Update in infectious diseases. Part I: Epidemiology

A number of infectious agents has been newly detected in thr last 10 years. Climatic hanges and migration have been the most important factors in thw emergence of new and old infections. Additionally, new methods for the dete ction of DNA and RNA have played an important role in the detection of agen ts difficult to culture. Relevant new bacterial pathogens are Bartonella henselae (cat scratch disea se, bacillary angiomatosis). Tropheryma whippeli (Whipple's disease) and ne w Rickettsiar. Newly detected viral pathogens include Sin-nombre virus (pul monary Hanta virus syndrome), Nipah- and Hendra virus and avian influenza. Bovine spongiform encephalopathy has been transmitted to humans causing the newly described syndrome of variant Creuzfeldt-Jakob disease. The extent o f this is not yet clear.