Etiological relationship between several respiratory viruses and acute respiratory diseases in 1973 in the GDR.

The role of some important respiratory viruses (influenza A, B, parainfluenza, adeno and mycoplasma) in morbidity due to acute respiratory diseases during 1973 in the GDR is analysed on account of serological data (CFR) obtained with paired sera (a -5 percent of all cases comprising all age groups) and virus isolations. The serological surveillance provides an important base for evaluating the significance of respiratory agents for the development of the morbidity due to ARD.