Researchers from the Enteric, Zoonotic and Vector-borne Diseases, Communicable Diseases, Emergency Preparedness and Response, Public Health Ontario, Toronto, Ontario, Canada, in a study published in PLoS One last week looked at the clinical manifestations of reported Lyme disease cases in Ontario, Canada: 2005-2014.

Erythema migrans/James Gathany

Here are some of the findings:

During the study period, 1,230 cases due to Borrelia burgdoferi were reported in Ontario with annual incidence rates ranging from 0.32 (2006) to 2.16 (2013) cases per 100,000 population.

Seventy percent of cases had erythema migrans (EM) and the proportion of cases with EM increased over time. Other clinical manifestations included flu-like (75%), arthritic (42%), neurologic (41%) and cardiac (6%) symptoms.

Early localized disease (n = 415) manifested with EM (87%) and flu-like (57%) symptoms; early disseminated disease (n = 216) manifested with neurologic (94%), cardiac (10%) and EM (63%) symptoms; and late disseminated disease (n = 475) manifested with EM (62%), neurologic (55%), cardiac (9%), and arthritic symptoms (i.e., arthralgia (93%) and arthritis (7%)). Early localized and early disseminated cases (88% each) occurred primarily from May through September, compared to late disseminated cases (81%).

Read more at Clinical manifestations of reported Lyme disease cases in Ontario, Canada: 2005–2014