Holiday season has passed. Gatherings have slowed. But don’t let your guard down just yet — experts say we’re still in the midst of respiratory virus season. COVID-19, influenza and RSV — known to many working in infectious disease as the “Big Three” viruses — continue to sweep through Washington state and the U.S., keeping community transmission levels high and straining some health care facilities as a new COVID variant takes hold. There’s some good news: The fall rise of COVID hospitalizations has slowed and flu hospitalizations have declined in recent weeks, according to the most recent re…