Respiratory Syncytial Virus in Asia 2026: Why older adults and infants need protection now

Respiratory syncytial virus (RSV) has long been framed as a “pediatric virus,” but data from Asia and worldwide now make clear that it is also a major threat to older adults and people with chronic conditions. At the same time, powerful new prevention tools are emerging: long‑acting monoclonal antibodies for infants and several pre‑fusion (preF) RSV vaccines for adults and for use in pregnancy. The convergence of rising awareness, aging populations, and new products arriving in Asian markets makes 2026 a pivotal moment for RSV prevention in the region.

RSV is an enveloped RNA virus that infects nearly all children by 2 years of age and causes seasonal outbreaks of bronchiolitis and pneumonia. Severe disease in infancy is strongly associated with prematurity, congenital heart disease, chronic lung disease, and immunodeficiency, but a substantial proportion of hospitalizations occur in otherwise healthy term infants. In low‑ and middle‑income settings in Asia, RSV contributes meaningfully to infant and under‑5 mortality, often in environments with limited access to oxygen, intensive care, or pulse oximetry. Yet because RSV looks clinically similar to “routine bronchiolitis,” its contribution to mortality is often under‑recognized in routine statistics.

For older adults, RSV occupies a niche similar to that of influenza: it causes acute lower respiratory tract disease, can precipitate decompensation of heart failure or COPD, and leads to hospitalizations and deaths, especially in those ≥65 years or with multimorbidity. Recent Asian cohort and hospital‑based studies show RSV detection rates in older adults with acute respiratory illness that are comparable to, or occasionally higher than, influenza, with similar lengths of stay and need for intensive care. As populations in East, Southeast, and South Asia age rapidly, the absolute burden of RSV‑associated morbidity and health‑care use in older adults is expected to increase. However, RSV testing in adult wards is still infrequent, which means that much of this burden is invisible to clinicians and policymakers.

Historically, the absence of effective vaccines or broadly applicable prophylaxis has contributed to clinical fatalism around RSV: beyond supportive care, there was “nothing to do.” Palivizumab, a monthly monoclonal antibody, was restricted to a narrow group of high‑risk infants and was largely unaffordable at scale. This landscape has changed dramatically over the past three years. A long‑acting monoclonal antibody, nirsevimab, provides season‑long protection against RSV lower respiratory tract infection with a single intramuscular dose and has shown high efficacy and effectiveness in preventing medically attended infection and hospitalization in infants. Parallel to this, several preF‑based RSV vaccines have shown robust efficacy in phase 3 trials in older adults and in pregnant women (for infant protection), leading to regulatory approvals in multiple regions.

For Asia, several strategic questions now arise. First, what is the optimal strategy to protect infants: maternal vaccination in pregnancy, infant immunization with a monoclonal antibody, or a combined, risk‑stratified approach? Maternal vaccination has the advantage of leveraging antenatal platforms and protecting infants from birth without an additional infant visit. Monoclonal antibodies, in turn, can cover all infants regardless of maternal vaccination status, may be easier to align with birth or early‑postnatal contacts, and can be targeted to high‑risk infants entering a second RSV season. Each approach faces different challenges in Asia, where antenatal care coverage, timing of visits, and facility delivery rates vary substantially between and within countries. At the same time, monoclonals are significantly more expensive and may not be available in all markets.

Second, how should RSV vaccines be deployed for older adults in health systems where influenza and pneumococcal vaccination are still far from universal? PreF‑based vaccines have shown first‑season efficacy around 70–80% against RSV lower respiratory tract disease in adults ≥60 years, with clinically meaningful protection against hospitalization and severe outcomes and evidence of sustained, albeit waning, protection into a second or third season. For many Asian countries, the pragmatic path may involve integrating RSV vaccination into existing “respiratory vaccine” platforms for older adults and people with chronic disease—essentially building a combined respiratory vaccination offer (influenza, pneumococcal, COVID‑19, RSV) delivered through primary care, specialist clinics, or targeted campaigns.

Third, what are the equity implications? Many Asian countries have large urban–rural and public–private divides, with cutting‑edge biologics available in private hospitals long before they are adopted and reimbursed in public programs. RSV prevention for infants and older adults will only have a population‑level impact if it is accessible beyond affluent urban populations. For infants, this implies careful cost‑effectiveness work, assessment of competing priorities in already crowded immunization schedules, and consideration of co‑financing or phased introduction, starting with the highest‑risk groups. For older adults, it means acknowledging that vaccine delivery outside the traditional pediatric EPI platform remains a weak point in many health systems and will require deliberate investment and service redesign.

From a communication standpoint, RSV prevention in Asia will benefit from clear, consistent messaging that distinguishes between “immunity” and “protection.” Natural infection provides only partial and short‑lived immunity; repeat infections are normal, even in adults, and the goal of vaccination or monoclonal antibodies is not sterilizing immunity but reduction in severe disease, hospitalization, and death. Because the target groups include newborns and frail older adults, health literacy efforts must also address family decision‑makers and caregivers, not only the individual patient. Explaining that RSV vaccines for older adults and maternal RSV vaccines have undergone large, rigorous trials, and that safety is being closely monitored, will be critical to prevent spillover of generalized vaccine hesitancy from other domains.

In 2026, Asia stands at an inflection point. Several RSV products are in or approaching regulatory review in major markets, guidance on infant and older‑adult RSV immunization is emerging from global and regional expert groups, and local data on RSV burden in older adults are finally becoming available. The decisions that Asian countries make over the next few years—about whether, when, and for whom to finance RSV prevention—will shape RSV‑associated hospital and mortality curves for decades in societies that are simultaneously aging and urbanizing at unprecedented speed.

For a “Health Literacy Asia” audience, RSV offers a powerful case study: a once‑familiar but underestimated virus, transformed into a preventable cause of severe illness by advances in structural biology, monoclonal antibody engineering, and vaccine design. The challenge now is less scientific than political and organizational—how to ensure that these tools are deployed in ways that are equitable, cost‑effective, and trusted by the communities they are meant to protect.

By Chief Editor Joe Schmitt  – Health Literacy Asia