San Francisco Chronicle - (Sunday)
Boy’s death baffles doctors
Virus often associated with common cold kills Milpitas 9yearold
Nineyearold Tristan Ang was a healthy soontobe fourthgrader when he fell ill a month ago, first with what seemed to be a mild summer bug, then with more worrisome symptoms: confusion, forgetfulness, a bad headache.
Six days later, he died in the intensive care unit of a hospital near his home in Milpitas. The cause, doctors told his parents, appeared to be a brain infection from a virus most often associated with the common cold. In Tristan’s case, for reasons no one understands, it was fatal.
“I don’t know why this happened to him. It was just this freak accident,” said Mark Ang, Tristan’s father. “It could be that God really wanted him up there.”
Just before he died on June 28, Tristan tested positive for adenovirus, which is actually a family of viruses made up of more than 50 strains. It’s not clear what strain Tristan was infected with.
Adenoviruses typically cause symptoms like sore throat, runny nose and cough. Up to 10% of colds are thought to be caused by adenoviruses. They are the most common cause of conjunctivitis, also known as pink eye. Some strains cause diarrhea.
Almost all children have been infected with at least one strain of adenovirus by the time they’re Tristan’s age.
“These are normal childhood infections — it’s almost shocking when you see somebody die from this.” Dr. Yvonne Maldonado, chief of pediatric infectious diseases at Stanford
Infection casts immunity on the individual for that particular strain of the virus, but because there are so many other strains, people can get sick with adenoviruses many times over.
Some strains are known to cause much more severe illness, including pneumonia and, rarely, meningitis or encephalitis — infections in the brain or spinal cord. But fatal cases are almost always in people with weakened immune systems — for example, organ transplant recipients — and even then, it’s unusual to die from an adenovirus.
“These are normal childhood infections — it’s almost shocking when you see somebody die from this,” said Dr. Yvonne Maldonado, chief of pediatric infectious diseases at Stanford. Maldonado was not familiar with details about Tristan’s case.
It’s not known how many people die from adenoviruses each year because the virus can’t always be found in the blood, tissue or spinal fluid. Last year, at least six children died from adenovirus infection during an outbreak at a rehabilitation center in New Jersey. The children all had compromised immune systems and had been infected by a strain of adenovirus known to be among the more severe.
Adenoviruses are contagious, but they generally require close contact to be passed from one person to another. Outbreaks can occur in settings like day care centers, college dormitories and military barracks. One large outbreak occurred in 1997 at a U.S. Navy training facility — 541 healthy young adults were infected then, most with adenovirusassociated pneumonia.
In fact, as far back as the 1950s, adenoviruses were reported to cause outbreaks among people in the military. A vaccine for two particularly virulent strains was developed in the early 1970s, and for several decades the military routinely gave it to recruits. But the sole manufacturer of the vaccine stopped making it in the mid1990s, and the military ended its immunization program. A small supply of the vaccine still exists, but it is only available to people in the military.
And generally, people shouldn’t think about being vaccinated for adenoviruses because they so rarely cause serious illness, infectious disease experts said.
“We can’t really vaccinate the entire population for an extremely rare disease, which this is with respect to it causing severe illness,” said Dr. Charles Chiu, director of the UCSFAbbott Viral Diagnostics and Discovery Center.
Chiu said the unusual death of a healthy child from an adenovirus should bring a public health investigation. Officials may monitor people who were in close contact with the child for signs of illness, especially if the strain involved was a particularly virulent one. Mark Ang said no one else in the family has been sick.
The Santa Clara County Department of Public Health would not say whether any adenovirus cases currently are being investigated and would not comment on Tristan’s death. A spokesman said the county looks into all reports of meningitis or encephalitis; there were 53 such cases last year, caused by a variety of infectious agents including viruses and bacteria.
Chiu — who was not involved with Tristan’s care — said there are several reasons why an ordinarily tame virus could kill a seemingly healthy child. A child could have an underlying immune disorder that has not been detected before. He could be infected with another pathogen that leaves him vulnerable to serious illness from the adenovirus.
Or he could be infected with a strain of virus that has mutated, making it more aggressive. That’s part of the reason a public health investigation is important, Chiu said. A spontaneous mutation of the virus is not likely, but also not unheard of. In 2012, Chiu investigated an outbreak of adenovirus in laboratory monkeys at UC Davis, in which the virus suddenly developed the ability to pass between animals and humans. A veterinarian and one other person became infected with the new strain, which fortunately caused mild illness in humans. It killed about 80% of the infected monkeys, though.
There is no specific treatment for infection with adenoviruses, even the more serious strains. An antiviral drug exists, but it’s not clear if it helps, and it comes with serious side effects, Maldonado said.
People can prevent spread of illness by regularly washing their hands and avoiding contact with others who are known to be sick, said Dr. Darvin Scott Smith, an infectious disease specialist at Kaiser Permanente Redwood City. Anyone with symptoms like cough, fever, runny nose, sore throat and itchy, inflamed eyes should stay home instead of going to work or school.
But for the most part, adenoviruses are going to circulate, and there is not much that can stop them.
“I don’t know what the bottom line is apart from washing hands. And that goes a long way, but there are limits to what you can do,” Smith said.
Tristan’s parents, who are both nurses, have been replaying the events that led to his death over the past few weeks, trying to understand what happened and if there was anything more they could have done. There wasn’t, Mark Ang said. He knows that, yet he can’t stop asking the question.
He and his wife, Belle Ang, tried for 14 years to get pregnant before Tristan was born. They ended up having two more children, but Tristan was the one their lives revolved around, Ang said. He was nationally competitive in tae kwon do — he was scheduled to participate in a tournament in Minnesota this month — and his training set the family’s schedule.
But he was also the heart of the family emotionally, Ang said.
“He would just hug you out of nowhere, kiss you, tell you he loved you,” Ang said. “He was such a goodhearted kid. I know he would have helped a ton of people.
“I hope other people can draw something from what’s happened to us, even if it’s just, love your kids. Hold them close, because you can lose them so fast.”