Influenza a viruses influenza a virus h1n1 subtype. Medical search. Frequent questions

H3N2 Outbreaks Pdm09 H5N1 H1N2 Hemagglutinin Infection Neuraminidase Type of influenza virus Proportion of influenza H9N2 Predominant Endemic in humans Known as swine flu Positive for influenza Pandemic of the 21st ce Illness Antibodies Immunity Detect Influenza C vir Viral Rapid influenza diagnostic tests Reported influenza type Circulate Seasonal and pandemic influenza Vaccination Protein 1918 flu pand Avian influenza viruses Change in the influenza Hong Kong Vaccines Cases of influenza Different influenza Infects Laboratory Strain of influenza Exposure to influenza Characterization Respiratory virus Prevalence Diagnostic Surveillance for influenza Isolates Hydroxyl radicals Effectiveness Detections Epidemiological Swine influenza Epidemic Severe Among influenza Humans Hospitalization Universal influenza Vaccine is available Infect Epidemiology Antigenic drift Virology Strains include Outbreak Diagnosed COVID-19

The known SIV strains include influenza C and the subtypes of influenza A known as H1N1, H1N2, H3N1, H3N2 and H2N3. (wikipedia.org)
Influenza A virus subtypes currently endemic in humans are H3N2 and H1N1 viruses. (cdc.gov)
Examples of different influenza A virus subtypes currently endemic in animals include H1N1 and H3N2 in pigs (different strains than those found in humans), H3N8 in horses, H3N2 in dogs, and H5N1 in wild water birds and domestic poultry. (cdc.gov)
However, in 1998, H3N2 viruses from humans were introduced into the pig population and caused widespread disease among pigs. (cdc.gov)
Several influenza type A(H3N2) viruses also have been isolated in France. (cdc.gov)
Sweden and the Netherlands have reported influenza type A(H3N2) isolation. (cdc.gov)
type A(H3N2) virus has also been isolated from outbreaks in the southeast. (cdc.gov)
Of 17 isolates from sporadic cases, 11 were type A(H1N1), two were type A(H3N2), and four were type B. (cdc.gov)
Type A(H3N2) virus and type A(H1N1) virus have also been reported from a few locations in the United States. (cdc.gov)
however, only H1N1 and H3N2 circulate among humans seasonally. (medscape.com)
62% of all influenza A(H3N2) detections have been reported in adults 65 years of age and older. (canada.ca)
Each year's flu shots contain the scientific community's best estimate of the H1N1, H3N2, and Influenza B strains that will predominate in the coming season. (carnegiecouncil.org)
In sentinel sources, both influenza A subtypes, A(H3N2) and A(H1N1)pdm09, are co-circulating and of the influenza B viruses, the vast majority (97%) are B/Victoria lineage. (flutrackers.com)
Non-structural (NS) 1 proteins from recombinant influenza A/Udorn/72 (H3N2) and influenza A/Finland/554/09 (H1N1pdm09) viruses were purified and used in Western blot analysis to determine specific antibody responses in human sera. (plos.org)
Instead, paired serum samples from patients, who suffered from a laboratory confirmed H1N1pdm09 infection, showed high levels or diagnostic rises (96%) in H1N1pdm virus NS1-specific antibodies and very high cross-reactivity to H3N2 subtype influenza A virus NS1 protein. (plos.org)
The NA genes of H3N2 viruses used for primary infection or vaccination. (wikigenes.org)
Subtypes H1N1, H3N2, and H5N2 were detected. (authorea.com)
Seasonal influenza illness is typically caused by influenza A virus subtypes H1N1 or H3N2, or by influenza B or C viruses. (texas.gov)
While the early start and higher intensity of the 2012/13 influenza A virus (IAV) epidemic was not unprecedented, it was the first IAV epidemic season since the 2009 H1N1 influenza pandemic where the H3N2 subtype predominated. (eurosurveillance.org)
Based on the results of outpatient and hospital surveillance, influenza A(H1N1)pdm09 and A(H3N2) viruses continued to co-circulate in the Region, with very few influenza B detections having been reported during this season. (flutrackers.com)
Of the 1342 influenza A viruses that were subtyped during week 12/2014, 594 (44%) were A(H1N1)pdm09 and 748 (56%) A(H3N2) (Fig. 2a). (flutrackers.com)
Of the 25 143 influenza A viruses that have been subtyped, 14 835 (59%) were A(H1N1)pdm09 and 10 308 (41%) were A(H3N2). (flutrackers.com)
Influenza A(H1N1)pdm09 was the most common strain early in the season, but influenza A(H3N2) predominated later in the season. (health.mil)
Total influenza vaccine effectiveness was low during this season in part because the A(H3N2) strain was antigenically drifted from the vaccine strain. (health.mil)
The 2018-2019 season differed from past seasons in that it was much longer, had a later peak, and the predominant strain of influenza changed from influenza A(H1N1)pdm09 at the beginning of the season to influenza A(H3N2) in the middle of the season. (health.mil)
It was caused by an H3N2 strain of the influenza A virus, descended from H2N2 through antigenic shift, a genetic process in which genes from multiple subtypes reassorted to form a new virus. (searchandrestore.com)
Influenza A(H3N2), the predominant type of influenza virus isolated in the United States during the 1987-88 season, exhibited antigenic drift from previous epidemic strains (1). (searchandrestore.com)
Of the 5861 influenza virus isolates reported to CDC, more than 99% were influenza A. Of the influenza A virus isolates subtyped, 81% were influenza A(H3N2), and 19% were influenza A(H1N1). (cdc.gov)
As of April 10, 179 (99%) of the 180 influenza A(H3N2) viruses characterized at CDC resembled A/Beijing/353/89, the A(H3N2) component included in the 1991-92 influenza vaccine. (cdc.gov)
In Asia, outbreaks of influenza A(H3N2) were reported in Japan, Korea, and the People's Republic of China. (cdc.gov)
In these countries, the proportion of influenza A(H1N1) viruses isolated increased during the latter part of the season as influenza A(H3N2) activity declined. (cdc.gov)
A(H1N2) variant viruses and one human case of infection with an influenza A(H3N2) variant virus were reported officially.3 One additional human case of infection with an influenza A(H1N1)v virus was detected. (who.int)

Major outbreaks of H1N1 strains in humans include the 1918 Spanish flu pandemic, the 1977 Russian flu pandemic and the 2009 swine flu pandemic. (wikipedia.org)
Although it is unusual for people to get influenza A virus infections directly from animals, sporadic human infections and outbreaks caused by certain avian influenza A viruses and swine influenza A viruses have been reported. (cdc.gov)
Type A(H1N1) virus has spread to Italy, Switzerland, United Kingdom, and West Germany, with large outbreaks in some of these countries. (cdc.gov)
However, in Japan, where influenza type B was first isolated in October, influenza type A(H1N1) outbreaks since have occurred among schoolchildren. (cdc.gov)
Earlier this week, the World Health Organization raised its pandemic alert level to 5 (out of 6), indicating widespread human infection of an animal influenza capable of causing community-level outbreaks. (carnegiecouncil.org)
The H5N8 subtype has caused multiple outbreaks in poultry in Europe over the past few winters. (mdpi.com)
Objective To review the effects of school closures on pandemic and seasonal influenza outbreaks. (bmj.com)
This systematic review assesses the effects of school closures on the transmission of influenza, including data from the recent 2009 pandemic as well as from previous pandemics and seasonal outbreaks. (bmj.com)
The available data suggest that school closure can be a useful intervention during influenza outbreaks, with the greatest benefits occurring among school-aged children. (bmj.com)
Hopefully, the knowledge gained in response to the H5N1 and 2009 H1N1 outbreaks, and continued research to more completely understand influenza virus, as well as improvements in vaccine and drug development, will enable us to minimize the effects of future influenza outbreaks. (bcm.edu)
Influenza A virus (IAV) outbreaks constitute a constant threat to public health and pose a remarkable impact on socio-economic systems worldwide. (authorea.com)
RIDTs can be useful to identify influenza virus infection as a cause of respiratory outbreaks in any setting, but especially in institutions (i.e., nursing homes, chronic care facilities, and hospitals), cruise ships, summer camps, schools, etc. (cdc.gov)
Positive RIDT results from one or more ill persons with suspected influenza can support decisions to promptly implement prevention and control measures for influenza outbreaks. (cdc.gov)
Ongoing avian influenza outbreaks in animals pose risk to humans: read the situation analysis and advice to countries from the Food and Agriculture Organization of the United Nations (FAO), the World Health Organization (WHO), and the World Organisation for Animal Health (WOAH). (eurosurveillance.org)
Although influenza A(H1N1) viruses were isolated less frequently worldwide, Belgium and Japan reported that A(H1N1) viruses constituted the majority of isolates and were isolated from outbreaks. (cdc.gov)

Influenza A(H1N1)pdm09 continues to be the most common influenza virus circulating in Canada. (canada.ca)
Among the 10,014 influenza A viruses subtyped, 92% have been A(H1N1)pdm09. (canada.ca)
86% of all influenza A(H1N1)pdm09 detections have been reported in individuals younger than 65 years of age. (canada.ca)
Here, we assessed the induction of protective immunity to these viruses by infection with A(H1N1)pdm09 virus in a newly developed guinea pig model. (eur.nl)
To this end, ten female 12-16 week old strain 2 guinea pigs were inoculated intratracheally with either A(H1N1)pdm09 influenza virus or PBS (unprimed controls) followed 4 weeks later with an A/H7N9 influenza virus challenge. (eur.nl)
R1a-B6-Fc fusions of both isotypes gave complete protection against lethal challenge with both pandemic A/California/07/2009 (H1N1)pdm09 and avian influenza A/Vietnam/1194/2004 (H5N1). (frontiersin.org)

The current H5N1 bird flu, also an Influenza A virus, has a similar effect. (wikipedia.org)
Epstein SL , Tumpey TM , Misplon JA , Lo CY , Cooper LA , Subbarao K , DNA vaccine expressing conserved influenza virus proteins protective against H5N1 challenge infection in mice. (cdc.gov)
More recently, H5N1 viruses from birds have caused sporadic infections in wild foxes in the U.S. and in other countries. (cdc.gov)
The fact that the H1N1 candidate vaccine was effective against H5N1 infection - a different influenza subtype - suggests the antibodies the vaccine induces can be protective against other "group 1" influenza subtypes, including H1 and H5. (medscape.com)
This paper, and the accompanying Diagram, describe many aspects of the influenza vaccine process including important similarities and differences in how seasonal human influenza viruses and H5N1 viruses are handled. (who.int)
Before 2004, GISN primarily focused on seasonal influenza viruses for vaccine development but since 2004, has expanded its scope to include H5N1 viruses because this virus constitutes an unusually serious pandemic risk. (who.int)
Therefore, WHO now reviews the available antigenic and genetic data on animal and human H5N1 viruses in addition to the analyses of seasonal vaccine stains and has developed and made H5N1 candidate vaccine viruses available to vaccine producers so they can work on developing safe and effective human H5N1 vaccines for potential productioni. (who.int)
Some of these H5N1 candidate vaccine viruses have been used by manufacturers to produce human influenza H5N1 vaccines, some of which have been tested in clinical trials. (who.int)
Research describing two mutant strains of H5N1 avian influenza that spread between mammals is likely to be published in its entirety. (scientificamerican.com)
Two teams of scientists, led by Ron Fouchier of Erasmus Medical Center in Rotterdam, the Netherlands, and Yoshihiro Kawaoka of the University of Wisconsin-Madison, have created mutant strains of H5N1 avian influenza. (scientificamerican.com)
The subtype behind the 2009 'swine flu' pandemic is H1N1, which has the same version of neuraminidase as H5N1, but a different version of hemagglutinin. (scientificamerican.com)
One particular strain of H5N1, called highly pathogenic avian influenza (HPAI), is responsible for the 'bird flu' scares. (scientificamerican.com)
Wild H5N1 viruses cannot latch on tothe cells in a person's nose and throat, but the mutant strains created by Fouchier and Kawaoka can spread between ferrets, which are viewed as a good animal model of flu transmission between humans. (scientificamerican.com)
Kawaoka and his team, whose work has been accepted by Nature, created a chimeric virus with the hemagglutinin protein from H5N1 and the genes from the 2009 pandemic strain of H1N1. (scientificamerican.com)
Kawaoka notes that H5N1 viruses already circulate in nature, mutate constantly and could cause pandemics. (scientificamerican.com)
More practically, the research could allow public-health workers to monitor wild viruses for similar mutations that make H5N1 more dangerous to humans. (scientificamerican.com)
Unlike the avian H5N1 flu, the H1N1 swine flu is capable of being transmitted easily from person to person. (bcm.edu)
Fortunately, however, H1N1 is far less deadly than the H5N1 virus. (bcm.edu)
Disease relevance of na Although differing in their surface hemagglutinin and neuraminidase components, a notable feature of these H9N2 viruses is that the six genes encoding the internal components of the virus are similar to those of the 1997 H5N1 human and avian isolates. (wikigenes.org)
We have previously described R1a-B6, an alpaca-derived single domain antibody (nanobody), that is capable of potent cross-subtype neutralization in vitro of H1N1, H5N1, H2N2, and H9N2 influenza viruses, through binding to a highly conserved epitope in the influenza hemagglutinin stem region. (frontiersin.org)
The antibodies also blocked other flu subtypes, including H5N1. (nih.gov)

It is an orthomyxovirus that contains the glycoproteins hemagglutinin (H) and neuraminidase (N), antigens whose subtypes are used to classify the strains of the virus as H1N1, H1N2 etc. (wikipedia.org)
So, for example, a virus with version 1 of the HA protein and version 2 of the NA protein would be called influenza A subtype H1N2 (A H1N2, for short). (bcm.edu)
For this reason, they are described as H1N1, H1N2 etc. depending on the type of H or N antigens they express with metabolic synergy. (indiatimes.com)

Hemagglutinin causes red blood cells to clump together and binds the virus to the infected cell. (wikipedia.org)
The resulting new virus might then be able to infect humans and spread easily from person to person, but it could have surface proteins (hemagglutinin and/or neuraminidase) different than those currently found in influenza viruses that routinely circulate in humans-this could make it seem like a "new" influenza virus to people, one that had not been encountered before. (cdc.gov)
The genetic information in these viruses could reassort to create a new influenza A virus with a hemagglutinin and/or neuraminidase gene from the avian virus and other genes from the human virus. (cdc.gov)
Influenza A viruses with a hemagglutinin against which humans have little or no immunity that have reassorted with a human influenza virus are more likely to result in sustained human-to-human transmission and have pandemic potential. (cdc.gov)
It displays part of hemagglutinin (HA), an influenza protein, on the surface of a microscopic nanoparticle made of nonhuman ferritin. (medscape.com)
Unfortunately, influenza vaccine composition needs to be updated annually due to antigenic shift and drift in the viral immunogen hemagglutinin (HA). (mdpi.com)
The letters H and N stand for hemagglutinin and neuraminidase, two kinds of protein on the surface of the influenza virus. (carnegiecouncil.org)
For example, H1N1 has a coat of the first subtype of hemagglutinin and the first subtype of neuraminidase. (carnegiecouncil.org)
Hemagglutinin helps a virus attach to and insert itself into a target cell, while neuraminidase is what helps the viruses break back out and spread to other cells. (carnegiecouncil.org)
These viruses are classified according to the identity of two of their surface proteins--hemagglutinin (H5 in this subtype) and neuraminidase (N1). (scientificamerican.com)
High impact information on NA This was indicated by the ability of viruses bearing the H2- hemagglutinin glycoprotein, regardless of its associated neuraminidase, to induce lymphocyte proliferation in normal spleen cell suspensions and by the ability of antisera with specificity for the H2- hemagglutinin. (wikigenes.org)
Phylogenetic analysis of influenza viruses isolated from wild ducks of the Lerma marshes revealed that hemagglutinin (HA) gene sequences were related to waterfowl, swine, and poultry IAV strains previously isolated in the United States and Mexico. (authorea.com)

People with close or prolonged unprotected contact (not wearing respiratory and eye protection) with infected birds or places that sick birds or their mucous, saliva, or feces have contaminated, might be at greater risk of bird flu virus infection. (cdc.gov)
Seasonal Influenza is an acute viral infection that spreads easily from person to person and seasonal epidemics usually occur at this time. (thestkittsnevisobserver.com)
Vaccination is the primary intervention used to curb influenza virus infection, and the WHO recommends immunization for at-risk individuals to mitigate disease. (mdpi.com)
We discuss the different vectored vaccines that have been or are currently in clinical trials, with a forward-looking focus on immunogens that may be protective against seasonal and pandemic influenza infection, in the context of viral-vectored vaccines. (mdpi.com)
Influenza infection poses a significant public health threat. (atlantis-press.com)
Influenza virus subtypes co-circulate with no reports of co-infection. (atlantis-press.com)
Based on quantitative Western blot analysis, only two of the 45 (4.4%) Pandemrix-vaccinated narcoleptic patients showed specific antibody response against the NS1 protein from the H1N1pdm09 virus, indicating past infection with the H1N1pdm09 virus. (plos.org)
Based on our findings, it is unlikely that H1N1pdm09 virus infection contributed to a sudden increase in the incidence of childhood narcolepsy observed in Finland in 2010 after AS03-adjuvanted Pandemrix vaccination. (plos.org)
It is always a great concern when a new flu virus emerges, because the general population does not have immunity and almost everyone is susceptible to infection and disease. (bcm.edu)
The Verigene Respiratory Virus Plus Nucleic Acid Test (RV+) on the Verigene System is a qualitative nucleic acid multiplex test intended to simultaneously detect and identify multiple respiratory virus nucleic acids in nasopharyngeal (NP) swab specimens from individuals with signs and symptoms of respiratory tract infection. (fda.gov)
Negative results for Influenza A, Influenza B, or RSV do not preclude influenza virus or RSV infection and should not be used as the sole basis for diagnosis, treatment, or patient management decisions. (fda.gov)
Conversely, positive results do not rule-out bacterial infection or co-infection with other viruses. (fda.gov)
If infection with a novel Influenza A virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions used specifically for novel virulent influenza viruses and sent to state or local health department for testing. (fda.gov)
By day 7, only viral antigen positive cells were found after H7N9 virus infection in the nasal turbinates and the lungs of unprimed controls. (eur.nl)
Thus infection with H1N1pdm09 virus induced partially protective heterosubtypic immunity to H7N9 virus in (isogenic) guinea pigs that could not be attributed to cross-reactive virus neutralizing antibodies. (eur.nl)
He said that the biology and epidemiology of the virus itself makes infection extremely difficult to detect in its early stages, because the majority of cases show no symptoms for five days or longer after exposure. (ucla.edu)
However, RIDTs have limited sensitivity to detect influenza virus infection and negative test results should be interpreted with caution given the potential for false negative results. (cdc.gov)
Some RIDTs distinguish between influenza A or B virus infection while others do not. (cdc.gov)
However, due to th e limited sensitivities and predictive values of RIDTs, negative results of RIDTs do not exclude influenza virus infection in patients with signs and symptoms suggestive of influenza. (cdc.gov)
However, negative RIDT results do not exclude influenza virus infection as a cause of a respiratory outbreak because of the limited sensitivity of these tests. (cdc.gov)
Testing respiratory specimens from several persons with suspected influenza will increase the likelihood of detecting influenza virus infection if influenza virus is the cause of the outbreak. (cdc.gov)
Clinical signs and symptoms consistent with influenza o Having clinical signs and symptoms consistent with influenza increases the pre-test probability of influenza virus infection, which increases the reliability of a positive RIDT result. (cdc.gov)
Our findings demonstrate AAV delivery of cross-subtype neutralizing nanobodies may be an effective strategy to prevent influenza infection and provide long-term protection independent of a host induced immune response. (frontiersin.org)
Clinical consultation rates for influenza-like illness (ILI) and/or acute respiratory infection (ARI) returned to pre-season or below baseline levels in most of the countries in the WHO European Region. (flutrackers.com)
Since the last risk assessment on 21 May 2021, one new laboratory-confirmed human case of influenza A(H5N6) virus infection was reported from China to WHO on 30 May 2021. (who.int)
1. What is the likelihood that additional human cases of infection with avian influenza A(H5) viruses will occur? (who.int)

Neuraminidase is a type of glycoside hydrolase enzyme which helps to move the virus particles through the infected cell and assist in budding from the host cells. (wikipedia.org)
H1 describes the virus's HA subtype and N1 describes the neuraminidase subtype. (medscape.com)
Neuraminidase, or NA, is another influenza surface protein. (medscape.com)
Disease relevance of NA Structure of the neuraminidase gene in human influenza virus A/ PR/ 8/ 34. (wikigenes.org)
Disease relevance of NA The complete nucleotide sequence of the neuraminidase gene of influenza. (wikigenes.org)

RIDTs that provide results on type of influenza virus (e.g. influenza A or B virus), do not provide information on influenza A virus subtype (e.g. (cdc.gov)

Influenza B accounted for a small proportion of influenza detections, which remained steady over the past weeks. (flutrackers.com)

Pigs can also become infected with the H4N6 and H9N2 subtypes. (wikipedia.org)

The effectiveness of the influenza vaccine for the 2018-19 season is estimated to be 72% against the predominant circulating strain this season, with significant protection observed in all age groups. (canada.ca)
Influenza peaks were observed in October each season, with variant predominant strains. (atlantis-press.com)
Performance characteristics for Influenza A Virus were established when Influenza A/H3, A/H1, and 2009 H1N1 were the predominant Influenza A viruses circulating. (fda.gov)

Some strains of H1N1 are endemic in humans and cause a small fraction of all influenza-like illness and a small fraction of all seasonal influenza, for instance in 2004-2005. (wikipedia.org)

Swine influenza (also known as swine flu or pig flu) is a respiratory disease that occurs in pigs that is caused by the Influenza A virus. (wikipedia.org)
So what, exactly, is Influenza virus A subtype H1N1, commonly known as swine flu? (carnegiecouncil.org)

This is consistent with the decline in the percentage of ILI and ARI sentinel specimens testing positive for influenza. (flutrackers.com)
Environmental samples from these stalls tested positive for influenza A(H5N6) viruses. (who.int)

As a result of the rapid, global spread of H1N1, the first pandemic of the 21st century was declared in June of 2009. (bcm.edu)

In 1976, a novel swine influenza A (H1N1) caused severe respiratory illness in 13 soldiers, with one death at Fort Dix, New Jersey. (wikipedia.org)
Influenza A viruses that typically are endemic in one animal species sometimes can cause illness in another species. (cdc.gov)
If this new influenza A virus causes illness in people and is transmitted easily from person to person in a sustained manner, an influenza pandemic can occur. (cdc.gov)
Influenza viruses also can cause pandemics, during which rates of illness and death from influenza-related complications can increase worldwide. (cdc.gov)
Vaccination is associated with reductions in influenza-related respiratory illness and physician visits among all age groups, hospitalization and death among persons at high risk, otitis media among children, and work absenteeism among adults ( 8--18 ). (cdc.gov)
Influenza viruses with reduced in vitro sensitivity have been shown to be transmissible and to cause typical influenza illness. (nih.gov)
Flu, or influenza, is a contagious respiratory illness that spreads from person to person through the air via coughs or sneezes or through contact with infected surfaces. (bcm.edu)
Influenza ("the flu") is a respiratory illness caused by the influenza virus. (texas.gov)
An influenza-associated pediatric death is a death in a child under 18 years of age resulting from a clinically compatible illness that is confirmed to be influenza by an appropriate laboratory or rapid diagnostic test. (texas.gov)
Most people who develop influenza illness will recover on their own with bed rest and do not need medication. (texas.gov)
These medications are usually prescribed to persons who have a severe illness or to those who are at higher risk for developing serious illness or complications due to influenza. (texas.gov)
Some people are more likely to develop complications from their influenza illness, leading to hospitalization or even death. (texas.gov)
Time from illness onset to collection of respiratory specimens for testing o Testing specimens collected within 48-72 hours of illness onset (when influenza viral shedding is highest) is more likely to yield positive RIDT results. (cdc.gov)

Transmission of the virus from pigs to humans is not common and does not always lead to human influenza, often resulting only in the production of antibodies in the blood. (wikipedia.org)
Zharikova D , Mozdzanowska K , Feng J , Zhang M , Gerhard W . Influenza type A virus escape mutants emerge in vivo in the presence of antibodies to the ectodomain of matrix protein 2. (cdc.gov)
Cross-subtype neutralizing single domain antibodies against influenza present new opportunities for immunoprophylaxis and pandemic preparedness. (frontiersin.org)
A much more promising strategy is to use recombinant monoclonal antibodies (mAbs) against influenza and several are currently in clinical development ( 9 - 13 ). (frontiersin.org)
Animals given both the DNA and the boost vaccines produced antibodies that blocked several H1N1 strains. (nih.gov)

Modified M2 proteins produce heterotypic immunity against influenza A virus. (cdc.gov)
Okuda K , Ihata A , Watabe S , Okada E , Yamakawa T , Hamajima K , Protective immunity against influenza A virus induced by immunization with DNA plasmid containing influenza M gene. (cdc.gov)
When shifts happen, most people have little or no immunity against the new virus. (cdc.gov)
Epidemiology and Animal Health Economics category, oral -Matthew Allerson, University of Minnesota, for "The impact of maternally derived immunity on influenza virus transmission in neonatal pig populations," and Heidi Pecoraro, Colorado State University, for "Comparison of virus isolation, one-step real-time reverse transcriptase-PCR assay, and two rapid influenza diagnostic tests for detecting canine influenza virus (H3N8) shedding in dogs. (avma.org)
Heterosubtypic immunity is defined as immune-mediated (partial) protection against an influenza virus induced by an influenza virus of another subtype to which the host has not previously been exposed. (eur.nl)
In a pandemic, a new influenza virus emerges and infects the human population which has little or no pre-existing immunity ( 2 , 3 ). (frontiersin.org)

The following virus types and subtypes are identified using the RV+: Influenza A, Influenza A subtype H1, Influenza A subtype H3, 2009 H1N1, Influenza B, Respiratory Syncytial Virus (RSV) subtype A, and RSV subtype B. The test is not intended to detect Influenza C virus. (fda.gov)

The 1918 flu was an unusually severe and deadly strain of H1N1 avian influenza, a viral infectious disease, that killed from 17 to 50 or more million people worldwide over about a year in 1918 and 1920. (wikipedia.org)
Ulmer JB , Donnelly JJ , Parker SE , Rhodes GH , Felgner PL , Dwarki VJ , Heterologous protection against influenza by injection of DNA encoding a viral protein. (cdc.gov)
WHO Collaborating Center for Influenza, Epidemiology Office and Influenza Br, Div of Viral Diseases, Center for Infectious Diseases, CDC. (cdc.gov)
Please note that questions are limited to clinicians who would like information on CDC's current influenza recommendations for vaccination and anti-viral medications. (cdc.gov)
At the conclusion of today's session the participant will be able to describe the current status of influenza activity in the United States, discuss the circulating influenza strains seen this season and the implications for clinicians, discuss the use of influenza diagnostic tests and the role in clinical care and discuss anti-viral treatment implications for patients evaluation treatment and testing. (cdc.gov)
Her research includes studies on influenza vaccine effectiveness and preventing hospitalization, the use of influenza anti-viral medications in outpatient settings, and the impact of seasonal influenza on children with neurologic disorders. (cdc.gov)
Her current primary research focuses on influenza anti-viral treatment as well as influenza vaccine effectiveness. (cdc.gov)
Rapid influenza diagnostic tests (RIDTs) are immunoassays that can identify the presence of influenza A and B viral nucleoprotein antigens in respiratory specimens, and display the result in a qualitative way (positive vs. negative) (1). (cdc.gov)
Rapid molecular assays are a new type of influenza diagnostic test that use isothermal nucleic acid amplification for viral detection. (cdc.gov)
A universal flu vaccine would block many viral strains for years and greatly control the spread of influenza. (nih.gov)

Testing Methods" and "Table 2: Characteristics of Rapid Influenza Diagnostic Tests" . (cdc.gov)

Finland has reported influenza type A virus of unknown subtype. (cdc.gov)
Type A viruses have dominated across the European Region, although a number of countries reported influenza type B virus dominance or co-dominance of types A and B viruses. (flutrackers.com)

Influenza activity in Canada is declining but influenza continues to circulate with eastern regions continuing to report higher levels of influenza activity compared to western regions. (canada.ca)
Human infections with viruses of animal origin are expected at the human-animal interface wherever these viruses circulate in animals. (who.int)

4 Here, we review epidemiological studies to assess the effects of school closures on transmission and incidence of seasonal and pandemic influenza, updating and extending previous reviews 2 , 4 to include data from the 2009 pandemic. (bmj.com)

Epstein SL , Stack A , Misplon JA , Lo CY , Mostowski H , Bennink J , Vaccination with DNA encoding internal proteins of influenza virus does not require CD8(+) cytotoxic T lymphocytes: either CD4(+) or CD8(+) T cells can promote survival and recovery after challenge. (cdc.gov)
Protection of mice against influenza A virus challenge by vaccination with baculovirus-expressed M2 protein. (cdc.gov)
and 5) the assessment of vaccine supply, timing of influenza vaccination, and prioritization of inactivated vaccine in shortage situations. (cdc.gov)
Influenza vaccination is the primary method for preventing influenza and its severe complications. (cdc.gov)
RÉSUMÉ Les informations sur la prévalence de la grippe, les sous-types circulants du virus et la saisonnalité sont essentielles pour la sélection des souches destinées aux vaccins annuels, ainsi que pour la planification des programmes de vaccination. (who.int)
A sudden increase in the incidence of childhood narcolepsy was observed after vaccination with AS03-adjuvanted Pandemrix influenza vaccine in Finland at the beginning of 2010. (plos.org)
Here, we analysed whether the coinciding influenza A H1N1pdm pandemic contributed, together with the Pandemrix vaccination, to the increased incidence of childhood narcolepsy in 2010. (plos.org)
An H1N1 (swine flu) outbreak among recruits at Fort Dix leads to a vaccination program to prevent a pandemic. (searchandrestore.com)
The most important strategy for preventing influenza-associated morbidity and mortality is vaccination of persons in high-risk groups with vaccine closely matched to circulating strains. (cdc.gov)

Influenza A virus M2 protein: monoclonal antibody restriction of virus growth and detection of M2 in virions. (cdc.gov)
Neirynck S , Deroo T , Saelens X , Vanlandschoot P , Jou WM , Fiers W . A universal influenza A vaccine based on the extracellular domain of the M2 protein. (cdc.gov)
Mozdzanowska K , Feng J , Eid M , Kragol G , Cudic M , Otvos JL , Induction of influenza type A virus-specific resistance by immunization of mice with a synthetic multiple antigenic peptide vaccine that contains ectodomains of matrix protein 2. (cdc.gov)
Sequence comparison between the extracellular domain of M2 protein human and avian influenza A virus provides new information for bivalent influenza vaccine design. (cdc.gov)
Hydroxyl radicals inside nanoe™ X particles draw out hydrogen from the virus' protein envelope. (panasonic.com)
The numbers refer to protein subtypes-small variations in structure. (carnegiecouncil.org)
The analysis was based on the presence or absence of antibody response against non-structural protein 1 (NS1) from H1N1pdm09 virus, which was not a component of Pandemrix vaccine. (plos.org)
All human infections caused by a new influenza subtype are required to be reported under the International Health Regulations (IHR, 2005).4 This includes any influenza A virus that has demonstrated the capacity to infect a human and its haemagglutinin gene (or protein) is not a mutated form of those, i.e. (who.int)

Genetic analysis of virus from tissue preserved medically or in permafrost suggests that seasonal H1N1 strains of today descend from the 1918 flu pandemic virus, but the result is not conclusive. (wikipedia.org)

While a "shift" of this kind has not occurred in relation to avian influenza viruses, such a "shift" occurred in the spring of 2009 when an H1N1 virus with genes from North American Swine, Eurasian Swine, humans and birds emerged to infect people and quickly spread, causing a pandemic. (cdc.gov)

This type of major change in the influenza A viruses is known as " antigenic shift . (cdc.gov)

Influenza B was also isolated in Hong Kong and Singapore in September and October. (cdc.gov)
The outbreak, which is sometimes called the Hong Kong flu of 1968, was the third influenza pandemic of the 20th century. (searchandrestore.com)
Hong Kong flu was one of the famous influenza pandemics in history. (searchandrestore.com)

Fan J , Liang X , Horton MS , Perry HC , Citron MP , Heidecker GJ , Preclinical study of influenza virus A M2 peptide conjugate vaccines in mice, ferrets, and rhesus monkeys. (cdc.gov)
Among all vaccines, however, the process of making influenza vaccines is considered uniquely complicated and difficult. (who.int)
Since 1971, WHO has provided formal recommendations for the composition of seasonal influenza vaccines based on the information provided by the GISN. (who.int)
Since the development and production of influenza vaccines requires several months, these recommendations precede the period of anticipated use by up to eight months. (who.int)
The results of that data examination in turn allow these experts to select candidate vaccine viruses that might be included -- if they pass additional testing -- in the following season's vaccines. (who.int)
ABSTRACT Information on the prevalence of influenza, circulating virus subtypes and seasonality is essential for selecting strains for annual vaccines and for planning immunization programmes. (who.int)
In addition, the lineage of 169 influenza B viruses has been determined: 155 (92%) belonged to the B/Yamagata lineage (the lineage of the B virus recommended by WHO for inclusion in trivalent seasonal influenza vaccines) and 14 (8%) to the B/Victoria lineage. (flutrackers.com)
The data and findings in this report reinforce the importance of the use of up-to-date multivalent influenza vaccines that protect against several different specific virus strains that may become common in the coming influenza season. (health.mil)

Since the start of the year we have received laboratory confirmation for approximately three (3) cases of Influenza A (H1N1). (thestkittsnevisobserver.com)

The vaccine stimulates protective immune responses against very different influenza subtypes by homing in on an area of the virus that remains relatively constant from strain to strain. (medscape.com)
In the spring of 2009, a different influenza virus - one that had never been seen before - suddenly appeared. (bcm.edu)

Antigenic shift results when a new influenza A virus subtype against which most people have little or no immune protection infects humans. (cdc.gov)
Influenza infects an estimated 8% of the U.S. population annually, with children and the elderly at highest risk. (health.mil)

Panasonic's nanoe™ X technology has also been found to inhibit more than 99.9%* of certain viruses during laboratory testing. (panasonic.com)
A total 2,002 laboratory detections of influenza were reported, of which 98% were influenza A. (canada.ca)
Medical records and surveillance database of laboratory-confirmed influenza cases were reviewed from October 2015 to 2019. (atlantis-press.com)
This study included a total of 1928 patients with laboratory-confirmed influenza infections. (atlantis-press.com)
These laboratory strains could be passed between mammals more easily than wild strains of the virus. (scientificamerican.com)
Public health authorities should be notified of any suspected institutional outbreak and respiratory specimens should be collected from ill persons (whether positive or negative by RIDT) and sent to a public health laboratory for more accurate influenza testing. (cdc.gov)
The Armed Forces Health Surveillance Branch of the Defense Health Agency utilizes electronic sources of ambulatory medical encounters, hospitalizations, and laboratory data to conduct annual influenza surveillance among all Department of Defense (DOD) beneficiaries across the world. (health.mil)

This significant advance lays the groundwork for the development of a vaccine to provide long-lasting protection against any strain of influenza," says Dr. Anthony S. Fauci, director of NIH's National Institute of Allergy and Infectious Diseases. (nih.gov)

A team that included some of the same UCLA and Arizona scientists reported in 2016 that exposure to influenza viruses during childhood gives people partial protection for the rest of their lives against distantly related influenza viruses. (ucla.edu)
1 Service members may also be at a higher risk for exposure to influenza because of increased crowding and mixing in the recruit setting and duty assignments abroad where influenza subtypes may differ. (health.mil)

Together, this network processes an estimated 150,000 to 200,000 respiratory specimens per year with approximately 5000 viruses voluntarily shared by the NICs undergoing extensive antigenic and genetic characterization among the WHO CCs. (who.int)
Further characterization of the virus from the patient is planned. (who.int)

Findings for each respiratory virus type are presented individually and combined for all three as a percent of total emergency department visits. (cdc.gov)
For more detailed weekly and cumulative influenza data, see the text descriptions for Figures 2 and 3 or the Respiratory Virus Detections in Canada Report . (canada.ca)

The EuroFlu bulletin describes and comments on influenza activity in the 53 Member States in the WHO European Region to provide information to public health specialists, clinicians and the public on the timing of the influenza season, the spread of influenza, the prevalence and characteristics of circulating viruses (type, subtype and lineage) and severity. (flutrackers.com)

Diagnostic codes and clinical terms were used to create definitions for diagnosed COVID-19, influenza, and RSV. (cdc.gov)
The information provided by GISN through its participating institutions has identified new influenza threats, substantially helped define the epidemiology of influenza and the molecular evolution of the viruses, and formed the basis for selecting new influenza vaccine strains and for updating diagnostic tests. (who.int)

This report summarizes surveillance for influenza in the United States and worldwide during the 1991-92 season and describes the composition of the 1992-93 influenza vaccine. (cdc.gov)

Canada reported the first isolates of the 1988-89 influenza season from type A(H1N1) virus activity in late November and early December. (cdc.gov)
Amantadine inhibits the replication of influenza A virus isolates from each of the subtypes, i.e. (nih.gov)
It has very little or no activity against influenza B virus isolates. (nih.gov)
Sensitivity test results, expressed as the concentration of amantadine required to inhibit by 50% the growth of virus (ED 50 ) in tissue culture vary greatly (from 0.1 mcg/mL to 25 mcg/mL) depending upon the assay protocol used, size of virus inoculum, isolates of influenza A virus strains tested, and the cell type used. (nih.gov)
Influenza A(H1N1) viruses were isolated most frequently in the mid-Atlantic and South Atlantic regions and accounted for 30% and 52% of influenza A isolates, respectively. (cdc.gov)

nanoe™ X technology draws on the power of hydroxyl radicals to effectively inhibit adhered and airborne viruses, pollutants and odours. (panasonic.com)
Certain virus is inhibited, transforming the hydroxyl radicals into stable water molecules. (panasonic.com)

Molecular surveillance of the influenza viruses should be enhanced continuously for a better understanding of the influenza activity and assessment of vaccine effectiveness. (atlantis-press.com)
Although antiviral drugs such as Oseltamivir are available to control the spread of the virus their effectiveness is limited in treating patients with influenza ( 5 , 6 ). (frontiersin.org)

Fewer influenza B detections have been reported this season compared to recent seasons at this time of year. (canada.ca)
The majority of reported influenza virus detections across the Region were type A, although 5 countries reported type B virus dominance and 2 reported co-dominance of type A and B viruses. (flutrackers.com)
Since week 40/2013, sentinel and non-sentinel sources have yielded 37 583 influenza detections: 35 897 (95%) were influenza A and 1686 (5%) influenza B viruses (Fig. 2b). (flutrackers.com)

Even though small clusters of A(H5) virus infections have been reported previously including those involving healthcare workers, current epidemiological and virological evidence suggests that influenza A(H5) viruses have not acquired the ability of sustained transmission among humans, thus the likelihood is low. (who.int)

Other strains of H1N1 are endemic in pigs (swine influenza) and in birds (avian influenza). (wikipedia.org)
Influenza viruses that are normally found in swine are known as swine influenza viruses (SIVs). (wikipedia.org)
Swine influenza virus is common throughout pig populations worldwide. (wikipedia.org)
In the 2009 flu pandemic, the virus isolated from patients in the United States was found to be made up of genetic elements from four different flu viruses - North American swine influenza, North American avian influenza, human influenza, and swine influenza virus typically found in Asia and Europe - "an unusually mongrelised mix of genetic sequences. (wikipedia.org)
If swine influenza spreads, prescriptions for Tamiflu may outstrip supplies. (carnegiecouncil.org)

In France, an influenza type A(H1N1) epidemic has been reported. (cdc.gov)
Dr. Havers completed the epidemic intelligence service training in the influenza division at CDC and is board certified to practice internal medicine and infectious diseases. (cdc.gov)
Influenza A variants with reduced in vitro sensitivity to amantadine have been isolated from epidemic strains in areas where adamantane derivatives are being used. (nih.gov)
Influenza B viruses, which caused a major epidemic in the United States in 1979-1980 and low-level morbidity last winter, have been detected in all regions of the world. (searchandrestore.com)

Influenza A (H1N1) virus has been associated with severe diseases and complications in neighbouring Caribbean territories. (thestkittsnevisobserver.com)
Continued weekly surveillance of influenza among DOD populations is crucial to track increases in activity each season and the potential emergence of new and/or severe influenza subtypes. (health.mil)

The NIH's National Institute of Allergy and Infectious Diseases (NIAID) hopes to develop a vaccine that will overcome the challenges associated with seasonal changes among influenza strains. (medscape.com)
Nevertheless, the antigenic drift through several mechanisms that include insertions, deletions, and substitutions are frequent among influenza A and different lineages of influenza B viruses [ 7 - 10 ]. (atlantis-press.com)

Influenza A viruses are endemic (can infect and regularly transmit) in 6 animal species or groups (wild waterfowl, domestic poultry, swine, horses, dogs, and bats) in addition to humans. (cdc.gov)
Therefore, careful evaluation of influenza A viruses recovered from humans and animals that are infected with avian influenza A viruses is important to identify genetic reassortment if it occurs. (cdc.gov)
Highly pathogenic influenza A virus H5 subtype remains a risk for transmission in humans. (mdpi.com)
So far, little is known about how this virus evolves and adapts to infect humans. (mdpi.com)
It is a subtype of the influenza A virus--the most virulent of the influenza viruses to affect humans. (scientificamerican.com)
There are three different types of influenza virus - A, B, and C. Type A viruses infect humans and several types of animals, including birds, pigs, and horses. (bcm.edu)
Type B influenza is normally found only in humans, and type C is mostly found in humans, but has also been found in pigs and dogs. (bcm.edu)
In conclusion, the co-circulation of three IAV subtypes in wild ducks close to backyard farms in Mexico, as well as, the local identification of HA gene sequences genetically related to Mexican livestock IAV strains and also to North American waterfowl IAV strains, highlight the importance of the Lerma marshes for influenza surveillance given the close interaction among wild birds, poultry, pigs, and humans. (authorea.com)

Ambulatory data for influenza-like illnesses (ILIs), influenza hospitalization data, and lab data for influenza-confirmed cases were used for the surveillance. (health.mil)

Researchers are conducting the first-in-human trial of a universal influenza vaccine candidate, the National Institutes of Health (NIH) announced April 3. (medscape.com)
This phase 1 clinical trial is a step forward in our efforts to develop a durable and broadly protective universal influenza vaccine. (medscape.com)
A team of VRC scientists developed the universal influenza vaccine prototype. (medscape.com)

The Influenza vaccine is available at all health centers in the Federation of St. Kitts and Nevis. (thestkittsnevisobserver.com)
A new influenza vaccine is available each year, typically beginning in August or September. (texas.gov)

The segmented genome allows influenza A viruses from different species to mix genes (reassortment) and create a new virus if influenza A viruses from two different species infect the same person or animal at the same time. (cdc.gov)
After 10 rounds, the virus could spread through the air to infect ferrets in neighboring cages. (scientificamerican.com)
Most healthy adults who are ill with influenza may be able to infect other people beginning 1 day before symptoms develop and up to 5 to 7 days after becoming sick. (texas.gov)

While at CDC Dr. Havers research interests have focused on the epidemiology, prevention, and treatment of influenza. (cdc.gov)

viruses, an arrest of significant evolution of the NA discordant with the continuing antigenic drift of HA was found in the 1980- 1983 period. (wikigenes.org)
2 Each influenza season is different because of antigenic drift in the circulating influenza subtypes, the degree of match between vaccine subtypes and circulating subtypes, and vaccine coverage of the population. (health.mil)

In virology, influenza A virus subtype H1N1 (A/H1N1) is a subtype of influenza A virus. (wikipedia.org)

The influenza A subtypes are further classified into strains, and the names of the virus strains include the place where the strain was first found and the year of discovery. (bcm.edu)

However, an island-wide outbreak of influenza A(H1N1) virus occurred in Trinidad during September, and one isolate of influenza type B was also recovered. (cdc.gov)
Study selection Studies were included if they reported on a seasonal or pandemic influenza outbreak coinciding with a planned or unplanned school closure. (bmj.com)
Every few decades or so, a new version of the influenza virus emerges in the human population that causes a serious global outbreak of disease called a pandemic . (bcm.edu)
Influenza A (H1N1) virus is the subtype of influenza A virus that was the most common cause of human influenza (flu) in 2009, and is associated with the 1918 outbreak known as the Spanish Flu. (indiatimes.com)
The 1968 flu pandemic was a global outbreak of influenza that originated in China in July 1968 and lasted until 1969-70. (searchandrestore.com)

The "Combined" category is created by adding emergency department patient visits with diagnosed COVID-19 to those visits with diagnosed influenza and those visits with diagnosed Respiratory Syncytial Virus (RSV) for the given week. (cdc.gov)

Anatomy16

Organisms98

Diseases21

Chemicals and Drugs40

Analytical, Diagnostic and Therapeutic Techniques and Equipment30

Phenomena and Processes45

Disciplines and Occupations1

Technology, Industry, Agriculture2

Information Science3

Named Groups1

Health Care15

Geographicals3

H3N232

Outbreaks15

Pdm096

H5N121

H1N23

Hemagglutinin12

Infection26

Neuraminidase5

Type of influenza virus1

Proportion of influenza1

H9N21

Predominant3

Endemic in humans1

Known as swine flu2

Positive for influenza2

Pandemic of the 21st ce1

Illness13

Antibodies5

Immunity6

Detect Influenza C vir1

Viral10

Rapid influenza diagnostic tests1

Reported influenza type2

Circulate2

Seasonal and pandemic influenza1

Vaccination9

Protein8

1918 flu pand1

Avian influenza viruses1

Change in the influenza1

Hong Kong3

Vaccines8

Cases of influenza1

Different influenza2

Infects2

Laboratory7

Strain of influenza1

Exposure to influenza2

Characterization2

Respiratory virus2

Prevalence1

Diagnostic2

Surveillance for influenza1

Isolates5

Hydroxyl radicals2

Effectiveness2

Detections3

Epidemiological1

Swine influenza5

Epidemic4

Severe2

Among influenza2

Humans8

Hospitalization1

Universal influenza3

Vaccine is available2

Infect3

Epidemiology1

Antigenic drift2

Virology1

Strains include1

Outbreak5

Diagnosed COVID-191