Molecular Detection of Anaplasma spp. in Horses From Golestan Province, Northern Iran

Anaplasmosis is a bacterial zoonotic disease that affects both humans and many animals. In horses, anaplasmosis manifests as a seasonal, infectious, and febrile disease caused by bacteria of the genus Anaplasma. Since the transmission of this disease is primarily mediated by arthropods such as ticks, it holds significant public health importance.

The present study aims to investigate the prevalence of anaplasmosis in horses in northern Iran (Golestan Province).

A total of 350 blood samples were randomly collected from asymptomatic horses between December 2023 and April 2024. Genomic DNA was extracted from whole blood, and conventional PCR targeting a partial fragment of the 16S rRNA gene was performed for the detection of Anaplasma spp.

The prevalence of infection was 15.7% (95% CI: 12.2%-19.8%). Significant variation was observed between geographic regions, with the highest prevalence in Aq Qala (24.3%) and the lowest in Gorgan (7.9%). Age and sex showed no significant effect on infection rates.

Due to the loss and degradation of DNA samples, sequencing of PCR-positive samples was not performed, and identification was carried out at the genus level.

These findings demonstrate the detection of Anaplasma spp. DNA in horse blood samples from Golestan Province, northern Iran, and highlight the need for further studies on vector identification, species-level characterization, and the clinical significance of these molecular findings. This study provides baseline molecular epidemiological data on Anaplasma spp. in horses in Iran, contributing to future surveillance and control programs.