(Reuters) - London's FTSE 100 suffered its biggest one-day fall in nearly four months as the coronavirus spread globally with death tolls more than tripling from last week, spooking investors about the potential financial hit to travel and China-exposed companies. The FTSE 100 index , which had recovered on Friday after the World Health Organisation issued a measured assessment of the virus, stumbled 2.3%. The midcaps slid 2.1%, their steepest one-day decline in more than a year.All but three..