Clinical Virology Laboratory -
Guidelines for the Choice and Handling of Specimens

Specimens for virus detection should be collected as follows:
  • Throat wash
    The patient gargles with 10 mL of sterile balanced salt solution (Hank's or Earles BSS) or trypticase soy broth (TSB); expelled into a sterile container.

  • Urine
    Random clean-catch sample collected in a sterile container.

  • Blood  
    Collect 7-10 mL of blood in a Yellow ACD tube (Solution A or B). Blood more than 72 hrs old from time of collection to the time of processing (9AM) will be rejected. See additional policy guidelines.

  • NP Swab  
    Insert a flexible fine-shafted swab through the nostril into the nasopharynx and rotate swab gently a few times. Place into M4 viral transport media.

  • Vesicle fluids  
    Withdraw vesicle fluid using a tuberculin syringe or swab the vesicle and place it in an M4 Culture Transport Tube or 1 ml of BSS or TSB; crusted, dry lesions are not vesicles and are not appropriate for virus isolation.

  • Tissue  
    Collect aseptically and keep moist by placing in sterile container with 2 mL of BSS, TSB, saline or viral transport media M4.

  • Stool  
    Approximately 5 gm of stool placed in a tightly-capped sterile container without preservatives. A swab covered with stool is acceptable for culture but not preferred. Swabs are UNACCEPTABLE for Clostridium difficile toxin.
All specimens EXCEPT BLOOD (SEE PROCEDURE BELOW) should be tightly sealed, kept cold, and sent on wet ice or a "cool pack" (NOT FROZEN) to the laboratory as soon as possible, preferably on the day of collection.

Specimens for cytomegalovirus (CMV) isolation should be sent as soon as possible to our laboratory since this virus is very heat labile and the probability of isolating it decreases rapidly with time.

If absolutely necessary, all specimens EXCEPT BLOOD and those for CMV, RSV and VZ can be frozen at -50°C or below (do not use -20°C) and sent to the laboratory on dry ice.

Note: Specimens received after 2 PM may not be processed until the next day.