The influenza type for reported seasonto date cases includes 82% influenza a, 17% influenza b, and 1% untyped. The virus had spread to the us from an outbreak in mexico the u. It originated in pigs but is spread primarily from person. Twentysix laboratorypositive cases of influenza 21 influenza a h3, three influenza a h1n1, and two influenza b. Its been a little over a decade since the world experienced its last pandemic, the 2009 h1n1 swine flu. The who gave recommendations to mohp for improving early detection and notification of influenza like illness and severe respiratory events.
Weekly influenza respiratory illness activity report. Pandemic influenza a virus h1n1 2009 continued to circulate as a seasonal virus among the population during autumn and winter 20102011 with a recurrence of influenza morbidity. Nearly 60% of the flu associated hospitalizations reported to cdcs influenza surveillance system were in people 18 to 64 years old. Influenza pandemic h1n1 of 2009, also called h1n1 flu, byname swine flu, the first major influenza outbreak in the 21st century, noted for its rapid global spread, which was facilitated by an unusually high degree of viral contagiousness. Activity varied from low to high and was associated with the cocirculation of influenza a h1n1. Influenza virus infections in humans february 2014. Three kinds of flu viruses commonly circulate among people today.
It is too early to know whether the season has peaked or if flu activity will increase again. A total of 57 patients were studied, however only 39 patients were later confirmed as influenza a h1n1 2009 rtpcr positive and were included in the statistical analysis. Eine zusammenfassung aktueller informationen zu influenza a h1n1. Bureau of infectious disease control infectious disease. Highlights for the upcoming 202014 season include 1 this years trivalent influenza vaccine contains an acalifornia72009 h1n1 pdm09like virus same as 201220. The viral load peaked on day 1 and became undetectable on day 5, and an antibody response developed. Here, we report 40 complete genome sequences of influenza a h1n1 strains isolated from 33 nonhospitalized and 7 hospitalized patients during the 20 2014 epidemic season in finland. H1n1 influenza is a new strain of swine influenza a h1n1 caused by a respiratory disease of pigs.
Its called swine flu because in the past, the people who caught it had direct contact with pigs. Influenza a h1n1 infections carry a significant mortality risk. For other names, see the nomenclature section below. In mexico, the rates of laboratoryconfirmed influenza a h1n1 hospitalizations and deaths were shown to be significantly higher p 2014. Genesis and pathogenesis of the 1918 pandemic h1n1 influenza a. This guideline adapts the general definition of severe influenza from influenza related severe acute respiratory illness. Oseltamivirresistant influenza ah1n1 pdm09 viruses, united. Swine influenza is an infection caused by any one of several types of swine influenza viruses. As of 2009, the known siv strains include influenza c and the subtypes of influenza a known as h1n1, h1n2, h2n1, h3n1, h3n2, and h2n3. Among people 65 years and older, there were an estimated 8.
A new flu virus emerges the h1n1 pdm09 virus was very different from h1n1 viruses that were circulating at the time of the pandemic. As a whole, the recent viruses have drifted from the prototype acalifornia72009 virus by ca. Seasonal influenza activity, september 20 january 2014. The 1976 h1n1 swine flu was a very different virus from the 2009 h1n1 swine flu, which combines elements from flu viruses that evolved in birds, humans, and pigs.
The causal agent, in fact, is a swine origin influenza a h1n1 virus soiv that is characterized by a unique combination of gene segments that has not been previously identified among human or swine influenza a viruses. During the 20 2014 season, cdc received reports of severe flu illness among young and middleaged adults, many of whom were infected with the 2009 h1n1 virus. Pharmacological management of pandemic influenza a h1n1 2009 part i. Volume 20, number 9september 2014 swine tohuman transmission of influenza ah3n2 virus at agricultural fairs, ohio, usa, 2012 andrew s. The reported influenza hemagglutinin sequences from india indicate. In years in which h3n2 is the predominant strain, there are more hospitalizations. Seasonal influenza activity, february september 20. Two correctional facility outbreaks were caused by influenza 1 influenza a h1n1 and 1 influenza b and one was caused by influenza like illness. Swine influenza virus siv or swine origin influenza virus soiv is any strain of the influenza family of viruses that is endemic in pigs. Measures to minimize influenza transmission at swine. The coronavirus outbreak is more severe than the 2009 outbreak of h1n1, or swine flu.
Areinfluenzasentinel 202014 gesunde sachsen freistaat. H1n1 2009 h1n1 seasonal a 20082009 influenza season. A recent increase in reported cases of severe influenza among young and middleaged adults infected with influenza ah1n1pdm09 ph1n1 virus have been reported nationally and in contra costa county. In the northern hemisphere, flu season can begin as early as october and last as late as may.
This time shift is due to the emergence of pandemic h1n1 in may 2009. In 20142015, 80% of influenza cases reported from icus were infected with influenza type a and 20% with type b. Table 2 and and3 3 show the percentage of total rna found in each stage of the may impinger table 2 and the % of rna collected in each stage during each procedure table 3. Complete genome sequences of influenza ah1n1 strains. As of december 2009, the most prevalent circulating influenza virus was pandemic h1n1. During october 1, 20april 30, 2014, a total of 4,968 influenza ah1n1pdm09 virus specimens collected from 50 us states and 2 territories were tested for antiviral susceptibility 1,811 virus isolates and 3,157 clinical specimens. That changed several years ago, when a new virus emerged that. How the coronavirus compares to sars, swine flu, and other. Isolation and characterization of the seasonal h1n1 influenza a virus 2014 from an egyptian patient. Influenza a virus subtype h1n1 a h1n1 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.
During this period niosh conducted several health hazard evaluations to assess workplace exposures to flu. First, as the majority of human population has little or no preexisting immunity to the virus, the impact of the infection has been in a wider age. Volume 20, number 9september 2014 risk factors for severe influenza arelated pneumonia in adult cohort, mexico, 2014. Recommended composition of influenza virus vaccines for. Influenza viruses are constantly changing either through the collection of minor point mutations or through. Pdf direktor des instituts fur virologie, veterinarmedizinische fakultat, universitat leipzig, stand. Influenza a h5n6 virus reassortant, southern china, 2014 technical appendix technical appendix figure following pages.
The 2009 pandemic caused by influenza a h1n1 pdm09 virus resulted in more than 18 500 deaths reported worldwide and global estimates that were 15fold higher. Here, we show that recent h1n1 strains possess a mutation that. The pandemic h1n1 2009 influenza virus differs in its pathogenicity from seasonal influenza in two key aspects. Substantial morbidity and mortality associated with pandemic. Public health reporting of aggregate influenza data phraid select commercial laboratories in washington report the number of influenza tests performed and the number. The 2014 2015 h1n1 outbreak in india has reportedly led to 800 fatalities. This study describes inpatients with suspected and confirmed influenza a h1n1 infection who were prescribed oseltamivir, the risk factors associated with infection, the association between infection and mortality, and the factors associated with inhospital mortality in infected patients. The 2009 flu pandemic in the united states was a novel strain of the influenza a h1n1 virus, commonly referred to as swine flu, that began in the spring of 2009. Reassortment of strains of influenza a h1n1 of avian, porcine and human origin. We analyzed the geographic dissemination of the 202014 ah1n1 outbreak in mexico based on state and agespecific time series of laboratoryconfirmed hospitalizations according to day of symptom onset.
S and others published swine flu and the current influenza a h1n1 pandemic in humans. Swine flu, also known as the h1n1 virus, is a relatively new strain of an influenza virus that causes symptoms similar to the regular flu. In birds, humans, and pigs, the virus has mutated into many strains. Three ou t b r e a k s o f i n f l uen z a 2 influenza a not subtyped and 1 influenza b w e r e reported i n hosp i t a l s from november 20 through may 2014. Current week 14 ending 442020 21 new influenza detections reported 2 new influenza related deaths reported this week. Evaluation of influenza a h1n1 infection and antiviral. Centers for disease control and prevention cdc worked with manufacturers to. Vaccine effectiveness ve against 2009 pandemic influenza ah1n1 virus ah1n1pdm09related medically attended acute respiratory illness maari for the 202014 season among persons aged.
Agespecific a h1n1 influenza hospitalization rates left and a h1n1 inpatient death rates right for the ongoing a h1n1 influenza epidemic 01oct 20 to 31jan 2014 compared to the preceding 201112 a h1n1 epidemic and those of the entire 2009 a h1n1 pandemic period 01apr 2009 to 31mar 2010. Activity varied from low to high and was associated with the cocirculation of influenza ah1n1pdm09, ah3n2 and b viruses. Influenza viruses are cultured in chick embryo and cell culture mdck. In 2009, a new h1n1 influenza virus emerged, causing the first global flu pandemic in 40 years. Seasonal influenza annual epidemiological report for 2014.
Centers for disease control and prevention is now tracking reports of human. Global dissemination of the virus was further expedited by the unprecedented rates of passenger travel. In virology, the pandemic h1n109 virus is a swine origin influenza a virus subtype h1n1 strain that was responsible for the 2009 swine flu pandemic. Pigs can be infected with human, swine and avian origin influenza a viruses. During the 20 2014 influenza season, one such case was reported to dhmh. Seasonal influenza viruses circulate and cause disease in humans every year. Pdf isolation and characterization of the seasonal h1n1 influenza. A, 7,101 influenza b, and 348 untyped have been reported in missouri as of week 2. The reported influenza hemagglutinin sequences from india indicate that these viruses contain amino acid changes linked to enhanced virulence and are potentially antigenically distinct from the current vaccine containing 2009 cal0709 h1n1 viral hemagglutinin. An analysis of the aligned sequences revealed no oseltamivirresistant genotypes. Centers for disease control and prevention cdc estimates there were 60. All ah1n1pdm09 viruses characterised antigenically and.
Here, we present the nearly complete genome sequence of this epidemic strain that was compared to the postpandemic variants of a h1n1 pdm09. The latter are composed of key genes from the 1918 virus, updated by subsequentlyincorporated avian influenza genes that code for novel surface proteins, making the 1918 virus indeed the mother of all pandemics. The 20182019 flu vaccine was 29 percent effective against influenza a and b and 44 percent effective in preventing influenza a h1n1 viruses in the united states. Cdc estimates that so far this season there have been at least 34 million flu illnesses, 350,000 hospitalizations and 20,000 deaths from flu. Recommendations for prevention and control of influenza in. Quoting the 2010 guideline of the world health organization who, severe influenza is defined as follows. Between the spring of 2009 and the spring of 2010, the virus infected as many as 1. Influenza h1 n1 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. Few young people had any existing immunity as detected by antibody response to the h1n1 pdm09 virus, but nearly onethird of people over 60 years old had antibodies against this virus. After the 20092010 h1n1 influenza pandemic, the world health organization who initiated a technical consultation on global influenza surveillance. Disease outbreak control division influenza respiratory disease surveillance report morbidity and mortality weekly report mmwr1. Critically ill patients with influenza ah1n1pdm09 virus.
In virology, influenza a virus subtype h1n1 ah1n1 is the subtype of influenza a virus that. The emergence and transition to pandemic status of the influenza a h1n1 a h1n1 pdm09 virus in 2009 illustrated the potential for previously circulating human viruses to reemerge in humans and cause a pandemic after decades of circulating among animals. Find information on coronavirus disease 2019 covid19. Influenza vaccine effectiveness against 2009 pandemic. Epidemiology currently, who publishes weekly information from global influenza surveillance 5. Between february and september 20, influenza activity was reported in africa, the americas, asia, europe and oceania. We identified 57 episodes of suspected influenza a h1n1 infection in 40 children. Influenza virus strains perennially circulate throughout the world.
Actually, the new h1n1 virus appears to be a mixture of avian, porcine, and human influenza rna. Annual influenza epidemics occur worldwide and cause substantial morbidity and mortality. First human infection with new influenza a h1n1 virus detected in california. Apr 02, 2014 the 2009 pandemic caused by influenza a h1n1 pdm09 virus resulted in more than 18 500 deaths reported worldwide and global estimates that were 15fold higher. In 202014, ah1n1pdm09 virus predominated among icu cases with known subtype, while type b was virtually absent. H1n1 amounts for 2016 which will further impact timing and quantity of supply. Seasonal influenza annual epidemiological report for 201415. The h1n1 influenza pandemic exposed strengths and weaknesses of the global plan in place to deal with emerging infectious disease threats.
A summary of the first yearapril 2009may 2010 background the first influenza pandemic of the st21 century began in north america in early 2009. Apr 11, 2016 in 20142015, 80% of influenza cases reported from icus were infected with influenza type a and 20% with type b. Potential antigenic explanation for atypical h1n1 2014. Due to confidentiality considerations, details of these cases are not discussed in this report. Two correctional facility outbreaks were caused by influenza 1 influenza a h1n1 and 1 influenza b and one was caused by influenzalike illness. Flu vaccination has been shown to prevent flu illnesses, doctors visits and hospitalizations and can be lifesaving in children 20182019 u. Did obama declare swine flu an emergency only after. Nationally, influenza a h1n1 viruses are now the most commonly reported influenza viruses this season. An influenza virus strain, aalmaty6327 2014 h1n1, was isolated in almaty in southeastern kazakhstan during a human population surveillance study in 2014. The three different viral subtypes that circulated in nh during the 201415 influenza season are presented in table 2. Reservoir in rindern hat, wird 2014 als neues genus, influenzavirus d. The purpose of this statement is to update recommendations for routine use of seasonal influenza vaccine and antiviral medications for the prevention and treatment of influenza in children. Influenza ah1n1pdm09 virus infection in a captive giant. This strain is often called swine flu by the public media.
Recommended composition of influenza virus vaccines for use. Pdf molecular characterization of influenza ah1n1pdm09 in. Pandemic preparedness and response lessons from the h1n1. Influenza activity started in week 502014 and lasted until week 202015, as in. Previously, influenza bvictoria viruses predominated nationally. Between september 20 and january 2014, influenza activity was reported in africa, the americas, asia, europe and oceania. Increase in severe influenza cases infected with i nfluenza ah1n1 pdm09 v irus. In the united states between 5% and 20% of the population are infected with influenza every year, resulting in between 3,000 and 49,000 influenza associated deaths. Clinical management of human infection with pandemic. Of influenza a viruses subtyped, 35% were influenza ah1n1pdm09 and 65% were ah3n2. Everyone 6 months and older needs a flu vaccine each year.
We report influenza ah1n1pdm09 virus infection in a captive giant panda in hong kong. Ensuring the country is fully prepared and able to respond quickly and effectively is a top priority for phe and, of course, for the government. Kansas, 1995 2014 each influenza season begins september 1 and ends may 31 of the following year, with the exception of 20082009 september 1, 2008 through april 30, 2009 and 20092010 may 1, 2009 through may 31, 2010. Feb 21, 2014 the h1n1 cases appear to have peaked about 2 weeks ago, said anthony mounts, md, leader of the epidemiologic portion of whos egyptian mission, and numbers are likely to decline going forward. In virology, influenza a virus subtype h1n1 a h1n1 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 spanish flu outbreak it is an orthomyxovirus that contains the glycoproteins haemagglutinin and neuraminidase. It is an orthomyxovirus that contains the glycoproteins haemagglutinin and neuraminidase. The 20142015 h1n1 outbreak in india has reportedly led to 800 fatalities. In all episodes, children were treated with oseltamivir and antibiotics until influenza a h1n1 results were received.
The 20092010 influenza season saw the emergence of the 2009 h1n1 influenza flu virus which caused the first influenza pandemic global outbreak of disease caused by a new flu virus in more than 40 years. The single best way to prevent the flu is get a flu vaccine. Influenza aerosols in uk hospitals during the h1n1 2009. During the 202014 influenza season, h1n1 viruses caused an unusually high level of disease in middleaged adults. Within a short time of the initial emergence of a h1n1 pdm09 virus, novel reassortants were isolated from swine. Activity varied from low to high and was associated with the cocirculation of influenza a h1n1 pdm09, ah3n2 and b viruses. Viral gene sequences to assist update diagnostics for swine influenza ah1n1 pdf. The subject disease is severe seasonal influenza infection. Other h1 viruses have not been detected since 2010. Influenzaavirus h1n1 ah1n1 bezeichnet einen subtyp des influenzaa virus gattung.
Intense seasonal ah1n1 influenza in mexico, winter 202014. The reported influenza hemagglu tinin sequences from india. All of the 2014 2015 influenza vaccine was made to protect against. When animal influenza viruses infect their natural animal host, they are named for that host, as in avian influenza viruses, swine influenza viruses, equine influenza viruses, etc. Below is a timeline of major events that took place during the 2009 h1n1 pandemic.
Activity varied from low or moderate to high due to the circulation of influenza ah1n1pdm09, ah3n2 and b viruses. Spatial distribution of ah1n1 influenza in winter 202014 and reproduction number estimate. Influenza spotlight emerging infectious diseases journal. Molecular characterization of influenza ah1n1pdm09 in cameroon during the 20142016 influenza seasons.
Influenza ah5n6 virus reassortant, southern china, 2014. On 17 march 2014, three cases were confirmed with a possible fourth awaiting results occurring at the centre for addiction and mental. President barack obama had waited until millions were infected and thousands were dead from swine flu, the h1n1. Laboratory diagnosis of influenza a h1n1 was performed by means of polymerase chain reaction analysis of nasopharyngeal wash specimens. Phylogenetic relationship of genes of aduckguangdonggd01 2014 h5n6, a novel virus isolated from ducks in guangdong province in southern china during march 2014, compared with reference strains from genbank. In 20 2014, ah1n1pdm09 virus predominated among icu cases with known subtype, while type b was virtually absent. Introduction influenza flu is a contagious respiratory illness caused by the influenza virus. Cdc estimates that the overall burden of influenza disease estimated across all age groups was 40 million flu illnesses, 19 million flu associated medical visits, and. Before a 2009 global outbreak of h1n1 influenza, persontoperson transmission was limited. Seasonal influenza annual epidemiological report 2016 en pdf261. Influenza viruses typically cause a higher disease burden in children and the elderly, who have weaker immune systems.