There are two big concerns with the various bird flu viruses, one is that they cause a shortage of food because entire chicken flocks have to be killed.
The other that if it ever becomes possible to pass the infection from person to person, especially if it happens through airborne transmission. The biggest risk for this is a new strain of the virus.
Unfortunately it has just been confirmed that this occurred in a Zhejiang Province, China, hospital in January 2014.
The point here is that it is very likely you will see versions of this story in the mainstream press, possibly with hype designed to make this appear really threatening.
It probably isn’t all that serious which is what you should bear in mind until or unless some new concerns surface.
Right now the important take away is that bird flu patients should be kept isolated from other patients the same way other infections patients are isolated. Until now this has not been a concern.
The CDC (Centers for Disease Control) has released a report, “Nosocomial Co-Transmission of Avian Influenza A(H7N9) and A(H1N1)pdm09 Viruses between 2 Patients with Hematologic Disorders.”
Translated to an Earth language, what this means is that two elderly men with different kinds of blood cancers in a hospital ward but otherwise not connected in any way, have the identical bird flu strains and one caught it from the other almost certainly via an airborne vector. Nosocomial simply means caught in a hospital.
The summary line most important in the long scientific report is, “These findings strongly suggest limited nosocomial co-transmission of H7N9 and pH1N1 viruses from 1 immunocompromised patient to another.” http://wwwnc.cdc.gov/eid/article/22/4/15-1561_article
This IS an isolated incident, and no cause for panic, but it is also the first solid evidence of airborne transmission between humans with a new virus, the ONLY barrier to bird flu becoming a dangerous pandemic.
Details – translation of a CDC abstract of the report.
A nosocomial (hospital acquired) cluster (two patients) both had avian influenza A(H7N9) and A(H1N1)pdm09 (pH1N1) viruses at a hospital in Zhejiang Province, China, in January 2014.
The index case-patient (first person infected) was a 57-year-old man with chronic lymphocytic leukemia (cancer) who had worked with live poultry and acquired both the H7N9 and pH1N1 viruses.
A second person in the same ward for 6 days, a 71-year-old man with polycythemia vera (a blood cancer which starts in the bone marrow) acquired infection with H7N9 and pH1N1 viruses. The incubation period for the second case-patient was estimated to be less than 4 days.
Both of these already very sick patients died of multiple organ failure.
103 people who had close contact with these two patients were tested and none of them tested positive for the H7N9 virus.
The bottom line is that it is extremely difficult to PROVE human to human transmission of avian flu which is why this is both big news and why it took so long to report.
By the beginning of 2016 a new avian influenza A virus, A(H7N9) had caused 676 lab-confirmed cases in humans and 275 associated deaths since it was first identified in March 2013.
Bird flu is mainly found in China and the CCDCP (Chinese Center for Disease Control and Prevention) is vigilant for any changes in avian influenza and particularly whether new versions are more dangerous for humans.