pathogen

As a noun pathogen

is (pathology|immunology) any organism or substance, especially a microorganism, capable of causing disease, such as bacteria, viruses, protozoa or fungi microorganisms are not considered to be pathogenic until they have reached a population size that is large enough to cause disease.

As an adjective seronegative is

.

As nouns the difference between pathogen and coreceptor

is that pathogen is any organism or substance, especially a microorganism, capable of causing disease, such as bacteria, viruses, protozoa or fungi. Microorganisms are not considered to be pathogenic until they have reached a population size that is large enough to cause disease while coreceptor is a cell surface receptor that binds a signaling molecule in addition to a primary receptor in order to facilitate ligand recognition and initiate a biological process, such as entry of a pathogen into a host cell.

As a noun pathogen

is (pathology|immunology) any organism or substance, especially a microorganism, capable of causing disease, such as bacteria, viruses, protozoa or fungi microorganisms are not considered to be pathogenic until they have reached a population size that is large enough to cause disease.

As an adjective seropositive is

.

As nouns the difference between pathogen and seropositivity

is that pathogen is (pathology|immunology) any organism or substance, especially a microorganism, capable of causing disease, such as bacteria, viruses, protozoa or fungi microorganisms are not considered to be pathogenic until they have reached a population size that is large enough to cause disease while seropositivity is the quality or state of being seropositive, of having blood serum that tests positive for a given pathogen, especially hiv.