What is influenza H2N2?
Influenza A virus subtype H2N2 (A/H2N2) is a subtype of Influenza A virus. H2N2 has mutated into various strains including the “Asian flu” strain (now extinct in the wild), H3N2, and various strains found in birds. It is also suspected of causing a human pandemic in 1889.
What is the epidemiology of influenza?
Influenza occurs in distinct outbreaks of varying extent every year. This epidemiologic pattern reflects the changing nature of the antigenic properties of influenza viruses, and their subsequent spread depends upon multiple factors, including transmissibility of the virus and the susceptibility of the population.
How did influenza get to humans?
Influenza is caused by a virus that is transmitted from person to person through airborne respiratory secretions.
What is the significance of influenza?
Flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs. It can cause mild to severe illness, and at times can lead to death. The best way to prevent flu is by getting a flu vaccine each year.
What type of virus was H2N2?
In February 1957, a new influenza A (H2N2) virus emerged in East Asia, triggering a pandemic (“Asian Flu”). This H2N2 virus was comprised of three different genes from an H2N2 virus that originated from an avian influenza A virus, including the H2 hemagglutinin and the N2 neuraminidase genes.
Is there a vaccine for H2N2?
H2N2 live attenuated influenza vaccine is safe and immunogenic for healthy adult volunteers.
How many types of influenza viruses are there?
There are four types of influenza viruses: A, B, C and D. Human influenza A and B viruses cause seasonal epidemics of disease (known as flu season) almost every winter in the United States.
What is the incubation period of influenza?
The incubation period of influenza is 2 days long on average but may range from 1 to 4 days in length.
When did flu virus start?
It is impossible to know when an influenza virus first infected humans or when the first influenza pandemic occurred. Possibly the first influenza epidemic occurred around 6,000 BC in China, and possible descriptions of influenza exist in Greek writings from the 5th century BC.
When did the H1N1 flu start?
2009-2010 H1N1 influenza (formerly called swine influenza) outbreak. Human cases of influenza A (H1N1) were reported worldwide. In 2009, cases of influenzalike illness were first reported in Mexico on March 18; the outbreak was subsequently confirmed as H1N1 influenza A.