True/False: Only exotic Newcastle's disease has been seen in the U.S.; highly pathogenic avian influenza has not yet occurred.

• A. True
• B. Not sure
• C. False
• D. All of the above

Answer: (C)

The important idea here is that more than one major avian disease has appeared in the United States. Exotic Newcastle disease is not the only serious threat that has been seen; highly pathogenic avian influenza has also occurred in U.S. poultry and wild birds, sometimes in large outbreaks that prompted widespread control and surveillance efforts. Because HPAI outbreaks have happened in the U.S., the statement that HPAI has not occurred is inaccurate. Understanding the two viruses helps: exotic Newcastle disease is caused by a paramyxovirus and is exotic to the U.S., while highly pathogenic avian influenza is an influenza A virus with documented outbreaks in the United States.