# Detection and characterization of Candidatus mycoplasma haemolamae haplotype in South American camelids farmed in Italy

## TL;DR

This study found a high prevalence of a blood-borne bacterium in farmed South American camelids in Italy and identified two genetic variants of the pathogen.

## Contribution

The study characterizes two CMhl haplotypes and identifies risk factors for infection in SAC farmed in Italy.

## Key findings

- CMhl was detected in 42.7% of SAC blood samples in Italy.
- Two CMhl haplotypes were identified, with haplotype #1 being most common.
- Warmer seasons and larger herd sizes were significantly associated with higher CMhl positivity.

## Abstract

‘Candidatus Mycoplasma haemolamae’ (CMhl) is a hemotropic bacterium infecting South American Camelids (SAC), whose epidemiology and clinical significance are still not fully elucidated. This study investigated CMhl by qPCR in blood samples of alpacas (Vicugna pacos) and llamas (Lama glama) in Italy in 2021–2024, characterizing CMhl haplotypes based on partial 16 S rRNA sequences and defining haematological findings in a subset of CMhl-infected animals. Statistical analysis was performed to detect potential risk factors associated with CMhl positivity. Out of 206 animals (200 alpacas and 6 llamas), CMhl was detected by qPCR in 88 (42.7%) animals. CMhl haplotype #1 and #2 were detected in 42.2% and 0.5% of the animals, respectively. Binary logistic regression analysis showed that higher CMhl positivity was significantly associated with larger herd size (P = 0.011), Northern Italy area of origin (P = 0.031) and warmer seasons (P = 0.003). The detection of two CMhl haplotypes confirms the high diffusion of CMhl in SAC farmed in Italy. Results confirm that CMhl usually causes subclinical infections, suggesting that antimicrobial treatment is likely not necessary based on qPCR positivity alone. Results focusing on the association of CMhl positivity with warm temperatures and large herd size suggest the need of further studies on the genetic features, epidemiology and immune response in CMhl-positive SAC from Italy, with emphasis on understanding potential vector transmission.

The online version contains supplementary material available at 10.1007/s11259-025-11033-y.