林有嘉 醫師 CLO2( Chlorine Dioxide ) 對A型流行性感冒(H1N1)的預防效果

Protective effect of low-concentration chlorine dioxide gas against influenza A virus infection
低濃度Chlorine Dioxide氣體對A型流行性感冒的預防效果

作者：Norio Ogata and Takashi ShibataResearch Institute, Taiko Pharmaceutical Co. Ltd, 3-34-14 Uchihonmachi, Suita , Osaka 564-0032, Japan
出處：Journal of General Virology (2008), 89, 60–67

Influenza virus infection is one of the major causes of human morbidity and mortality. Between humans, this virus spreads mostly via aerosols excreted from the respiratory system. Current means of prevention of influenza virus infection are not entirely satisfactory because of their limited efficacy. Safe and effective preventive measures against pandemic influenza are greatly needed. We demonstrate that infection of mice induced by aerosols of influenza A virus was prevented by chlorine dioxide (ClO2) gas at an extremely low concentration (below the long-term permissible exposure level to humans, namely 0.1 p.p.m.). Mice in semi-closed cages were exposed to aerosols of influenza A virus (1 LD50) and ClO2 gas (0.03 p.p.m.) simultaneously for 15 min. Three days after exposure, pulmonary virus titre (TCID50) was 102.6± 1.5 in five mice treated with ClO2, whilst it was 106.7± 0.2 in five mice that had not been treated (P=0.003). Cumulative mortality after 16 days was 0/10 mice treated with ClO2 and 7/10 mice that had not been treated (P=0.002). In in vitro experiments, ClO2 denatured viral envelope proteins (haemagglutinin and neuraminidase) that are indispensable for infectivity of the virus, and abolished infectivity. Taken together, we conclude that ClO2 gas is effective at preventing aerosol-induced influenza virus infection in mice by denaturing viral envelope proteins at a concentration well below the permissible exposure level to humans. ClO2 gas could therefore be useful as a preventive means against influenza in places of human activity without necessitating evacuation.

流感病毒感染是人類發病和死亡的主要原因之一。此種病毒在人群間主要經由空氣傳播。當今流感病毒感染的預防方法效果有限，不甚令人滿意；因此安全和有效的大流行性流感預防措施是非常被需要的。本動物（小鼠）研究證明經由空氣傳染的A型流感可以極低濃度的chlorine dioxide（ClO2）來預防（低於人類可允許的長期暴露濃度“0.1 p.p.m.”）。小鼠在半密閉的籠裡同時暴露於A型流感病毒（流感病毒株A/PR/8/34〈H1N1〉)（1 LD50）和ClO2氣體（0.03 p.p.m.）15分鐘。暴露3天後，給予ClO2的5隻老鼠（治療組）的肺部病毒滴定量（TCID50）是102.6±1.5，而未給予ClO2的5隻小鼠（對照組）則為106.7±0.2（P=0.003）。16天後的累積死亡率是治療組的0/10和對照組的7/10（P=0.002）。在體外試驗（流感病毒株A/New Caledonia/20/99〈H1N1〉)中，ClO2可使病毒封套蛋白（血凝素〈haemagglutinin, HA〉和神經胺酸酶〈neuraminidase, NA〉；病毒傳染的必需物質）變性，並且徹底破壞病毒的傳染性。
總言之，低於人類可允許暴露濃度的ClO2可藉由使病毒封套蛋白變性，有效預防小鼠經空氣傳染的流行性感冒。因此ClO2氣體應可用於人群活動地點的流感預防，且不需疏散人群。