COVID-19: FAQ for health professionals working with blood products

NOTE: This information reflects evidence available at the time of publication.

1.  Are health professionals at risk of SARS-CoV-2 infection when handling blood products from Canadian Blood Services?

Last updated:  June 19, 2020

Health-care workers who handle fresh blood components from Canadian Blood Services (i.e., red blood cells, platelets, plasma) may have questions about whether accidental exposure to these products puts them at risk for COVID-19. The following evidence supports the view that the SARS-CoV-2 virus is not transmitted by handling blood. In addition, evidence supports the view that the SARS-CoV-2 virus is not transmitted through blood transfusion.1  

There are no examples of respiratory viruses being transmitted through blood.
To date, there have been no cases of respiratory viruses, including SARS-CoV-2, being transmitted through blood. Although the transmission routes of SARS-CoV-2 have not been well characterized, they are thought to be similar to the major routes of transmission identified for two other coronavirus infections that cause severe respiratory syndrome: Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS). SARS-CoV-2, like other respiratory viruses, is thought to be transmitted through respiratory droplets, person-to-person contact and fomites (inanimate objects like surfaces or items contaminated with infectious droplets).

Blood cells are unlikely targets for the SARS-CoV-2 virus.
SARS-CoV-2 infection of blood cells is not likely based on what we know about how the virus enters cells. The SARS-CoV-2 virus binds to a cell-surface receptor called angiotensin-converting enzyme 2 (ACE2) before it can infect a cell. ACE2 receptors are primarily found in the airways—on cells of tissue lining the nose and on alveolar cells in the lungs—but they are also found in other parts of the body. Based on this route of entry, the cells found in blood are unlikely targets for the SARS-CoV-2 virus: ACE2 receptors have not been detected in red blood cells and are absent or present in very limited amounts in immunocytes and lymphatic cells.2 While there is a theoretical possibility that SARS-CoV-2 can infect blood cells, the evidence does not support this view.

There is no evidence that the SARS-CoV-2 virus is viable in blood of COVID-19 patients or can be transmitted from asymptomatic blood donors.
Viral RNA from the SARS-CoV-2 virus has been detected in plasma or serum from a small number of symptomatic3-6 and asymptomatic6, 7 COVID-19 patients. Detection of viral RNA in a biological sample does not necessarily mean that infectious virus is present, but it could indicate presence of viral RNA fragments. To date, there is no evidence that the virus is viable or replicating in blood. One study attempted to isolate live virus from clinical samples of nine hospitalized COVID-19 patients; infectious virus could not be isolated from blood samples but was readily isolated from throat and lung swab samples.8

Limited evidence suggests asymptomatic blood donors do not transmit SARS-CoV-2 to recipients. A study from Korea reports seven blood donors were identified as COVID-19 confirmed cases after donation.9 However, stored samples from the COVID-19 cases all tested negative for SARS-CoV-2 RNA and three recipients who had been transfused with blood components from the COVID-19 confirmed donors all tested negative for SARS-CoV-2. The view that SARS-CoV-2 is not transfusion transmitted is also supported by a case report of a Korean man who received an apheresis platelet transfusion from an individual who was subsequently diagnosed with COVID-19.10 The recipient tested negative for SARS-CoV-2  in four subsequent tests.

References

1.    Katz LM. Is SARS-CoV-2 transfusion transmitted? Transfusion. 2020;60(6):1111-4.
2.    Harmer D, Gilbert M, Borman R, et al. Quantitative mRNA expression profiling of ACE 2, a novel homologue of angiotensin converting enzyme. FEBS letters. 2002;532(1-2):107-10.
3.    Chan JF, Yuan S, Kok KH, et al. A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster. Lancet (London, England). 2020;395(10223):514-23.
4.    Huang C, Wang Y, Li X, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet (London, England). 2020;2020(395):497–506.
5.    Wang W, Xu Y, Gao R, et al. Detection of SARS-CoV-2 in Different Types of Clinical Specimens. JAMA. 2020;10.1001/jama.2020.3786.
6.    Corman VM, Rabenau HF, Adams O, et al. SARS-CoV-2 asymptomatic and symptomatic patients and risk for transfusion transmission. Transfusion. 2020;10.1111/trf.15841.
7.    Chang L, Zhao L, Gong H, et al. Severe Acute Respiratory Syndrome Coronavirus 2 RNA Detected in Blood Donations. Emerg Infect Dis. 2020;26(7).
8.    Wolfel R, Corman VM, Guggemos W, et al. Virological assessment of hospitalized patients with COVID-2019. Nature. 2020;10.1038/s41586-020-2196-x.
9.    Kwon SY, Kim EJ, Jung YS, et al. Post-donation COVID-19 identification in blood donors. Vox sanguinis. 2020;10.1111/vox.12925.
10.   Cho HJ, Koo JW, Roh SK, et al. COVID-19 transmission and blood transfusion: A case report. Journal of infection and public health. 2020;10.1016/j.jiph.2020.05.001:10.1016/j.jiph.2020.05.001.

2.  Does Canadian Blood Services test potential blood donors for COVID-19?

Last updated: May 29, 2020

Canadian Blood Services does not test donors for COVID-19. However, it constantly reviews donor eligibility criteria to ensure only healthy people can donate blood. Visit Canadian Blood Services’ COVID-19 Q& A on blood and plasma donations for more information about blood and plasma donation.

3. Does Canadian Blood Services test for SARS-CoV-2 in donated blood?

Last updated: May 29, 2020

No, Canadian Blood Services does not currently test for SARS-CoV-2 in donated blood. Current evidence suggests the virus is not transmissible through transfusion of blood and blood products. 

4. Can shipping containers and blood bags received from Canadian Blood Services be cleaned?

Last updated: May 29, 2020

Yes, shipping containers, blood bags, and labels can all be cleaned. Local policies for cleaning products must be developed according to manufacturer recommendations detailed in Customer Letter #2020 – 17: Exterior Cleansing of Shipping Containers and Blood Bags, which includes information on appropriate disinfectants and how to use them. Note that disinfectants were not tested for effectiveness in eliminating the SARS-CoV-2 virus but were confirmed to be safe for the materials and contents.

  • Shipping containers:  The shipping containers currently in use by Canadian Blood Services may be wiped with disinfectant. Disinfectants should be applied to the wipe and not directly to the container’s surface.
  • Blood bags:  The bags used for blood components (red blood cells, pooled platelets, apheresis platelets, plasma) can be wiped down without harming the plastic or the bag’s contents. The manufacturer’s recommended cleaning solution(s) differ for each type of blood component.
  • End Labels:  Washing/wiping labels with a variety of disinfectants is not harmful to the label or legibility of the print.

5. Is there guidance on infection prevention and control when blood components and products are returned to inventory?

Last updated: May 29, 2020

Yes, see the best practices and considerations developed by the National Advisory Committee on Blood and Blood Products in this document: Infection and Prevention Control Considerations for Return of Blood Components and Products to Inventory, along with Appendix A, which provides information about SARS-CoV-2 persistence on different materials.