Decline in Varicella-Related Ambulatory Visits and Hospitalizations in the United States Since Routine Immunization Against Varicella

Division of Infectious Diseases, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
The Pediatric Infectious Disease Journal (Impact Factor: 2.72). 11/2009; 29(3):199-204. DOI: 10.1097/INF.0b013e3181bbf2a0
Source: PubMed


Widespread varicella vaccination has led to substantial decreases in varicella-related mortality and hospitalizations. The effect of the vaccine on ambulatory care utilization is poorly defined.
To determine trends in varicella-related ambulatory care and hospital discharges before and after vaccine licensure.
Estimates of varicella-related ambulatory and hospital discharges were calculated for the pre- (1993-1995) and post- (1996-2004) vaccine licensure periods using the National Ambulatory Medical Care Survey, National Hospital Ambulatory Medical Care Survey, and National Hospital Discharge Survey.
Ambulatory and hospital discharge rates for varicella.
The rate of varicella-related ambulatory discharges decreased by 66% from 106.6 per 100,000 (95% confidence interval [CI]: 80.5-132.6) in the prelicensure period to 36.4 per 100,000 population (95% CI: 29.3-43.5) in the post-licensure period (P < 0.001). The decrease was significant across all age groups <45 years, with the greatest reduction (98%) occurring among patients 0 to 4 years of age. The incidence of varicella-related hospital discharges decreased by 53% from 30.9 per 100,000 (95% CI: 24.4-37.3) to 14.5 per 100,000 population (95% CI: 12.1-16.8; P < 0.001). This difference was significant among patients <14 years of age. Rates of varicella-related ambulatory discharges decreased significantly for both whites and non-whites in the postlicensure period, but postlicensure ambulatory discharge rates remained higher for non-whites than for whites. Decreases in varicella-related hospital discharges were statistically significant for whites and non-whites. Racial differences in the incidence of varicella-related hospital discharges also persisted following vaccine licensure.
Varicella-related ambulatory visits and hospitalizations have decreased significantly in the period after licensure of the varicella vaccine.

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Available from: Sarah Wood, Apr 07, 2015
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    • "Moreover, during the first decade after varicella implementation a significant decrease in varicella associated morbidity , hospitalization and mortality were noted [Davis et al. 2004; Marin et al. 2011; Nguyen et al. 2005; Shah et al. 2010; Zhou et al. 2005]. Ambulatory visits due to varicella significantly decreased by 66% from 106.6 to 36.4/100,000 population and as expected this was mostly evident in the age group mainly affected, i.e. young children 1–4 years old [Shah et al. 2010]. Moreover, hospitalization rates decreased significantly [Dubos et al. 2007; Reynolds et al. 2008; Zhou et al. 2005]. "
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