Plague
Think this notorious killer died with the Middle Ages? The disease actually persists in parts of Africa, Asia, and South America. And there have been 16 reported cases of plague, with four deaths, in the United States this past year. Most recently, a 16-year-old girl from Oregon was sickened and hospitalized after apparently being bitten by a flea on a hunting trip. You can get plague from fleas that have carried the Yersinia pestis bacteria from an infected rodent, or by handling an infected animal, according to the Centers for Disease Control and Prevention (CDC). Bubonic plague is the most common form in the U.S., while pneumonic plague (affecting the lungs) and septicemic plague (affecting the blood) are less prevalent but more serious. Symptoms of bubonic plague include fever, chills, headache, and swollen lymph glands.
The good news is that plague is extremely rare, has a very low risk of person-to-person transmission, and can be effectively treated with antibiotics, explains Michael Phillips, MD, Associate Director of the Division of Infectious Diseases in the Department of Medicine at NYU Langone Medical Center. (The bad news is that plague can be fatal if treatment isn't started within 24 hours of the arrival of symptoms.) To stay safe, avoid contact with wild rodents (that means squirrels and chipmunks, in addition to rats), steer clear of dead critters, and call your doctor if you develop any symptoms after being exposed to fleas or rodents, particularly in western states, where U.S. cases tend to occur. "While we can expect to see occasional cases in parts of America, it's highly unlikely that there would be a wide-scale outbreak," says Dr. Phillips. "As long as you're not mucking around where you might come up against mice and fleas, you don't have to worry."
Mumps
Once a common illness among children and young adults, cases of mumps in the US have dropped by 99% since a vaccine was introduced in 1967. But occurrences crop up, particularly among close-knit communities. The CDC reports that there have been 688 reported cases of mumps in the US in 2015, including small outbreaks at universities in Pennsylvania, Iowa, and Wisconsin. In 2014, there was a mini-outbreak among professional hockey players. The virus that causes mumps is spread in close quarters (think college dorms or locker rooms) via coughing, sneezing, talking, or sharing cups or eating utensils. Symptoms of mumps include fatigue, fever, head and muscle aches, and loss of appetite, followed by puffy cheeks caused by swelling of the salivary glands. There is no treatment, but most people recover fully in a few weeks. Complications are rare, but can include hearing loss, meningitis, and inflammation of the testicles or ovaries.
The only way to prevent the mumps (aside from avoiding people with it) is to get the MMR (measles-mumps-rubella) vaccine. Though usually administered to kids, you can get the vaccine at any time. It's not foolproof (two doses are 88% effective at preventing the disease, per the CDC), and its protection can wear off over time, but it's vastly better to get the shot than not. Booster doses are often recommended during outbreaks.
Measles