diseases carried from person to person through other hosts such as animals or insects are known as
Zoonosis Zoonoses are infectious diseases of animals (usually vertebrates) that can naturally be transmitted to humans.[1][2]
Lyme disease Lyme disease is the most common disease spread by ticks in the Northern Hemisphere.[13] It is estimated to affect 300,000 people a year in the United States and 65,000 people a year in Europe.[2][4] Infections are most common in the spring and early summer.[2] Lyme disease was diagnosed as a separate condition for the first time in 1975 in Old Lyme, Connecticut.[14] It was originally mistaken for juvenile rheumatoid arthritis.[14] The bacterium involved was first described in 1981 by Willy Burgdorfer.[15] Chronic symptoms are well described and are known as post-treatment Lyme disease syndrome, often called chronic Lyme disease.[12] Some healthcare providers claim that it is due to ongoing infection; however, this is not believed to be true, due to the inability to detect infectious organisms after standard treatment.[16] A Lyme vaccine was marketed in the US between 1998 and 2002; it was withdrawn from the market due to poor sales, originally due to lack of reimbursement by insurance companies and then due to rumors about adverse effects.[2][17] Research is ongoing to develop new vaccines.[2]