"Carrying it in duty-free bags through customs, in luggage, shipping it in the mail and carrying it on their bodies. On the commercial level, shipments are often embedded in dried fish," she said.
From there, it often finds its way into the markets of American cities that have large concentrations of immigrants from Western and Central Africa.
"We don't have a handle on how much is coming in. The perception is that we're only catching a fraction of what's actually entering the country. It is difficult to know where to search. … There aren't that many direct flights from Africa, but we're wary of connecting flights," said the CDC's McQuiston.
The risk of diseases jumping from animals to humans is very real. In addition to the SARS and bird flu epidemics out of Asia in recent years, "it is generally understood that HIV arose through contact with nonhuman primates," said Nina Marano, a veterinarian at the CDC.
Increased human contact with wild animals -- from butchering to eating -- increases the risk of infection for a host of diseases, some well-known, others less so. Simian foamy virus, a retrovirus in the same family of diseases as HIV, "is associated with people who butcher nonhuman primates," Marano said.
William Karesh, director of the Department of Field Veterinary Programs at the Wildlife Conservation Society, said that meat itself was only one arena for contact. Everyone who handled the meat -- hunters, butchers, middlemen, smugglers, consumers -- and every person in contact with the handlers was at risk for infection.
"If 500,000 animals are killed in a given year and handled by hunters, middle people and consumers, that's 1.5 billion contacts. The risk isn't in how much you eat," he said.
"It's in the numbers," he said. "A hundred years ago there wasn't this level of consumption or international travel. … That's magnified the risk and changed the odds. The risk in the U.S. is lower than in Africa, where we've seen outbreaks of Ebola hemorrhagic fever and with SARS and avian flu in Asia. … But their problem is our problem and we need to first deal with the issue overseas."
Echoing that sentiment, Healy said, "the world's a lot smaller a place than it used to be. … People are used to eating the native foods from the places they're from, and they don't know the consequence of bringing [bushmeat ] into the country, especially when it's not cooked."
Much of the bushmeat entering the United States has been cooked or smoked, but the CDC warns that cooking meat in unregulated and often unsanitary conditions does not necessarily ensure the meat is free of pathogens.
In addition to the public health issues involved, the bushmeat trade also raises important conservation and socioeconomic issues.
In many parts of Africa, wild animal populations have been "devastated" by people who have no alternative source of protein, said Karesh.
"A lack of alternatives, a population boom and better access to forests along roads cut by logging companies" have given people the desire and means to kill a diversity of wild animals, he said.
"It's getting to the point in many places where there's little wildlife left other than rodents," said Heather Eves of the bushmeat task force. "We've entered a phase in the global market that open wildlife markets are indeed a global health threat."
All of the experts who spoke to ABCNEWS.com agreed that enforcement at America's borders alone would not stem the trade. Travelers need to be educated of the risks involved in bringing bushmeat into the United States, and Africans need to be given the tools to produce sustainable and safe alternatives to bushmeat.
"Other agencies are going after the smugglers," Marano said, "but the CDC is primarily concerned with education, and we're working with foreign ministries of health and with conservation agencies."
"We need a multisector approach," said Eves, "rather than focus on strict enforcement. … Understanding the drive would help us to get at solving the problem."