carrier strain

car·ri·er strain

a bacterial strain that is contaminated with a bacteriophage of low infectivity.
References in periodicals archive ?
Distribution of serogroups and sequence types in disease-associated and carrier strains of Neisseria meningitidis isolated in China between 2003 and 2008.
In-vitro bacteriocin-mediated antagonism by oral streptococci against human carrier strains of staphylococci.
Of 80 healthy persons in the patients' villages, 28 (35%) carried meningococci; 20 of 21 W135 carrier strains were ST-2881.
Although most European and American isolates were highly diverse, one clonal grouping was identified in sporadic disease and carrier strains isolated over the last 2 decades in the United Kingdom, the Netherlands, Germany, and the United States.