Flu season is in full swing, and researchers across the country are keeping tabs on the virus' spread.

A universal flu vaccine to protect against all strains of the flu doesn't exist yet. But a new one does appear to protect against four flu strains at once.

Human cases of bird flu are no longer unheard of, but the latest case is especially catching the attention of global health officials — it's the first infection with a new strain.

Americans might get a flu vaccine to avoid getting sick, but they might not consider the large scale outcome of this decision — the millions of flu cases across the country avoided through vaccination.

Antibiotics completely revolutionized the way medicine is practiced. But they brought a downside too — when bacteria learned to fight back.

New guidelines for treating certain diseases are sometimes issued to save money and improve patients' care. But doctors may need an extra push to follow them.

Often, more care is not necessarily better care. For certain conditions, such as bronchiolitis in children, extra medications or other treatments may not help recovery.

While going without flu vaccination can mean risking an unpleasant few days of sickness for most, it can mean risking major illness and hospital time for those with certain conditions.

Nelson Mandela, the former President of South Africa, has died. He was 95.

Shortly after US health officials took the precaution of approving a vaccine for the H5N1 bird flu strain, another strain is causing concerns for a different nation.