It's difficult to look at current photos of 11-month-old Elijah for long. The baby boy contracted chicken pox, which covered his face and body in painful, blistering scabs and sores. As horrifying as these images are, they don't even show that he's also suffering from a secondary infection brought on by the virus.

So, how did this happen?

According to Kayley Burke, the baby's mother, it's simple: because people don't vaccinate their children.

"Our poor baby boy is too young to be immunized," she wrote in a heart-wrenching Facebook post. "Vaccinate your kids, people . . . Think about the risk you are putting on other helpless kids who are too young or who actually can't be vaccinated!"

A baby as young as Elijah getting chicken pox, also known as varicella, is certainly uncommon. According to the American Academy of Pediatrics, most babies receive antibodies against the virus from their mothers while in the womb that protect them in their first year of life – before they are old enough to get the vaccine at around 12 to 15 months of age.

However, because chicken pox is so contagious and can be passed from person to person — particularly between those who've gone unvaccinated — with remarkable ease, it's possible for babies to get a mild case. In rare cases, even healthy babies and children can develop serious complications, including pneumonia, encephalitis, brain swelling, or a bacterial skin infection.

Meanwhile, the varicella vaccine is proven to prevent severe illness in almost all children and is 85 percent effective in preventing even mild illness.

As for Elijah, not only was he admitted to the hospital after a week of agony, but Kayley and her 3-year-old daughter also contracted the viral illness.

"Adult chicken pox is so horrible and painful, I would much rather give birth with no pain relief," she wrote. "Bottom line, if you don't vaccinate your kids, you're a bloody idiot."