Two adults are now in the Hawke's Bay Hospital intensive care unit, alongside three children, after being struck down by respiratory syncytial virus.
The outbreak of RSV has been spreading throughout New Zealand since the transtasman border opened and clogging hospitals for about two weeks.
As of Thursday afternoon, there were 25 children in the Hawke's Bay Hospital children's ward, the majority with RSV or suspected RSV.
On Tuesday, Hawke's Bay DHB said RSV cases were continuing in children and increasing in adults.