Overview of Influenza2010-2011

New York City Department of Health and Mental Hygiene

Thank You to

• All our partners who help with influenza surveillance.

• We know this presents a great burden for infection control staff and want you to know how much we appreciate your efforts.

• If there is ever anything we can do for you-call us at 212 788 -9830 or 347 396-2616

Influenza Surveillance at a Glance

• ILINet-network of providers that report visits for influenza-like illness

• Syndromic Surveillance-uses electronic data submitted by Emergency Departments-captures approximately 95% of all ED visits in the city

• Active Laboratory Surveillance-weekly phone calls to labs to obtain data on the number of influenza tests requested, the number positive by assay type, as well as data on other respiratory viruses circulating in the city.

• On-line Reporting (Reporting Central)

ILINet Surveillance in New York City, 2008-2011

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2009-10

Baseline

2010-2011

Influenza and RSV Testing, October 3, 2010 - May 7, 2011

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Number of Influenza A

Number of Influenza B

% Influenza

% RSV

What Should Acute Care Facilities Report

• Hospitalized cases of laboratory-positive influenza

• Pediatric deaths (under 19 years of age) due tosuspected or confirmed influenza * (Health Code)

• Laboratory confirmed influenza among residents of long-term facilities (Include only those patients who developed illness more than 48 hours after admission)

• Pregnant or post-partum women with influenza-associated critical illness or death

Influenza Reporting 2010-2011

• 34 acute care facilities (57% of total acute care facilities in New York City) ever reported.

• Mean # reports= 40• Range 1-340 reports.• As of 4/18/2011- 2 facilities submitted 340 and

206 reports- 39% of total.• 24% of facilities submitted 1-2 reports for entire

season.• 43% of facilities never reported.

Pediatric Deaths

• Pediatric deaths (under 19 years of age) due to suspected or confirmed influenza meeting the following criteria: – Sudden pediatric death from unknown cause, but thought

to be due to natural cause or  – Pediatric death with clinically compatible illness in which

there is a positive influenza test or  – Pediatric death from unknown, febrile respiratory illness

– Report online via Reporting Central (formerly known as e-URF)

– Report by phone to: – Bureau of Communicable Disease at 1-212-788-9830 or – NYC Office of the Chief Medical Examiner (OCME) at 212-447-2030

What Should Long-Term Care Facilities Report

– One or more laboratory-positive case of influenza or

– A cluster of influenza-like illness (2 or more cases) or 

– Any increase over the baseline level of febrile respiratory illness

• Report to NYSDOH via Nosocomial Outbreak Reporting Form (NORA)

• Notify NYC DOHMH Bureau of Communicable Disease at 1-212-788-9830 or 347-396-2616

Influenza Outbreaks in LTCFs

• Total 41 outbreaks (OB) Oct 2010 and April 21, 2011.• 24 (59%) OBs from 21 LTCFs identified before receipt of

a Nosocomial Report from the facility:– 21 (88%) outbreaks were first identified through

Reporting Central – 3 (12%) outbreaks identified though active laboratory

surveillance

– Of 21 OB facilities, five (24%) had never reported an influenza outbreak previously and six (29%) had last reported an outbreak

between 2002 - 2005.

Outbreak Management in LTCF

• In 8 of the 24 (33%) OBs, LTCF conducted prospective surveillance-no other cases in addition to the reported hospitalized case and therefore elected not to initiate antiviral prophylaxis

• 1 LTCF did not identify new cases but elected to initiate antiviral prophylaxis.

• 1 LTCF did identify other ill patients but did not initiate antiviral prophylaxis

• 14 OBs- surveillance by LTCF staff identified other ill patients. LTCFs initiated several measures including cohorting of patients, using droplet precautions, restricting movement off the floors and initiating antiviral prophylaxis, either unit or facility- wide.

Why Continue to Report?

• Influenza in older people may have an atypical presentation, it may not be easily recognized.

• Influenza in an LTCF setting may go undetected unless respiratory specimens are submitted for testing.

• Reporting of hospitalized patients with laboratory-confirmed influenza by acute care facilities allowed BCD staff to inform the respective LTCF and provide guidance on influenza outbreak management.

Why Continue to Report

• Mandated reporting of influenza in LTCFs as specified under NYS Public Health Law does not by itself guarantee compliance as some of these facilities had never before reported such an outbreak and needed guidance and reminders to do so.