povidone-iodine and Influenza--Human

Increasing evidence has linked the anaerobic bacteria forming periodontopathic biofilms with aspiration pneumonia in elderly persons. In experiments designed to eliminate the potent respiratory pathogens forming biofilms in the oral cavity, we have shown that the mechanical and chemical oral cleansing using povidone-iodine effectively reduced the detection rates and numbers of methicillin-sensitive Staphylococcus species, Streptococcus pneumoniae, and Haemophilus influenzae in patients scheduled to undergo oral surgery requiring endotracheal intubation. We confirmed the pathogenicity of periodontopathic anaerobic bacteria for aspiration pneumonia in an experimental mouse model. Based upon the finding of the coexistence of Porphyromonas gingivalis with Treponema denticola in chronic periodontitis lesions, we innoculated a mixed culture of P. gingivalis and T. denticola into the mouse trachea; the resulting infection induced inflammatory cytokine production and caused pneumonia. In another series of investigations, professional oral health care (POHC), mainly cleansing administered by dental hygienists once a week for 24 months to elderly persons requiring daily care, resulted in the reduction of the number of total anaerobes, Candida albicans, and Staphylococcus species and in the number of cases of fatal aspiration pneumonia. We also found that the POHC treatment of elderly persons for 6 months in the winter season reduced the salivary levels of protease, trypsin-like activity, and neuraminidase and also decreased the frequency of influenza cases.

Topics: Aged; Animals; Bacteria, Anaerobic; Dental Care for Aged; Dental Scaling; Humans; Influenza, Human; Mice; Pneumonia, Aspiration; Porphyromonas gingivalis; Povidone-Iodine; Toothbrushing; Treponema denticola

Personal protective equipment (PPE), including medical masks, should be worn for preventing the transmission of respiratory pathogens via infective droplets and aerosols. In medical masks, the key layer is the filter layer, and the melt-blown nonwoven fabric (NWF) is the most used fabric. However, the NWF filter layer cannot kill or inactivate the pathogens spread via droplets and aerosols. Povidone-iodine (PVP-I) has been used as an antiseptic solution given its potent broad-spectrum activity against pathogens. To develop PPE (e.g., medical masks) with anti-pathogenic activity, we integrated PVP-I into nylon-66 NWF. We then evaluated its antiviral activity against influenza A viruses by examining the viability of Madin-Darby canine kidney (MDCK) cells after inoculation with the virus strains exposed to the PVP-I-integrated nylon-66 NWF. The PVP-I nylon-66 NWF protected the MDCK cells from viral infection in a PVP-I concentration-dependent manner. Subsequently, we found to integrate PVP-I into nylon-66 and polyurethane materials among various materials. These PVP-I materials were also effective against influenza virus infection, and treatment with PVP-I nylon-66 NWF showed the highest cell survival among all the tested materials. PVP-I showed anti-influenza A virus activity when used in conjunction with PPE materials. Moreover, nylon-66 NWF integrated with PVP-I was found to be the best material to ensure anti-influenza activity. Therefore, PVP-I-integrated masks could have the potential to inhibit respiratory virus infection. Our results provide new information for developing multi-functional PPEs with anti-viral activity by integrating them with PVP-I to prevent the potential transmission of respiratory viruses.

Topics: Animals; Dogs; Humans; Influenza, Human; Nylons; Orthomyxoviridae; Povidone-Iodine; Respiratory Aerosols and Droplets

Depending on the strain, influenza A virus causes animal, zoonotic, pandemic, or seasonal influenza with varying degrees of severity. Two surface glycoprotein spikes, hemagglutinin (HA) and neuraminidase (NA), are the most important influenza A virus antigens. NA plays an important role in the propagation of influenza virus by removing terminal sialic acid from sialyl decoy receptors and thereby facilitating the release of viruses from traps such as in mucus and on infected cells. Some NA inhibitors have become widely used drugs for treatment of influenza. However, attempts to develop effective and safe NA inhibitors that can be used for treatment of anti-NA drugs-resistant influenza viruses have continued. In this chapter, we describe the following updates on influenza A NA inhibitor development: (i) N-acetylneuraminic acid (Neu5Ac)-based derivatives, (ii) covalent NA inhibitors, (iii) sulfo-sialic acid analogs, (iv) N-acetyl-6-sulfo-β-D-glucosaminide-based inhibitors, (v) inhibitors targeting the 150-loop of group 1 NAs, (vi) conjugation inhibitors, (vii) acylhydrazone derivatives, (viii) monoclonal antibodies, (ix) PVP-I, and (x) natural products. Finally, we provide future perspectives on the next-generation anti-NA drugs.

Topics: Animals; Antibodies, Monoclonal; Antiviral Agents; Biological Products; Hemagglutinins; Humans; Influenza A virus; Influenza, Human; N-Acetylneuraminic Acid; Neuraminidase; Povidone-Iodine

Influenza virus infection causes significant morbidity and mortality and has marked social and economic impacts throughout the world. The influenza surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA), act cooperatively to support efficient influenza A virus replication and provide the most important targets for anti-influenza chemotherapy. In this study, povidone-iodine (PVP-I), which has a broad-spectrum microbicidal property, was examined for its inhibitory effects against influenza virus infection in MDCK cells and the mechanisms of PVP-I action on HA and NA were revealed.. Results obtained using a novel fluorescence- and chromogenic-based plaque inhibition assay showed that 1.56 mg/ml PVP-I inhibited infections in MDCK cells of human (8 strains) and avian (5 strains) influenza A viruses, including H1N1, H3N2, H5N3 and H9N2, from 23.0-97.5%. A sialidase inhibition assay revealed that PVP-I inhibited N1, N2 and N3 neuraminidases with IC50 values of 9.5-212.1 microg/ml by a mixed-type inhibition mechanism. Receptor binding inhibition and hemagglutinin inhibition assays indicated that PVP-I affected viral hemagglutinin rather than host-specific sialic acid receptors.. Mechanisms of reduction of viral growth in MDCK cells by PVP-I involve blockade of viral attachment to cellular receptors and inhibition of viral release and spread from infected cells. Therefore, PVP-I is useful to prevent infection and limit spread of human and avian influenza viruses.

Topics: Animals; Antiviral Agents; Birds; Cell Line; Chick Embryo; Guinea Pigs; Hemagglutination; Hemagglutinin Glycoproteins, Influenza Virus; Humans; Influenza A virus; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H3N2 Subtype; Influenza A Virus, H5N1 Subtype; Influenza A Virus, H9N2 Subtype; Influenza in Birds; Influenza, Human; Neuraminidase; Povidone-Iodine

Topics: Adolescent; Adult; Aged; Female; Humans; Influenza, Human; Male; Middle Aged; Pharmaceutical Preparations; Pharynx; Povidone-Iodine

On January 12, 2004, an outbreak of highly pathogenic avian influenza, caused by the H5N1 strain, occurred in a one-layer flock in Yamaguchi Prefecture, Japan. It had been 79 years since the last outbreak of avian influenza was confirmed in Japan. By February, 3 additional outbreaks had occurred (1 in Oita Prefecture and 2 in Kyoto Prefecture). Influenza viruses are enveloped viruses and are relatively sensitive to inactivation by lipid solvents, such as detergents. Infectivity is also rapidly destroyed by ether, sodium hypochlorite, povidone-iodine (PVP-I), peracetic acid and alcohol. However, these antiviral effects were only tested against human influenza A viruses. In the present study, the antiviral activity of PVP-I products against H5, H7 and H9 avian influenza A viruses, which had recently been transmitted to humans, were investigated.. The in vitro antiviral activity of PVP-I products (2% PVP-I solution, 0.5% PVP-I scrub, 0.25% PVP-I palm, 0.23% PVP-I gargle, 0.23% PVP-I throat spray and 2% PVP-I solution for animals) against avian influenza A viruses [a highly pathogenic avian influenza virus, A/crow/Kyoto/T2/04 (H5N1; 10(6.5) EID(50)/0.1 ml), and 3 low pathogenic avian influenza A viruses, A/whistling swan/Shimane/499/838 (H5N3; 10(4.8) EID(50)/0.1 ml), A/whistling swan/Shimane/42/80 (H7N7; 10(5.5) EID(50)/0.1 ml) and A/duck/Hokkaido/26/99 (H9N2; 10(4.8) EID(50)/0.1 ml)] were investigated using embryonated hen's eggs.. Viral infectious titers were reduced to levels below the detection limits by incubation for only 10 s with the PVP-I products used in this study. These results indicate that PVP-I products have virucidal activity against avian influenza A viruses. Therefore, the PVP-I products are useful in the prevention and control of human infection by avian influenza A viruses.

Topics: Animals; Anti-Infective Agents, Local; Antiviral Agents; Asia; Chick Embryo; Chickens; Disease Outbreaks; Humans; Influenza A virus; Influenza A Virus, H5N1 Subtype; Influenza A Virus, H7N7 Subtype; Influenza A Virus, H9N2 Subtype; Influenza in Birds; Influenza, Human; Japan; Netherlands; Povidone-Iodine

Encouragement of gargling is important for the control of opportunistic and community-acquired infections. In hospitals, a povidone-iodine (PVP-I) gargle is used frequently. However, at pharmacies in the community a variety of gargles containing various ingredients are now available. In view of this, we conducted a study to compare the bactericidal activities of a PVP-I gargle with those of other commercially available gargles. In addition, we asked about the feeling after use by questionnaire. At middle schools in our city, we investigated whether the encouragement to use the PVP-I gargle had an effect on the absence rate from school due to common cold and influenza.. In vitro, using 3 strains of gram-positive and 4 strains of gram-negative bacteria as the test strains, the bactericidal activities of the PVP-I, chlorhexidine gluconate (CHG) and cetylpiridium chloride gargles (CPC) were compared by the contact test method. In vivo, with subjects in groups of 6 each, the reduction rate in the oral bacterial count after gargling as compared to the baseline count before gargling was determined and compared among the 3 gargling agents used. In addition, a questionnaire study was conducted to compare the feeling after use of the 3 gargling agents. Whether the absence rate due to common cold and influenza changed by encouraging the use of the PVP-I gargle was determined by comparing a middle school where the PVP-I gargle was used and other middle schools where it was not.. (1) PVP-I killed all the test strains after 30 s of exposure. (2) The mean reduction rate in bacterial count immediately after gargling was 99.4% for PVP-I, 59.7% for CHG and 97.0% for CPC. (3) Findings of the questionnaire study revealed that the PVP-I gargle was evaluated highest in terms of taste, feeling after gargling and odor among all the gargles tested. (4) At the middle school where the use of the PVP-I gargle was encouraged, the absence rate due to common cold and influenza was significantly lower as compared to those at middle schools where another gargle was used.. Of the 3 gargles tested, PVP-I showed the highest bactericidal rate and the highest reduction rate in oral bacterial count. Encouragement of the use of the PVP-I gargle contributed to the decrease in absence rates due to common cold and influenza, indicating that encouragement of gargling with PVP-I is useful for the prevention of common cold and influenza.

Topics: Adolescent; Adult; Anti-Infective Agents, Local; Cetylpyridinium; Common Cold; Humans; Influenza, Human; Mouthwashes; Povidone-Iodine