DEPARTMENT OF HEALTH AND MENTAL HYGIENE. nyc.gov/health

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1 THE CITY OF NEW YORK DEPARTMENT OF HEALTH AND MENTAL HYGIENE Michael R. Bloomberg Mayor Thomas R. Frieden, M.D., M.P.H. Commissioner nyc.gov/health 2009 New York City Department of Health and Mental Hygiene (NYC DOHMH) Health Alert #11: Swine Influenza Update Please distribute to staff in the Departments of Critical Care, Emergency Medicine, Family Practice, Geriatrics, Internal Medicine, Infectious Disease, Infection Control, Pediatrics, Neonatal Units, Nurseries, Pulmonary Medicine and Laboratory Medicine April 25, 2009 PLEASE NOTE: This is a rapidly evolving situation. This alert provides interim guidance. Guidance is likely to change in the upcoming days and weeks as more information becomes available. Swine influenza is suspected as the cause of a large outbreak of influenza A at St. Francis Preparatory High School in Queens. Specimens obtained from students at the school have been confirmed as influenza A, and are unsubtypeable as either H1 or H3 at the NYC Public Health Laboratory. This meets the case definition for probable swine influenza (see CDC case definitions below). o To date, all illnesses appear to have been mild and no cases have been hospitalized. o Samples are being sent to CDC tonight to determine if this outbreak is due to swine influenza. Results will be available tomorrow (Sunday). o At this time, we are recommending antiviral treatment with oseltamivir or zanamavir as follows for persons associated with the school: Severe influenza-like illness (ILI) or other severe febrile respiratory illness in a student, teacher, staff, or in any close contacts (e.g., household) of someone who attends or works at the school. For patients with mild illness, treatment is only recommended for people who also have underlying conditions that increase the risk for more severe illness due to influenza (listed below). Mild illness should be treated only if treatment can be started within 48 hours of symptom onset. o At this time, prophylais is only being recommended for the following contacts of ill persons associated with the school: Healthcare workers who provided care to ill patients, and who either were not using or had a breach in appropriate personal protection when caring for patients or obtaining specimens Asymptomatic household and other close contacts of ill persons who are at higher risk for complications of influenza (listed below). Reporting and management of other NYC hospitalized patients with severe, uneplained febrile, respiratory illness: o Immediately report all patients with severe, uneplained febrile respiratory illness to the Provider Access Line at o Test patients with severe febrile respiratory illness for influenza A using a commercially available rapid test, PCR or immunofluorescence test (e.g., DFA or IFA). Categories of urgency levels for NYC DOHMH Broadcast Notification System: Health Alert: conveys the highest level of importance; warrants immediate action or attention Health Advisory: provides important information for a specific incident or situation; may not require immediate action Health Update: provides updated information regarding an incident or situation; unlikely to require immediate action

2 o Personal protective measures should be taken by medical personnel caring for or obtaining specimens from patients being tested for influenza or who have suspected, probable or confirmed swine influenza. See o If hospitals are not able to conduct initial rapid influenza testing, please contact the DOHMH to arrange for testing for influenza A. Management of patients with mild influenza-like illness o Patients with mild illness should be encouraged to stay home until hours after resolution of symptoms. Patients should be instructed to wash their hands frequently, cough into a tissue or sleeve (not into bare hands or onto another person), dispose of tissues in the trash, and stay home from school or work until hours after illness is resolved. o At this time, we are not recommending routine influenza testing and/or antiviral treatment for persons with mild influenza-like illness, unless they meet the usual criteria for empiric influenza treatment based on underlying illnesses that put them at higher risk for complications of any type of influenza. According to the CDC, vaccination for seasonal influenza is unlikely to be effective for prevention of swine influenza. Additional information on the outbreaks in the US and Meico, including NYC, as well as further clinical guidance will be provided as it becomes available. For updated information on the national situation, see Dear Colleagues, On April 23, a high school in Queens was noted to have an outbreak of mild febrile respiratory illness that was confirmed last night to be caused by influenza A. Specimens were sent to the NYC Public Health Laboratory and were untypeable for human H1 or H3 strains, meeting the CDC case definition for probable swine influenza. These specimens are being forwarded to CDC today for further testing to determine if these infections are due to swine influenza. Results should be available tomorrow. The high school has approimately 2,700 students, and as of yesterday, 200 children were reported to be ill, mostly with mild influenza-like symptoms (fever, cough, and/or sore throat). None of the cases were severe or required hospitalization. In the United States, there are currently 6 California residents and 2 Teas residents who have been diagnosed with swine influenza A (H1N1) virus infection; all of these patients had mild illness (only one hospitalization) and all have recovered. Isolates from California and Teas have been found to be susceptible to the neuraminidase inhibitors (oseltamivir and zanamavir) but resistant to the adamantanes (amantadine and rimantadine). In addition, there has been an outbreak of respiratory illness in Meico, which has been confirmed as at least partly due to swine influenza; clinical and epidemiologic details of this outbreak are still pending, but preliminary reports are of thousands of cases and approimately 70 deaths. Surveillance for Swine Influenza in Hospitalized Cases Citywide: The NYC Health Department is now prioritizing its surveillance efforts for swine influenza on identifying potential cases of febrile, respiratory illness in hospitalized patients, in order to rapidly identify and confirm potential cases with more severe illness. Therefore, DOHMH requests that providers seeing patients with acute febrile respiratory illness only test those patients who are either currently hospitalized or are being admitted to the hospital with uneplained febrile respiratory illness. These patients should be tested for influenza using either a commercial rapid test, or direct or indirect immunofluorescence. Patients who test positive for influenza A should be reported to DOHMH and have specimens referred to DOHMH for further testing to determine whether the influenza A can be subtyped. See contact information below. DOHMH will arrange for transportation of clinical specimens to the Public Health Laboratory. See attached instructions for 2

3 collecting and submitting laboratory diagnostic specimens for swine influenza testing. Nasopharyngeal swabs are the preferred specimens for influenza testing in the current swine influenza contet. Management of Persons with Milder Influenza-like Illness At this time, providers assessing patients with mild febrile respiratory illness in clinical settings, including emergency departments, should not test for influenza and should not administer antiviral medications for presumptive therapy, unless patients meet the usual criteria for empiric influenza treatment based on underlying illnesses (listed below) that put them at higher risk for complications of any type of influenza. These patients may be sent home with instructions to stay at home until hours after their symptoms resolve and instructed on the importance of hand and respiratory hygiene. Instructions should be given to seek medical care with worsening of symptoms. Infection Control For current recommendations on infection control in medical care facilities, see Antiviral Treatment and Prophylais Guidelines Swine influenza viruses identified in this outbreak to date have been susceptible to both oseltamivir and zanamivir. Antiviral therapy with one of these agents should be initiated empirically for patients currently hospitalized with severe uneplained febrile respiratory illness, pending testing for swine influenza. See for specific guidelines. This document also includes detailed guidance on antiviral prophylais. The Health Department requests that providers also immediately report any clusters of influenza-like illness in medical facilities, congregate settings such as long-term care facilities, or schools. To contact the Health Department, including to report suspected cases of swine influenza in hospitalized patients and arrange for specimen testing, please call the Provider Access Line at This number is also available for questions or consultations by providers. As always, we appreciate the cooperation of the medical community in New York City and will update you with further information when it becomes available. Sincerely, Scott A. Harper, MD, MPH, MSc Medical Epidemiologist Zoonotic, Influenza, & Vectorborne Diseases Unit Bureau of Communicable Disease Annie Fine Annie Fine, MD Medical Director Zoonotic, Influenza, & Vectorborne Diseases Unit Bureau of Communicable Disease 3

4 Definitions of Respiratory Illness 1. Acute respiratory illness Recent onset of at least two of the following: 1. rhinorrhea or nasal congestion 2. sore throat 3. cough 4. fever or feverishness 2. Influenza-like illness: fever >37.8 C (100 F) plus cough or sore throat Case Definitions for Infection with Swine Influenza A (H1N1) Virus 1. A Confirmed case of swine influenza A (H1N1) virus infection is defined as a person with an acute respiratory illness with laboratory confirmed swine influenza A (H1N1) virus infection at CDC by one or more of the following tests: 1. real-time RT-PCR 2. viral culture 3. four-fold rise in swine influenza A (H1N1) virus specific neutralizing antibodies 2. A Probable case of swine influenza A (H1N1) virus infection is defined as a person with an acute respiratory illness with an influenza test that is positive for influenza A, but H1 and H3 negative. 3. A Suspected case of swine influenza A (H1N1) virus infection is defined as: 1. A person with an acute respiratory illness who was a close contact to a confirmed case of swine influenza A (H1N1) virus infection while the case was ill OR 2. A person with an acute respiratory illness with a recent history of contact with an animal with confirmed or suspected swine influenza A (H1N1) virus infection OR 3. A person with an acute respiratory illness who has traveled to an area where there are confirmed cases of swine influenza A (H1N1) Conditions which increase the risk of severe influenza infection chronic pulmonary, cardiovascular, renal, hepatic, hematological, or metabolic disorders, immunosuppression, compromised respiratory function, including conditions which increase the risk for aspiration, long-term aspirin therapy pregnancy age > 65 years age < 2 years 4

5 Diagnostic Testing Using Nasopharyngeal Swabs INSTRUCTIONS ON NASOPHARYNGEAL SPECIMENS FROM HOSPITALIZED PATIENTS WITH SEVERE UNEXPLAINED FEBRILE RESPIRATORY ILLNESS These laboratory instructions provide guidance on what specimens to collect and how to arrange transportation. It is absolutely critical that specimens be collected properly, labeled properly, stored refrigerated and submitted with a completed PHL laboratory submission form. WHO: Hospitalized patients with severe uneplained febrile respiratory illness WHAT: Preferred specimen is 1-2 nasopharyngeal swabs in 2-3 ml viral transport medium* (VTM). Specimens should be collected within the first hours of onset of symptoms, and no later than 5 days after onset of symptoms. HOW: Use infection control precautions: o Personal protective equipment: fit-tested disposable N95 respirator [if unavailable, wear a medical (surgical mask)], disposable gloves, gown, and goggles. o When completed, place all PPE in a biohazard bag for appropriate disposal. o Wash hands thoroughly with soap and water or alcohol-based hand gel. How to do a nasopharyngeal swab o Use a fleible fine-shafted aluminum swab with a polyester (dacron or rayon, not cotton) tip. o Insert swab into the nostril and back to the nasopharyn and leave in place for a few seconds. o Slowly withdraw swab with a rotating motion. o Place tip of the swab into a vial containing 2 3 ml of virus transport medium* and cut the shaft. o Label the transport tube with the patient first and last name, DOB, type of specimen, and date and time of collection. o Complete the PHL virus isolation specimen submission form ( **Failure to complete or submit this form with the specimen could result in disposal of the specimen** o A second swab should be used for the second nostril. o Swabs of anterior nares and throat swabs are NOT acceptable for influenza testing.

6 (cont.) Diagnostic Testing Using Nasopharyngeal Swabs Storage o Place specimen(s) in a biohazard bag. o Keep specimen(s) refrigerated at 4ºC until pick-up. o If specimens cannot be processed within hrs, they should be kept frozen at or below 70 C. Transportation to the Public Health Laboratory o Insert the completed laboratory submission form. o Tips for completing the form: Under DOHMH Bureau, check BCD Under DOHMH Contact, put in the name of the contact person you spoke with Under Test(s) requested, check Influenza A and B Direct Antigen Detection, Influenza A real-time RT-PCR, Influenza A Subtyping (H1/H3) real-time RT-PCR (see below) Information on the form and the specimen has to match (name of pt, DOB, Specimen type, date and time of collection). o Contact (Provider Access Line) to make a request to the DOHMH for pick-up. * Virus transportation medium for use in collecting nasopharyngeal specimens Add 10 g veal infusion broth and 2 g bovine albumin fraction V to sterile distilled water (to 400 ml). Add 0.8 ml gentamicin sulfate solution (50 mg/ml) and 3.2 ml amphotericin B (250 µg/ml). Sterilize by filtration.