Answer: E
Influenza virus may expose potential binding sites for bacteria, impair mucociliary function, up-regulate bacterial toxin genes and lead to immunodysregulation. At the same time, it has also been found that Staphylococcus aureus protease helps to cleave the haemagglutinin and in turn increases viral replication.
References
A. Childs RA, Palma AS, Wharton S, Matrosovich T, Liu Y, Chai W, Campanero-Rhodes MA, Zhang Y, Eickmann M, Kiso M, Hay A, Matrosovich M, Feizi T.Receptor-binding specificity of pandemic influenza A (H1N1) 2009 virus determined by carbohydrate microarray. Nat Biotechnol. 2009 Sep;27(9):797-9. No abstract available.
B. Itoh Y, Shinya K, Kiso M, Watanabe T, Sakoda Y, Hatta M, Muramoto Y, Tamura D, Sakai-Tagawa Y, Noda T, Sakabe S, Imai M, Hatta Y, Watanabe S, Li C, Yamada S, Fujii K, Murakami S, Imai H, Kakugawa S, Ito M, Takano R, Iwatsuki-Horimoto K, Shimojima M, Horimoto T, Goto H, Takahashi K, Makino A, Ishigaki H, Nakayama M, Okamatsu M, Takahashi K, Warshauer D, Shult PA, Saito R, Suzuki H, Furuta Y, Yamashita M, Mitamura K, Nakano K, Nakamura M, Brockman-Schneider R, Mitamura H, Yamazaki M, Sugaya N, Suresh M, Ozawa M, Neumann G, Gern J, Kida H, Ogasawara K, Kawaoka Y. In vitro and in vivo characterization of new swine-origin H1N1 influenza viruses. Nature. 2009 Aug 20;460(7258):1021-5. Free text available here
C. a. Hancock K, Veguilla V, Lu X, Zhong W, Butler EN, Sun H, Liu F, Dong L, DeVos JR, Gargiullo PM, Brammer TL, Cox NJ, Tumpey TM, Katz JM. N Engl J Med. 2009 Nov 12;361(20):1945-52. Epub 2009 Sep 10. Cross-reactive antibody responses to the 2009 pandemic H1N1 influenza virus.
b. Zhu FC, Wang H, Fang HH, Yang JG, Lin XJ, Liang XF, Zhang XF, Pan HX, Meng FY, Hu YM, Liu WD, Li CG, Li W, Zhang X, Hu JM, Peng WB, Yang BP, Xi P, Wang HQ, Zheng JS. A novel influenza A (H1N1) vaccine in various age groups. New Engl J Med. 2009 Dec 17;361(25):2414-23. Epub 2009 Oct 21.
c. Liang XF, Wang HQ, Wang JZ, Fang HH, Wu J, Zhu FC, Li RC, Xia SL, Zhao YL, Li FJ, Yan SH, Yin WD, An K, Feng DJ, Cui XL, Qi FC, Ju CJ, Zhang YH, Guo ZJ, Chen PY, Chen Z, Yan KM, Wang Y. Safety and immunogenicity of 2009 pandemic influenza A H1N1 vaccines in China: a multicentre, double-blind, randomised, placebo-controlled trial. Lancet. 2010 Jan 2;375(9708):56-66. Epub 2009 Dec 15.
D. Gordon CL, Johnson PD, Permezel M, Holmes NE, Gutteridge G, McDonald CF, Eisen DP, Stewardson AJ, Edington J, Charles PG, Crinis N, Black MJ, Torresi J, Grayson ML. Association between severe pandemic 2009 influenza A (H1N1) virus infection and immunoglobulin G(2) subclass deficiency. Clin Infect Dis. 2010 Mar 1;50(5):672-8.
E. Tashiro M, Ciborowski P, Klenk HD, Pulverer G, Rott R. Role of Staphylococcus protease in the development of influenza pneumonia. Nature. 1987 Feb 5-11;325(6104):536-7.