# A Systematic Review of the Relationship Between Host Personality Traits and Parasitic Infection

## TL;DR

This review explores how host personality traits relate to parasitic infections, finding complex and context-dependent patterns with no universal rules.

## Contribution

The paper provides a systematic synthesis of 54 studies, highlighting the dynamic and multi-feedback nature of host personality and parasitic infection.

## Key findings

- The relationship between host personality and parasitic infection is complex and varies by context.
- Biological factors like host sex and parasite type significantly influence the personality–infection relationship.
- Different personality traits may show different associations with parasitic infection.

## Abstract

Parasitism is a fundamental type of interspecific interaction, and exploring the mechanisms behind parasitic infection is vital for understanding the role of parasitism in shaping host population dynamics, host–parasite co-evolution, and ecosystem functioning. Previous studies suggested that parasitism is closely related to many traits of both hosts and parasites, and the relationship between host personality traits and parasitic infection has been widely explored in recent decades. This review summarizes main findings of the relevant empirical works. The results of previous studies are complex and context-dependent, with positive, negative, and neutral associations being repeatedly reported. We then analyzed the potential mechanisms behind these patterns, research methods and the limitations of the previous studies, and new directions in future studies were also discussed.

Parasitism plays an important role in many fundamental ecological processes and is widespread both geographically and taxonomically. Interactions between parasites and hosts are often complex, and much attention has been paid to the relationship between host traits and parasitism. However, a comprehensive review of the association between host personality and parasitic infection is lacking. In this review, we systematically synthesized 54 studies published over the past few decades. Generally, the relationship between animal personality traits and parasitic infection is complex, and no generic pattern exists. Many biological processes may be involved, and biological factors (such as host sex and parasite type) may significantly shape the personality–infection relationship. Different personality traits may also indicate different relationships with parasitic infection. We confirmed that host personality and parasitic infection exhibit a mutually influential, multi-feedback dynamic. Finally, several research gaps were described, and we emphasized the importance of incorporating the BACI design in experiments.