Abstract
New typhoid vaccines have been sought to replace the reactogenic parenteral whole cell vaccines. Both Ty21a, a live oral attenuated Vi-negative Salmonella typhi vaccine strain, and parenteral Vi polysaccharide vaccine are safe and efficacious in field trials. To achieve potentially greater protective efficacy, a derivative of Ty21a that expresses Vi polysaccharide was prepared and its safety and immunogenicity assessed in 27 adult volunteers. The volunteers received either one dose of 5 x 105, 5 x 107, or 5 x 109 cfu or three doses of 5 x 109 cfu of lyophilized vaccine and were observed for adverse effects on a research isolation ward. The vaccine was well tolerated; however, at the highest dose, 13% of volunteers had mild diarrhea. Serial blood cultures were negative for the vaccine strain. Vaccine was shed in the stool of most volunteers at the higher doses for 1-4 days. No serum antibodies to Vi, circulating cells secreting antibody to Vi, or jejunal fluid antibodies to Vi were detected in any volunteer.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 901-904 |
| Number of pages | 4 |
| Journal | Journal of Infectious Diseases |
| Volume | 163 |
| Issue number | 4 |
| State | Published - Apr 1991 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Public Health, Environmental and Occupational Health
- Immunology
Cite this
Lack of immune response to the Vi component of a Vi-positive variant of the Salmonella typhi live oral vaccine strain Ty21a in human studies. / Tacket, Carol O.; Losonsky, Genevieve; Taylor, David N.; Baron, Louis S.; Kopecko, Dennis; Cryz, Stanley; Levine, Myron M.
In: Journal of Infectious Diseases, Vol. 163, No. 4, 04.1991, p. 901-904.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Lack of immune response to the Vi component of a Vi-positive variant of the Salmonella typhi live oral vaccine strain Ty21a in human studies
AU - Tacket, Carol O.
AU - Losonsky, Genevieve
AU - Taylor, David N.
AU - Baron, Louis S.
AU - Kopecko, Dennis
AU - Cryz, Stanley
AU - Levine, Myron M.
PY - 1991/4
Y1 - 1991/4
N2 - New typhoid vaccines have been sought to replace the reactogenic parenteral whole cell vaccines. Both Ty21a, a live oral attenuated Vi-negative Salmonella typhi vaccine strain, and parenteral Vi polysaccharide vaccine are safe and efficacious in field trials. To achieve potentially greater protective efficacy, a derivative of Ty21a that expresses Vi polysaccharide was prepared and its safety and immunogenicity assessed in 27 adult volunteers. The volunteers received either one dose of 5 x 105, 5 x 107, or 5 x 109 cfu or three doses of 5 x 109 cfu of lyophilized vaccine and were observed for adverse effects on a research isolation ward. The vaccine was well tolerated; however, at the highest dose, 13% of volunteers had mild diarrhea. Serial blood cultures were negative for the vaccine strain. Vaccine was shed in the stool of most volunteers at the higher doses for 1-4 days. No serum antibodies to Vi, circulating cells secreting antibody to Vi, or jejunal fluid antibodies to Vi were detected in any volunteer.
AB - New typhoid vaccines have been sought to replace the reactogenic parenteral whole cell vaccines. Both Ty21a, a live oral attenuated Vi-negative Salmonella typhi vaccine strain, and parenteral Vi polysaccharide vaccine are safe and efficacious in field trials. To achieve potentially greater protective efficacy, a derivative of Ty21a that expresses Vi polysaccharide was prepared and its safety and immunogenicity assessed in 27 adult volunteers. The volunteers received either one dose of 5 x 105, 5 x 107, or 5 x 109 cfu or three doses of 5 x 109 cfu of lyophilized vaccine and were observed for adverse effects on a research isolation ward. The vaccine was well tolerated; however, at the highest dose, 13% of volunteers had mild diarrhea. Serial blood cultures were negative for the vaccine strain. Vaccine was shed in the stool of most volunteers at the higher doses for 1-4 days. No serum antibodies to Vi, circulating cells secreting antibody to Vi, or jejunal fluid antibodies to Vi were detected in any volunteer.
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UR - http://www.scopus.com/inward/citedby.url?scp=0025908003&partnerID=8YFLogxK
M3 - Article
C2 - 2010645
AN - SCOPUS:0025908003
VL - 163
SP - 901
EP - 904
JO - Journal of Infectious Diseases
JF - Journal of Infectious Diseases
SN - 0022-1899
IS - 4
ER -