Beschreibung:
<jats:p>Changes in the inhibitory properties of human nasal mucus were found to be positively correlated with objective signs of influenza virus infection during the 1950 epidemic. In approximately 80% of the cases the inhibitor index was significantly increased during the acute stage of the disease, and reverted to normal during convalescence.</jats:p><jats:p>Various respiratory diseases other than epidemic influenza did not cause similar changes.</jats:p><jats:p>Examination of the inhibitory pattern of nasal mucus is proposed as a presumptive test for influenza virus infection, and its merits are discussed under the headings of reproducibility, specificity and sensitivity.</jats:p>