Novel Influenza A Virus (H1N1, H1N2, H5N1, H7N3, and now H7N9) - Minnesota Dept. of Health

Novel Influenza A (H5N1, H5N2, H7N3, H7N9)

New (novel) influenza A viruses have the potential to cause a pandemic if the virus were to change to become easily and sustainably spread from person-to-person.

Background

  • New (novel) influenza A viruses have the potential to cause a pandemic if the virus were to change to become easily and sustainably spread from person-to-person.
    • An influenza pandemic is a global outbreak of a new influenza A virus that is very different from current and recently circulating human seasonal influenza A viruses.
    • Influenza A viruses are constantly changing, making it possible on very rare occasions for non-human influenza viruses to change in such a way that they can infect people easily and spread efficiently from person to person.
  • Because novel viruses are new to humans, very few people will have immunity, and a vaccine might not be widely available.
  • How sick people get will depend on the characteristics of the virus, whether or not people have any immunity to that virus, and the health and age of the person being infected.
  • Global influenza surveillance, both epidemiologic and virologic, is the foundation of influenza preparedness and response for influenza viruses.

Viruses of Special Concern

Highly Pathogenic Avian Influenza (HPAI)

Human infections with novel avian influenza virus are concerning because flu changes rapidly, and animal flu viruses can change such that they may gain the ability to infect people easily and spread among people .

How is HPAI spread?

  • Avian influenza viruses are spread through direct contact with infected birds or through contact with contaminated bedding, feed or water.

Can humans be infected with HPAI?

  • Some highly pathogenic avian flu viruses can infect people causing mild to severe respiratory illness.
  • In most cases, people are infected after direct contact with birds that are sick with or died from highly pathogenic avian influenza.
  • Symptoms in infected people can include influenza-like illness (e.g., fever, aches, respiratory symptoms) and red, itchy eyes.
  • Person-to-person transmission of avian influenza viruses is very rare.
  • HPAI does not pose a health risk to the public. Only persons who have direct contact with infected birds are potentially at risk.
    • People in contact with infected birds should be monitored by public health to make sure they don't become sick. It is also recommended for them to take antiviral medication.

Novel H7N9 virus is an avian influenza virus.

Human infections with an Asian lineage avian influenza A (H7N9) virus (“Asian H7N9”) were first reported in China in March 2013. Annual epidemics of sporadic human infections with Asian H7N9 viruses in China have been reported since that time. In late 2016, some Asian low pathogenicity Asian H7N9 viruses developed mutations that made them highly pathogenic in poultry. These Asian HPAI H7N9 viruses continue to be associated with human infections in China.

  • Most human infections with avian influenza viruses, including Asian H7N9 virus, occur after exposure to infected poultry or contaminated environments.
  • Asian H7N9 viruses have not been detected in people or birds in the United States.
  • You cannot get infected with these viruses from properly handled and cooked poultry or eggs.
  • More information: CDC: Asian Lineage Avian Influenza A (H7N9) Virus

H5N1 is a highly pathogenic avian (bird) flu virus that has caused serious outbreaks in domestic poultry in parts of Asia and the Middle East. Since its widespread re-emergence in 2003, rare, sporadic human infections with this virus have been reported in Asia, and later in Africa, Europe, and the Middle East.

  • Most human cases of "highly pathogenic" H5N1 virus infection have occurred in people who had recent contact with sick or dead poultry that were infected with H5N1 viruses. About 60% of people infected with the virus died from their illness.
  • Unlike other types of flu, H5N1 usually does not spread between people.
  • To date, there have not been any reports of HPAI Asian H5N1 virus infections in people in the United States and Asian H5N1 has never been detected in U.S. birds or poultry. (The H5N1 virus recently detected in U.S. wild birds is a new mixed virus (a reassortant) that is genetically different from the Asian avian H5N1 viruses).
  • You cannot get infected with these viruses from properly handled and cooked poultry or eggs.
  • More information: CDC: Highly Pathogenic Asian Avian Influenza A (H5N1) Virus

H5N2 is a highly pathogenic avian (bird) flu virus that has caused serious outbreaks in domestic poultry in parts of Asia and the Middle East.

Although H5N1 does not usually infect humans, nearly 600 cases of human cases of H5N1 have been reported from 15 countries since 2003 and in 2011 62 human H5N1 cases and 34 deaths were reported from five countries (Bangladesh, Cambodia, China, Egypt, and Indonesia).

  • Most human cases of "highly pathogenic" H5N1 virus infection have occurred in people who had recent contact with sick or dead poultry that were infected with H5N1 viruses. About 60% of people infected with the virus died from their illness.
  • Unlike other types of flu, H5N1 usually does not spread between people.
  • There have been no reported infections with these viruses in birds, poultry, or people in the United States.
  • You cannot get infected with these viruses from properly handled and cooked poultry or eggs.
Updated Tuesday, 29-Jan-2019 16:24:31 CST