RNAV: Astroviridae Flashcards
What disease is commonly caused by human astrovirus?
Gastroenteritis (mild, self-limiting)
How is human astrovirus transmitted?
Fecal-oral route
Contaminated food/water
Fomites
What is the distinguishing structural characteristic of astroviruses?
Star-like surface structure
What is the size and shape of astroviruses?
28-30 nm
Non-enveloped
Icosahedral
What laboratory test is used to detect astrovirus RNA along with other gastrointestinal pathogens?
Multiplex Nucleic Acid Amplification Test (NAAT)
What is the primary sample type used in astrovirus NAAT testing?
Stool samples
What are the advantages of using Multiplex NAAT for astrovirus detection?
High sensitivity and specificity; simultaneous detection of multiple pathogens
What is a major limitation of Multiplex NAAT for astrovirus detection?
Requires specialized equipment; more expensive than single-pathogen tests
What commercial test panel includes astroviruses in its enteric pathogen screening?
FilmArray Gastrointestinal Panel (BioFire Diagnostics)
What are the advantages of the FilmArray Gastrointestinal Panel for astrovirus detection?
Rapid results (~1 hour)
Easy-to-use automated system with minimal hands-on time
What is a major limitation of the FilmArray Gastrointestinal Panel?
High cost per test; cannot differentiate between recent infection and active disease
What molecular test amplifies astrovirus RNA for highly sensitive detection?
Reverse Transcription Polymerase Chain Reaction (RT-PCR)
What are the primary sample types used for RT-PCR in astrovirus detection?
Stool, occasionally serum in immunocompromised cases
What are the advantages of RT-PCR for astrovirus detection?
Highly sensitive and specific; can detect different astrovirus genotypes
What is a major limitation of RT-PCR for astrovirus detection?
Requires RNA extraction and specialized lab equipment; more time-consuming than rapid tests
What test detects astrovirus antigens or antibodies in stool samples?
Enzyme-Linked Immunosorbent Assay (ELISA)
What is a major advantage of ELISA for astrovirus detection?
Simple, cost-effective, suitable for large-scale screening
What is a major limitation of ELISA for astrovirus detection?
Lower sensitivity and specificity compared to RT-PCR; potential for false negatives in low viral load cases
