Five influenza pandemics had occurred during the past century (1918 "Spanish flu" , 1957 "Asian flu" , 1968 "Hong Kong flu" , 1977 "Russian flu" and 2009 H1N1 Pandemic), accounting for hundreds of millions of people infected and tens of millions dead. China was influenced by all the five pandemics, and three of them (1957 "Asian flu" , 1968 "Hong Kong flu" and 1977 "Russian flu" ) were originated from China. The pandemics triggered the establishment of public health agencies and influenza surveillance capacities. In addition, more resources were allocated to influenza-related research, prevention and control. As a leader in the field of influenza, China should further strengthen its pandemic preparedness and response to contribute to global health.
Asian People ; China/epidemiology* ; Disease Outbreaks/history* ; History, 20th Century ; History, 21st Century ; Hong Kong ; Humans ; Influenza A Virus, H1N1 Subtype ; Influenza, Human/history* ; Pandemics/history* ; Public Health

Avian influenza viruses (AIV) have been isolated from a wide range of domestic and wild birds. Wild birds, predominantly ducks, geese and gulls form the reservoir of AIV in nature. The viruses in wild bird populations are a potential source of widespread infections in poultry. Active surveillance for AIV infection provides information regarding AIV distribution, and global AIV surveillance can play a key role in the early recognition of highly pathogenic avian influenza (HPAI). Since 2003 in Korea, there have been four H5N1 HPAI outbreaks caused by clade 2.5, 2.2 and 2.3.2. Therefore, improvement of AIV surveillance strategy is required to detect HPAI viruses effectively. This article deals with the major events establishing the role of wild birds in the natural history of influenza in Korea. We highlighted the need for continuous surveillance in wild birds and characterization of these viruses to understand AIV epidemiology and host ecology in Korea.
Animals ; Birds* ; Charadriiformes ; Disease Outbreaks ; Ducks ; Ecology ; Epidemiology ; Geese ; Influenza in Birds* ; Influenza, Human ; Korea* ; Natural History ; Poultry ; Viruses*

PURPOSE: Natural history and consequences of the novel 2009 influenza A H1N1 (2009 H1N1) infection in immunocompromised pediatric patients are not yet fully understood. In this study, we investigated the clinical features and outcomes of the 2009 H1N1 infection in pediatric patients with hematological and oncological diseases. METHODS: We retrospectively reviewed the medical records of 528 patients who had hematological and oncological diseases and who were treated at 7 referral centers located in the Yeungnam region. Among the 528 patients, 27 with definite diagnosis of 2009 H1N1 infection were the subjects of this study. All patients were divided into the following 3 groups: patients who were receiving chemotherapy (group 1), patients who were immunosuppressed due to a non-malignant hematological disease (group 2), and patients who were off chemotherapy and had undergone their last chemotherapy course within 2 years from the influenza A pandemic (group 3). RESULTS: All 28 episodes of 2009 H1N1 infection were treated with the antiviral agent oseltamivir (Tamiflu(R)), and 20 episodes were treated after hospitalization. Group 1 patients had higher frequencies of lower respiratory tract infection and longer durations of fever and hospitalization as compared to those in group 2. Ultimately, all episodes resolved completely with no complications. CONCLUSION: These results suggest that early antiviral therapy did not influence the morbidity or mortality of pediatric patients with hematological and oncological diseases in the Yeungnam region of Korea after the 2009 H1N1 infection. However, no definite conclusions can be drawn because of the small sample size.
Child ; Fever ; Hematologic Diseases ; Hospitalization ; Humans ; Immunocompromised Host ; Influenza A virus ; Influenza, Human ; Korea ; Medical Records ; Natural History ; Oseltamivir ; Pandemics ; Referral and Consultation ; Respiratory Tract Infections ; Retrospective Studies ; Sample Size

Pandemic influenza has posed an increasing threat to public health worldwide in the last decade. In the 20th century, three human pandemic influenza outbreaks occurred in 1918, 1957 and 1968, causing significant mortality. A number of hypotheses have been proposed for the emergence and development of pandemic viruses, including direct introduction into humans from an avian origin and reassortment between avian and previously circulating human viruses, either directly in humans or via an intermediate mammalian host. However, the evolutionary history of the pandemic viruses has been controversial, largely due to the lack of background genetic information and rigorous phylogenetic analyses. The pandemic that emerged in early April 2009 in North America provides a unique opportunity to investigate its emergence and development both in human and animal aspects. Recent genetic analyses of data accumulated through long-term influenza surveillance provided insights into the emergence of this novel pandemic virus. In this review, we summarise the recent literature that describes the evolutionary pathway of the pandemic viruses. We also discuss the implications of these findings on the early detection and control of future pandemics.
Animals ; Birds ; virology ; Communicable Diseases, Emerging ; epidemiology ; history ; virology ; Evolution, Molecular ; History, 20th Century ; History, 21st Century ; Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; Influenza A Virus, H3N2 Subtype ; genetics ; Influenza in Birds ; epidemiology ; history ; virology ; Influenza, Human ; epidemiology ; history ; virology ; Pandemics ; history

Animals ; History, 20th Century ; History, 21st Century ; Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; isolation & purification ; Influenza, Human ; epidemiology ; history ; virology ; Swine ; virology

Global Health ; History, 20th Century ; Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; isolation & purification ; Influenza A Virus, H3N2 Subtype ; genetics ; isolation & purification ; Influenza, Human ; epidemiology ; history ; therapy ; virology ; Russia ; epidemiology

Global Health ; History, 20th Century ; Humans ; Influenza A Virus, H2N2 Subtype ; genetics ; isolation & purification ; Influenza A Virus, H3N2 Subtype ; genetics ; isolation & purification ; Influenza, Human ; epidemiology ; history ; mortality ; virology

Global Health ; History, 20th Century ; Humans ; Influenza A Virus, H2N2 Subtype ; genetics ; isolation & purification ; Influenza, Human ; epidemiology ; history ; transmission ; virology

Animals ; Global Health ; History, 20th Century ; Humans ; Influenza A virus ; genetics ; isolation & purification ; Influenza, Human ; epidemiology ; history ; mortality ; virology ; Orthomyxoviridae Infections ; epidemiology ; veterinary ; virology ; Swine ; Swine Diseases ; epidemiology ; virology

Animals ; History, 20th Century ; Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; immunology ; isolation & purification ; Influenza, Human ; epidemiology ; history ; immunology ; virology ; Russia ; epidemiology