[The new method for detecting the outbreak sign of MRSA]

Conventional outbreak detection laboratory-based made one unit from the beginning of the month to the end of the month, totaled and analyzed, cannot correctly detect outbreaks continued during two months. The real-time analysis (RTA) we devised adapts to methicillin-resistant Staphylococcus aureus (MRSA) and avoids the problems of conventional detection. RTA analyzes all data for the last 30 days when MRSA is newly isolated 48 hours or more after hospital admission. In the three years from April 2006 to March 2009, we compared the day and number of MRSA outbreaks newly isolated 48 hours or more after hospital admission in 572 subjects using the conventional method and RTA. We also calculated the RTA infection prevention effect. The number of outbreaks detected conventionally numbered 68 cases and those detected by RTA numbered 106 cases. The number of outbreaks newly detected by RTA numbered 38 cases in three years, averaging 4.3 days earlier than conventional detection using conventional method A an average of 15.7 days earlier than conventionally which totals for every end of the month using conventional method B. The effect of infection prevention in the change of RTA from conventional method A presumably decreases MRSA infection to 14-18 persons and it in the change of RTA from conventional method B decreases MRSA infection to 18-25 persons in one year. These results suggested that outbreak detection by RTA could help prevent MRSA outbreak and decrease MRSA infection frequency.