Histologists use a range of techniques to identify mixed infections. Histological staining methods like Gram staining, Periodic Acid-Schiff (PAS) staining, and Ziehl-Neelsen staining can help differentiate between various pathogens. Additionally, immunohistochemistry (IHC) and in situ hybridization (ISH) are often employed to detect specific antigens or genetic material from different microorganisms.