# A Systematic Review and Meta-Analysis on the Global Seroprevalence of Porcine Reproductive and Respiratory Virus (PRRSV) in Pigs and Wild Boars: A Widespread and Impactful Swine Virus

## TL;DR

This study reviews global data to show that PRRSV is widespread in pigs, especially in Asia, and highlights factors like animal density that contribute to its spread.

## Contribution

The study provides the first comprehensive meta-analysis of PRRSV seroprevalence across pigs and wild boars globally.

## Key findings

- The global pooled seroprevalence of PRRSV is 14% with high variability between regions.
- Asia has the highest PRRSV prevalence at 29%, and domestic pigs are more affected than wild boars.
- Animal density is a key factor associated with increased PRRSV prevalence.

## Abstract

Porcine reproductive and respiratory virus (PRRSV) is a widespread and impactful virus of swine. By conducting a systematic review and meta-analysis, this study summarizes global serological data on PRRSV in pigs and wild boars. The results obtained underscore a high disease burden in domestic pigs, especially in some regions of the world, and identify key factors associated with increased prevalence.

Porcine reproductive and respiratory virus (PRRSV) has a significant clinical and economic impact on pig farming. The purpose of this study was to assess the global seroprevalence of PRRSV in pigs and wild boars using a systematic review and meta-analysis approach. Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, a systematic review and meta-analysis on global serological data of PRRSV in pigs and wild boars was conducted. Studies published between 1993 and 2025 were searched in three electronic databases, including PubMed, Web of Science, and Scopus. A total of 86 publications, belonging to 41 countries and including 690,771 animals, were deemed eligible. Following the identification and removal of outlier studies, the pooled serological prevalence was 14% (95% CI: 9–19%), and a high between-study heterogeneity was detected (I2 = 99.9%, p < 0.000001). Subgroup analyses showed statistically significant differences according to continents, with the highest prevalence found in Asia (P: 29%, 95% CI: 16–43%), and species, with a higher prevalence in domestic pigs (P: 26%, 95% CI: 18–35%) than in wild boars (P: 2%, 95% CI: 1–3%). Overall, the information hereby presented provides an overview of the global PRRSV situation and identifies key factors associated with increased prevalence, primarily related to animal density. These insights could inform future surveillance strategies and help target interventions to mitigate the disease burden and safeguard swine health.