TEN cows in Sarapiquí, in north-central Costa Rica, have been struck down by anthrax. Ministry of Agriculture (MAG) officials do not expect more to be affected, or that the outbreak will expand to other areas of the country, the daily La Nación reported.Anthrax gained notoriety in 2001 as a suspected biological weapon that left five dead in the United States when it was sent through the mail. (The cases remain unsolved.) However, farmers have dealt with the organism for decades. Spores that cause anthrax can sit in the soil for as long as 100 years and are released during certain environmental conditions such as precipitation followed by high heat and humidity.Humans can contract the disease by inhaling spores, by allowing an open wound to come into contact with blood from an infected animal, or by consuming an infected animal. Such incidents are unlikely, according to animal health officials, because the animals usually die within hours.Five people from the cattle ranch have been observed by doctors and have not shown any sign of illness, according to La Nación.Although contagious, anthrax usually stays localized in one area, MAG Animal Health assistant director Ligia Quirós told the daily.The bacteria have been in Costa Rica for decades, and every year there are outbreaks throughout the country.An anthrax outbreak in the United States in recent months has killed more than 500 cattle in the Great Plains region.