Mexico said on Tuesday it has restricted live pork imports from the United States, citing an outbreak of a deadly piglet virus that has spread north of the border.

Mexico's Agriculture Ministry said it would review imports on a case by case basis, and said it had not detected the virus in Mexico.

It added that pigs imported from the United States prior to May 17 would be quarantined and closely observed. It is checking all lots of pigs imported from the United States during the past three months.

Porcine Epidemic Diarrhea Virus, a swine virus deadly to young pigs, and never before seen in North America, has spiked to 199 sites in 13 states in the United States.

Most often fatal to very young pigs, the virus causes diarrhea, vomiting and dehydration. It also sickens older hogs, though their survival rate tends to be high.

However, the virus does not pose a health risk to humans or other animals and the meat from infected pigs is safe for people to eat, according to federal officials in the United States and livestock economists. (Reporting by Adriana Barrera; Writing by Simon Gardner and Phil Berlowitz)