Prospective study of diarrheal diseases in Venezuelan children to evaluate the efficacy of rhesus rotavirus vaccine.
The efficacy of a rhesus rotavirus vaccine (MMU 18006, serotype 3) against infantile diarrhea was evaluated by active home surveillance of a group of 320 children 1-10 months of age in Caracas, Venezuela. During a 1 year period following oral administration of vaccine or placebo under a double-masked code, over 600 diarrheal episodes were detected. Etiologic studies revealed that heat-stable toxin (ST) producing enterotoxigenic E. coli (ETEC) was the most common diarrheal agent detected (34%) followed by enteropathogenic E. coli (EPEC, 10.9%), heat-labile toxin (LT) producing ETEC (7.6%), rotavirus (6.9%), Cryptosporidium (4.8%) and Campylobacter (1.3%). ST-producing ETEC were also recovered from over 20% of control stool specimens obtained during diarrhea-free periods, whereas EPEC, rotavirus, Cryptosporidium, and Campylobacter were rarely detected in such control specimens. Rotavirus was responsible for about one-half of the more severe cases of diarrhea. Twenty-two of 151 infants who received placebo (14.6%) and eight of 151 receiving a 10(4) PFU dose of vaccine (5.3%) had rotavirus diarrhea during the follow-up period for an efficacy level of 64% against any rotavirus diarrhea. However, vaccine efficacy reached 90% against the more severe cases of rotavirus diarrhea and was noticeably high in the 1-4 month age group. Serotypic analysis of the rotaviruses detected suggests that the resistance induced by the vaccine was type specific since significant protection was only evident against serotype 3 rotaviruses. A 10(3) PFU dose tested initially in 18 children did not appear to protect against rotavirus diarrhea.
Perez-Schael
I
I
Instituto de Biomedicina, Universidad Central de Venezuela.
Garcia
D
D
Gonzalez
M
M
Gonzalez
R
R
Daoud
N
N
Perez
M
M
Cunto
W
W
Kapikian
A Z
AZ
Flores
J
J
D003168:Complement Fixation Tests; D003968:Diarrhea, Infantile / Q000382:microbiology / Q000469:parasitology / Q000517:prevention & control*; D004311:Double-Blind Method; D004341:Drug Evaluation; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D009500:Neutralization Tests; D011446:Prospective Studies; D011897:Random Allocation; D012401:Rotavirus / Q000276:immunology* / Q000302:isolation & purification; D022243:Rotavirus Vaccines; D014611:Vaccination; D014613:Vaccines, Attenuated; D014687:Venezuela; D014765:Viral Vaccines / Q000008:administration & dosage* / Q000009:adverse effects
D022243:Rotavirus Vaccines; D014613:Vaccines, Attenuated; D014765:Viral Vaccines; C052014:rhesus rotavirus vaccine