Question 1

What is RSV?

Accepted Answer

Respiratory syncytial virus (RSV) is a highly contagious RNA virus that infects virtually every child at least once by age 2. In most children and adults, it causes a mild cold-like illness. However, in infants under 6 months, premature babies, immunocompromised individuals and adults over 60, RSV causes severe lower respiratory tract infection — bronchiolitis in infants, pneumonia in older adults — leading to 3.6 million hospitalisations and 100,000 child deaths per year globally.

Question 2

Why is RSV so dangerous for infants?

Accepted Answer

Infant airways are narrow — even mild inflammation (bronchiolitis) significantly increases airway resistance. Infants cannot effectively cough up mucus. Infants under 3 months lack maternal RSV antibodies (transferred in late pregnancy — reduced in preterm babies). Immature immune responses make containment of RSV replication less effective. The combination makes RSV infection in young infants potentially life-threatening — the most common cause of infant hospitalisation globally.

Question 3

What is nirsevimab?

Accepted Answer

Nirsevimab (Beyfortus) is a long-acting monoclonal antibody — a single injection given to infants before their first RSV season — that provides approximately 5 months of protection against severe RSV. In the MELODY clinical trial, it reduced RSV-related medically attended lower respiratory tract illness by 74.5% and hospitalisations by 77%. Unlike the previous RSV antibody (palivizumab), nirsevimab is for ALL infants — not just high-risk groups. FDA-approved August 2023; EMA-approved November 2022.

Question 4

What RSV vaccines are now available for adults?

Accepted Answer

Two RSV vaccines were approved for adults aged 60+ in 2023: abrysvo (Pfizer — prefusion F subunit; approved by FDA and EMA) and Arexvy (GSK — prefusion F subunit with adjuvant; FDA-approved). For younger adults and pregnant women: abrysvo was also approved for maternal vaccination (32-36 weeks of pregnancy) to protect newborns via passive antibody transfer — the first licensed maternal RSV vaccine. An mRNA RSV vaccine (mResvia, Moderna) was FDA-approved for adults 60+ in 2024.

Question 5

How is severe RSV in infants managed?

Accepted Answer

RSV treatment is supportive — there is no approved specific antiviral therapy. Management: oxygen supplementation for hypoxia; high-flow nasal cannula or CPAP for respiratory support; careful hydration (nasogastric or IV if too breathless to feed); monitoring for deterioration; and mechanical ventilation in severe cases. Antibiotics are not indicated unless bacterial co-infection is confirmed. Recovery is typically 7-14 days.

Question 6

Is RSV only a disease of infants?

Accepted Answer

No — RSV causes significant disease across the lifespan: adults aged 60+, particularly those with COPD, heart failure or diabetes, experience RSV pneumonia with mortality rates comparable to influenza. Immunocompromised individuals — transplant recipients, those on B-cell depleting therapies — face high RSV mortality. The global burden in older adults is estimated at 170,000 deaths per year — comparable to seasonal influenza mortality. This recognition drove the approval of adult RSV vaccines.

Question 7

Why was it so hard to develop RSV vaccines?

Accepted Answer

RSV vaccine development has a troubled history. A 1960s formalin-inactivated RSV vaccine enhanced disease severity in vaccinated infants — causing higher hospitalisation rates than controls. This discovery set the field back decades and instilled extreme caution. The breakthrough was understanding the importance of the RSV prefusion F protein conformation — the pre-fusion form is far more immunogenic and produces better neutralising antibodies than the post-fusion form. All modern RSV vaccines and antibodies target the prefusion F protein.

Question 8

What is the RSV access gap in LMICs?

Accepted Answer

RSV causes 95% of its severe disease and mortality in LMICs — yet all approved RSV prevention agents are priced for high-income markets. Nirsevimab costs approximately $100-500 per dose in different markets — far beyond LMIC budgets. GAVI has signalled commitment to RSV prevention but specific programmes and pricing are still being established. Maternal vaccination may offer a more affordable population-level strategy if vaccine prices can be reduced.

Question 9

How does RSV relate to asthma?

Accepted Answer

Severe RSV bronchiolitis in early infancy is the strongest risk factor for subsequent childhood asthma — with children hospitalised for RSV bronchiolitis having 2-4 fold higher rates of recurrent wheeze and asthma. The relationship is bidirectional and mechanistically complex: RSV may trigger airway sensitisation; or RSV may be more severe in genetically predisposed children who would develop asthma anyway. Preventing severe RSV with nirsevimab may reduce childhood asthma incidence — a key research question.

Question 10

How does GMJ News cover RSV?

Accepted Answer

GMJ News covers WHO RSV burden data, nirsevimab and adult vaccine approvals, GAVI RSV access plans, and the infant bronchiolitis management evidence base. RSV prevention is a priority for Georgian maternal and child health — relevant to PHIG's immunisation programme and the Georgian Medical Journal.

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