Chelsea training was reportedly canceled on Thursday after someone close to the squad complained of Coronavirus symptoms.
According to The Athletic, the story developed on Wednesday night, but the decision to cancel Thursday morning's training was reached before the team could turn up at the grounds.
The grounds were to be thoroughly cleansed, with the players expected in training on Friday as usual.
The Blues are preparing for a Premier League clash against Aston Villa on Saturday, with Lampard expected to give a detailed report on Friday during his pre-match conference.
The Premier League is slowly feeling the heat of the COVID-19 virus, which has hit a number of European leagues.
Leicester City manager Brendan Rodgers confirmed on Thursday that a few of his players were being observed after they showed signs and symptoms of the deadly virus.
"We had a few players that have shown symptoms and signs," Rodgers said.
"It would be a shame [if the Watford game were postponed], but the public's health is the most important in all of this," he added.
There is a growing feeling that the Premier League might follow in the footsteps of LaLiga and Serie A, which have all been suspended due to the virus.