Skip to main content Accessibility help
×
Home

Infection Control Preparedness for Human Infection With Influenza A H7N9 in Hong Kong

  • Vincent C. C. Cheng (a1) (a2), Josepha W. M. Tai (a2), W. M. Lee (a2), W. M. Chan (a3), Sally C. Y. Wong (a1), Jonathan H. K. Chen (a1), Rosana W. S. Poon (a1), Kelvin K. W. To (a1), Jasper F. W. Chan (a1), P. L. Ho (a1), K. H. Chan (a1) and K. Y. Yuen (a1)...

Abstract

OBJECTIVE

To assess the effectiveness of infection control preparedness for human infection with influenza A H7N9 in Hong Kong.

DESIGN

A descriptive study of responses to the emergence of influenza A H7N9.

SETTING

A university-affiliated teaching hospital.

PARTICIPANTS

Healthcare workers (HCWs) with unprotected exposure (not wearing N95 respirator during aerosol-generating procedure) to a patient with influenza A H7N9.

METHODS

A bundle approach including active and enhanced surveillance, early airborne infection isolation, rapid molecular diagnostic testing, and extensive contact tracing for HCWs with unprotected exposure was implemented. Seventy HCWs with unprotected exposure to an index case were interviewed especially regarding their patient care activities.

RESULTS

From April 1, 2013, through May 31, 2014, a total of 126 (0.08%) of 163,456 admitted patients were tested for the H7 gene by reverse transcription-polymerase chain reaction per protocol. Two confirmed cases were identified. Seventy (53.8%) of 130 HCWs had unprotected exposure to an index case, whereas 41 (58.6%) and 58 (82.9%) of 70 HCWs wore surgical masks and practiced hand hygiene after patient care, respectively. Sixteen (22.9%) of 70 HCWs were involved in high-risk patient contacts. More HCWs with high-risk patient contacts received oseltamivir prophylaxis (P=0.088) and significantly more had paired sera collected for H7 antibody testing (P<0.001). Ten (14.3%) of 70 HCWs developed influenza-like illness during medical surveillance, but none had positive results by reverse transcription-polymerase chain reaction. Paired sera was available from 33 of 70 HCWs with unprotected exposure, and none showed seroconversion against H7N9.

CONCLUSIONS

Despite the delay in airborne precautions implementation, no patient-to-HCW transmission of influenza A H7N9 was demonstrated.

Infect Control Hosp Epidemiol 2015;36(1): 87–92

Copyright

Corresponding author

Address correspondence to K. Y. Yuen, MD, FRCPath, Department of Microbiology, Queen Mary Hospital, Hong Kong, China (kyyuen@hkucc.hku.hk).

References

Hide All
1.Gao, R, Cao, B, Hu, Y, et al. Human infection with a novel avian-origin influenza A (H7N9) virus. N Engl J Med 2013;368:18881897.
2.Chen, Y, Liang, W, Yang, S, et al. Human infections with the emerging avian influenza A H7N9 virus from wet market poultry: clinical analysis and characterisation of viral genome. Lancet 2013;381:19161925.
3.Meng, Z, Han, R, Hu, Y, et al. Possible pandemic threat from new reassortment of influenza A(H7N9) virus in China. Euro Surveill, 19:20699.
4.Xu, L, Bao, L, Deng, W, et al. Novel avian-origin human influenza A(H7N9) can be transmitted between ferrets via respiratory droplets. J Infect Dis 2014;209:551556.
5.Richard, M, Schrauwen, EJ, de Graaf, M, et al. Limited airborne transmission of H7N9 influenza A virus between ferrets. Nature 2013;501:560563.
6.Jie, Z, Xie, J, He, Z, et al. Family outbreak of severe pneumonia induced by H7N9 infection. Am J Respir Crit Care Med 2013;188:114115.
7.Qi, X, Qian, YH, Bao, CJ, et al. Probable person to person transmission of novel avian influenza A (H7N9) virus in Eastern China, 2013: epidemiological investigation. BMJ 2013;347:4752.
8.Liu, T, Bi, Z, Wang, X, et al. One family cluster of avian influenza A(H7N9) virus infection in Shandong, China. BMC Infect Dis 2014;14:98.
9.Li, Q, Zhou, L, Zhou, M, et al. Epidemiology of human infections with avian influenza A(H7N9) virus in China. N Engl J Med 2014;370:520532.
10.Cheng, VC, Tai, JW, Ho, SK, et al. Introduction of an electronic monitoring system for monitoring compliance with Moments 1 and 4 of the WHO “My 5 Moments for Hand Hygiene” methodology. BMC Infect Dis 2011;11:151.
11.Cheng, VC, Tai, JW, Wong, LM, et al. Prevention of nosocomial transmission of swine-origin pandemic influenza virus A/H1N1 by infection control bundle. J Hosp Infect 2010;74:271277.
12.To, KK, Song, W, Lau, SY, et al. Unique reassortant of influenza A(H7N9) virus associated with severe disease emerging in Hong Kong. J Infect 2014;69:6068.
13.Wang, W, Ren, P, Mardi, S, et al. Design of multiplexed detection assays for identification of avian influenza A virus subtypes pathogenic to humans by SmartCycler real-time reverse transcription-PCR. J Clin Microbiol 2009;47:8692.
14.Chan, KH, To, KK, Hung, IF, et al. Differences in antibody responses of individuals with natural infection and those vaccinated against pandemic H1N1 2009 influenza. Clin Vaccine Immunol 2011;18:867873.
15.Ho, PL, Sin, WC, Chan, JF, Cheng, VC, Chan, KH. Severe influenza A H7N9 pneumonia with rapid virological response to intravenous zanamivir. Eur Respir J 2014;44:535537.
16.Liu, B, Havers, F, Chen, E, et al. Risk factors for influenza A(H7N9) disease—China, 2013. Clin Infect Dis 2014;59:787794.
17.Chan, KH, To, KK, Chan, JF, Li, CP, Chen, H, Yuen, KY. Analytical sensitivity of seven point-of-care influenza virus detection tests and two molecular tests for detection of avian origin H7N9 and swine origin H3N2 variant influenza A viruses. J Clin Microbiol 2013;51:31603161.
18.Cheng, VC, Tai, JW, Ho, YY, Chan, JF. Successful control of norovirus outbreak in an infirmary with the use of alcohol-based hand rub. J Hosp Infect 2009;72:370371.
19.Cheng, VC, Wong, LM, Tai, JW, et al. Prevention of nosocomial transmission of norovirus by strategic infection control measures. Infect Control Hosp Epidemiol 2011;32:229237.
20.Cheng, VC, Tai, JW, Chan, WM, et al. Sequential introduction of single room isolation and hand hygiene campaign in the control of methicillin-resistant Staphylococcus aureus in intensive care unit. BMC Infect Dis 2010;10:263.
21.Cheng, VC, Chan, JF, Wong, SC, et al. Proactive infection control measures to prevent nosocomial transmission of carbapenem-resistant Enterobacteriaceae in a non-endemic area. Chin Med J (Engl) 2013;126:45044509.
22.Cheng, VC, Tai, JW, Chen, JH, et al. Proactive infection control measures to prevent nosocomial transmission of vancomycin-resistant enterococci in Hong Kong. J Formos Med Assoc 2014;113:734741.
23.Xu, W, Lu, L, Shen, B, Li, J, Xu, J, Jiang, S. Serological investigation of subclinical influenza A(H7H9) infection among healthcare and non-healthcare workers in Zhejiang Province, China. Clin Infect Dis 2013;57:919921.
24. Centers for Disease Control and Prevention. Interim guidance for infection control within healthcare settings when caring for confirmed cases, probable cases, and cases under investigation for infection with novel tnfluenza A viruses associated with severe disease. http://www.cdc.gov/flu/avianflu/h7n9-infection-control.htm. Accessed June 24, 2014.
25.Buxton Bridges, C, Katz, JM, Seto, WH, et al. Risk of influenza A (H5N1) infection among health care workers exposed to patients with influenza A (H5N1), Hong Kong. J Infect Dis 2000;181:344348.

Metrics

Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed