Public Health Agency of Canada
Symbol of the Government of Canada
Help the Government of Canada organize its website! Complete an anonymous 5-minute questionnaire. Start now.

Share this page

Joint Biosafety Advisory - Influenza A(H7N9) virus – March 17, 2014

This biosafety advisory is being provided by the Public Health Agency of Canada (PHAC) and the Canadian Food Inspection Agency (CFIA) to assist clinical/diagnostic and research laboratories in implementing proper biosafety procedures when handling samples containing influenza A(H7N9) virus that was recently identified in China. This advisory is based on currently available scientific evidence as of March 17, 2014 and is subject to review and change as new information becomes available. The Risk Group (RG) of influenza A(H7N9) virus is RG3.

1.0 Background

Influenza A(H7) viruses are a group of influenza viruses that normally circulate among birds. The influenza A(H7N9) virus seen in China is a reassortant virus containing genes from A(H7N9) and A(H9N2) and may be a potential pandemic agentFootnote 1,Footnote 2. It is genetically distinct from other A(H7N9) viruses previously identified in wild bird and poultry populations although clearly related to recent Eurasian lineage viruses.  This virus does not appear to cause severe illness in avian populations, and represents the first H7N9 subtype to cause infection in humans. Cases of human illness resulting from influenza A(H7) viruses have been documented; however, these illnesses were generally mild and symptoms ranged from conjunctivitis to mild respiratory illness, and no human-to-human transmission was observedFootnote 3,Footnote 4, moreover, these infections were associated with viruses that are highly pathogenic in poultry.

As of March 17, 2014, the influenza A(H7N9) virus recently identified in China has caused respiratory illness in 390 confirmed human casesExternal site, including 121 deaths.Footnote 5,Footnote 6,Footnote 7 All cases to date have presented with flu-like symptoms, which progressed to respiratory illness. Although the source, reservoir, route of infection, and mode of transmission of the virus are unknown, investigations are underway to determine these factors, and most infected individuals reported recent exposure to live poultry. There is no evidence of ongoing human-to-human transmission,Footnote 8 but the identification of four clusters of infection of two or more cases with close contact indicates limited human-to-human transmission may be possible. As of February 24, 2013, three travel-related cases had been reported outside of China, in Taiwan and Hong Kong.

This influenza A(H7N9) virus is currently considered a Foreign Animal Disease (FAD) agent as there may be consequences if this pathogen becomes prevalent in the poultry or wild bird populations in Canada.

2.0 Biosafety Requirements

The following table summarizes the appropriate physical and operational containment requirements for clinical/diagnostic and research laboratories handling or storing influenza A(H7N9) virus. Based on the clinical presentation of severe respiratory illness and death in humans, the potential for this virus to be a pandemic agent, and the fact that the virus is currently considered a foreign animal disease agent, this influenza A(H7N9) virus is classified as a Risk Group 3 (RG3) human pathogen, and a RG3 non-indigenous animal pathogen, requiring Containment Level 3 (CL3 or CL3-Ag) for all in vitro propagative or in vivo activities. Non-propagative clinical/diagnostic activities can be conducted at CL2 with additional biosafety requirements, as specified below. In the event of a non-negative human sample (positive for emerging respiratory pathogen), the sample is to be forwarded to the National Microbiology Laboratory (NML) for confirmatory testing. In the event that a veterinary diagnostic laboratory detects a non-negative sample, the work is to be stopped and the sample be transferred to the National Centre for Foreign Animal Disease (NCFAD) as per the policy in the Foreign Animal Disease Diagnostic Laboratory Containment StandardExternal siteFootnote 9.

The Agencies will continue to monitor this situation and will update this advisory based on new information, if appropriate. Laboratories should refer to the Canadian Biosafety Standards and Guidelines, 1st Edition 2013 (CBSG)Footnote 10 for a complete listing of the biosafety requirements.

Sample Type and Activity Minimum Containment Level Required
CL2 CL3

† With additional biosafety requirements as described in Section 3.0.
* Work in SA zones must meet the requirements in the CL3 column of the CBSG and work in LA zones must meet the requirements in the CL3-Ag column of the CBSG.

Non-Propagative Clinical/Diagnostic Activities
Examples of these activities include, but are not limited to :
  • processing specimens for packaging and distribution to laboratories;
  • diagnostic testing activities (excluding culture); and
  • molecular testing of nucleic acids.
 
Propagative and Non-propagative in vitro Activities Involving Known/Likely Positive Cultures
Examples of these activities include, but are not limited to :
  • culture of specimens
  • preparatory work for in vivo activities; and
  • processing positive cultures for packaging and distribution to laboratories

 

In vivo Work Activities

 

*

3.0 Additional Biosafety Requirements

Influenza A(H7N9) can be safely handled in a CL2, CL3 or CL3-Ag zone that meets the physical and operational requirements described in Part I Chapters 3 and 4 of the CBSG, as well as the additional requirements noted below.

3.1. Additional Operational Requirement for All Activities

  • All activities involving open vessels of infectious material to be conducted in a certified BSC or other appropriate primary containment device (CBSG R4.6.24);
  • Respirators to be worn (CBSG R4.4.8) where there is a risk of exposure to infectious aerosols that can be transmitted through the inhalation route or to aerosolized toxins, as determined by an LRA;
  • An additional layer of protective clothing to be donned prior to work with infectious material or infected animals, in accordance with entry procedures (CBSG R4.4.6). An additional layer of protective clothing (e.g., solid-front gowns with tight-fitting wrists, second pair of gloves, waterproof aprons or head covers) provides additional protection and guards against exposure following a tear that compromised, or a spill that contaminated, the outer protective layer;
  • Personnel to doff dedicated or additional layer of PPE when exiting the containment barrier (CBSG R4.5.13);
  • In the event of a non-negative human sample (positive for emerging respiratory pathogen), the sample is to be transferred to the National Microbiology Laboratory (NML) for confirmatory testing; and
  • In the event that a veterinary diagnostic laboratory detects a non-negative sample, the work is to be stopped and the sample be transferred to the National Centre for Foreign Animal Disease (NCFAD) as per the policy in the Foreign Animal Disease Diagnostic Laboratory Containment StandardExternal site.Footnote 9

3.2. Special Requirements for All Sample Types and Activities

  • Manipulations involving propagation/culture of the influenza A(H7N9) virus are not to be performed in the same laboratory space where the culturing material that may contain influenza virus is being performed simultaneously; and
  • Personnel are not to come in contact with susceptible animal species for a period of 5 days after handling samples containing influenza A(H7N9), as per standard foreign animal disease protocols.

4.0 Transportation

Packaging, shipping and transport of specimens must comply with the requirements of the Transportation of Dangerous Goods RegulationsFootnote 11, Transport Canada and the Dangerous Goods Regulations, International Air Transport Association.

  • For air shipments, cultures (i.e. propagated virus) should be shipped as Category A, UN2814.
  • For air shipments, patient/primary sample specimens should be shipped as Category B, UN3373.

For further information on how to receive training and certification in the Transportation of Dangerous Goods, please contact the Laboratory Safety Office at lsd-dsl@hc-sc.gc.ca or contact on the 24/7 emergency phone line at 613-292-6754.

5.0 Contact Information

Please note that this advisory is based on currently available scientific evidence and is subject to review and change as new information becomes available. Further biosafety information may be obtained from the:

6.0 References

Footnote 1
Butler, D. (2013). Novel bird flu kills two in China. Retrieved 04/02, 2013, from http://www.nature.com/news/novel-bird-flu-kills-two-in-china-1.12728
Footnote 2
European Centre for Disease Control and Prevention. (2013). Severe respiratory disease associated with a novel influenza A virus, A(H7N9) - China. Retrieved 04/03, 2013, from http://ecdc.europa.eu/en/publications/publications/ah7n9-china-rapid-risk-assessment.pdf
Footnote 3
Belser, J. A., Bridges, C. B., Katz, J. M., & Tumpey, T. M. (2009). Past, present, and possible future human infection with influenza virus A subtype H7. Emerging Infectious Diseases, 15(6), 859-865. doi:10.3201/eid1506.090072; 10.3201/eid1506.090072
Footnote 4
Heymann, D. L. (Ed.). (2008). Control of Communicable Diseases Manual (19th Edition ed.). Washington, DC: American Public Health Association.
Footnote 5
ProMED. (2013). Avian influenza, human (26): China H7N9 case list & map
Footnote 6
International Health Regulations (IHR) system. http://www.who.int/ihr/en/
Footnote 7
WHO Global Alert and Response. (2013). Human Infection with Influenza A(H7N9) in China Update. From http://www.who.int/csr/don/2014_03_17_h7n9/en/
Footnote 8
World Health Organization. (2013). Overview of the emergence and characteristics of avian influenza A(H7N9) virus. http://www.who.int/influenza/human_animal_interface/influenza_h7n9/WHO_H7N9_review_31May13.pdf
Footnote 9
Foreign Animal Disease Diagnostic Laboratory Containment Standard, 2007, Canadian Food Inspection Agencyhttp://www.inspection.gc.ca/english/sci/bio/anima/diag/diage.shtml
Footnote 10
Government of Canada (2013). Canadian Biosafety Standards and Guidelines (1st ed). Ottawa, ON, Canada: Government of Canada http://canadianbiosafetystandards.collaborations.gc.ca
Footnote 11
Transportation of Dangerous Goods Regulations, Transport Canada, http://www.tc.gc.ca/tdg/menu.htm