Were there a virus happening in the food chain, wouldn’t you want to know each time it happened, so you could track down the cause and limit further contagion?
The World Organization for Animal Health doesn’t track incidents of two pig viruses, one of which kills piglets (harmless to humans, it appears). The USDA now requires hog farmers to report and track each incident.
“USDA to Require Pig-Virus Reports,” Wall Street Journal, April 19-20, 2014 A4 http://on.wsj.com/1i4J3tD
You can manage only that which you track.