|
| |
Virology
           
Special collection materials and transport
media are available in Room 5.175 McCullough Building. When the laboratory is closed, they
may be obtained from Microbiology Specimen Receiving, Room 5.137 McCullough.
Specimens must be collected as soon as
possible after the onset of illness. Culture specimens should be immediately transported
to the laboratory on ice to insure virus viability. Specify suspected viral agents on
request slip.
Direct Viral Antigen Detection
1. Rapid Direct Viral
Antigen Detection for Respiratory Specimens
Viral culture can detect most of the viral
agents associated with respiratory disease but may require several days to a week to
become positive. Direct detection of viral agents using rapid test methods, i.e.
immunofluorescent stains or enzyme-linked assays, can dramatically speed detection of
specific viral agents.
The most critical factor in the direct
detection of respiratory viruses is collection of a proper specimen containing adequate
numbers of infected cells. The specimen of choice is a nasal wash.
Aspirate the PBS into the bulb. Tilt the
tube. Use all the PBS. For young infants, use 3-5 mL. Empty the tube of excess PBS to
avoid diluting the specimen.
Hold the patient's face chin up. A sitting
position will work best. Fit the tip of the bulb into a nostril.
Quickly squeeze the bulb. Immediately
aspirate the PBS back into the bulb.
Transfer the specimen back to the empty
PBS tube. Label the tube.
Transport the specimen on ice. Place the
specimen in the ice bucket.
Return the rubber bulb to the holding area
or laboratory along with the specimen.
Select a fresh vesicle (<3 days old).
Scabs, vesicular fluid, bloody specimens, or pus are unsatisfactory for FA examination.
Incise the vesicle peripherally with the
beveled edge of a sterile needle and gently lift back the top of the vesicle.
Blot the excess fluid with a sterile
culturette swab and submit for virus isolation in viral transport medium (M4).
Roughly scrape the base of the lesion with
the scalpel blade to obtain epithelial cells. Do not induce bleeding. It is important
to obtain a sufficient quantity of basal epithelial cells.
Thinly spread the collected material over
the 2 wells and label the slide with patient's name. Allow to air dry.
Place the slide in slide holder provided
and label with the patient's name and UT number.
Transport to the laboratory along with the
specimen for culture. A culture backup is required for HSV.
Table of infections and common virus/agent
involved with suggested specimens.
|
Infection and Common
Virus/Agent Involved |
Suggested Specimens |
|
Arthralgias/Myalgias |
|
Arboviruses
|
Routine culture not available;
serologies suggested. |
Coxsackie A and B
|
Throat swab, stool/rectal swab |
EBV
|
Routine culture not available;
serologies suggested. |
Rubella
|
NP swab, urine |
|
Central Nervous System |
|
Arboviruses
|
Routine culture not available;
serologies suggested. |
Enteroviruses
|
Throat, stool/rectal swab, CSF |
Herpes simplex (HSV)
|
CSF, vesicle fluid, brain tissue
(temporal lobe) |
Influenza
|
Nasal secretion/washing, throat |
LCM
|
Routine culture not available;
serologies suggested. |
Mumps
|
Throat, CSF, urine |
|
Congenital infection |
|
CMV
|
Urine, blood (4 mL/7 mL), throat |
Herpes simplex
|
Vesicle fluid, throat, eye, CSF |
Rubella
|
NP swab, urine, throat |
CMV
|
Blood-buffy coat (7 mL/EDTA
purple-topped tube), urine, bronchoalveolar lavage (BAL), lung, throat, sputum, trach
suction, bronch brush/wash |
|
Exanthems-Maculopapular |
|
Enteroviruses
|
Throat, stool/rectal swab |
Measles
|
Throat, NP swab, blood (7 mL
green-topped tube) |
Rubella
|
NP swab, throat |
|
Exanthems-Vesicular |
|
Coxsackie A
|
Throat, stool/rectal swab, vesicle
fluid |
Herpes simplex (HSV)
|
Vesicle fluid/swab |
Varicella-zoster (VZ)
|
Vesicle fluid/swab |
|
Eye
infections, conjunctivitis |
|
Adenovirus
|
Conjunctival swab (culture) |
Chlamydia trachomatis
|
Conjunctival swab (culture), slide
(DFA) |
Herpes simplex (HSV)
|
Conjunctival swab, corneal scraping |
Varicella-zoster (VZ)
|
Conjunctival swab, corneal scraping |
|
Gastrointestinal syndromes |
|
Enteroviruses
|
Stool/rectal swab |
Adenovirus 40/41
|
Stool/rectal swab |
Adenoviruses
|
Stool/rectal swab |
Rotavirus
|
Stool/rectal swab |
|
Hepatitis |
|
CMV
|
Blood (2-7 mL EDTA, purple top),
urine, throat |
EBV
|
Routine culture not available;
serologies suggested. |
HAV
|
Routine culture not available;
serologies suggested. |
HBV
|
Routine culture not available;
serologies suggested. |
|
Immunocompromised patients |
|
CMV
|
See "CMV" specimen list. |
EBV
|
Routine culture not available;
serologies suggested. |
HAV
|
Routine culture not available;
serologies suggested. |
Herpes simplex (HSV)
|
Throat, vesicle fluid/swab |
Varicella-zoster (VZ)
|
Vesicle fluid/swab |
|
Mononucleosis |
|
CMV
|
Throat, urine, blood (2-7 mL/EDTA,
purple-topped tube) |
EBV
|
Routine culture not available;
serologies suggested. |
|
Mycocarditis, pericarditis |
|
Coxsackie A and B
|
Throat swab, stool/rectal swab |
Echovirus
|
Swab, pericardial fluid/tissue |
|
Respiratory Syndromes |
|
Adenoviruses
|
Throat, NP swab |
Cytomegalovirus (CMV)
|
See "CMV" specimen list |
Enteroviruses
|
Nasal washing/secretion, throat |
Influenza
|
Nasal washing/secretion, throat or
NP swab, sputum |
Mumps
|
Throat or NP swab, urine, serology |
Parainfluenza
|
Nasal washing/secretion, NP swab,
throat |
Rhinovirus
|
Nasal or NP swab |
RSV
|
Nasal washing/secretion |
|
