Se. Farhat et al., Efficacy of a swab transport system in maintaining viability of Neisseria gonorrhoeae and Streptococcus pneumoniae, J CLIN MICR, 39(8), 2001, pp. 2958-2960
The efficacy of swab transport systems in maintaining viability of Neisseri
a gonorrhoeae and Streptococcus pneumoniae is crucial both for establishing
definitive diagnosis and for monitoring emerging resistance. We tested the
efficacy of a newly modified Amies charcoal swab transport system, the Sta
rSwab SP131X (Starplex Scientific, Inc., Etobicoke, Ontario, Canada), by us
ing a combined total of 31 clinical and American Type Culture Collection st
ock reference strains of N. gonorrhoeae and S. pneumoniae in 46 suspensions
of concentrations ranging from 10(5) to 10(8) CFU/ml. Triplicate swabs per
strain held at room temperature for 0, 24, and 48 h were plated without pr
ior vortexing, and their growths were graded. All 31 strains were viable at
0 and 24 h. Gonococcal viability at 48 h varied considerably, even among s
trains with comparable inoculum sizes, suggesting that viability might be s
train dependent and confirming the different structural and growth profiles
of gonococcal strains. S. pneumoniae strains showed consistent viability,
with all strains recovered at all holding periods. This study demonstrates
that the StarSwab SP131X is capable of maintaining the viability of N. gono
rrhoeae and S. pneumoniae for at least 24 and 48 h, respectively, and reinf
orces the need for adequate sampling and for timely processing of specimens
to maintain optimum performance.