A deadly tick-borne epidemic is raging in northern Mexico. Children, like Olivia Flores Legardia's 7-year-old, are especially vulnerable. He died within days of contracting the virus, Rocky Mountain spotted fever. Now she fears for her two other children. The virus attacks the organs and is easy to misdiagnose in the first couple of days. If not treated within 3-4 days it is nearly always fatal.

Mexican and American epidemiologists and vets are working tirelessly in San Quintin, Baja California where numbers are swelling. They take tick and blood samples and educate the local population on caring for their dogs. Children have been contracting it in larger numbers because they often play with the stray dogs that roam the area's dusty streets.