Travelers entering the United States are required to declare at customs whether or not they have been on a farm while traveling.

Dr Paul Sundberg, the Executive Director of the Swine Health Information Center, says the customs agents do a great job but it is known that there are times when people will go through that process but will be passed through without being diverted through secondary screening.

Dr Sundberg says: "The procedure is the declaration by the passenger and that's not just US passengers, that's all passengers."

Any time anybody comes into the country they pass through customs and in that declaration either verbally, by a kiosk or on a written form they are asked if they have been farms while they've been travelling and so that declaration needs to be made, he explains.

He says: "Then the customs agent questions the person about that event and, if they decide that person that's coming in could be a risk, through either carrying a foreign animal disease directly on their shoes, on their person or through their baggage, they will pull them off for further inspection.

"What we want to do is we want to make sure it is as thorough as possible."

That's essentially what it amounts to.

Dr Sundberg emphasises that it is not necessarily that there's anything bad is happening.

"But we want to make sure that everybody that goes through that process of coming from another country, ASF infected or not, is always screened if they declare they have been on farm and make sure we're as safe with bringing things into the country," he says.

Dr Sundberg Sundberg encourages travelers who declare at customs that they have been on a farm and are passed through without further screening to contact him directly at the Swine Health Information Center.

He says that information will be compiled and shared with the Department of Homeland Security.

As reported by Bruce Cochrane for Farmscape.ca