Koch thus established Koch’s postulates, a sequence of experimental steps for directly relating a specific microbe to a specific disease
The protection from disease provided by vaccination (or by recovery from the disease itself) is called immunity.
Treatment of disease by using chemical substances is called chemotherapy.
Chemicals produced natu- rally by bacteria and fungi to act against other microorganisms are called antibiotics.
Chemotherapeutic agents prepared from chemicals in the laboratory are called synthetic drugs
he found a chemotherapeutic agent called salvarsan, an arsenic derivative effective against syph- ilis. The agent was named salvarsan because it was considered to offer salvation from syphilis and it contained arsenic.
Mycology, the study of fungi, includes medical, agricultural, and ecological branches
Parasitology is the study of protozoa and parasitic worms. Because many parasitic worms are large enough to be seen with the unaided eye,