IK
1500 Forest Glen Road
Silver Spring, MD
20910-1484
Phone: (301)754-7000
www.holycrossheatth.org
HOLY CROSS HOSPITAL
Memo
TO:
All Holy Cross Hospital Affiliated Physicians
All Holy Cross Hospital Nursing Staff
FROM:
Sheryl Stuckey, MT (ASCPP^V^
Manager, Microbiology Laboratory
THRU:
Pablo Gutman, MD
Medical Director, Microbiology Laboratory
DATE:
October 26, 2012
SUBJECT:
2012 influenza virus Testing Guidelines
During July and August a novel strain of the influenza virus H3N2v was detected in several
states, infections with this virus were found to be related to swine exposure. As a result the
Maryland Department of Health and Mental Hygiene Laboratory Administration will conduct
enhanced surveillance (culture and/or PCR tests) for the influenza A virus during this seasonal
period.
H3N2v virus infection cannot be distinguished by clinical features from seasonal influenza A
or B infection. It is very important that you document any recent swine exposure in
the week prior to the onset of illness.
The laboratory will transition the collection method to one using a universal viral transport
media. This is being done to facilitate the timeliness of further testing at the state laboratory
when required. Our laboratory currently provides a rapid enzyme immunoassay (&A)
test for the detection of influenza A and B from nasopharyngeal specimens.
The following is the test algorithm that will be used for enhanced surveillance of
patients with influenza-like illness (ILI):
Patient Type
Hospitalized
Outpatient
Outpatient
Patient
History
With or
without
Swine
Exposure
Recent
Swine
Exposure
No Recent
Swine
Exposure
Rapid Test
Result
Forwarded to the State
Laboratory for Testing
Any Test
Result
Yes
Any Test
Result
Yes
influenza A
Positive only
Yes
Holy C r o s s . E x p e r t s in M e d i c i n e , S p e c i a l i s t s in C a r i n g .
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1500 Forest Glen Road
Silver Spring, MD
20910-1484
HC.
Phone: (301)754-7000
www.holycrosshealth.org
HOLY CROSS HOSPITAL
Patient Type
Adult
Outpatient
Pediatric
Outpatient
(< 18 years
of age)
Patient
History
Rapid Test
Result
No Recent
Swine
Exposure
influenza A
Negative
or
Any influenza
B Result
(positive or
negative)
NO Recent
Swine
Exposure
influenza A
Negative
or
Any Influenza
B Result
(positive or
negative)
Forwarded to the State
Laboratory for Testing
NO
RAPID A AND B NEGATIVE RESULTS =
UNABLE TO RULE OUT INFLUENZA
INFECTION
Please correlate test results with
patient history, clinical signs and
symptoms and other relevant data
Yes
Critical Ordering and Testing Notes:
1. Nasopharyngeal swabs, aspirates or washings are required for testing.
2. Rapid enzyme immunoassay (ElA) tests may detect the presence of influenza A or B, but
cannot distinguish specific strains of the influenza virus.
3. The overall sensitivity of ElA tests is low and may vary depending on prevalence of
influenza and the strains of the virus in circulation in the community.
4. False positive rapid ElA test results may occur when there is a low prevalence of the
influenza virus in the community.
5. Order the influenza A/B Antigen test in Powerchart.
6. Document recent swine exposure and include in the test order comment.
Thank you for allowing us to help you serve your patients. Please contact the laboratory
director, Jay Marchwinski (301-754-7321), or myself if you have any questions or concerns
regarding our laboratory's practices or service to your patients.
References:
1. Guidance for Physicians on the use of Rapid influenza Diagnostic Tests, Seasonal influenza
(Flu) website, Centers for Disease Control and Prevention,
http://www.cdc.gov/flu/professionals/diagnosis/clinician guidance ridt.htm#Figure3,
December 7, 2011.
2. Collection of Nasopharyngeal Swabs,
http://www.voutube.com/watch7v = 21 nAf zgTdRl&feature = related.
cc:
S. Mitchell, MD
B. Eig, MD
J. Marchwinski
M. Mohyla, RN, CIC
Holy C r o s s . E x p e r t s in M e d i c i n e , S p e c i a l i s t s in C a r i n g .
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