Microbiologist: A lethal strain of salmonella recently showed up in a European country, causing an outbreak of illness that killed two people and infected 27 others. Investigators blame the severity of the outbreak on the overuse of antibiotics , since the salmoella bacteria tested were shown to be drug-resistant. But this is unlikely because patients in the country where the outbreak occurred cannot obtain antibiotics to treat illness without a prescription, and the country's doctors prescribe antibiotics lesss readily than do doctors in any other European country.