Bronchiolitis-causing RSV virus has arrived early this year

A common winter virus that causes bronchiolitis in children and coughs and colds in adults has come early this year, according to the Public Health Agency (PHA).

The newly-published Influenza Weekly Surveillance Bulletin, the first of the season, shows respiratory syncytial virus (RSV) is circulating earlier than anticipated.

"An earlier start to the typical RSV season was observed, with positivity beginning to increase from week 25, 2021 (2.0%) and peaking in week 37 at 17.5%. In weeks 40 and 41, 313 samples were positive for RSV, with positivity decreasing in week 41 to 8.3% (7.5% in week 41, 2019-20).

READ MORE: Flu virus activity lower than two years ago but Influenza A and B strains are in circulation

Respiratory syncytial virus is circulating earlier than anticipated.

"The recent increase in testing in local HSCT laboratories should also be noted. The majority (72.6%) of RSV positive samples since week 40 occurred in children aged 0-4 years," the bulletin states.

The PHA says that because multiplex testing for SARS-CoV-2/Flu/RSV was introduced at the Regional Virology Laboratory from Week 34, 2021, and the local WHSCT lab in October 2021 an increase in flu and RSV testing should be expected.