1 Department of Internal Medicine, Hacettepe University School of Medicine, Ankara o6230, Turkey; Hacettepe University Vaccine Institute, Ankara, Turkey. Electronic address: mdurusu@yahoo.com.
2 Department of Clinical Microbiology and Infectious Diseases, Hacettepe University School of Medicine, Ankara o6230, Turkey; Hacettepe University Vaccine Institute, Ankara, Turkey.