Landon Lewis, 4, was living in a Minneapolis homeless shelter when he fell ill, first with a fever of 104 degrees, then with a red rash on his forehead.
It took two visits to a doctor to diagnose a disease clinic staff hadn't seen in years: measles.
The rash spread into his mouth and throat, so swallowing was torture. He began vomiting and developed a cough that nearly choked him. He was rushed to the emergency room and hospitalized for five days.
"Seeing a child in that predicament really hurt," says his mother, Katrina Lewis, 27. "He can't eat, he can't sleep, he's bad all around, and you can't do anything about it."
Landon is one of at least 152 cases of measles diagnosed in the USA so far this year twice the number seen in a typical year and the biggest outbreak in 15 years, says the Centers for Disease Control and Prevention. Half of patients have had to be hospitalized.
For the doctors and nurses caring for patients like Landon, the return of vaccine-preventable diseases such as measles a viral illness that once killed 3,000 to 5,000 Americans a year is both frightening and all too predictable.
"Measles can be like a canary in a coal mine," says the CDC's Gregory Wallace. "If there are any issues with vaccine coverage, it can first be apparent with measles."
In the past three years, doctors also have seen outbreaks of other vaccine-preventable diseases, such as mumps, whooping cough and a life-threatening bacterial infection called Hib. All can be deadly.
Although overall vaccine coverage remains high, 40% of parents say they have deliberately skipped or delayed a shot for their children.
In some ways, vaccines are a victim of their own success. Today's parents have never seen the diseases that terrified their grandparents, says Paul Offit, chief of infectious disease at Children's Hospital of Philadelphia. "We've not only eliminated these diseases; we've eliminated the memory of these diseases," Offit says.
Parents who decline vaccines may not realize that they're gambling with the lives of not just their kids, but all the children around them, says Patsy Stinchfield, director of pediatric infectious disease at Children's Hospitals and Clinics of Minnesota, where Landon was treated. Measles can kill by causing pneumonia, brain inflammation and other complications, Stinchfield says. Babies too young to be vaccinated and people with compromised immune systems, such as those with cancer, are especially vulnerable. They rely on others around them to keep the virus out of circulation, a phenomenon known as "herd immunity," which protects even those who can't be vaccinated, she says.
And Offit notes that measles which killed 3,000 to 5,000 Americans a year in the pre-vaccine days continues to kill. More than 164,000 people died of the disease in 2008, the World Health Organization says.
In January, Erica Finkelstein-Parker lost her daughter, Emmalee, 8, to long-term neurological complications of measles. Emmalee got measles in an orphanage in India before being adopted and brought to the USA.
"This is not just a personal choice, a case of 'I choose not to vaccinate my child, and this only affects my family,'" says Finkelstein-Parker, of Littleston, Pa. "It affects your whole community."
Vaccines are widely available across the country, doctors say, and poor children can get them for free. The biggest impediment to vaccinating kids today is not cost, but fear, says William Schaffner, a spokesman for the Infectious Disease Society of America and professor at Vanderbilt University School of Medicine in Nashville. Around the world, millions of parents began skipping or delaying vaccines because of an infamous (and since retracted) 1998 study in the British medical journal The Lancet. The study's author theorized that a combined measles-mumps-rubella shot caused autism.
It became one of the greatest myths in modern medicine, says Offit, author of Deadly Choices: How the Anti-Vaccine Movement Threatens Us All. He points to nearly two dozen studies showing no link between vaccines and autism. Last year, The Lancet issued the retraction after learning that information had been falsified. British health officials also stripped the study's author of his ability to practice medicine in England because of professional misconduct.
Still, myths about vaccines and autism persist.
"It's very easy in our media-driven, easy-access-to-information society to scare people," says Tanya Remer Altmann, a doctor and spokeswoman for the American Academy of Pediatrics. "It's much more difficult to unscare them."
In the USA, one of the most influential voices on vaccines is pediatrician Robert Sears, author of The Vaccine Book, who developed an "alternative" vaccine schedule that delays many shots. Sears says infectious diseases remain a minor threat. "I'm not a proponent of mandatory vaccination" for schoolchildren, says Sears, the son of well-known pediatrician William Sears. "Overall, in my mind, vaccines should be a parent's choice. Given that these diseases don't pose a large threat to children around us, I think parents have that right."
More parents are exercising their rights to refuse vaccines, research shows. Forty-nine states allow children to bypass school vaccination requirements because of religious objections, and 21 allow philosophical exemptions, Offit says.
From 1991 to 2004, the number of unvaccinated children in states allowing philosophical exemptions more than doubled, found a study in Journal of the American Medical Association. Granting exceptions to vaccine requirements has helped foster outbreaks, research shows. That's partly because like-minded parents tend to flock together, creating enclaves in which relatively few children are vaccinated on time and viruses have more freedom to spread, says Ari Brown of the American Academy of Pediatrics.
In some counties in Washington state, for example, up to one in four children are exempt from vaccine requirements, according to a 2009 study in The New England Journal of Medicine. One of these under-vaccinated communities, Vashon Island, near Seattle, has been hit with repeated outbreaks of whooping cough, Offit says. Schaffner notes that France, which doesn't strictly enforce school vaccine policies, has had more than 10,000 measles cases and six deaths just this year.
A growing number of unvaccinated travelers are bringing the disease home, the CDC says. And as the summer travel season launches into full swing, "these viral diseases are only a plane ride away," says Schaffner. Cancer survivor Catherine Anderson, 41, contracted measles in March from a fellow passenger on a flight from New York to Vancouver, British Columbia. In spite of having had measles as a child, Anderson got sick because migraine medications suppress her immune system. She was quarantined in her home for a week. "The airline called me," she says, "just as I was starting to wonder, 'Hmm, I wonder what that red rash is?'"
Among the most vulnerable patients are children with cancer, including Ben Bredesen, 3, who has acute leukemia. He was exposed to measles in March by another child at the Minneapolis hospital where he receives chemotherapy, says his mother, Laura Bredesen of Minneapolis. "I can't tell you how much weight I lost, how sick you feel, checking your child at night to make sure he's still breathing," says Bredesen, noting that infections such as measles could kill her son. "You're looking at every little thing as a symptom."
Ben was lucky this time and didn't develop measles. But he will remain vulnerable during the two years of cancer therapy ahead. "My kid is fighting for his life every single day," Bredesen says. "There is no reason that he should have to fight even harder because other people aren't vaccinating their kids."
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