Safety and immunogenicity of an oral, killed enterotoxigenic Escherichia coli-cholera toxin B subunit vaccine in Egyptian adults.
Enterotoxigenic Escherichia coli (ETEC) is the leading cause of bacterial diarrhea in young children in developing countries. The safety and immunogenicity of a killed, oral ETEC vaccine consisting of whole cells plus recombinantly produced cholera toxin B subunit (rCTB) was evaluated in Egypt, which is endemic for ETEC diarrhea. Seventy-four healthy Egyptian adults (21-45 years old) were randomized and received two doses of the ETEC/rCTB vaccine (E003) or placebo 2 weeks apart. The frequency of adverse events after either dose did not differ by treatment group, and no severe adverse events were reported. After vaccination, peripheral blood IgA B cell responses to CTB (100%) and to vaccine colonization factor antigens CFA/I (94%), CS4 (100%), CS2 (81%), and CS1 (69%) were significantly higher than response rates for the placebo group. These favorable results in Egyptian adults indicate that the ETEC/rCTB vaccine is a promising candidate for evaluation in younger age groups in this setting.
Savarino
S J
SJ
US Naval Medical Research Unit No. 3, Cairo, Egypt. savarino@namru3.navy.mil
Brown
F M
FM
Hall
E
E
Bassily
S
S
Youssef
F
F
Wierzba
T
T
Peruski
L
L
El-Masry
N A
NA
Safwat
M
M
Rao
M
M
Jertborn
M
M
Svennerholm
A M
AM
Lee
Y J
YJ
Clemens
J D
JD
D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D001428:Bacterial Vaccines / Q000276:immunology*; D004534:Egypt; D004926:Escherichia coli / Q000276:immunology*; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D008297:Male; D008875:Middle Aged; D014614:Vaccines, Synthetic / Q000276:immunology*
D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D007070:Immunoglobulin A; D014614:Vaccines, Synthetic