Pneumonia ranks as the third leading cause of death in Japan. About 97% of patients who die because of pneumonia are elderly, with aspiration generally thought to be involved in the majority of cases of pneumonia in elderly. Once an elderly individual contracts pneumonia, their physical function often declines and their activities of daily living diminish with hospital admission, even in individuals with no underlying disorders. Prolonged confinement to a bed and immobility leads to weakening of the legs and back, making it difficult for elderly patients to attend daily outpatient clinics, often leading to admission to nursing facilities for the aged instead of returning to their own home, even after curative treatment for pneumonia. Most such patients repeatedly develop pneumonia and repeated antibiotic treatment enhances the risk of the emergence of resistant organisms. It is beyond doubt, therefore, that prevention of pneumonia is of vital importance in the elderly.

Influenza A and B viruses possess an enzyme “sialidase” that cleavages terminal sialic acid from glycochains. These viral sialidase proteins are highly expressed on the virus infected cells. We developed sialidase imaging probe “BTP3-Neu5Ac” that enables histochemical fluorescence staining of sialidase activity. BTP3-Neu5Ac was able to perform speedy and easy fluorescence imaging of these virus infected cells, with no needs of specific antibody and cell fixation. In addition, combination use of anti-influenza drugs (sialidase inhibitors) and BTP3-Neu5Ac resulted in selective fluorescence imaging for detection and high-efficiency isolation of drugresistant virus. Fluorescence imaging of drug-resistant virus will be a powerful method for study of the drug-resistance mechanism, for monitoring of drug-resistant viruses. A novel tool for fluorescence imaging of viral sialidase activity is described in this review.

The susceptibility of 1578 Streptococcus pneumoniae strains isolated from pediatric patients at Asahikawa Kosei Hospital between 2011 and 2015 was tested to penicillin G (PCG), cefotaxime (CTX), ceftriaxone (CTRX), cefditoren (CDTR), meropenem (MEPM), erythromycin (EM) and levofloxacin (LVFX). Although no significant differences were observed, the percentage of strains with a minimal inhibitory concentration (MIC) of PCG of <0.1μg/mL increased from 55.5% (2011) to 64.0% (2015), whereas that of strains with MIC of ≥2μg/mL decreased from 14.8% to 9.5%. From 2011 to 2015, the percentage of strains with MIC≤0.12μg/mL increased from 18.9% to 28.9% for CTX, from 20.5% to 30.2% for CTRX, from 29.2% to 40.9% for CDTR, and from 69.6% to 80.6% for MEPM. EM-resistant strains with MIC ≥2μg/mL accounted for as much as approximately 90% each year. One LVFX-resistant strain with MIC ≥8μg/mL has been detected each year since 2013.