Neonatal Anaplasma platys infection in puppies: Further evidence for possible vertical transmission.

Anaplasma platys, the aetiological agent of infectious canine cyclic thrombocytopaenia, infects platelets of dogs, usually causing mild or asymptomatic disease. Although A. platys is transmitted by ticks, as for other Anaplasma species, alternative modes of transmission may be involved. The aim of the present study was to evaluate the occurrence of A. platys infection in litters of puppies, which could suggest possible vertical transmission. Twelve litters, together with the respective bitches, were included in the study for the detection of A. platys DNA by PCR, followed by sequencing. Five puppies, from 2/4 litters <28 days of age, tested positive for A. platys DNA. No puppies from eight litters 1-3 months of age tested positive for A. platys DNA. The identical sequences (16S rRNA and gltA partial gene), the absence of ticks on puppies at the time of collection and the young age of the five infected puppies suggest vertical transmission of A. platys. This mode of transmission might contribute to the maintenance and spread of the pathogen in canine populations.