BACKGROUND

Echinococcosis remains highly endemic in some nomadic communities on the Qinghai-Tibet Plateau, China, where alveolar echinococcosis (AE) and cystic echinococcosis (CE) exhibit notably high prevalence rates of 3.64% and 2.37%, respectively. Recent settlement expansion in the region has raised concerns, as smaller, remote settlements often lacked waste disposal and sewage systems, potentially facilitating echinococcosis transmission. The aim of this study is to investigate how settlement characteristics influence echinococcosis transmission.

FINDINGS

The study was conducted from 2022-2024 in nomadic communities of Shiqu County in China. The overall prevalence rate of echinococcosis in 51 settlements was found to be 2.34% (321/13,701; 95% CI: 2.10-2.61), which included a prevalence rate of 1.62% (222/13,701; 95% CI: 1.42-1.85) for AE and a prevalence rate of 0.72% (99/13,701; 95% CI: 0.59-0.88) for CE. The prevalence rate of AE was significantly (χ = 49.57, P < 0.01) higher than that of CE. Settlements with a smaller population size (Z = -4.27, P < 0.01), a greater distance to the township center (Z = 2.66, P < 0.01) and a higher density of owned dogs (Z = 5.90, P < 0.01) were associated with higher prevalence rates of CE. These associations were also observed for AE prevalence, except for the density of owned dogs.

CONCLUSIONS

This study indicates that the transmission of AE was more active than that of CE in the nomadic communities. Smaller, remote settlements had higher prevalence rates for both CE and AE. The density of owned dogs was a significant risk factor for CE prevalence but not for AE prevalence. Targeted interventions are needed in these high-risk settlements. Future research should investigate how settlement characteristics interact with hygiene practices, the infection status of intermediate and definitive hosts, and their population dynamics to better understand combined effects on echinococcosis prevalence.