The re-emergence of influenza following the COVID-19 pandemic in Victoria, Australia
Catherine GA PendreyJanet StrachanHeidi PeckAmmar AzizJean MoselenRobert MossMd Rezanur RahamanIan BarrKanta SubbaraoSheena G. Sullivan
0
Citation
29
Reference
10
Related Paper
Abstract:
Abstract text Background COVID-19 pandemic mitigation measures, including travel restrictions, effectively limited global circulation of influenza viruses. In Australia, travel bans for non-residents and quarantine requirements for returned travellers were eased in November 2021, providing pathways for influenza viruses to be re-introduced. Methods From 1 November 2021 to 30 April 2022 we conducted an epidemiological study to investigate the re-establishment of influenza in Victoria, Australia. We analyzed case notification data from the Victorian Department of Health to describe case demographics, interviewed the first 200 cases to establish probable routes of virus reintroduction, and examined phylogenetic and antigenic data to understand virus diversity and susceptibility to current vaccines. Results Overall, 1598 notifications and 1064 positive specimens were analyzed. The majority of cases occurred in the 15-34 year age group. Case interviews revealed a higher incidence of international travel exposure during the first month of case detections and high levels of transmission in university residential colleges associated with the return to campus. Influenza A(H3N2) was the dominant subtype, with a single lineage predominating despite multiple importations. Conclusions Enhanced testing for respiratory viruses during the COVID-19 pandemic provided a more complete picture of influenza virus transmission compared to previous seasons. Returned international travellers were important drivers of the re-emergence of influenza, as were young adults, a group whose role has previously been under-recognised in the establishment of seasonal influenza epidemics. Targeting interventions, including vaccination, to these groups could reduce influenza transmission in the future.Keywords:
Pandemic
Demographics
Pandemic
H5N1 genetic structure
Antigenic shift
Cite
Citations (1)
Pandemic
Infectivity
Medical microbiology
H5N1 genetic structure
2019-20 coronavirus outbreak
Cite
Citations (6)
Abstract Avian influenza or “bird flu” is causing increasing concern across the world as experts prepare for the possible occurrence of the next human influenza pandemic. Only influenza A has ever been shown to have the capacity to cause pandemics. Currently A/H5N1, a highly pathogenic avian influenza virus, is of particular concern. Outbreaks of this disease in birds, especially domestic poultry, have been detected across Southeast Asia at regular intervals since 2003, and have now affected parts of Africa and Europe. Many unaffected countries across the world are preparing for the possible arrival of HPAI A/H5N1 in wild birds and poultry within their territories. All such countries need to prepare for the rare possibility of a small number of human cases of HPAI A/H5N1, imported through foreign travel. Although it is by no means certain that HPAI A/H5N1 will be the source of the next pandemic, many countries are also preparing for the inevitable occurrence of human pandemic influenza.
Pandemic
2019-20 coronavirus outbreak
Coronavirus Infections
Cite
Citations (21)
A rapidly spreading, highly pathogenic avian influenza virus A H5N1 in the domestic poultry population has crossed the species barrier to humans and other mammalian species, thus, posing an increasing pandemic threat. The World Health Organization, other agencies, and countries worldwide are closely monitoring the prevalent influenza viruses and their related illnesses to detect any increased virulence or transmissibility that might signal the beginnings of any future pandemic. So far, the H5N1 virus has infected birds in more than 30 countries in Asia, Europe and Africa, while further geographical spread remains likely. Human infections are still rare and the virus does not spread easily from birds to humans or readily from person to person. Although antiviral drugs and vaccination are among the most important measures to be used in case of an influenza pandemic, a timely supply of sufficient quantities will not be possible. This review describes various aspects of avian influenza in birds and in humans; epidemiology, transmission, diagnosis and clinical manifestations. Also presented are the global preparedness, the anti-influenza drugs and vaccines.
Pandemic
Preparedness
Cite
Citations (1)
As the year 2004 progressed, so did conditions favoring the start of an influenza pandemic. The first warning came in January, when Thailand and Vietnam reported fatal human cases of avian influenza caused by the H5N1 strain of influenza A virus. That strain was already notorious for its pandemic potential, revealed during an outbreak in Hong Kong in 1997 and later in a smaller number of human cases in 2003.With the H5N1 strain now endemic in birds in large parts of Asia, the probability that this potential for a pandemic will be realized has increased. Recent laboratory and epidemiologic . . .
Pandemic
Highly pathogenic
Strain (injury)
Influenza pandemic
Cite
Citations (98)
There are many types of influenza viruses, which cause illness in a variety of birds and mammals.New strains are constantly evolving, causing seasonal influenza epidemics in humans.This article provides information about influenza and influenza viruses, and the three influenza pandemics of the twentieth century.Pandemic influenza is differentiated from avian influenza, which is a viral disease that primarily infects birds.The current outbreak of avian influenza H5N1 in poultry flocks across the world is unprecedented in its spread.Human infection with avian influenza is rare and for most strains the symptoms are usually mild.A notable exception is HN51, where almost 60 per cent of the currently recorded 251 human cases have died.While the risk of a pandemic occurring in the current circumstances is unknown, there is a high level of concern worldwide.
Pandemic
Flock
Highly pathogenic
H5N1 genetic structure
Influenza pandemic
Cite
Citations (13)
Emerging viral diseases have become major public health problem in the World. Human-avian influenza is one of emerging viral diseases that significantly contribute to the global burden of respiratory diseases. The objective of this review was to discuss the most recent human-avian influenza outbreak documented in 2021. On basis of their epidemiological features, influenza in humans can be classified as seasonal influenza, pandemic influenza and human-avian influenza. Influenza in humans that are caused by avian influenza viruses which are transmitted across species to humans is known as human-avian influenza. So far, three avian influenza viruses have been recognized to cause human-avian influenza, namely, Asian H7N9 viruses, H5N1 viruses and H5N8. The most recent human-avian influenza outbreak was caused by H5N8, which was documented on February 2021 in Russia. The outbreak was associated with contact with H5N8 infected domestic birds. As the influenza viruses constantly evolve, there is possibility of global outbreak of the disease. Thus, it is necessary to take preparedness actions to counter pandemic threats as they are identified.
Pandemic
H5N1 genetic structure
Preparedness
Highly pathogenic
Cite
Citations (0)
Since 1997 Hong Kong avian influenza virus subtype H5N1 happened first breakthrough the species barrier to infect human beings and caused death,various human avian influenza cases were reported worldwide,degree of concern about human avian influenza has also reached an unprecedented level.Concerning about the possibility that such an influenza virus might become the next influenza pandemic strain,strengthening of the study in human avian influenza is imperative.This review summarizes the current opinions of avian influenza with emphasis on etiology and epidemiology.
Pandemic
Etiology
Human influenza
Highly pathogenic
Influenza pandemic
Cite
Citations (0)
Fowl
Virus isolation
Isolation
Cite
Citations (0)
Since late 2003, avian influenza A/H5N1 virus has infected 100 adults and children in Vietnam, Thailand, Cambodia resulting in 54 deaths (54.0%). The avian H5N1 is becoming more infectious for people and capable of human-to-human transmission. Experts have warned that the widespread occurrence of the H5N1 could ignite a pandemic capable of killing millions of people around the world. However, calculating with any precision the risk or when it will strike is impossible, and yet the consequences of failing to respond to this uncertain threat could be dire. At this stage, time-series epidemiological and virological analysis on the shift of avian to human influenza viruses are quite important for control of the H5N1 outbreak and the pandemic.
Pandemic
Highly pathogenic
Influenza pandemic
Human influenza
Cite
Citations (0)