Tests in mice and humans suggest too much salt can dampen the body's response to infection. A healthy diet, sleep, exercise and reducing stress may help the immune system function.
As people get older, their innate and adaptive immune responses develops a lower "attention span" so fails to respond to a virus as quickly, allowing it to get the upper hand.
The new virus has killed over 213 people in almost 10,000 cases.
The study provides more proof that children should be vaccinated against the virus, experts stressed.
The research suggests the immune system could be stronger in older age than previously thought.
Mosquito saliva may be increasing the severity of diseases.
Cancer experts expressed hope after learning that former President Jimmy Carter's melanoma would be treated with Merck & Co's Keytruda drug.
The tool is expected to help doctors find hard-to-detect infections in time to stop them in their tracks.
Chad Hayes on why he allowed his baby to be given all the shots.