摘要：Outbreaks of influenza due to the virus A/Hong Kong/1/68 (H3N2) began in 1968 and are still occurring. The haemagglutinin of this virus is different from that of the A/Singapore/1/57 virus (the “Asian” strain) but the neuraminidase antigens are the same. Between 1968 and 1971 only minor antigenic “drift” in the haemagglutinin was noted, but in recent months 2 isolates have been identified in which considerable “drift” has occurred in the haemagglutinin and in the neuraminidase antigens. One, A/Hong Kong/5/72 (H3N2), was first detected in outbreaks in Hong Kong between November 1971 and January 1972 and was predominant there and in Korea but did not become widely disseminated. The second strain, A/England/42/72 (H3N2), has been isolated in winter outbreaks in the southern hemisphere and now appears to be the predominant strain in the northern hemisphere. The characteristics of the strains are described. Full text Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (2.2M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References . 269 270 271 272 273 274 275 276 277 278
