Lancen Kendall, just 5 months old, is the latest victim of an outbreak of enterovirus D68 (also referred to as EV-D68) sweeping across the United States, reported AZfamily.com. Earlier this month, when he didn't wake from his afternoon nap, Kathleen and Kevin Kendall of Phoenix, Ariz., rushed their infant to Banner Thunderbird Medical Center. Five pain-filled days later, doctors declared Lancen brain dead.

First identified in California in 1962, symptoms of this form of non-polio enterovirus may include fever, runny nose, sneezing, cough, and muscle aches. However, these mild signs of illness may soon give way to severe wheezing and difficulty breathing.

Lancen is one of 24 children in Arizona who have tested positive for enterovirus. State officials are awaiting results to see whether a specific D68 strain killed the infant. A medical examiner determined Lancen's death was the result of complications of enterovirus coupled with rhinovirus (a common bug that causes a cold).

Before his nap, Lancen didn't show any signs or symptoms of illness, according to his parents, who do not understand how their baby could have picked up a deadly bug. While that cannot be answered, it is known that infected adults may not display symptoms.

"It's kind of terrifying that it literally came out nowhere," his mother told the local news service, adding, "The little kids don't leave the house unless we're going somewhere as a family.” His father noted, "He put up a pretty good fight.”

About EV-D68

The virus spreads from person to person when an infected person coughs, sneezes, or touches a surface that is then touched by others, instructs the Centers for Disease Control and Prevention.

While small numbers of this particular strain of enterovirus have been reported regularly to CDC since 1987, this year the number of people confirmed with an EV-D68 infection is much greater than in previous years. The latest count totals 825 people in 46 states and the District of Columbia becoming ill with the virus. In general, infants, children, and teenagers are most likely to get infected and become sick from enterovirus, including, the CDC believes, EV-D68. While adults may also become infected, they are more likely to show no symptoms or only mild symptoms. Generally, doctors treat the symptoms caused by the virus, as there is no specific treatment for people with this respiratory illness.

CDC expects that, as with other enteroviruses, EV-D68 infections will likely begin to decline by late fall. EV-D68 has been detected in samples from seven patients who died, however the CDC is investigating whether this virus is the direct cause of mortality.