Virology

A 35-year-old male presents with recurrent oral candidiasis and unexplained weight loss. Initial screening for HIV using a 4th generation ELISA test detects both p24 antigen and anti-HIV antibodies. Which of the following is the most appropriate next step for confirmation?

Which of the following enzymes is unique to retroviruses and is essential for their replication cycle, converting their RNA genome into a DNA intermediate?

A 6-month-old infant presents with fever, cough, coryza, and conjunctivitis, followed by a maculopapular rash spreading from the head downwards. The mother reports that the child has not received any vaccinations. Which of the following vaccines would have prevented this infection?

A 45-year-old renal transplant recipient on immunosuppressive therapy develops fever, leukopenia, and pneumonitis. Bronchoalveolar lavage (BAL) fluid analysis reveals cells with characteristic "owl's eye" intranuclear inclusions. Which viral infection is most likely responsible for these findings?

A patient diagnosed with chronic Hepatitis C virus (HCV) infection is being considered for antiviral therapy. Which of the following drug classes directly targets the HCV RNA-dependent RNA polymerase, inhibiting viral replication?