Livestockassociated Methicillin-Susceptible Staphylococcus aureus ST398 Infection in Woman, ColombiaTo the Editor: Staphylococcus aureus causes health care-and community-associated infections worldwide in humans and animals.It also asymptomatically colonizes a large proportion (20%-60%) of otherwise healthy individuals.In recent years, various countries have reported an increasing number of humans infected with livestock-associated S. aureus multilocus sequence type (ST) 398, which suggests that this strain is emerging in community and health care settings (1).Methicillinresistant S. aureus (MRSA) ST398 has received particular attention as a causative agent of infection in pigs, dogs, horses, cattle, and poultry.Colonization and infection in humans have also been described in Europe (2), Asia (3), Canada (4), and the United States (5), particularly among persons with frequent exposure to animals, such as farmers, veterinarians, and their household members.However, infections with MRSA ST398 and methicillin-susceptible S. aureus (MSSA) ST398 have recently been described in persons with no history of contact with livestock (6-10).We report infection of a woman with MSSA ST398 in Colombia, South America.On November 3, 2009, this 82-year-old woman was admitted to the emergency unit of the Hospital Universitario San Vicente Fundación in Medellín, reporting a 15-day history of fever, dyspnea, and pain in her left leg.She lived in a rural area and reported previous contact with dogs and chickens.Her medical history included diabetes mellitus,