Transmission of Human Rhinovirus Genotypes among Childcare Attendees
Methods: Between 2/2006 and 5/2009, children enrolled at three childcare facilities on a military base in Washington State between the ages of five weeks to 30 months were monitored for respiratory illness. Up to 71% of children in each classroom were enrolled. Mid-nasal swabs were collected at the time of respiratory illness and weekly until symptoms resolved and from a subset of asymptomatic children at enrollment. Samples were tested for HRV by real-time reverse transcriptase polymerase chain reaction. Sequencing was conducted targeting the 5’ non-coding region.
Results: HRV was detected in 360 samples from 160 children during 250 illnesses and from 74 of 141 swabs from 127 asymptomatic subjects. Of these, 289 (67%) specimens were successfully sequenced, including 66 unique genotypes. HRV-A, HRV-B, and HRV-C were detected in 170, 15, and 104 samples, respectively. Up to five distinct genotypes circulated in a single classroom during a two-week period. We observed HRV genotype clustering in individual classrooms. One HRV-A genotype was detected in 25 patients located in nine classrooms over 107 days. This HRV-A genotype circulated among four (44%) study participants in one room over 15 days, three (27%) participants in a second room over seven days, and three (17%) participants in a third room over three days. Within 14 days of initial detection, a separate HRV-A genotype was detected in seven (30%) enrollees located in a fourth room. Four days after initial detection, a HRV-C genotype was detected in four (44%) children in a fifth room. A different HRV-C genotype was found in three (15%) participants in the third room within a two-day period.
Conclusion: HRV-A and C were the most common species detected in symptomatic childcare attendees. Diverse HRV genotypes circulated within childcare facilities, clustering in individual classrooms during short time periods. Infection control and prevention should target these settings to reduce transmission.
E. K. Martin,
H. Y. Chu, None
M. Fairchok, None
E. T. Martin, None
J. A. Englund, Gilead: Consultant and Investigator, Consulting fee and Research support
Chimerix: Investigator, Research support
Roche: Investigator, Research support
GlaxoSmithKline: Consultant, Investigator and Member, DSMB (DataSafety Monitoring Board), Consulting fee, Payment for DSMB participation and Research support
Ansun Biopharma: Investigator, Research support