Table 4.

Indications for the use of diagnostic EM

Indication	Example
Rapid viral diagnosis	Critical epidemiological or clinical conditions, e.g. suspect of emerging viral diseases or need for fast diagnosis in immuno-compromised individuals
Abbreviation of classical cell culture diagnosis	Unknown CPE
Search for unknown or undetectable viruses	Failure or lack of other diagnostic techniques
Need for ‘catch-all-method’	Lack of clinical data or broad group of suspected agents (e.g. in diarrhea)
Quality control in industrial processes	Following GMP rules in the production of biologicals, e.g. search for contaminants in cell culture based vaccine production