The FTSE 100 index of blue-chip companies dipped 0.2pc and the midcap index was lower by 0804 GMT.
The drop was consistent with Asian markets, where most indexes were down, after reports the coronavirus had killed more than 900 people, surpassing the death toll of the 2002-2003 SARS epidemic.
But NMC Health snapped a five-day losing streak, putting it on course for its best day since December, after it said it has got highly preliminary approaches from Kohlberg Kravis Roberts and GK Investment regarding possible offers.