amyloids involved in pathogenesis in humans and animals could exceed hundreds and even thousands. The interactions between bacteria in microbial communities represent another type of interspecies interactions where the bacterial biofilm amyloids are involved by providing the cell adhesion to heterogeneous exopolysaccharides and where the number of yet unidentified prokaryotic amyloids could be remarkably high.…”

Expanding host specificity and pathogen sharing beyond viruses

“…To undertake such a comparison, Shaw et al. (2020) combined an exhaustive literature search, with cross‐validation from other large‐scale data sets, to compile 12,212 interactions between 2,656 vertebrate hosts and 2,595 viral and bacterial pathogens. Although multi‐host pathogens have generally been considered common and widespread (Cleaveland, Laurenson, & Taylor, 2001), this new analysis instead demonstrates that half of all viruses and bacteria are specialized on their hosts (Figure 1).…”

“…From the host perspective, Shaw et al. (2020) show that viral and bacterial pathogen richness were positively correlated, suggesting animals that harbour more zoonotic viruses are also more likely to harbour more zoonotic bacteria. As with the pathogen trait analyses, study effort was also a consistent predictor of zoonotic richness for both viruses and bacteria.…”

“…Here, Shaw et al. (2020) illuminate key similarities in the host range and zoonotic potential of these two pathogens, with particular attention to the importance of robustly characterizing phylogenetic host breadth and how host phylogenetic distance is a key determinant of cross‐species transmission across pathogens. More broadly, the authors provide a valuable resource for future comparative research, which will be critical to understand the differences between viral and bacterial zoonoses and their disease risk.…”