Levels of the vomiting bug norovirus are now higher than in previous years, figures show.
New data from Public Health England (PHE) shows there have been 1,704 cases of norovirus in England confirmed by laboratory testing so far this season, which is 9% higher than the average for the same period over the last five years.
The figure is also 55% higher than the same period last year, although last winter saw unusually low levels of norovirus.
Overall, in the last two weeks of November, there were 14 outbreaks of norovirus in hospitals, all of which led to ward closures or the closure of bays.
In total this season, there have been 105 hospital outbreaks reported.
The number of laboratory reports of the bug rotavirus this season is 938, which is also 9% higher than the average for the same period from 2003 to 2013.
Julia Scott, chief executive of the College of Occupational Therapists, said: "The rise in norovirus infections highlighted in today's figures means that it is vital the NHS does everything it can to prevent unnecessary admissions to hospital and to ensure that patients can go home as soon as they are medically fit.
"Delayed discharges increase the chance that someone who could go home may contract norovirus and become sicker than they were on admission."