RSV and Bronchiolitis: What Parents Need to Know This Winter
Quick answer
Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis, a chest infection that mainly affects babies under two. The 2026 RSV season in South Africa started in week 11 (9 March), roughly four weeks later than average, and it's running alongside an unusually early flu season. Most babies recover at home with supportive care. No medicine shortens the illness, and antibiotics don't help because RSV is a virus. This article covers what bronchiolitis looks like, what helps and what doesn't, red flags that need urgent care, and the new RSV prevention options (nirsevimab and the maternal Abrysvo vaccine) now available in South African private pharmacies.
Key points
- RSV is the leading cause of bronchiolitis in SA infants, and the 2026 season started on 9 March, about four weeks later than average
- Babies under 6 months are at highest risk of severe disease, especially those who were premature, have heart or lung conditions, are HIV-exposed, or are not breastfed
- Most bronchiolitis is managed at home with fluids, nasal saline, small frequent feeds, and careful monitoring
- Bronchodilators (like salbutamol), steroids, and antibiotics are not recommended for routine bronchiolitis because the evidence shows they don't help
- Two new prevention options are available in SA private pharmacies in 2026: nirsevimab (a single injection for the baby) and Abrysvo (a maternal vaccine given in late pregnancy)
- Severe bronchiolitis in infancy is linked to a higher risk of recurrent wheezing and asthma later in childhood
What is RSV and bronchiolitis?
Respiratory syncytial virus (RSV) is a common respiratory virus that causes cold-like symptoms in older children and adults. In babies and toddlers, though, it often travels deeper into the lungs and causes bronchiolitis, which is inflammation of the small airways called bronchioles.
Bronchiolitis is different from a cold (which affects mainly the nose and throat) and from pneumonia (which is infection of the lung tissue itself). In bronchiolitis, swelling and mucus block the tiniest airways, making it harder for a baby to breathe and feed. This typically happens in the first year or two of life, when those airways are naturally narrow.
RSV isn't the only virus that causes bronchiolitis (flu, parainfluenza, rhinovirus, and human metapneumovirus can all do it), but RSV is by far the most common cause in South African infants. Hospital data from Johannesburg found RSV in about half of moderate-to-severe bronchiolitis cases, and Cape Town data shows that about 31% of hospitalised children under 13 with lower respiratory tract infection test positive for RSV. In infants under 3 months admitted with such infections, half test positive for RSV.
The 2026 RSV season in South Africa
The National Institute for Communicable Diseases (NICD) declared the start of the 2026 RSV season on 30 March, confirming that it began in week 11 (the week starting 9 March). This is about four weeks later than the historical average, but similar to when the 2025 season started.
This year has an unusual twist: the influenza season began in the same week. Two respiratory virus seasons running at once means clinics and hospitals are seeing more sick children than usual, and some families are dealing with successive illnesses as one virus passes through and another arrives.
For the Western Cape and the Garden Route, RSV peak months are typically March and April, with roughly 89% of cases occurring between February and July. By early April 2026, national surveillance was detecting RSV in about 27% of tested samples, and the season was still climbing. This is the stretch of the year when paediatric admissions for breathing difficulty rise sharply.
Who is most at risk
The single most important risk factor is simply being young. Babies under 6 months old account for most RSV hospitalisations in SA. Infants under 3 months are at highest risk of severe disease.
Beyond age, the NICD and local research consistently highlight the following as risk factors for severe RSV:
- Prematurity, particularly if born before 32 weeks
- Chronic lung disease, which is common in very premature babies
- Congenital heart disease
- Neurological conditions affecting breathing or swallowing
- Immune deficiency, including HIV infection and HIV exposure
- Not breastfeeding
- Age under 6 months
In SA specifically, HIV-exposed babies (HIV-negative but born to HIV-positive mothers) have increased risk, and HIV-infected infants have the most severe disease. This reflects SA's still-significant paediatric HIV exposure and is one reason we pay extra attention to breathing patterns in HIV-exposed infants during RSV season.
Supportive care at home
The overwhelming majority of bronchiolitis cases are managed at home. Here is what actually helps.
Feeding and fluids
Offer smaller, more frequent feeds. A blocked nose makes it hard for a baby to feed in long stretches, but short feeds every one to two hours work well. Continue breastfeeding. Watch wet nappies as your hydration gauge: fewer than four wet nappies in 24 hours is a sign to seek help.
Clearing the nose
Saline drops or saline spray into each nostril before feeds and before sleep, followed by gentle bulb suction if mucus is visible, can make a meaningful difference. Over-suctioning irritates the nose, so limit it to before feeds and sleep rather than constantly.
Positioning
Keep your baby slightly upright during feeds and for 30 minutes after. The safest sleep position for any infant under one year remains flat on the back on a firm surface, not on pillows or inclined surfaces, even if they have a cough.
Air quality
Avoid cigarette smoke, wood-fire smoke, and strong fumes. Babies exposed to smoke have more severe bronchiolitis and longer illnesses.
Fever and discomfort
Paracetamol in weight-based doses helps with fever and discomfort. Ibuprofen is safe from three months. Do not use aspirin in children.
If your baby needs a clinic visit for breathing concerns, bring the Road to Health Booklet (RtHB). The RtHB gives the clinician a full picture of weight gain, feeding history, and immunisation status across any public or private visits so far, which shapes treatment decisions especially for young infants and premature babies.
Treatments that don't help
A lot of things have been tried for bronchiolitis over the decades, and most have been shown not to work. South African, European, and American guidelines converge on the following.
Bronchodilators (salbutamol)
Salbutamol (the medication in the blue asthma inhaler) does not help most bronchiolitis cases. It doesn't improve oxygen levels, reduce admissions, or shorten illness. It can cause rapid heartbeat and tremor in small babies. Guidelines now recommend against routine use, though a paediatrician may trial it in specific situations where underlying reactive airway disease is suspected.
Steroids
Oral or inhaled steroids don't shorten bronchiolitis or reduce admissions, and are not routinely recommended.
Antibiotics
Bronchiolitis is a viral illness. Antibiotics don't treat it. They're only indicated if there's clear evidence of a bacterial complication like middle ear infection or bacterial pneumonia.
Chest physiotherapy
Shown not to help in uncomplicated bronchiolitis and no longer routinely recommended.
If your doctor isn't prescribing these, it's not because they're holding back. It's because research consistently shows they don't work and can cause side effects.
Red flags: when to seek urgent care
Call 10177 or go to the nearest emergency department immediately if your baby:
- Is breathing very fast (more than 60 breaths per minute in babies under 2 months, or more than 50 in older infants)
- Has chest or neck retractions, where the skin pulls in with each breath
- Has blue or pale lips, tongue, or fingernails
- Has pauses in breathing (apnoea) of more than 10 to 15 seconds, especially in young infants
- Is grunting with each breath or has nostrils flaring with effort
- Is refusing to feed or drinking less than half of usual amounts
- Has fewer than four wet nappies in 24 hours
- Is very sleepy, floppy, or unusually hard to rouse
- Is worsening after seeming to improve
Don't wait for all of these to appear. Any one of them is a reason to get medical help straight away.
Oxygen saturation below 90% on a pulse oximeter is a common admission threshold in SA district hospitals. Some clinics and GP practices have pulse oximeters and can measure this during a consultation.
In this guide
Prevention: nirsevimab and maternal RSV vaccine now in South Africa
Two significant developments have landed in the South African private sector for the 2025-2026 RSV season.
Nirsevimab (long-acting monoclonal antibody)
Nirsevimab (sold as Beyfortus) became available through SA private pharmacies in 2025-2026. It's a single injection that gives the baby ready-made antibodies against RSV, protecting them for about five months. It can be given either as a birth dose for babies born during or just before the RSV season, or as a single dose before the season starts for older infants still in their first year. Infants at high risk of severe disease may receive another dose before their second RSV season.
In clinical trials, nirsevimab reduced RSV-related hospitalisations by 65% to 82% in healthy infants. It is a one-dose alternative to the older monthly palivizumab injection and is expected to become much more widely used.
Abrysvo (maternal RSV vaccine)
Abrysvo is a vaccine given to pregnant women between 28 and 36 weeks of pregnancy. It stimulates the mother to produce RSV antibodies that cross the placenta and protect the newborn during the first months of life, exactly when RSV is most dangerous. It's available in SA private obstetric and GP practice. This is the recommended option if a mother wants her newborn protected from birth and prefers not to inject the baby directly.
Palivizumab
The older monthly monoclonal antibody (Synagis) has been available in SA for some time, but it's expensive and requires an injection every month from February through June. It's generally reserved for very high-risk infants (extreme prematurity, significant chronic lung disease, haemodynamically significant congenital heart disease), and in private practice has largely been overtaken by nirsevimab.
Public sector
RSV maternal vaccination for the public sector is being considered by the NDoH but is not yet available. EPI-SA does not currently include any RSV-specific prevention. This is an area worth watching over the next one to two years.
At NeoHealth we can advise on whether your baby is a good candidate for nirsevimab, and we can administer Abrysvo in the correct pregnancy window. Please raise it at your next antenatal visit or at your baby's routine well visit.
The long view: bronchiolitis and later asthma
Parents whose child has had a serious bronchiolitis episode often ask whether it means asthma is coming. The honest answer is: possibly, depending on several factors.
Research shows a consistent pattern. Children hospitalised with bronchiolitis have about three times the risk of recurrent wheezing at ages 2 to 4 years compared to children without such a history. A large meta-analysis showed children with RSV lower respiratory tract infection had roughly four times the odds of developing asthma later. The Drakenstein Child Health Study, following 1,000 mother-child pairs near Cape Town, has shown similar patterns in SA infants.
The relationship is complex. It's not entirely clear whether severe bronchiolitis causes lasting changes to the airways, or whether babies who are destined to have asthma are simply more likely to have severe bronchiolitis (their airways may already be different before any infection). Either way, knowing the history helps us monitor for wheezing patterns as the child grows, and start asthma treatment promptly if it's needed.
One hopeful note: if new prevention strategies like nirsevimab reduce severe RSV infections, we may also see reductions in childhood wheezing and asthma. Early data is encouraging, and longer-term studies are underway.
Important: This article provides general medical information and is not a substitute for personalised medical advice. If you have specific concerns about your baby's breathing or feeding, please book a consultation with your GP or go to a casualty unit. In medical emergencies, call 10177 or visit your nearest emergency facility.
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Frequently Asked Questions
How long does bronchiolitis last?
Most babies improve over 7 to 10 days, with the worst symptoms in days 3 to 5. The cough can linger for 2 to 4 weeks. If symptoms are worsening rather than improving after day 5, or new symptoms appear (high fever, faster breathing), come back to the clinic.
My baby has a runny nose and a cough but is feeding well. Is this bronchiolitis?
Probably not. Bronchiolitis typically comes with fast or laboured breathing, wheezing, and difficulty feeding. A happy baby with a runny nose and a mild cough is more likely just to have a cold. Watch for changes in breathing or feeding, and come back if either worsens.
Can my baby catch RSV again?
Yes. Immunity after RSV infection is incomplete and short-lived, so children (and adults) can be reinfected. Second infections are usually milder, but high-risk infants can still have serious second infections.
Should I ask about nirsevimab for my baby?
It's worth discussing with your GP or paediatrician, particularly if your baby will be under 8 months old during the RSV season, or has risk factors for severe disease (prematurity, chronic lung or heart conditions, HIV exposure). Cost is a consideration for many families. Maternal Abrysvo during late pregnancy is an alternative that covers the first months of life.
Is it safe to take my baby to crèche during RSV season?
Crèche increases exposure, but avoiding all infection isn't realistic for most families. For babies under 6 months or with significant risk factors, delaying crèche entry or keeping them home during peak weeks is reasonable. Universal measures like handwashing, keeping unwell children at home, and continuing to breastfeed where possible all reduce risk.
My baby had bronchiolitis and now wheezes with every cold. Does she have asthma?
Recurrent wheezing with viral infections is common after bronchiolitis and doesn't necessarily mean asthma. Many children outgrow it by school age. If wheezing is severe, frequent, or interferes with sleep or feeding, an assessment is worth doing. Asthma can be diagnosed and treated from about age two onwards.
Does steam, camphor rub, or onion in the room help?
Steam has no evidence of benefit for bronchiolitis and causes burns in children every year. Camphor and menthol rubs like Vicks are not recommended in babies under two years (the product itself says this). Home remedies like onions in the room have no evidence base. Saline, hydration, upright positioning during feeds, and monitoring for red flags are what actually work.
How do I know if my baby is breathing too fast?
Count the breaths for a full minute while your baby is calm and resting (not crying). Watch the chest or tummy rise and fall. Over 60 breaths per minute in a baby under 2 months, or over 50 in an older infant, is concerning and worth a clinic visit.