Respiratory syncytial virus: Are we making any progress?

RSV has a talent for showing up uninvitedlike that cousin who “just needs a place to crash for a few nights”
and then you find them reorganizing your pantry by vibes. For decades, respiratory syncytial virus (RSV) has been
a predictable troublemaker: it spreads easily, hits babies hard, can seriously sicken older adults, and usually peaks
when everyone’s already juggling flu season and whatever new cold is trending on campus.

The good news: yes, we’re making real progress. Not “we bought a new thermometer” progressactual, measurable,
public-health-level progress. In the last couple of years, the U.S. has rolled out vaccines for older adults, a maternal
vaccine to protect newborns, and long-acting antibody shots for infants. Even better, early real-world data suggest these
tools are lowering RSV hospitalizations in the youngest babiesthe group that historically ends up in the hospital the most.

Quick RSV refresher: what it is and why it’s a big deal

RSV is a common respiratory virus. For many people it behaves like a cold: runny nose, cough, congestion, fever, maybe wheezing.
Symptoms typically show up a few days after exposure (often around 4–6 days), and they can appear in stages instead of all at once.
Most infections resolve with time and basic supportive care.

But RSV is not “just a cold” for everyone. It can move into the lower airways and trigger bronchiolitis or pneumonia, especially in:

• Infants (particularly very young babies, who may show fewer “classic” cold symptoms and more breathing difficulty or feeding trouble)
• Older adults (RSV can be severe and can worsen chronic conditions)
• People with certain medical conditions (for example, chronic lung or heart disease, immune compromise)
• Residents of long-term care facilities (where respiratory viruses spread efficiently)

RSV also has a social life. It spreads through respiratory droplets and contaminated surfaces, and it circulates seasonally.
In the U.S., RSV often peaks in the cooler months, but timing has been disrupted in recent yearsmeaning planning for RSV prevention
is now less “set your calendar” and more “check your local forecasts.”

So… are we making progress? The answer is “yes,” and here’s why

For decades, RSV research kept running into the same wall: the virus is tricky, immunity can be incomplete, and earlier vaccine attempts
didn’t deliver the safe, durable protection scientists wantedespecially for the people who need it most.

What changed is a combination of better molecular science and better strategy. The modern RSV era is powered by a key insight:
the virus’ “fusion” protein (often called the F protein) is a top target for neutralizing antibodies, and the “prefusion” shape of that protein
is especially good at triggering strong immune protection. Once researchers learned how to stabilize that prefusion form, the whole field
moved fasterand suddenly RSV prevention started looking less like a wish and more like a product launch.

Progress #1: Vaccines for older adults (yes, really)

Older adults have always been a major RSV risk group, but public attention historically tilted toward babies. That’s changing.
The U.S. now has multiple FDA-licensed RSV vaccines for adults, and CDC guidance has evolved to focus vaccination where it helps most.

Who’s recommended to get an RSV vaccine?

Current CDC guidance recommends a single dose of an RSV vaccine for:

• All adults ages 75 and older
• Adults ages 50–74 who are at increased risk for severe RSV (for example, certain chronic conditions or living in a nursing home)

One dose is the current standardRSV vaccination is not considered an annual vaccine at this time. That matters for both planning and expectations:
you’re not signing up for a new yearly subscription (at least not yet).

Are these vaccines working in the real world?

Early real-world evaluations are encouraging. Large studies of adults tested for RSV have estimated strong effectiveness against RSV-associated
acute respiratory illness and serious outcomes like urgent care visits and hospitalization. Vaccine performance isn’t identical in every subgroup,
and effectiveness can be lower in people with immune compromise, but the direction is clear: these vaccines are reducing severe RSV outcomes.

What about safety?

Like all vaccines, RSV vaccines can cause short-term side effects (think sore arm, fatigue, mild fever). There has also been ongoing monitoring for
rare neurologic events such as Guillain-Barré syndrome (GBS). The signal appears uncommon, and public-health guidance continues to emphasize that
benefits outweigh risks for those most likely to be hospitalized from RSVespecially older adults and people with high-risk conditions.
The practical takeaway: vaccination decisions are best made with an informed, personalized conversation about individual risk.

Progress #2: Protecting babies before they get sick (maternal vaccine)

Newborns can’t raise their hands and request better immunity, so we borrow it for them. That’s the idea behind maternal immunization:
vaccinate the pregnant person so protective antibodies pass to the baby.

How maternal RSV vaccination works (in plain English)

CDC guidance recommends a single dose of the maternal RSV vaccine (currently Pfizer’s Abrysvo) during weeks 32–36 of pregnancy,
given seasonally (often September through January in most of the U.S.). The goal is to protect infants during their most vulnerable early months.
Additional doses aren’t recommended in subsequent pregnancies under current guidance.

This approach is a big deal because the highest RSV hospitalization rates historically cluster in the youngest infantsespecially the first couple of months
of lifewhen “just keep them away from germs” is both ideal and hilariously unrealistic.

Progress #3: Long-acting antibody shots for infants (the “instant defense” option)

Here’s where RSV prevention gets cool in a very science-y way: infants can be protected with long-acting monoclonal antibodies.
These are not vaccines. They don’t teach the immune system to make its own antibodies. Instead, they provide ready-made antibodies that can help
prevent severe RSV disease during a typical RSV season.

What’s recommended for infants and young children?

CDC guidance recommends an infant RSV antibody for infants younger than 8 months who are born during or entering their first RSV season,
especially if:

• The mother did not receive RSV vaccine during pregnancy, or
• The mother’s RSV vaccination status is unknown, or
• The baby was born within 14 days of maternal RSV vaccination.

The U.S. now has two long-acting infant antibody products:

• Nirsevimab (brand: Beyfortus)
• Clesrovimab (brand: Enflonsia)

Either product may be used for eligible infants in their first season (no preference for most infants). For certain children ages 8–19 months
entering their second RSV season who are at increased risk for severe RSV disease, CDC guidance recommends nirsevimab.

Do babies need both maternal vaccine and infant antibodies?

Usually, no. U.S. guidance generally recommends either maternal vaccination or infant antibody protection for most babies,
not both. Think of it as choosing the best tool for the situation rather than stacking every tool like a Jenga tower of good intentions.

Proof-of-progress: are hospitalizations actually dropping?

This is the question that matters. New interventions are exciting, but RSV doesn’t hand out participation trophieseither hospitalizations go down or they don’t.

Early U.S. surveillance analyses from the 2024–2025 respiratory virus season (the first season with widespread availability of maternal RSV
vaccination and long-acting infant antibodies) reported significantly lower RSV-associated hospitalization rates among younger infants
who were eligible for prevention products compared with pre-pandemic baseline seasons. Some analyses found particularly large reductions among the youngest infants.

A key nuance: RSV is still circulating, and some older infant/child age groups not eligible for these prevention tools saw higher hospitalization rates
in that season compared with earlier baselinessuggesting the season overall may have been more severe. That makes the reductions in younger infants
even more meaningful: the drop is less likely to be explained by “RSV was mild this year,” and more likely connected to targeted protection.

What progress doesn’t mean (yet)

RSV progress is realbut it’s not magic. Here are the gaps that keep RSV from being a “solved problem”:

1) Timing and seasonality are still messy

RSV used to be more predictable. Recent years have shown shifts in timing, which complicates when to vaccinate pregnant people and when to give infant antibodies.
Public-health guidance increasingly emphasizes seasonal administration and local patterns for a reason: RSV doesn’t always follow last decade’s calendar.

2) Uptake and access are the next bottleneck

New tools only work if people can get them. Early rollout challengeslike limited supply of certain infant antibody doses during the 2023–2024 seasonhighlighted
how demand, logistics, and insurance pathways can affect real-world protection. Supply expectations have improved, and pediatric guidance has suggested shortages are
not expected in upcoming seasons, but access remains a practical hurdle in many communities.

3) We still need durability answers

How long does protection last after adult vaccination? What’s the best strategy if someone is vaccinated once and remains high-risk in later seasons?
For infants, long-acting antibodies are designed to cover a typical season, but they aren’t meant to provide multi-year immunity. We’re in the “early innings” of
long-term durability data.

4) Safety monitoring is ongoing (as it should be)

Rare side effects can be hard to detect in clinical trials. Post-licensure surveillance is where we learn about unusual events at population scale.
The ongoing monitoring for rare neurologic outcomes after RSV vaccination in older adults is an example of the system working the way it’s supposed to:
detect signals, investigate them, and refine guidance.

Where RSV prevention is heading next

If the last few years were the “RSV breakthrough era,” the next few are likely the “RSV optimization era.” Expect progress in four directions:

• Sharper targeting: Better tools to identify who benefits mostespecially among adults 50–74 with mixed risk profiles.
• Streamlined infant protection: More consistent supply, clearer clinic workflows, and harmonized guidance as new products enter practice.
• Combination strategies: Research interest is growing in multi-pathogen approaches (because respiratory viruses like to travel in packs).
• Better treatment options: Prevention is winning the spotlight, but improved antivirals and supportive-care strategies remain important,
  especially for immunocompromised patients and hospitalized infants.

Bottom line: yes, we’re making progressand it’s measurable

RSV hasn’t disappeared, and it still causes serious disease. But compared with “we can only offer supportive care and hope,” today’s landscape is different.
We now have:

• Vaccines to reduce severe RSV in older adults
• Maternal vaccination to protect newborns during the highest-risk window
• Long-acting infant antibodies that provide season-long protection for many babies
• Early real-world signals showing fewer RSV hospitalizations in the youngest infants

That is progresspractical, evidence-based progress. RSV may still be that uninvited guest, but for the first time in a long time,
we’re not answering the door empty-handed.

Experiences from the real world: what “RSV progress” looks like up close

Statistics are great for policy decisions, but RSV is experienced one cough at a time. What does progress actually feel likein clinics, in homes,
and in the anxious space between “my baby is sniffly” and “do we need to go in right now”?

In pediatric offices, one of the biggest changes has been the conversation itself. For years, RSV prevention advice for newborns sounded like a nervous
weather report: “RSV season is comingwash hands, avoid crowds, keep sick visitors away.” All sensible, but not always doable. Now many clinicians describe
something new: a concrete plan. Parents of newborns are hearing options like, “You can protect your baby through maternal vaccination” or “Your baby may be eligible
for a long-acting RSV antibody shot.” That shiftfrom vague caution to actionable preventionreduces stress in a way that’s hard to quantify but easy to recognize.

Families often talk about RSV as a kind of emotional whiplash. A baby can go from mild congestion to labored breathing faster than adults expect, and first-time
parents may feel guilty for not noticing “the signs” soonereven though RSV symptoms can evolve in stages and can look like an ordinary cold at first. In that context,
prevention products aren’t just medical; they’re psychological relief. Parents frequently describe feeling more confident bringing their newborn to routine appointments,
meeting close family, or navigating daycare drop-offs with an older siblingbecause risk has been reduced, not eliminated, but reduced in a meaningful way.

Nurses and respiratory therapists often describe RSV surges as a seasonal strain on pediatric capacity. When hospital units fill, it’s not only about beds; it’s about
staffing, equipment, and the ripple effects on care for other conditions. In seasons where protection products are widely used, clinicians have reported seeing fewer
of the very youngest infants requiring intensive support. That doesn’t mean RSV disappearsolder babies and toddlers still get sick, and some seasons hit harder than others.
But the sickest cohort historically has been the youngest infants, and even modest reductions in that group can change the feel of a winter shift.

In older adults, the “experience” of RSV progress looks different. Many people over 50 have lived through decades of “get your flu shot, consider pneumonia vaccination,
and hope for the best.” RSV vaccination adds another layer, and for some it prompts a long-overdue check-in about respiratory health overall: asthma control, smoking cessation,
COPD management, and staying current on vaccines that reduce hospitalization risk. Clinicians often describe these visits as a two-for-one: RSV prevention plus a broader
tune-up that can lower the odds of severe outcomes from multiple respiratory viruses.

Public health departments and clinic administrators experience RSV progress in spreadsheets and supply chains. The earlier nirsevimab supply limitations created a new kind
of stress: having a powerful preventive tool but not enough product to cover every eligible infant immediately. That experience has pushed systems to improve forecasting,
ordering workflows, and communication so parents aren’t surprised at the pharmacy counter. Recent guidance suggesting shortages are not expected in upcoming seasons is
encouraging, and it reflects an important truth about modern immunization programs: science can move fast, but distribution has to keep up.

Finally, many families experience RSV progress through “near misses.” The baby who catches a cold in December but stays out of the hospital. The grandparent who gets a
respiratory illness but avoids pneumonia. No one throws a party for an illness that didn’t become severebut those quiet outcomes are exactly what successful
prevention looks like. In RSV’s case, progress isn’t dramatic; it’s fewer emergencies, fewer hospitalizations, and more ordinary winter days. And honestly, ordinary is
underrated.