A novel/variant influenza A virus is an influenza A virus subtype that is different from currently circulating human influenza H1 and H3 viruses. Novel subtypes include, but are not limited to H2, H5, H7 and H9 subtypes. Influenza H1 and H3 subtypes originating from a non-human species or from genetic reassortment between animal and human viruses are also novel/variant subtypes.

When an influenza virus that normally circulates in swine (but not people) is detected in a person, it is called a “variant influenza virus.” For example, if a swine origin influenza A H3N2 virus is detected in a person, that virus will be called an “H3N2 variant” virus or “H3N2v” virus.

An illness compatible with influenza virus infection. Influenza usually comes on suddenly, one to four days after the virus enters the body, and may include these symptoms:

• Fever or feeling feverish/chills
• Cough
• Runny or stuffy nose
• Sore throat
• Headache
• Tiredness (can be extreme)
• Muscle or body aches

Among children, otitis media, nausea, vomiting, and diarrhea are common. Some infected persons are asymptomatic.

People infected with swine influenza A viruses will exhibit symptoms similar to seasonal influenza. 

People infected with avian influenza A viruses may have a wide range of illness including mild respiratory symptoms and conjunctivitis to lower respiratory tract disease, acute respiratory distress syndrome (ARDS) and death.

Most human novel/variant influenza A infections are thought to be the result from direct contact with infected animals.  Humans are thought to become infected with a novel/variant influenza A virus when enough virus gets into a person's eyes, nose or mouth, or is inhaled. This can occur when virus is in the air, via droplets or possibly dust, and a person breathes it in, or when a person touches a contaminated surface that has the virus on it then touches their mouth, eyes or nose.  The exact spread of novel/variant influenza A viruses is not completely understood. With the exception of novel 2009 H1N1 virus, the spread of novel/variant influenza A virus between humans has been limited.

Novel subtypes will be detected with methods available for detection of currently circulating human influenza viruses at the DSHS State Laboratory or one of the Laboratory Response Network (LRN) laboratories within the state (e.g., real-time reverse transcriptase polymerase chain reaction [RT-PCR]). Confirmation that an influenza A virus represents a novel/variant virus will be performed by CDC’s influenza laboratory.

Yes. There has been one influenza A (H1N1) variant virus case detected in Texas since 2005.

Currently, the best way to prevent infection to avoid sources of exposure whenever possible.  So stay away from sick animals such as poultry or swine. Other activities that may be performed to prevent getting influenza include:

• Hand washing and using alcohol-based hand sanitizers,
• Covering your coughs and sneezes with a disposable tissue or your arm or sleeve,
• Avoiding touching your eyes, nose, or mouth,
• Avoiding close contact with persons who are ill,
• Staying home when you are ill, and
• Taking antiviral medications if prescribed by your doctor.   
  • In certain situations (e.g., influenza outbreaks in settings like nursing homes), antiviral medications may be prescribed to high-risk individuals to prevent them from developing influenza illness after exposure to infected individuals.