This literature marketed report as received from an other health professional refers to 48 patients of unknown age. The patients were vaccinated with doses of ROTATEQ, oral on an unknown date. No other co-suspects were reported. No concomitant medications were reported. On an unknown date the patient experienced temporally associated acute gastroenteritis and hospitalized. The outcome of temporally associated acute gastroenteritis was unknown. Temporally associated acute gastroenteritis was related to ROTATEQ, Oral. The primary aim of study was to identify and characterize rotavirus isolates from infants who had recently been administered ROTATEQ, oral and who had subsequently presented at tertiary care facilities with any symptom of gastroenteritis. The secondary aim of this study was to identify any ROTATEQ, oral strains circulating in communities using the vaccine. Methods: Fecal samples (N = 61) from children who developed gastroenteritis following recent ROTATEQ vaccination were forwarded to the Surveillance Program. ROTATEQ-positive samples were genotype and regions of the VP3, VP4, VP6, and VP7 genes were sequenced. Also, 460 rotavirus-positive routine surveillance samples were analyzed by dot-blot Northern hybridization to detect ROTATEQ vaccine derived strains circulating in the community. Results: Sixty-one fecal specimens were collected between 1 July 2007 and 1 September 2010 from infants with temporally associated acute gastroenteritis after ROTATEQ vaccination. No sample tested positive for the presence of other enteric pathogens including parasites, Salmonella, Shigella, Campylobacter, Aeromonas, Plesiomonas, Yersinia, adenoviruses, and Norovirus. Forty-three samples were confirmed as rotavirus positive, and 30 were identified as containing wild-type rotavirus strains. Of the 13 samples identified as containing a strain from the ROTATEQ, oral, 2 samples contained a single vaccine strain (G1P[5]); 5 samples contained 2 vaccine strains, as shown by the simultaneous presence of P[8] and P[5] P genotypes; and 2 samples contained at least 4 of the vaccine strains. The remaining 4 samples contained single vaccine-derived (vd) G1P[8] (denoted vdG1P[8] hereafter) strains that were analyzed further. The remaining 18 samples tested negative for the presence of rotavirus. These samples could represent cases of diarrhea due to other causes. All samples exhibited a high degree of nucelotide homology (99.5% 100%) with the published ROTATEQ, oral sequences. All reassortant strains showed a high degree of nucleotide homology (99.6% 100%) to the G6P[8] strain. Therefore, it was concluded that the vdG1P[8] strains detected in samples from patients 2, 6, 7, and 9 were reassortants between the vaccine reassortant strain G1P[5] and the vaccine reassortant strain G6P[8]. Discussion: In this postlicensure study, the authors describe the identification of ROTATEQ vaccine derived strains temporally associated with postvaccine diarrhea in infants admitted to 3 pediatric hospitals. ROTATEQ vaccine strains were identified in 21.3% (13 of 61) of infants who developed diarrhea within 2 weeks of vaccine administration. Seven infants developed symptomatic excretion after the first dose of ROTATEQ and 4 patients developed symptomatic excretion after the second dose. One patient had severe combine immune disorder (SCID) and received the scheduled 3 vaccine doses and experienced mild gastroenteritis after the first dose, which worsened with subsequent doses. Although the length of time of ROTATEQ vaccine excretion is unknown for all but 1 of these patients, the length of time between vaccine administration and the infant presenting to tertiary care facilities with symptoms of gastroenteritis was known for 9 patients. With the exception of the SCID patient who presented 3 months after the final ROTATEQ dose, the infants in this study presented 12 days after vaccination. Of the 13 ROTATEQ-positive samples identified in infants, 4 excreted a vdG1P[8] vaccine-derived virus produced by reassortment between 2 of the vaccine strains, G1P[5] and G6P[8]. Sequence analysis of the VP7 and VP4 genes confirmed that the outer capsid genes were vaccine derived, and the ROTATEQ WC3 bovine backbone was confirmed by sequence analysis of the VP3 and VP6 genes. Among the 460 rotavirus samples collected from children with gastroenteritis admitted to hospital in states using ROTATEQ, 3 samples tested positive for ROTATEQ vaccine strains. The vaccination status of these individuals is unknown; however, 2 of the patients were 2 months of age and thus likely to represent cases where infants had been recently vaccinated, and community circulation of vaccine strains cannot be confirmed. CONCLUSION: Given the right set of circumstances, vaccine strains can cause disease in individuals with underlying medical conditions associated with immunosuppression. This study has documented a total of 16 cases of vaccine strains in children with diarrhea, with 6 of the cases involving reassortment events between 2 of the reassortant vaccine strains. While our study does confirm the reasortment between ROTATEQ vaccine strains can occur in postlicensure settings, it should be highlighted that these cases represent a very small proportion of all the individuals vaccinated. The risk posed by wild-type infection far outweighs the risks associated with the rare event of vaccine-associated disease. This is one of several reports received from the same source. Additional information has been requested.