BACKGROUND: Respiratory syncytial virus (RSV) is a common reason for 
hospitalization of infants. In clinical trials, palivizumab reduced RSV 
hospitalization rates for premature infants. The 2014 American Academy of 
Pediatrics clinical practice guideline advised against use of palivizumab for 
otherwise healthy infants ≥29 weeks' gestation. The aim of this study was to 
determine the effect of palivizumab administration on hospitalization rates for 
RSV and bronchiolitis without RSV diagnosis among infants 29 to 36 weeks' 
gestation who do not have chronic illness.
METHODS: Claims data were extracted from databases of 9 Texas Medicaid managed 
care programs. Eligible infants were 29 to 36 weeks' gestation, without claims 
suggesting chronic illness, and who were born between April 1 and December 31 of 
2012, 2013, and 2014.
RESULTS: A total of 2031 eligible infants of 29 to 32 weeks' gestation and 
12 066 infants of 33 to 36 weeks' gestation were identified; 41.5% of the 
infants 29 to 32 weeks' gestation and 3.7% of the infants 33 to 36 weeks' 
gestation had paid claims for dispensing of ≥1 palivizumab doses. Among the 
infants of 29 to 32 weeks' gestation, palivizumab dispensing was associated with 
reduced RSV hospitalization rates (3.1% vs 5.0%, P = .04) but increased 
hospitalizations for bronchiolitis without RSV diagnosis (3.3% vs 1.9%, P = 
.05). There were no significant differences by palivizumab administration status 
for the infants of 33 to 36 weeks' gestation.
CONCLUSIONS: Among infants 29 to 32 weeks' gestation without chronic illness, 
palivizumab use was associated with reduced RSV hospitalizations but increased 
hospitalizations for bronchiolitis without RSV diagnosis.