Viral Flashcards
4th gen HIV tests test for?
Are 1 log increases always significant?
HIV1/2 antibodies and p24
No can be increased in infection
When to drug resistance test HIV?
Naive to therapy; failing ot respond to therapy, pregnancy
NOT AFTER CESSATION OF ANTIBODY THERAPY; reverts to wild type
HIV virus tropisms?
CCR5 or CXCR4 or both
Hepatitis C is what type of virus?
Subtype in US; percent chronic?
Testing uses what areas of genome?
Enveloped RNA, positive sense, Flaviridae
Type: 1. 80% chronic
5’ NTR, Core and NS5B
Hepatitis B is what type of Virus?
T/F all the basepairs are substituted each day?
Some resistance mutations?
Hepadnavirus, partially dsDNA; Types A-H
True; DNA–>RNA–>DNA; RT lacks proof reading
V84M, A181T/V, Q215S, N236T
What is precore mutation; Hep B?
Why do we care?
G1896A; makes stop codon; blocks HBeAg
Common B-G; rare A
Lower rate of chronic liver disease
Hep B genotype that coses severe disease?
C!!
Genotype B converts from HBeAg to anti-HBe at younger age
A and B higher rate of antiviral response
HPV is what type of virus?
Oncogenes and what they interact with?
High risk?
How to detect?
Papovivirus, Double stranding circular DNA
E6 (P53); E7 (Rb)
16, 18 most common
Nucleic acid testing eg invador tech or RT-PCR; E6/E7 mRNA by TMA
Gardasil has what type protection?
HPV 6, 11, 16, 18; good at least 5 years
Tests for Zoster?
Some RUO/ASR for T-PCR; no FDA approved
CSF most commonly tested as higher loads 10e4 associated with disease.
Drugs against CMV?
CMV detection; what indicates replication?
Ganciclovir, Cidofovir, Foscarnet
Nuclic acid, Rapid-shell vial coulture, or HCMV immunoluorescence
pp65 RNA=replication
CMV mutations that cause ganciclovir resistance?
Point mutation codon 460, 520, 590-596
Molecular sequncing can detect these or plaque reduction (grow with drug)
Diseases linked to EBV infection?
PTLD seen in?
PTLD; Burkitt, EBV Hodgkin, Nasophyngeal caricnoma
BMT patients who were seronegative and donor positive; monitor by PCR viral load or in-situ hybridization
What falls in the enterovirus category?
Can you do nucleic acid amplificaton?
Negative tests associated with shorter hospital stay?
Poliovirus, Group A/B coxsackie, Echovirus, Enterovirus
Yes; 5’ noncoding is fairly conserved
No; positive tests are more associated with shorter stays
Parvovirus B19 is what type of virus?
Can you grow in cell culture?
How to ID it?
Small single stranded non-enveloped DNA; divides in erythroid precursors
No
Nucleic acids (NS-1 a and b OR VP-a) or serology Nucleic acid testing is LDT or ASR/RUO
What two viruses are polyomaviruses?
How to ID?
BK (renal) and JC (brain)
DS circular genome
Dx on biopsy with ISH, cytology, MRI or biopsy with PCR for JC
Influenza is RNA or DNA?
Found in man/animals; found in man?
RNA single stranded
A (drift and shift; pandemics) and B (drift only)
Parainfluenza what kind of virus?
SIngle negative sense RNA;; membrane has hemaglutinin and neuraminidase
No vaccine or antiviral agents
RSV what type of virus?
Treatment or vaccine?
Enveloped single stranded negative sense RNA
No tx no vaccine
Adenovirus what type?
Is treatment or vaccine widely present?
Double stranded linear DNA; 6 serologic groups
No Tx or public vaccine?
FDA cleared methodology for viral respiratory ID?
CLIA waved (most) rapid enzyme immunoassays: Highly specific sensitivity not great; Flu A/B and RSV
Also, direct fluorescence antibody assay; more sensitive with larger menu; not Waived
Influenza oseltamivir resistance mutation?
H1N1 His274Tyr
