27 February 2018
TUESDAY, Feb. 27, 2018 (HealthDay News) — If you’re unlucky enough to come down with the flu, you can blame your own body for your fever, cough, muscle aches and head-to-toe distress, experts say. Most of influenza’s misery is caused by the human body itself, or more precisely the immune system’s response to the virus. “Many of the things that feel bad are the body’s attempts to get rid of the pathogen that’s causing the mischief,” said Dr. Alan Taege, an infectious disease specialist with the Cleveland Clinic. When your body has prior experience with a flu virus, it already knows how to send the right antibodies out to fight off the bug, Taege said. In those cases, folks might not even notice they’ve had a brush with influenza. But when faced with a new invader, the immune system goes into overdrive. It floods the body with a host of immune system-stimulating biochemicals called cytokines. And that helps to explain why this year’s flu season has been so severe — many Americans haven’t had enough prior exposure to the H3N2 flu strain that’s causing such havoc, doctors say. According to Dr. Gregory Poland, “As a result of fighting off the infection, our body releases an army of chemicals, and those are meant to stimulate the immune system. Think of them as chemicals released into the blood to flog the immune cells of the body to rev up, divide, and attack these viral infidels.” Poland is a vaccine expert with the Mayo Clinic in Rochester, Minn. Cytokines also cause inflammation throughout the body, and that inflammation leads to many of flu’s most wretched symptoms, Poland and Taege said. For instance, muscle, joint and body aches occur due to cytokine-prompted inflammation in the limbs. Inflamed air passages produce mucous, causing a runny nose, coughing and sneezing. Cytokines also cause the body to raise its temperature, resulting in fever. What’s more, the cytokine interferon has been linked to symptoms of headache. It’s also possible that blood vessels in the brain dilate in response to fever, creating a headache by increasing pressure inside your head. Taege likens this inflammation to your skin’s response to a very hot object. You feel pain, and the place that’s been seared will turn red and possibly blister. Over a few days, the burned spot starts to calm down and heal. “The cytokines produce an inflammatory reaction that doesn’t necessarily cause a blister like a thermal burn, but if you look at the throat it can look red. If you look at the airways they can look red,” Taege said. “This is inflammation, and how it interacts with the cells and injures the cells goes on to produce symptoms.” Experiments have shown that people exposed to artificial cytokines will develop symptoms of flu infection, even though the virus isn’t present, Taege said. This is not to say the virus can’t do damage on its own, Poland added. “We recently had a young healthy boy die of influenza,” Poland said. “Autopsy showed the virus had invaded his heart and he died as a result of that.” Flu virus infecting the lungs can directly cause shortness of breath, fever and pneumonia, Poland added. But many deaths caused by flu occur due to a “cytokine storm” — an overwhelming flood of immune chemicals prompted by first exposure to a new and dangerous influenza virus, Poland said. Many of the young and healthy people killed by the flu during the 1918 influenza pandemic are believed to have died due to cytokine storm. “The body is so massively activated in an attempt to fight off this virus that it releases too many of these internal chemicals,” Poland said. That’s why flu shots are recommended. They teach the body how to produce antibodies to fight off the flu without mounting a full-fledged cytokine defense, Taege and Poland explained. With flu activity still elevated across much of the United States, Taege said the vaccine can help limit its damage. “Should you encounter the flu virus, then it can control it much more quickly,” Taege said. People treating flu symptoms most often are treating the inflammation produced by cytokine release. That’s why nonsteroidal anti-inflammatory drugs (NSAIDs) like aspirin and ibuprofen (Motrin, Advil) are recommended, Poland said. You should also rest, drink plenty of fluids and continue to eat, Poland said. Flu sufferers who remain active are adding to the body-wide inflammation caused by cytokines, Poland said. And those who stop eating are robbing the body of energy it needs to recover. “One of the effects of this cytokine release is it really revs up your metabolism,” he said. “You actually need more caloric intake to sustain the body.” More information The U.S. Centers for Disease Control and Prevention has more about flu symptoms and complications.
12 February 2018
MONDAY, Feb. 12, 2018 (HealthDay News) — As a particularly nasty flu season rages across the United States, scientists have found a powerful new disinfectant that makes “light” work of the virus. Researchers say a certain spectrum of ultraviolet light — called far-UVC — easily kills airborne flu viruses while posing no risk to people. It could offer a new, inexpensive way to eliminate airborne flu viruses in indoor public spaces such as hospitals, doctors’ offices, schools, airports and aircraft, said the team from Columbia University Medical Center in New York City. The disinfecting success of initial experiments still need to be confirmed, said lead research David Brenner. But he believes “the use of overhead, low-level far-UVC light in public locations would be a safe and efficient method for limiting the transmission and spread of airborne-mediated microbial diseases, such as influenza and tuberculosis.” As the researchers explained, broad-spectrum UVC light kills viruses and bacteria, and it is currently used to decontaminate surgical equipment. But this type of light can cause skin cancer and cataracts, so it’s not used in public spaces. However, Brenner and his colleagues wondered if a much narrower spectrum of ultraviolet light, far-UVC, might be a safer option. In prior studies, they found that far-UVC light killed methicillin-resistant S. aureus (MRSA) bacteria — a common and dangerous “superbug” — without harming human or mouse skin. In this new study, they found that far-UVC light also killed airborne H1N1 virus, a common strain of flu virus. “Far-UVC light has a very limited range and cannot penetrate through the outer dead-cell layer of human skin or the tear layer in the eye, so it’s not a human health hazard,” said Brenner, who directs Columbia’s Center for Radiological Research. However, “because viruses and bacteria are much smaller than human cells, far-UVC light can reach their DNA and kill them,” he said in a university news release. Lamps with this type of UV light currently cost less than $1,000, Brenner said, but that price would likely fall if the lamps were mass-produced. “And unlike flu vaccines, far-UVC is likely to be effective against all airborne microbes, even newly emerging strains,” he said. Two flu experts were encouraged by the findings. “The prospect of reducing the transmission of influenza and other respiratory viruses using far-UV radiation is very exciting,” said Dr. Michael Grosso, chief medical officer at Huntington Hospital in Huntington, N.Y. “Though hand-washing remains critically important, it does not prevent every instance of transmission,” Grosso said. “Immunization and antiviral medications are also important, but again, have limitations. It appears that low-dose far-UV light is safe and effective, and has the advantage of inactivating a wide range of disease-causing viruses.” Dr. Len Horovitz, a pulmonary specialist at Lenox Hill Hospital in New York City, agreed. He noted that the technology’s cost “is not prohibitive, and it is safe. This use can sterilize the air in a public space, reducing the spread of respiratory droplets containing flu viruses and other bacteria and viruses.” The findings were published online Feb. 9 in the journal Scientific Reports. More information The U.S. Centers for Disease Control and Prevention has more on flu.
12 January 2018
FRIDAY, Jan. 12, 2018 (HealthDay News) — With a severe flu season now widespread across 46 states, do symptoms you or a loved one have point to the dreaded illness? Amid the sniffles, coughing and fever, “it’s sometimes difficult to determine whether you have the common cold or the flu,” said Dr. Boris Khodorkovsky. He’s associate chair of emergency medicine at Staten Island University Hospital in New York City. But it’s an important question, he said, because while colds and flu share some symptoms, flu can become severe enough to land you in the hospital. Certain symptoms — runny nose, congestion, sneezing, minor body aches and fever — are common to both maladies. But “your alarm should go off when you start experiencing high fever and chills” — that’s most probably the flu, Khodorkovsky said. He said “high fever” is typically thought of in this context as 101 degrees or above, but lower fevers can sometimes occur in otherwise severe flu. Dr. Len Horovitz, an emergency physician at New York City’s Lenox Hill Hospital, agreed. He added that one thing to watch for is how quickly the illness escalates. “The common cold can come on slowly — sore throat, sneezing, cough, fever — while the flu is rapid in onset,” Horovitz said. “The onset of flu is also often “accompanied by severe body aches, weakness and sometimes skin sensitivity,” he added. If it is influenza, the standard advice applies, Khodorkovsky said. “It’s important to take fever-reducing medications, stay at home and away from other family members as best possible, rest, and most importantly — hydrate.” Hydration can be with plain water or with broth, which helps nourish the body, too. That old standby, chicken soup, can work wonders. “There’s research that suggests chicken soup can inhibit mucus production that will help alleviate a runny nose and cough,” Khodorkovsky said. “Sports drinks, preferably diluted with some water, will also replenish vital electrolytes and sugars,” he added. And medicines may help shorten the ordeal, Horovitz said. “The flu can be treated with Tamiflu if started within 48 hours of presentation,” he said, while zinc supplements may help ease the common cold. Of course, not every case of flu ebbs away on its own at home, and this U.S. flu season is already seeing a big spike in hospitalizations. “If your symptoms persist and escalate, seek medical attention immediately,” Khodorkovsky said. “Influenza can lead to respiratory complications like pneumonia, to even something more fatal.” Your best defense against colds and flu? Not getting one in the first place. Hand washing is key, Khodorkovsky said. “Flu travels via droplets in the air, but also can live on surfaces for up to 24 hours,” he pointed out. “Think of all of the door knobs and handles you grab and hands you shake each day. I recommend washing your hands every one to two hours during this season. And Horovitz added that this means only touching your face, mouth or other people if you know you’ve just washed your hands. “Additionally, it’s never too late in the season to get the flu shot,” Khodorkovsky said. “It’s not a 100 percent guarantee, but [it] will protect you from the deadlier strains of the virus.” More information There’s more on seasonal flu at the U.S. Centers for Disease Control and Prevention.