Laboratory Diagnosis of Viral Diseases
The clinical manifestations may be protean and nonspecific for many of the viral infections. However, they provide a clue in the diagnosis of viral infections by exclusion of common bacterial, parasitic, fungal diseases, etc. Laboratory diagnosis, therefore, plays an important role in confirming viral etiology of sus-pected viral diseases. Laboratory diagnosis for viral diseases is performed to:
a) Confirm the viral etiology of diseases for which antiviral chemotherapeutic agents are available.
b) Screen blood donors for blood-borne viral pathogens, such as hepatitis B and C, human immunodeficiency virus (HIV), etc., to prevent transmission of infection by transfu-sion of blood and blood-borne products contaminated by viruses.
c) Define the viral disease process.
d) Perform seroepidemiological studies of viral infections.
e) Monitor and detect epidemics of serious virus infections, such as influenza, encephalitis, and poliomyelitis, etc., ear-lier so as to initiate appropriate control measures to pre-vent further spread of these diseases.