Borrelia burgdorferi and Anaplasma phagocytophilum coinfect and are transmitted by Ixodes species ticks. Clinical indicators suggest that A. phagocytophilum coinfection contributes to the severity, dissemination, and, possibly, sequelae of Lyme disease. Previous in vitro studies showed that spirochete penetration through human brain microvascular endothelial cells of the blood-brain barrier is ...

Polymerase chain reaction integrated with sequence analysis was carried out to investigate the natural Anaplasma phagocytophilum infection in ticks and rodents from a forest area of Jilin Province, China. Four (4.0%) of 100 Ixodes persulcatus and 2 (0.7%) of 286 Dermacentor silvarum ticks collected by flagging vegetation were positive. Nine (8.8%) of 102 rodents were infected, as well as 2 (2.8...

Polymorphonuclear leukocytes (PMNs or neutrophils) are essential to human innate host defense. However, some bacterial pathogens circumvent destruction by PMNs and thereby cause disease. Anaplasma phagocytophilum, the agent of human granulocytic anaplasmosis, survives within PMNs in part by altering normal host cell processes, such as production of reactive oxygen species (ROS) and apoptosis. T...

Anaplasma phagocytophilum is the causative agent of human granulocytic anaplasmosis (HGA), an emerging tick-borne zoonosis. The pathogen utilizes cattle, sheep, goats, and wide variety of animal species as reservoirs and members of genus Ixodes tick as vectors. Although conditions for transmission of the agent in Kingdom of Saudi Arabia do exist, there is no work of any kind was done to address...

Mast cells are sentinels for infection. Upon exposure to pathogens, they release their stores of proinflammatory cytokines, chemokines, and histamine. Mast cells are also important for the control of certain tick-borne infections. Anaplasma phagocytophilum is an obligate intracellular tick-transmitted bacterium that infects neutrophils to cause the emerging disease granulocytic anaplasmosis. A....

Human granulocytic anaplasmosis is currently not nationally notifiable in Canada. This for the most part accounts for gross under-estimation of true incidence and prevalence of HGA and would potentially culminate in clinical missed opportunities. To the best of our knowledge, this is the first report on the seroprevalence of Anaplasma phagocytophilum in a Canadian jurisdiction with known establ...