Immunization Against RSV Yields Significant Savings for Australia

A comprehensive immunization initiative targeting infants for respiratory syncytial virus (RSV) has proven to be a financial boon for Australia, resulting in an estimated savings of approximately $6.2 to $6.9 million in hospital expenses. This statewide program, which commenced in 2024, has led to a remarkable 57% reduction in hospitalizations in Western Australia (WA), as reported by health experts.

A recent narrative review published in the Medical Journal of Australia highlights the current landscape and future possibilities for RSV prevention in the country. RSV is a leading cause of acute lower respiratory infections, particularly affecting children under four years of age, who account for half of all RSV-related hospitalizations.

In November 2023, the Therapeutic Goods Administration (TGA) registered a long-acting monoclonal antibody, nirsevimab, designed to prevent RSV infections in children under the age of two. This was followed by the approval of a maternal vaccine, Abrysvo, in March 2024, aimed at preventing RSV infections in infants under six months.

The authors of the review characterize the introduction of these vaccines as a pivotal advancement in the fight against RSV. They emphasize that both nirsevimab and Abrysvo have shown significant potential in decreasing hospitalization rates and alleviating long-term healthcare costs associated with RSV infections among infants.

Western Australia has taken a leading role in implementing a statewide immunization program, which began in April 2024. Under this program, all infants born between October 1, 2023, and September 30, 2024, were eligible to receive nirsevimab through primary care services and birthing hospitals, including Aboriginal children and those with health conditions that heighten the risk of severe RSV disease.

Data indicates that about 71% of the infants eligible for nirsevimab received the vaccine between April and September 2024. Consequently, RSV-related hospitalizations in WA were significantly lower than anticipated, with a 57% reduction observed from May to December 2024. This translates to one hospitalization prevented for every 43 infants vaccinated, demonstrating the program's efficacy.

A contemporary case-control study revealed that nirsevimab was 86.4% effective in preventing RSV-related hospitalizations among infants in WA. Given that the costs for a single RSV hospital admission can range from $12,346 to $13,695, the prevention of approximately 505 admissions is likely responsible for the substantial savings achieved.

Looking ahead to 2025, Australia has established a national RSV prevention program, which includes free maternal vaccinations with Abrysvo and targeted infant protection using nirsevimab. Evaluating data from this national initiative will be crucial for assessing and enhancing the overall response to RSV prevention in the future.

The authors caution that successful implementation of the RSV prevention strategy will hinge on maintaining cost-effectiveness, ensuring parental acceptance and uptake of the vaccines, and providing access to high-risk populations, including First Nations children. They advocate for an evidence-based approach to resource allocation, tailored to meet the needs of vulnerable groups while maximizing health and economic benefits across the nation.