Abstract
Background:
Newcastle disease is an extremely contagious and economically damaging poultry disease caused by Avian orthoavulavirus 1 (NDV), a member of Paramyxoviridae.

Aim:
This study was conducted as a systematic review and meta-analysis aimed at assessing NDV prevalence among poultry populations in mainland China.

Methods:
A total of 25 relevant epidemiological studies published between 1979 and 2023 were analyzed following the MOOSE guidelines.

Results:
Our meta-analysis revealed an overall NDV prevalence of 2.17% (95% CI:1.95–2.42%) with significant heterogeneity (I² = 97.1%, p < 0.001). Southern China exhibited the highest individual study prevalence, while southwestern regions reported the lowest (0.32%). No aggregated regional prevalence exceeded 10%, suggesting localized outbreaks. Prevalence decreased from 3.19% (prior to 2013) to 1.03% (post-2013 era), reflecting improved biosecurity and vaccination. RT-PCR-based studies showed lower heterogeneity (I² = 89.5%) compared to serological assays (I² = 97.1%), highlighting the challenges in comparing prevalence estimates across different diagnostic methods and underscoring the need for standardized diagnostics emphasizing the need for standardized diagnostics. Publication Bias: Funnel plot asymmetry indicated underrepresentation of small-scale studies (p = 0.003).

Conclusion:
These results highlight persistent NDV challenges in high-density poultry areas (e.g., southern China) and underscore the importance of molecular diagnostics (RT-PCR) for accurate surveillance. Given persistent hotspots in high-density poultry areas (e.g., Guangdong), targeted vaccination and region-specific biosecurity measures are critical to mitigating NDV transmission.

Key words: Systematic review; Newcastle Disease Virus; China; Epidemiology; Poultry.