Staphylococcus aureus colonization of healthy military service members in the United States and Afghanistan.
BACKGROUND
Staphylococcus aureus [methicillin-resistant and methicillin-susceptible (MRSA/MSSA)] is a leading cause of infections in military personnel, but there are limited data regarding baseline colonization of individuals while deployed. We conducted a pilot study to screen non-deployed and deployed healthy military service members for MRSA/MSSA colonization at various anatomic sites and assessed isolates for molecular differences.


METHODS
Colonization point-prevalence of 101 military personnel in the US and 100 in Afghanistan was determined by swabbing 7 anatomic sites. US-based individuals had received no antibiotics within 30 days, and Afghanistan-deployed personnel were taking doxycycline for malaria prophylaxis. Isolates underwent identification and testing for antimicrobial resistance, virulence factors, and pulsed-field type (PFT).


RESULTS
4 individuals in the US (4 isolates- 3 oropharynx, 1 perirectal) and 4 in Afghanistan (6 isolates- 2 oropharynx, 2 nare, 1 hand, 1 foot) were colonized with MRSA. Among US-based personnel, 3 had USA300 (1 PVL+) and 1 USA700. Among Afghanistan-based personnel, 1 had USA300 (PVL+), 1 USA800 and 2 USA1000. MSSA was present in 40 (71 isolates-25 oropharynx, 15 nare) of the US-based and 32 (65 isolates- 16 oropharynx, 24 nare) of the Afghanistan-based individuals. 56 (79%) US and 41(63%) Afghanistan-based individuals had MSSA isolates recovered from extra-nare sites. The most common MSSA PFTs were USA200 (9 isolates) in the US and USA800 (7 isolates) in Afghanistan. MRSA/MSSA isolates were susceptible to doxycycline in all but 3 personnel (1 US, 2 Afghanistan; all were MSSA isolates that carried tetM).


CONCLUSIONS
MRSA and MSSA colonization of military personnel was not associated with deployment status or doxycycline exposure. Higher S. aureus oropharynx colonization rates were observed and may warrant changes in decolonization practices.
Brooke Army Medical Center/San Antonio Military Medical Center, Fort Sam Houston, Fort Sam Houston, TX 78234, USA.
Todd J
TJ
Vento
Tatjana P
TP
Calvano
David W
DW
Cole
Katrin
K
Mende
Elizabeth A
EA
Rini
Charla C
CC
Tully
Michael L
ML
Landrum
Wendy
W
Zera
Charles H
CH
Guymon
Xin
X
Yu
Miriam L
ML
Beckius
Kristelle A
KA
Cheatle
Clinton K
CK
Murray
D000328:Adult; D000346:Afghanistan; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D008297:Male; D008889:Military Personnel; D013211:Staphylococcus aureus / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification*; D014481:United States; D037521:Virulence Factors / Q000378:metabolism
D037521:Virulence Factors