Interspecies Differences And Influencing Factors Of Host Pathogen Transmission Ability

Multi-host pathogens can infect multiple host species and circulate within these hosts.It has been shown that host status,for a specific pathogen,might be determined by various factors,including host phylogeny,diet,habitat and distribution range.In addition,studies have shown that host competence can also vary considerably between different species.The inter-specific variation in host status and host competence might result from the complex effects on host-pathogen interaction by habitat,geographic distribution,climate,diet.However,only a few studies tried to explore the inter-specific variation in host status/host competence and driving factors.These studies indicated that species' immune defense,which determines host status and host competence,might be correlated with their life-history traits.In addition,due to the co-evolution of host and pathogen,the relatedness of hosts can partly explain the inter-specific variation of pathogens' host ranges and host competence.Understanding host status and host competence is of importance in the control and prevention of infectious diseases.Therefore,more studies are needed to disclose the factors driving the inter-specific variation in host status and host competence.In this study,we explored the relationship between birds' life-history traits and their competence for West Nile virus which usually transmitted through mosquitoes.Our results suggested that neither of three life-history traits(i.e.body mass,clutch size and incubation time)showed any significant relationship with host competence.We consider this result might be caused by the complex of the measures of host competence,or the multiple sources for our analyzed dataset.In addition,host competence showed strong phylogenetic signal,suggesting that host phylogeny and host relatedness may partly explain the inter-specific variation in host competence.We also explored the relationships between waterfowl species' host status for avian influenza(AIV)and life-history traits.Our results suggested that,body mass is the most important factor in determining host status.The probability of being host was positively correlated with body mass and clutch size,while negatively associated with incubation time.Our model has a relative good predictive accuracy,suggesting that waterfowl life-history traits can,to some extent,explain the interspecific variation of host status for AIV.However,our model has a relative low specificity,which means a relative lower predictive power of our model in predicting non-host species.We suggest future studies take into account more ecological attributes(such as diet,foraging substrate)to increase the predictive accuracy of the model.In summary,this study,taking two typical infectious diseases with different transmission types as examples,explored the effects of species' life-history traits on host status and host competence.Our results might not only contribute to a better understanding of the interspecific variation in host-pathogen interactions,but also be beneficial to disease prediction,control and prevention.