WEDNESDAY, Nov. 4 (HealthDay News) -- When the news broke on Wednesday that a domestic cat had come down with H1N1 swine flu, probably transmitted to the feline by sick owners, many people no doubt wondered how vulnerable their own pets were to the illness.

So, does Fluffy or Fido need protecting from this strain of flu? The answer, experts say, is basically no.

While the H1N1 flu currently circulating can jump easily from person to person, it does not travel well from humans to animals or animals to humans, except in a few rare instances.

"This really is not a practical issue at this point," said Dr. Chris Olsen, a professor of public health and associate dean for academic affairs at the University of Wisconsin School of Veterinary Medicine. "Is that to say it's not possible? No."

And even when inter-species transmissions do occur, the H1N1 virus seems more likely to move from humans to animals, rather than the other way around.

As reported Wednesday by the Associated Press, veterinarians at Iowa State University College of Veterinary Medicine announced the first laboratory-confirmed case of H1N1 infection in a cat. Veterinarian Dr. Brett Sponseller said two of three people who lived in the house with the 13-year-old feline had shown flu-like symptoms before the animal became ill. The cat was treated and has since recovered, the AP said.

Olsen said there have also been reports of the virus crossing from humans to livestock -- in particular pigs and turkeys and mostly in agricultural settings.

There have been instances "where the current pandemic virus has been isolated from pigs [the first identified at the Minnesota state fair in August], and [some] instances from turkeys. But, in all of those cases, it's quite clear that the person was the source of infection for the animals, not the other way around," Olsen said.

Several cases of pig-to-human and human-to-pig transmission of the seasonal flu have been documented but it's mostly in agricultural settings, added Dr. John Treanor, director of the infectious diseases division at the University of Rochester Medical Center in New York.

In fact, the U.S. Department of Agriculture said Wednesday that it had detected H1N1 in a commercial herd of pigs in Indiana, the AP reported. Again, both the pigs and the humans caring for them recovered from the flu, the news agency said.

According to Olsen, the livestock industry already has elaborate biosecurity precautions in place -- everything from asking about workers' health, to protective clothing, to having employees shower before entering or leaving a facility.

Although it's called the swine flu, the H1N1 virus is no longer really a pig virus. "This has been a human-adapted virus since we first recognized it in the early spring of this year," Olsen said, adding, "You absolutely cannot get it from what you eat."

And dog and cat owners don't need to take any extra precautions when it comes to the H1N1 flu, even though there have been instances of animals contracting, and sometimes even passing on, the regular seasonal flu.

Ferrets, for instance, are generally susceptible to the seasonal flu, and the AP reported Wednesday that H1N1 infection has been confirmed in two ferrets, one in Nebraska and the other in Oregon.

"Not only can they be infected with the flu but they are clearly able to transmit the flu back to people," Treanor said. "This is how flu viruses were first discovered. They [researchers] were looking at what the cause of flu would be, back in England in the 1930s, and noticed when they infected ferrets with material from the flu lab, workers got the flu from the ferrets. That led to the discovery of the influenza as the cause of flu."

Olsen added: "There are also reports of the human influenza virus going from people to dogs but this is, again, a rare occurrence."

Dogs can get something called the canine influenza virus, but that "has adapted itself to dogs and really is a dog pathogen at this point," Olsen said. It originally came from horses and mainly affects canines in an animal shelter.

Similarly, a recently developed dog flu vaccine has nothing to do with H1N1, said Dr. Bonnie Beaver, a professor in the department of small animal clinical sciences at the Texas A&M University College of Veterinary Medicine & Biomedical Sciences. "It's for a totally separate disease. It's not something people get."

"Our concern is transmission from human-to-human but we do need to protect pigs [and turkeys]," she said.

"Each animal tends to get its own kind of flu," Treanor said.

More information

Visit the U.S. Centers for Disease Control and Prevention for more on H1N1 flu.

(HealthDay News) -- A food allergy -- commonly to edibles such as shellfish, nuts, wheat, eggs or milk -- often has telltale warning signs.

The American Academy of Allergy Asthma and Immunology offers this list of possibilities:

• Skin that itches, turns red or develops a rash.
• Watering, tearing eyes that may also itch.
• Itching or congestion of the nose.
• Diarrhea, abdominal pain, cramping or vomiting.
• Swelling.

Difficulty breathing, wheezing, chest tightness, tingling of the extremities, or constriction of the throat indicate a serious allergic reaction that requires immediate medical attention.

TUESDAY, Nov. 3 (HealthDay News) -- World Trade Center rescue and cleanup workers have asthma rates twice that of the general population, a new study shows.

In 2005, about 8 percent of workers and volunteers who had spent time at Ground Zero reported having an asthma attack during the previous year, compared to about 4 percent of the general population. The rate of asthma attacks among World Trade Center workers had been less than 1 percent in 2000.

Reports of problems with asthma continued to rise for several years after the attacks. Less than 3 percent of World Trade Center workers reported ever having been diagnosed with asthma attacks pre-9/11, while 16 percent reported in 2005 through 2007 that they had asthma attacks at some point.

"Twice as many World Trade Center responders are suffering from asthma when compared to those their age from the general population," said senior study author Dr. Paul Enright, a research professor of medicine at the University of Arizona.

The study was to be presented Tuesday at the American College of Chest Physicians' annual meeting in San Diego.

Researchers followed about 20,000 responders who received an initial medical exam between July 2002 and December 2007 at a World Trade Center Medical Monitoring and Treatment Program clinic.

Participants were asked if they had experienced an asthma attack in the last year, and whether they had ever been diagnosed with asthma.

The average amount of time spent at World Trade Center sites was about 80 days. About 86 percent of the law enforcement, construction and other rescue, recovery and debris removal workers in the study were men, 59 percent were white and their mean age was 43.

Previous research has found that new asthma diagnoses peaked soon after 9/11 and then fell to closer to normal in the ensuing years. A study in the August issue of the Journal of the American Medical Association found that most new asthma diagnoses --- that is, people who were asthma-free prior to the attacks -- occurred in the 16 months after the attacks, said Lorna Thorpe, deputy commissioner of epidemiology for the New York City Health Department and senior author of that study.

This study is different in that it measures not new diagnoses, but actual asthma attacks.

One drawback to the new study is that the group of patients who were followed wasn't static. Because people can drop in and out of the monitoring program, those who came for their initial evaluation years after the attacks may have been more likely to be among those whose health wasn't improving.

"The question is, are the people who stay in and keep being seen the sicker ones while the healthier ones drop out? If so, that may explain the reason for the rise in asthma over time," Thorpe said.

Furthermore, she added, it would be interesting to know the mental state of those who continue to experiencing asthma attacks. Coughing and wheezing due to asthma could bring back memories of the horror, triggering emotional stress that in turn could make asthma attacks worse.

"The physical health conditions and the mental health conditions are highly overlapping," Thorpe said.

Dr. Norman H. Edelman, chief medical officer for the American Lung Association, said it was important to continue to follow responders and their asthma rates.

Typically, asthma comes on quickly after the lungs are exposed to the toxic pollutants or caustic dust that resulted from the blasts, then declines as the lungs heal.

"Ordinarily, when people get exposed to toxic stuff, you get an immediate reaction. We don't expect a delayed effect," Edelman said. "We saw 9/11 responders who got sick pretty quickly. Some got better. Some did not. What we haven't seen are people who present with asthma two or three years later related to 9/11."

Diseases of the spongy part of the lungs, such as mesotheliomia from asbestos exposure, may take years or decades to develop. But asthma is a disease of the airways, which is typically apparent right away.

Researchers said there was no evidence that asthma rates continued to rise after 2005.

"However, the majority of those who developed asthma during or after their World Trade Center exposures have continued to have asthma attacks many years later," Enright said. "Their asthma did not spontaneously resolve within a few months after their WTC exposure ceased."

More information

The American Lung Association   has more on asthma.