Wild Boars as Hosts of Human-Pathogenic Anaplasma phagocytophilum Variants

liams for their clarifi cation on state and national regulations aimed at reducing the risks of salmonellosis and their advice on conducting this survey. We also thank members and staff of the National Association of State Public Health Veterinarians and the National Resource Center for Health and Safety in Child Care and Early Education for their assistance. a population-based, case-control study.nas and Salmonella Marina infection in children: a refl ection of the increasing incidence of reptile-associated sal-monellosis in the United States. 6. Centers for Disease Control and Prevention. Multistate outbreak of human Salmonella Typhimurium infections associated with aquatic frogs—United States, Wild Boars as Hosts of Human-Pathogenic Anaplasma phagocytophilum Variants To the Editor: Michalik et al. (1) reported a 12% prevalence of Ana-plasma phagocytophilum, the caus-ative agent of human granulocytic anaplasmosis and tick-borne fever of ruminants, in wild boars in Poland. A. phagocytophilum has been reported with low prevalence among wild boar in the Czech Republic, Slovenia (2), and Japan (3). In Spain and Missis-sippi, United States, A. phagocyto-philum in wild boars or feral pigs, respectively , has not been reported (4,5). Furthermore, in Slovenia and Poland, the A. phagocytophilum gene sequences found in samples from wild boars were identical to those found in samples from humans and the tick vector Ixodes ricinus (1). These results suggested , as pointed out by Michalik et al. (1), that wild boar might play a role in the epizootiology of A. phagocyto-philum by serving as a natural reservoir host, at least in some regions. To test this hypothesis, we conducted transcriptomics studies to characterize host response to A. phagocy-tophilum infection in naturally and experimentally infected boars (6,7). The results suggested that boars are susceptible to A. phagocytophilum, but are able to control infection, mainly through activation of innate immune responses and cytoskeleton rearrangement to promote phagocy-tosis and autophagy. Control of A. phagocytophilum infection in boars might result in infection levels below PCR detection or infection clearance, contributing to the low percentage of infection prevalence detected for this species in most regions. The low detection levels suggest that boars have a low or no impact as a reservoir host for A. phagocytophilum. Even if boars remain persistently infected with A. phagocytophilum at low levels by downregulating some adap-tive immune genes and delaying the apoptotic death of neutrophils through activation of the Jak-STAT pathway, among other mechanisms (6), their role as a source of infection for …