Final answer:
The enzyme immunoassay (EIA) is the most commonly used method for routine rotavirus detection, appropriate for clinical diagnostics of fecal samples.
Step-by-step explanation:
For routine rotavirus detection, the most commonly employed method is the enzyme immunoassay (EIA). This method is well-suited to detect the presence of rotavirus from fecal samples due to its practicality and efficiency in a clinical setting.
Other detection methods can include electron microscopy and RT-PCR; however, the enzyme immunoassay is the standard due to its ease of use and fast results. Whereas electron microscopy is used for visualization of viruses and RT-PCR is a molecular approach with high sensitivity, EIA remains a clinical favorite because it is a cost-effective and relatively quick assay to perform in diagnostic laboratories.