Respiratory Syncytial Virus (RSV) infects the windpipe, causing croup in the smallest breathing tubes, causing bronchiolitis in the lungs, and causing pneumonia.
RSV causes a high disease burden for infants globally. Virtually all children will be infected with RSV by 2 years of age.
Every year, RSV causes 33 million episodes of severe respiratory infection in children under 5 years old. It is the leading cause of paediatric hospitalisations (3.6 million per year).
About 101,000 children die from RSV infection each year and half of them are below 6 months old.
98 per cent of RSV deaths occur among children in Low and Middle Income Countries (LMIC). Many children in low-income economies never make it to a hospital. Four times as many children die from RSV in the community than in the hospital.
No other virus, including influenza, causes this much damage to babies.
In Malaysia, RSV was the predominant virus, responsible for 70.6 per cent of all laboratory-confirmed viral LRTIs in children aged ≤5 years over the 26-year study period (1982 to 2008).
RSV-infected children below 2 years old had a high hospitalisation rate of 84.5 per cent.
69 out of 450 (15.3 per cent) children admitted into Tuanku Jaafar Hospital in Seremban from 2008 to 2013 with RSV needed intensive care, and 1.6 per cent (7/450) died.
The case fatality rate (CFR) is five times higher than in developed countries (0.3 per cent).
There is no specific treatment for RSV apart from supportive therapy with intravenous fluids, oxygen, empirical antibiotics and respiratory support in the intensive care unit.
The burden and cost of RSV disease is very high in LMICs. Averting this cost and burden through RSV immunisations could have large health impacts and save significant healthcare resources.
Since 1960s, researchers have explored various vaccines or options to prevent RSV.
Until 2022, Palivizumab, was the only licensed mono-clonal antibody (mAb) for prophylaxis against RSV. It is however a short acting mono-clonal antibody and require five monthly injections to prevent 55 per cent of RSV disease.
It is only indicated in premature infants and those with heart conditions and chronic lung diseases. The majority of infants with RSV are term infants.
In 2023, Nirsevimab, a long-acting (mAb) was licensed. It is 83.2 per cent effective at preventing RSV related hospitalizations in the first 5 months of life.
Real world experience showed that Nirsevimab is 82-98% effective at preventing RSV related hospitalisations and 70-90% ICU admissions.
Also in 2023, a maternal vaccine, given during the third trimester could prevent RSV in the first six months of life, when they are most vulnerable. The vaccine efficacy was 81.8 per cent for the first three months of life and 69.4 per cent for the first six months.
Now we are spoilt for options to prevent this once deadly disease in infants!
Dr Musa Mohd Nordin and Dr Husna Musa are paediatricians.
- This is the personal opinion of the writer or publication and does not necessarily represent the views of CodeBlue.
