398 - Trend in RSV Immunization

Publication Number: 2387.398

Sara Rizzuto Steinberg, NYP, katonah, NY, United States; Shetal Shah, Maria Fareri Children's Hospital at Westchester Medical Center, Syosset, NY, United States; Jasmin Cuevas, nyp, Tomkins cove, NY, United States; Nilanjana Banerjee, Maria Fareri Children's Hospital at Westchester Medical Center, Armonk, NY, United States; Muhammad TK. Zia, New York Medical College, Mohegan Lake, NY, United States

Background: Maternal RSV vaccination & infant RSV immunization reduce RSV infection-associated hospitalization. Rates of vaccine refusal are increasing nationally. Understanding factors associated with RSV refusal, maternal vaccination & infant immunization may inform vaccine counseling.

Objective: To determine rates & demographic factors associated with maternal RSV vaccination, infant immunization & refusal over two RSV seasons.

Design/Methods: Two-year prospective survey of mothers who delivered at a single-center in NY during the 2023-24 (Year 1) & 2024-25 (Year 2) RSV seasons. Data of dyads who received prenatal RSV vaccine/newborn immunization were compared to those of mothers who refused prophylaxis. Bivariate comparison & adjusted logistic regression determined factors associated with maternal vaccination, infant prophylaxis, or refusal.

Results: Of 784 dyads analyzed, 545 (70%, 545/784) received either prenatal RSV vaccine (29%, 227/784) or RSV immunization (41%, 322/784). Maternal vaccination increased from Year 1-Year 2 (p < 0.001). The percent of mothers who refused any RSV prevention (30%) was unchanged from Year 1 to 2. Characteristics of comparing mothers/infants based on RSV prevention status are seen in Table 1.
In adjusted analysis, dyads receiving any RSV protection exhibited higher odds of identifying as Hispanic [Odds Ratio (OR) and 95% Confidence Interval (CI) 2.1 (1.5-2.9)] & receiving Hepatitis B vaccine (OR 7.0, 95% CI 4.7-9.9). These mothers had lower odds of self-identifying as Non-Hispanic White (NHW) (OR 0.5, 95% CI 0.3-0.6) or education beyond high school (OR 0.7, 95% CI 0.5-0.9).
Among dyads who received any form of RSV protection, mothers who received maternal vaccination exhibited higher odds of advanced maternal age (>35 yrs) (OR 2.1, 95% CI 1.1-3.9), greater than high school education (OR 2.8, 95% CI 1.4-5.7) & NHW race (OR 2.8, 95% CI 1.9-3.9).
Of 239 mothers who refused RSV prevention, concerns were vaccine safety (41%), "too many vaccines" (17%) & novelty of this immunization (14.5%). The percentage of mothers concerned about vaccine safety increased from Year 1- Year 2 (26% to 55%, p< 0.0001). The percentage of mothers concerned about excessive vaccination (24% vs 11%, p < 0.01) or vaccine novelty (21% vs 9%, p < 0.05) decreased.

Conclusion(s): RSV refusal rates are stable, & maternal vaccination rates increased. Hispanic ethnicity and C/S delivery are associated with any RSV prevention. Among mothers opting for RSV prevention, NHW mothers, those of advanced maternal age & greater education exhibited higher maternal vaccination rates.

Characteristics of mothers receiving RSV prophylaxis compared to Refusers
*p < 0.05; **p < 0.001