Visits to Emergency Departments for ILI
Emergency Departments in Maryland reported a total of 43,158 visits last week through the
ESSENCE surveillance system. Of those visits, 453 (1.0%) were visits for ILI.
Maryland Resident Influenza Tracking Survey (MRITS)
A total of 548 Maryland residents responded to the
weekly flu survey this week. Of those, 6 (1.1%) reported having an influenza-like illness last week.

Clinical Laboratory Influenza Testing
Twenty-six clinical laboratories reported 323 rapid influenza tests performed. Of those, 3 (0.9%) were positive for type B influenza. (Rapid influenza tests are not as accurate as PCR tests, particularly when influenza activity is low in the community. As a result, patients with a positive rapid test are not considered “confirmed” cases of influenza [for surveillance purposes] until the State Laboratories Administration reports a positive PCR test.)
State Laboratories Administration Influenza Testing
The DHMH Laboratories Administration performed a total of 13 PCR tests for influenza. One as positive for type B influenza. (Influenza tests performed at the State Laboratory are considered the gold standard of influenza laboratory testing for influenza surveillance purposes.)
Please note that these data do not include the recently reported type A (H3N2) influenza cases reported in the press release dated October 19, 2012.
Influenza-associated Hospitalizations
Hospitals in Maryland reported 1 influenza-associated hospitalization. (A person with an overnight hospital stay along with a positive influenza test of any kind, e.g. rapid test or PCR, is considered an “influenza-associated hospitalization” for purposes of influenza surveillance.)

Outbreaks of Respiratory Disease
No outbreaks of respiratory disease were reported to DHMH. (Disease outbreaks of any kind are reportable in Maryland. Respiratory outbreaks may be reclassified once a causative agent is detected, e.g. from ILI to influenza.)
National Influenza Surveillance:
Previous reports for this season: