Medical Laboratory Professionals' Association of Ontario (MLPAO) Practice Exam

Polymerase chain reaction (PCR) testing is a widely used molecular technique that amplifies specific segments of DNA or RNA, allowing for the detection of various pathogens. One of the significant advantages of PCR is its ability to identify viruses with high sensitivity and specificity, making it valuable in clinical diagnostics.

When it comes to viruses, PCR can be used to detect a range of viral infections, including but not limited to HIV, influenza viruses, coronaviruses like SARS-CoV-2 (responsible for COVID-19), and many others. This versatility stems from PCR's capacity to target the genetic material of viruses directly, enabling quick and accurate diagnosis even in cases with low viral loads.

In contrast, the other options presented do not encompass the range of pathogens that PCR can effectively detect. Limiting PCR testing solely to respiratory viruses excludes its application for numerous other viral infections. Suggesting that PCR is specific only to bacterial infections or to parasites and fungal infections is misleading, as traditional PCR is not typically the method of choice for these types of pathogens. Rather, PCR's broad applicability to various viruses is what makes it a critical tool in modern virology, underscoring the correctness of recognizing its use in detecting a wide range of viral pathogens.