Nirsevimab Immunization Expands to Protect Infants Against RSV in Chile

Chile is continuing its proactive approach to protecting infants from Respiratory Syncytial Virus (RSV) with the ongoing implementation of a national immunization strategy using Nirsevimab. Beginning March 1st, the program provides the preventative medication to all newborns, as well as infants born between October 1, 2025, and February 28, 2026, and high-risk children up to two years of age.

What is Nirsevimab and How Does it Work?

Nirsevimab is a single-dose, long-acting monoclonal antibody designed to prevent RSV infection, a leading cause of severe respiratory illness in infants. Research demonstrates its effectiveness in reducing the burden of care related to RSV at all levels, although its effectiveness decreases over time. At 150 days, it remains highly effective in preventing hospital admissions.

Implementation in the Atacama Region

The Atacama region has been at the forefront of this initiative, with the administration of Nirsevimab beginning in the maternity wards of hospitals in Copiapó and Vallenar. According to Bernardo Villablanca, Director of the Atacama Health Service (SSA), each newborn receives the medication alongside routine vaccinations. Over 444 infants and newborns in the region have been immunized, representing 36% progress as of March 20, 2026.

National Success and Impact

Chile’s commitment to RSV prevention has yielded significant results. During the 2025 campaign, the region surpassed the national goal of 80% coverage, and importantly, no deaths were recorded in the target population associated with RSV. Positive results were also seen in 2024, with no RSV-related deaths reported for two consecutive years. Studies show that Chile’s nirsevimab strategy significantly reduced RSV-related hospitalizations, including those requiring intensive care, and even saw reductions in all-cause lower respiratory tract infection hospitalizations.

Accessing Nirsevimab

There are two primary ways to access Nirsevimab in the Atacama region: through hospital maternity wards for newborns and at Primary Care vaccination centers (CESFAM) for infants, as well as through private sector providers with agreements with the Seremi de Salud.

Looking Ahead

The success of Chile’s Nirsevimab program serves as a model for other countries seeking to reduce the burden of RSV. Continued efforts to achieve high immunization rates will be crucial in protecting future generations from this potentially serious virus.