1 2009 Update from NYC Dept of Health on Swine
2009 New York City Department of Health and Mental
Health Alert #15: H1N1 (Swine Origin) Update
May 1, 2009
PLEASE NOTE: This is a rapidly evolving situation. This alert
provides interim guidance. Evidence of community transmission
of H1N1 (Swine Origin) (SO) is emerging but has not yet been
proven. This update provides:
• An epidemiologic update on the H1N1 (SO) outbreak in New York
• Change in the New York City case definition for H1N1 (SO)
• Updated infection control guidance (attached)
• Updated recommendations for home isolation of patients with
influenza-like illness (attached)
Refer to Health Alert # 13 for current reporting requirements,
laboratory diagnostic testing guidance, antiviral treatment and
prophylaxis recommendations. All guidance is likely to change
as the situation evolves and will be forwarded when available.
Please check the New York City Department of Health and Mental
Hygiene website at www.nyc.gov/health for
updated guidance (see Information for Providers).
New Developments since Health Alert # 14
New York City H1N1 (SO) Outbreak Update
Diagnostic testing at the Centers for Disease Control and
Prevention (CDC) has confirmed 49 cases of Swine-Origin
Influenza A (H1N1) (H1N1 [SO]) in New York City. Thirty-three
probable cases have also been identified. A cluster of
influenza-like illness at Public School Q177 and St. Francis
Preparatory School are epidemiologically related; the two
schools are in close proximity to one another in Queens. Both
schools have been closed. All confirmed cases can be
epidemiologically linked either to exposure to an ill person
associated with the two schools or to travel to Mexico.
However, DOHMH has now identified two probable cases without
apparent epidemiologic links: a 14-year-old Queens resident,
and a 20-year-old visitor to New York City. These findings,
along with other suggestive surveillance data presented below,
suggest that community transmission of H1N1 (SO) is now
occurring in New York City. The guidance provided here reflects
that new understanding.
To date, illness in New York City and the United States as a
whole continues to be similar to seasonal influenza, with the
overwhelming majority of diagnosed patients having had mild
illness. No deaths attributable to H1N1 (SO) have occurred in
New York City. DOHMH is actively conducting surveillance for
cases of severe, febrile respiratory illness due to H1N1 (SO)
in order to determine its frequency, risk factors for
developing more severe illness, clinical features and spectrum
of illness. Only one confirmed and 4 probable cases have been
hospitalized; none have had critical illness (e.g., none have
required ventilatory support) and all are recovering.
As part of its effort to understand the transmission and basic
epidemiology of H1N1 (SO) at the St. Francis Preparatory
School, the Health Department created an online questionnaire
to survey students, parents and staff at the school. The age
ncy reported the findings in an MMWR Dispatch (see http://www.cdc.gov/mmwr/preview/mmwrhtml/mm58d0430a1.htm
Of the 1,996 St. Francis Preparatory students who responded to
the survey, 659 (33%) reported being sick with flu-like
symptoms at some time since April 8. Most (82%) became ill
between Wednesday and Saturday (April 22-25), and 254 became
ill on April 23. Only 1% (27) reported being both sick and
feeling worse than the day before. Six of the ill persons
reported traveling to Mexico the week before, 1 traveled to
California and none went to Texas. Approximately 29% reported
that at least one other household member was sick, and a total
of 462 household members were reported by students to have been
sick at the time of the survey (see
Several individual cases and at least one cluster of influenza
in New York City, including both a case of influenza in a
student from Pace University and a cluster of influenza at
Manhattan’s Ascension School that were announced publicly, have
now been diagnosed as Influenza A (H3N2). These findings
provide evidence that seasonal influenza activity is ongoing in
New York City. It is not known what proportion of
influenza-like illness in the community is due to H1N1 (SO)
versus H3N2 or other respiratory pathogens. Because both H1N1
(SO) and influenza A (H3N2) are susceptible to oseltamivir and
zanamavir, empiric antiviral treatment and prophylaxis
recommendations have not been changed.
Syndromic surveillance data from hospital emergency room chief
complaints suggest that an increasing number of individuals are
being seen in emergency departments for influenza-like illness
(ILI). The largest increase has been seen in patients
complaining of fever in the 18-44 year old age group. It is not
known whether this increase reflects changes in care-seeking
behavior or a true increase in community ILI.
No increase in mort ality due to pneumonia or influenza has
Three adverse events due to oseltamivir use have been reported
to the NYC Poison Control Center. Two were dosage errors in
children resulting in vomiting. The third was a rash attributed
to an allergic reaction. As a reminder, dosage recommendations
for antiviral medications are available at
Given the evolving epidemiology of H1N1 (SO) influenza in NYC
and elsewhere, the number of NYC cases is expected to continue
to increase in the coming days. We will continue to update case
numbers and guidance in subsequent alerts.
US and Global H1N1 (SO) Epidemiologic Update
As of 05/1/09, 141 cases have been confirmed in 19 states
across the US. There has been one death in a 23-month-old child
in Texas with an underlying high risk medical condition. 331
confirmed cases of H1N1 (SO) have been reported from 11
countries, as of today. The World Health Organization (WHO)
pandemic influenza alert level is 5, indicating that widespread
human infection is occurring and a pandemic is imminent. (The
WHO uses a 6 point scale to assess the pandemic threat
New Guidance and Recommendations
Revised New York City Case Definition for H1N1 (SO)
The New York City case definition for H1N1 (SO) has been
revised. The new definition follows:
A confirmed case of H1N1 (SO) infection is defined as a person
with an acute febrile respiratory illness with laboratory
confirmed H1N1 (SO) infection at CDC by one or more of the
• real-time RT-PCR, or
• viral culture
A probable case of H1N1 (SO) infection is defined as a person
with an acute febrile respiratory illness who is positive for
influenza A, but negative for H1 and H3 by influenza RT-PCR
A suspected case of H1N1 (SO) infection is defined as a person
with unexplained acute febrile respiratory ill ness.
(Patients with an acute febrile respiratory illness who have a
negative PCR test for influenza A can be considered non-cases
of H1N1 [SO]).
New Infection Control Recommendations
See “Infection Control Guidelines for Medical Facilities”,
Epidemiologic risk factors should no longer be used in triage
and screening or in determining infection control measures and
precautions to be taken.
• Hospitals and outpatient clinics should institute screening
and isolation protocols for patients presenting with acute
febrile respiratory illness.
o Signage should be placed at all entryways to the facility
advising patients to identify themselves if they have acute
febrile respiratory illness, use masks or tissues if
coughing/sneezing, and perform hand hygiene. Sample posters
developed by DOHMH are attached and may be reproduced for
o While awaiting medical examination, symptomatic patients
should be quickly separated from oth er patients in the waiting
areas either by placement in a single separate room or at least
3-6 feet away from others.
• For ALL patients being treated for acute febrile respiratory
illness, medical facilities should implement standard and
contact precautions with eye protection. Healthcare personnel
who will perform direct patient care or collect specimens from
the ill patient should wear gowns, gloves, disposable
fit-tested N95 respirator, and eye protection.
• While in the hospital, isolation precautions should be
continued for seven (7) days from symptom onset or until the
resolution of symptoms, whichever is longer.
• Disposal of personal protective equipment should be based on
the hospital’s infection control policies.
• Aerosol generating procedures (nebulizer treatments,
suctioning, intubation, nasopharyngeal swab or sputum
collection, and bronchoscopy) should be performed in an
airborne infection isolation room (AIIR). If an AIIR is not
avail able, use clinical judgment to decide whether the
procedure can be performed in a private room with the door
closed. Medical providers should wear an N95 respirator and eye
protection. Higher respiratory protection is not needed.
DOHMH reminds providers to provide pneumococcal vaccination to
their patients as indicated, particularly since superinfection
with Streptococcus pneumoniae has been shown to cause
additional morbidity and mortality in patients with
Updated Home Management of Patients Being Discharged with
Suspected, Probable or Confirmed H1N1 (SO)
DOHMH has posted guidance on home isolation at
This document may be reproduced and offered to patients being
discharged from medical facilities. Translated materials should
be available shortly on our website.
Persons with fever and cough should be advised to stay home
until 24 hours after complete resolution of symptoms. Please
note that this is a change from previous guidance.
• Patients should be encouraged to CALL prior to coming in for
medical care. Those with mild illness should be encouraged to
stay home. They should not attend work or school until 24 hours
after complete resolution of symptoms.
• Patients should be advised that the great majority of cases
of H1N1 (SO) have been mild and do not require antiviral
treatment or laboratory diagnosis. They should be advised NOT
to take antiviral medication unless prescribed by a
• Patients should be educated regarding signs of worsening
illness and advised to call if these occur, or seek care at an
• Patients should cover their mouth and nose with a tissue or
handkerchief when coughing or sneezing, and should wash their
hands with soap and water frequently.
• Outpatient providers are asked not to refer patients to the
hospital emergency room unless the patient is severely ill.
Emergency rooms have experienced increased volume, with many
visits by persons with mild ILI or “worried well.”
• We continue to recommend that home care for persons with mild
ILI be given by one primary caregiver if possible, and that the
patient should be separated to the extent possible from other
members of the household, preferably in a separate bedroom. The
caregiver should wear a mask, either surgical or N95, when
close contact with the ill person is unavoidable. The ill
person should also wear a surgical mask when close contact with
other individuals in the home is unavoidable.
• Asymptomatic household or other close contacts of persons
with respiratory illness are not being advised to stay home or
to take any special precautions when outside the home. However,
if they become ill with acute respiratory illness, they should
also stay in home isolation until 24 hours after symptoms
At this time we are not recommending that well persons in NYC
restrict their public activities or movements regardless of
underlying conditions that may put them at risk for
complications due to influenza.
Surveillance and Reporting
• We continue to ask NYC providers to report hospitalized
patients with severe, unexplained febrile, respiratory illness
to the Provider Access Line at 1-866-NYC-DOH1 (1-866-692-3641).
Providers should continue to test only patients with severe
febrile respiratory illness for influenza A, using a
commercially available rapid test, PCR or immunofluorescence
test (e.g., DFA or IFA).
• Providers are also asked to continue to report clusters of 3
or more cases of acute febrile respiratory illness in schools,
day cares, congregate living facilities such as prisons or
homeless shelters, and medical or long term care
• In order to ensure that sufficient laboratory resources are
avai lable, testing at the Public Health Laboratory will only
be approved for severe cases or clusters of acute febrile
respiratory illness that are first reported to DOHMH via the
Provider Access Line. DOHMH staff will evaluate the case and
advise whether testing for H1N1 (SO) at the Public Health
Laboratory is indicated. DOHMH will facilitate specimen
transport and testing for cases when testing is indicated. If
approved, please send only one specimen per patient.
• At this time, adverse events or poisonings due to antiviral
medication should be reported to the NYC Poison Control Center
at 1-212-POISONS (212-764-7667) or 1-800-222-1222.
Diagnostic Testing and antiviral treatment recommendations are
unchanged. See Health Alert # 13 for guidance.
Antiviral prophylaxis recommendations are currently under
Antiviral prophylaxis should ONLY be considered for exposures
to persons with probable or confirmed H1N1 (SO) or acute
febrile respiratory illn ess AND one of the following
epidemiologic risk factors in the 7 days prior to illness
• Travel to Mexico
• Close contact with an ill person associated with St. Francis
Preparatory High School or Public School Q177
• Close contact with a probable or confirmed case
The DOHMH interim recommendation is to consider offering
prophylaxis to persons with underlying conditions that increase
the risk of complications due to influenza when exposed to a
person who meets one of the above criteria. For the present
time, given limitations on antiviral supplies, the limited
availability of laboratory testing to distinguish H1N1 (SO)
from other respiratory pathogens (including seasonal influenza,
which is still circulating) clinical judgment should be used to
decide whether healthcare workers should take prophylactic
antiviral medications after unprotected direct exposures to
patients with acute febrile respiratory illness.
The CDC is updating guidanc e on various issues relating to the
H1N1 (SO) outbreak on its website daily. Please see www.cdc.gov/swineflu
for updated national recommendations.
To contact the Health Department, including to report suspected
cases of H1N1 (SO) in hospitalized patients and arrange for
specimen testing, please call the Provider Access Line at
866-NYC-DOH1. 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.
The Swine Influenza Investigation Team
New York City Department of Health and Mental Hygiene