Varicella virus pcr

Reportable Range:. Clin Infect Dis ;25 3 Scand J Infect Dis ;32 3 J Neurovirol ;5 2 Sauerbrei A: Varicella-zoster virus infections - antiviral therapy and diagnosis. Sauerbrei A: Diagnosis, antiviral therapy, and prophylaxis of varicella-zoster virus infections. The LightCycler instrument amplifies and monitors by fluorescence the development of target nucleic acid sequences after the annealing step during PCR cycling. This is an automated PCR system that can rapidly detect minutes amplicon development though stringent air-controlled temperature cycling in capillary cuvettes.

The detection of amplified products is based on the fluorescence resonance energy transfer FRET hybridization probe with a donor fluorophore, fluorescein, on the 3' end is excited by an external light source and emits light that is absorbed by a second hybridization probe with an acceptor fluorophore, LC-Red , at the 5' end. The acceptor fluorophore then emits a light of a different wavelength that can be measured with a signal that is proportional to the amount of specific PCR product.

Melting curve analysis is performed following PCR amplification. Starting at 45 degrees C, the temperature in the thermal chamber is slowly raised to 80 degrees C, and the fluorescence is measured at frequent intervals. Analysis of the PCR amplification and probe melting curves is accomplished through the use of LightCycler software. Dhiman N, Wright PA, Espy MJ, et al: Concurrent detection of herpes simplex and varicella-zoster viruses by polymerase chain reaction from the same anatomic location.

Diagn Microbiol Infect Dis Aug;70 4 doi: J Clin Microbiol ;38[9] Monday through Saturday. This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. Excel Pdf. Normal Reports Abnormal Reports. Test Catalog Test Catalog. Contact Search. Search Cancel. Home Test Catalog Overview. Test Catalog. Order This Test. Useful For Suggests clinical disorders or settings where the test may be helpful. Method Name A short description of the method used to perform the test.

Reporting Name Lists a shorter or abbreviated version of the Published Name for a test. Aliases Lists additional common names for a test, as an aid in searching. Specimen Type Describes the specimen type validated for testing. Specimen Required Defines the optimal specimen required to perform the test and the preferred volume to complete testing. Specimen Minimum Volume Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory.

Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected. To make a laboratory diagnosis of VZV infection using polymerase chain reaction PCR method, the presence of the virus DNA should be demonstrated in tissues, vesicular fluid, maculopapular lesions, or crusts from lesions. The following methods are recommended. Crusts can be lifted off the skin a glass slide is also useful for this purpose and transferred directly into break-resistant, snap-cap or screw-top tubes.

For some disease presentations with a suspected VZV etiology e. Blood or CSF can be shipped on cold packs or frozen. Biopsy tissue is preferred shipped frozen and, if available, unfixed. In rare cases involving severe complications or death, other types of specimens e. When possible, liquid specimens should be shipped frozen.

These items are available through distributors of scientific laboratory products, such as Fisher Scientific and WVR International. Note: This information applies to testing for shingles zoster as well as chickenpox. Skip directly to site content Skip directly to page options Skip directly to A-Z link. Chickenpox Varicella. Section Navigation. Facebook Twitter LinkedIn Syndicate. Minus Related Pages. On This Page. Collect a sufficient quantity of blood onto both of the defined areas on the filter strip so that the spot expands to the circular border.

Filter strips will be made available to state and local public health laboratories and to the varicella surveillance project office in your area on request. Permit the specimen to air dry completely. Do not allow different strips to come into contact with each other while wet. Place the strips in a sealable plastic bag. Vesicular lesions or scabs, if present, are the best for sampling. Adequate collection of specimens from maculopapular lesions in vaccinated people can be challenging.

However, one study Evaluation of Laboratory Methods for Diagnosis of Varicella pdf icon external icon comparing a variety of specimens from the same patients vaccinated with one dose suggests that maculopapular lesions collected with proper technique can be highly reliable specimen types for detecting VZV.

Other sources such as nasopharyngeal secretions, saliva, blood, urine, bronchial washings, and cerebrospinal fluid are less likely to provide an adequate sample and can often lead to false negative results. Other viral isolation techniques for confirming varicella are direct fluorescent antibody assay DFA and viral culture.

However, these techniques are generally not recommended because they are less sensitive than PCR and, in the case of viral culture, will take longer to generate results. IgM serologic testing is considerably less sensitive than PCR testing of skin lesions.

IgM serology can provide evidence for a recent active VZV infection, but cannot discriminate between a primary infection and reinfection or reactivation from latency since specific IgM antibodies are transiently produced on each exposure to VZV. IgM tests are also inherently prone to poor specificity. Paired acute and convalescent sera showing a four-fold rise in IgG antibodies have excellent specificity for varicella, but are not as sensitive as PCR of skin lesions for diagnosing varicella.

People with prior history of vaccination or disease history may have very high baseline titers, and may not achieve a four-fold increase in the convalescent sera. The usefulness of this method for diagnosing varicella is further limited as it requires two office visits.

For both unvaccinated and vaccinated people, PCR is the most reliable method for confirming infection. Examples of possible varicella vaccine-adverse events for which PCR genotyping for VZV can be useful include varicella or a varicella-related complication in a vaccinated person 7 to 42 days after vaccination, herpes zoster in a vaccinated person, and suspected secondary vaccine-strain VZV transmission.

A single serologic IgG test can be used to determine if a person has antibodies to VZV from past varicella disease or who may be candidates for varicella-zoster immune globulin VZIG.