Listeriosis in South American camelids – A review

The main aim of the present study was to review the general aspects of Listeria and the clinical manifestation of the disease listeriosis in humans and domestic ruminants, with emphasis on clinical signs in South American camelids. Camelids are susceptible to infection by Listeria; however, it appears that the prevalence of listeriosis in camelids is low, given that few cases have been reported. The species Listeria monocytogenes is associated with all reported cases. To our knowledge, there are no reported cases of listeriosis in vicunas (Vicugna vicugna) and guanacos (Lama guanicoe).

The clinical manifestations of listeriosis in llamas and alpacas are similar to in domestic ruminants and humans, namely meningoencephalitis, encephalitis, septicaemia, abortion, otitis media/interna and polyarthritis. Listerial mastitis and gastroenteritis has not yet been described in camelids. Despite reported cases, there is no specific mention of listeriosis associated with shedding of bacteria in faeces or milk. The occurrence of listeriosis in camelids needs to be confirmed and clinical signs defined.