The MTA unveiled a new ad campaign on Thursday urging passengers to refrain from boarding its subways if they are not feeling well.The MTA claims that sick passengers are the leading cause of its delays. In fact, representatives say they saw an increase in last year?s delays from 4,000 in 2006 to 6,000 last year.

According to the MTA, sick passengers often pull the emergency brake when they don?t feel well. This creates the delays.Many straphangers feel that the ad campaign won?t curb the problem. Their solution is to use common sense before boarding a train.The new ad will be placed on the walls of subway stations.