Dogs are not susceptible to the H5N1 bird flu.
Humans
The swine flu H1N1/09 virus survives as do all viruses, by invading a host to support it and do its work to reproduce. Viruses can not live without a host to infect. That is why some viral diseases have been eliminated by vaccination programs, if everyone is vaccinated, no one becomes a host. Don't let flu viruses survive inside you, get a flu vaccination every year prior to flu season.
To continue to replicate and exist, a flu virus must be in a host animal's cells. They can be grown in cultures (and eggs) for creating vaccines, but need a living host for long term activity and to "live".
Parasite. Parasites feed off of hosts.
Yes. People with Anorexia Nervosa are susceptible to many infections and diseases since they have inadequate nourishment and injury to organs from starvation that causes them to no longer have resistance to even minor infectious diseases like the flu, as well as to secondary conditions that make them unable to fight disease.
Swine flu does not have an affect on the circulatory system. It does affect the Cardiovascular system and puts it under great stress, that's why people with heart disease are more susceptible to it.
it is the gene that allows the flu virus to escape a host cell
Swine flu is a virus and viruses reproduce by injecting it's own DNA into a host cell and then that cell is corrupted and taken over and becomes a flu cell. =]
The state of the immune system can both improve and get worse during pregnancy, and this varies with the individual.
Influenza is everywhere there are people and other species that are susceptible to the flu. If this is referring specifically to the H1N1/09 swine flu in 2009 during the pandemic, it did eventually spread to every continent and every country in the world.
Not the human flu, but dogs are susceptible to the canine version of colds and flu (which are caused by different things) The canine flu shows symptoms very close to kennel cough but they ARE NOT the same thing. The canine flu is almost the same as horse flu, and dog flu can be described as H3N8. many dogs recover within a few weeks on their own, beware that dogs may not show symptoms but are still contagious to other dogs. Humans and dogs can not transmit flu from each other, they are different strains.