Final answer:
A zoonosis is any disease that is transmissible from animals to humans, encompassing diseases from vertebrate and sometimes invertebrate animals. Examples include rabies, HIV, influenza, and emerging diseases like COVID-19 and SARS, which can result from increased human interaction with wildlife. Epidemiologists investigate and help prevent such diseases.
Step-by-step explanation:
A zoonosis is any disease transmissible from animals to humans. This term is used broadly and refers to diseases which are transferred from a vertebrate animal to a human and in some cases, from all animals including invertebrates. For example, rabies is a classic zoonotic disease spread from animals to humans through bites and contact with infected saliva.
More severe examples of zoonotic diseases include diseases such as HIV, influenza, and even the recent COVID-19, which are thought to have originated in animals and then mutated to become more virulent in human hosts. Other instances of zoonotic diseases can emerge when humans increase their interactions with wildlife, such as the consumption of wild animals leading to outbreaks like SARS and potentially new types of coronavirus.
Epidemiologists, who can be thought of as disease detectives, conduct investigations to determine the pathogen's origin and work on preventing future outbreaks. This research, often conducted by veterinarians and scientists, is crucial in understanding the transmission of these diseases and preventing a widespread health crisis.