Avian Influenza: Recent Epidemiology, Travel-Related Risk, and Management
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H5N1 influenza continues to smolder in Southeast Asia over the past 5 years, but the emergence of H7N9 in China in 2012 raised concerns for a new avian influenza threat. In contrast with H5N1 with over 650 confirmed cases over 11 years, H7N9 has infected over 450 persons within 2 years. The case fatality rate for H7N9 (35 %) is lower than for H5N1 (60 %) or H10N8 (67 %) but is comparable to that for the Middle East respiratory syndrome coronavirus (MERS CoV), another emerging zoonosis with travel-associated importations. Exposure to poultry and fomites are considered the likely sources of infection for H7N9, H5N1, and H10N8, with limited human-to-human transmission in close contacts. Most cases have occurred in local populations of affected countries, and travel-related risk can be mitigated by avoiding exposure. Vaccines, antivirals, and other therapeutics remain in development stage or of modest benefit for dangerous infections carrying high morbidity and mortality.
KeywordsAvian influenza H5N1 H7N9 Influenza Travel Therapy Epidemiology Emerging infections Zoonoses
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Conflict of Interest
Poh Lian Lim has no disclosures relevant to this work.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by the authors.
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