Table 4 Administration strategies for protecting vulnerable populations in Italy

Protecting infants

The efficacy and safety of the mAb nirsevimab and the maternal vaccine RSVPreF are similar. Generally, infants should be passively immunized with one of these strategies, but in rare circumstances certain infants may benefit from a dual approach.

Maternal RSV vaccination

All pregnant women are eligible for vaccination, except immunocompromised individuals; in women at high risk of preterm delivery, delay administration until after 32 weeks of gestation as a precautionary measure while awaiting clarification regarding the potential risk of premature birth. The need for revaccination with subsequent pregnancies has not been established.

Administer a maternal RSV vaccine between gestational weeks 24 and 36, according to local recommendations. Follow a year-round administration strategy given that RSV circulation at the time of delivery may not be predictable; seasonal administration may miss opportunities for protection, whereas a year-round strategy – provided it’s feasible and cost-effective – may maximize the population benefits.

• Infants born < 2 weeks after maternal vaccination should be considered at risk of limited protection and hence eligible for nirsevimab. Infants at high risk for severe RSV disease^a born out of season to vaccinated mothers should also receive nirsevimab before the start of their next RSV season.

Nirsevimab administration

• Infants born at the start or during the RSV season who have not been passively immunized through maternal vaccination should receive nirsevimab before leaving the maternity ward.

• Infants born after the RSV season who have not been passively immunized through maternal vaccination should receive nirsevimab at the beginning of the next RSV season.

• Infants at high risk for severe RSV disease^a should also receive nirsevimab before the start of their second RSV season.

Protecting adults age ≥ 60 years and adults of any age with high-risk comorbidities^b

The RSVPreF and RSVPreF3 vaccines have similar efficacy and safety, and both provide some protection for at least two seasons.

• Eligible adults should receive one of these vaccines at any convenient time in the routine immunization schedule; whenever possible, schedule this vaccination before the start of RSV season.

• Evidence shows protection for at least two seasons. Ongoing studies will determine the duration of effective protection, potential usefulness of revaccination and optimal vaccination interval.