How are viral infections currently identified?
Viral infections are mainly identified indirectly by detecting a patients production of specific antibody (serology). But as antibodies are only produced a week or more after the start of an infection, results are delayed for a considerable period of time. In routine laboratories only a limited number of viral pathogens can be identified directly (usually with ELISA based methods), with positive results requiring a minimum concentration of the virus to be positive. A few viruses can be identified by detecting their unique DNA or RNA, but use of this method has been mainly limited to blood donation screening for HIV and Hepatitis viruses in specialized laboratories. Virus identification by culture takes far too long and is far too expensive for routine use, and is therefore used only by reference laboratories in unusual circumstances.
