USAID:10.1128/CVI.00385-07
USAID:10.1128/IAI.68.4.2215-2223.2000
USAID:10.1128/IAI.70.3.1417-1421.2002
USAID:10.1128/IAI.73.1.287-297.2004
USAID:10.1128/IAI.01420-07