Laboratory
SWINE INFLUENZA

Agent Overview:		Swine Influenza A H1N1: Causative agent is an influenza virus predominantly 
			found in pig populations. People do not normally get Swine Influenza A 
			(H1N1), but this strain has acquired the ability to transmit from pigs to humans, 
			and humans to humans. An outbreak of human cases of Swine Influenza A 
			(H1N1) infection is occurring internationally. While the disease has resulted in 
			deaths, most cases appear to be mild. 

			Since humans are unlikely to have inherent immunity, there is the potential 
			that this outbreak can become a pandemic. There is no current vaccine. The 
			virus is susceptible to antiviral drugs.
		
Lab Specimen Submittal:	Delaware Laboratories should send all rapid influenza A+ specimens as 
			soon as possible to the Delaware Public Health Laboratory (DPHL) for 
			subtyping.  Although Swine flu is subtype H1, it does not subtype using 
			the current FDA approved PCR method.  Any specimens that DPHL is 
			unable to subtype as H1 or H3 will be sent to CDC’s Influenza Division 
			for further diagnostic testing. 
		
			Clinicians should consider submitting specimens from patients presenting with 
			febrile respiratory illness who:
			*	Live in an area where human cases of swine influenza A (H1N1) has been 
				identified, OR 
			*	Have traveled to an area where human cases of swine influenza A (H1N1) 
				has been identified, OR 
			*	Have been in contact with ill persons from these areas in the 7 days prior 
				to their illness onset. 

			Case Definition for Infection with Swine Influenza A (H1N1) Virus: A confirmed 
			case is defined as a person with an acute respiratory illness confirmed as 
			swine influenza A (H1N1) virus infection by CDC laboratory testing using 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.

			Probable Case Definition of Swine Influenza A (H1N1) virus:  A person with an 
			acute respiratory illness with an influenza test that is positive for influenza A, 
			but H1 and H3 negative.

			Suspected Case Definition of Swine Influenza A (H1N1) virus:
			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) within 7 
				days of suspect case’s illness onset.

Type of Specimens 
Necessary for Testing:	Clinical specimens for testing:  If Swine Flu is suspected, clinicians should
			obtain a respiratory swab for Swine Influenza testing and place it in a 	
			refrigerator. Use two dry Dacron swabs (not cotton) to collect specimen and 
			put in a sterile tube.

			SPECIMEN COLLECTION from ill patients: Upper Respiratory: 
			nasopharyngeal aspirate and oralpharyngeal swabs. Lower Respiratory: 
			Bronchoalveolar lavage (BAL), tracheal aspirate or pleural tap.

			To diagnose Swine Influenza A infection, a respiratory specimen	would 
			generally need to be collected within the first 4 to 5 days of illness (when an 
			infected person is most likely to be shedding virus). However, some persons, 
			especially children, may shed virus for 10 days or longer. At this time, 
			identification as a Swine Flu Influenza A virus requires sending the specimen 
			to CDC for laboratory confirmatory testing.

			When influenza is detected in your laboratory by RAPID TESTING methods, 
			please send an aliquot (1-2 ml) of the original suspension (not exposed to test 
			kit reagents) in viral transport media or sterile diluent; or if an additional 
			original specimen is available, that is preferable. 

			When influenza is detected in your laboratory by VIRAL CULTURE, please 
			send the actively growing viral culture tube with 2 ml of viral maintenance 
			media. 

Packaging Instructions: 	Pack collected clinical specimens in a sterile tube and place them in a 
			refrigerator (not a freezer). Once collected, the clinician should contact the 
			Delaware Public Health Laboratory at (302) 223-1520 to facilitate transport 
			and timely diagnosis. Transported specimens should be in a cooler and in 
			unbreakable double containers. Avoid manipulation of specimen. 

Receiving Specimens: 	DPHL couriers pick up specimens daily at designated locations throughout the 
			state. Specimens are also accepted at the back of the building by the loading 
			dock. Submitters must have the proper submission form completed.
 	
Reporting Results: 	A positive or negative test result is issued upon completion of PCR. PCR may 
			take 4 to 24 hrs. However, all A positive nonsubtypeable PCR results must be 
			confirmed by CDC.
	
Contact Information:	Jane Getchell, DrPH, DPHL director, or Christina Pleasanton, Deputy Director 
			302-223-1520 (24/7 coverage). 

Website:			For locations of courier pick-up sites, specimen submission forms, and other 
			information see the DPHL website at 					
			http://www.dhss.delaware.gov/dhss/dph/lab/labs.html.
 


24/7 Emergency Contact Number:  1-888-295-5156
Revised: 04/2009  Doc. #35-05-20/09/04/14