human respiratory syncytial virus / human orthopneumovirus (HRSV)

see also:

• viruses
• influenza
• https://www.rch.org.au/kidsinfo/fact_sheets/Respiratory_Syncytial_Virus_RSV/
• https://www.health.nsw.gov.au/Infectious/factsheets/Pages/Respiratory-syncytial-virus.aspx

• now renamed to human orthopneumovirus
• it is a negative-sense, single-stranded RNA virus of the family Pneumoviridae.
• HRSV is the most common cause of lower respiratory tract infections in children, and nearly all children will have been infected with the virus by 2–3 years of age and 2-3% will develop bronchiolitis for which it is the most common cause
• natural immunity following infection wanes over time resulting in the possibility of multiple infections
• young adults can be re-infected every five to seven years, with symptoms looking like a sinus infection or a common cold (although infections can also be asymptomatic)
• severe infections have increasingly been found among elderly patients

• incubation period is usually 4-5 days but may be 2-8 days
• spread is by droplets and direct contact - virus remains viable on hands up to 30 minutes or so, and on bench tops for up to 5hrs
• it tends to spread rapidly in childcare centres
• it can be spread to or from other primates
• illness lasts 2-8 days but symptoms can last 3 weeks
• most infections are mild URTIs
• may present as:
  • asymptomatic or common cold-like illness in healthy adults
  • bronchiolitis in infants
  • severe pneumonitis, particularly in neonates, the elderly or the immunocompromised
• it may precipitate asthma and otitis media
• it seems a rash appeared in about 1% of children with RSV subtype A and 10% with subtype B
  • the rash is mainly found on the trunk of the body, with fewer spots on the arms and legs, and usually lasts around five days
• it remains infectious for 3-8 days after onset of symptoms (and may be longer if immunocompromised)
• cough may persist for up to 4 weeks

• nasal swab for PCR or antigen detection tests (less reliable in adults than in children)

• supportive care
• CXR and basic blood tests if indicated
• supplemental oxygen as needed
• IV fluids as needed
• non-invasive ventilation as needed
• Rx bronchiolitis as needed eg. nebulized 3% saline
• Rx asthma as needed

• vaccination
  • the 1st vaccine for RSV, AREXVY, a protein-based vaccine, was approved in US in 2023 and in Aust for the over 60's in 2024
  • in Apr 2026, Aust Govt announced it will be free for those over 75yrs (over 60yrs for First Nations people)
• isolation and mask for infected cases who should avoid contact with infants, child care centres, the elderly or immunocompromised, but can usually go to kindergarten or school if well enough
• hand hygiene
• don't share drinks or cups
• clean any fomites such as toys with warm water and detergent
• no vaccine currently available but a new RSV vaccine was created in 2023 and is awaiting approvals
• palivizumab for preterm or high risk infants
  • monthly injections, which are begun just prior to the RSV season and are usually continued for five months