Not exactly what you are looking for but similar flavor. The most obvious option to me is liar. claim, verb. state or assert that something is the case, typically without providing evidence or proof. purport, verb. to claim to be or do a particular thing when this claim may not be true.
Background. Leptospirosis is an infectious disease of humans and animals that is caused by pathogenic spirochetes of the genus Leptospira. It is considered the most common zoonosis in the world.Leptospirosis is distributed worldwide (sparing the polar regions) but is most common in the tropics.Leptospirosis has been recognized as a re-emerging infectious disease among animals and humans and has the potential to become even more prevalent with advancing climate change and related trends.eptospirosis is distributed worldwide (sparing the polar regions) but is most common in the tropics. Leptospirosis has been recognized as a re-emerging infectious disease among animals and humans and has the potential to become even more prevalent with advancing climate change and related trends.
Leptospirosis is a potentially serious disease caused by the bacterium Leptospira interrogans. It affects dogs but can also infect a wide variety of domestic and wild animals as well as humans.