Are Clues to Kawasaki Disease Blowing In the Wind?

Clues to the origins of a mysterious childhood disease may be blowing in the wind.

Kawasaki Disease is rare, and its characteristic prolonged fever is often mistaken for a mild viral infection. But it’s actually an inflammation of the blood vessels that can cause damage to the heart, sometimes despite treatment.

The cause of the disease, which strikes kids in Japan far more frequently than in other countries and is most often seen in the U.S. in Asian- and African-Americans, isn’t known. The thought is that there’s some genetic predisposition to KD, and then some environmental trigger that brings on the disease in susceptible kids.

Now a new study finds the ebb and flow of Kawasaki cases? is correlated with a wind that blows only at certain times of the year, starting in central Asia and heading south and east across Siberia, Korea and Japan before crossing the Pacific Ocean and hitting the U.S. west coast.

Jane Burns, an author of the new research and a professor of pediatrics and director of the Kawasaki Disease Research Center at U.C. San Diego and Rady Children’s Hospital-San Diego, tells the Health Blog the pattern seen in KD cases is unlike other diseases such as the flu. Cases mount during the late fall and first of the year, peaking in March, then ease off. There’s a second mini-peak during the summer and then the number of cases hits a nadir in September and October, she says.

She sees 15 to 17 new cases a month during peak season and only one to two during the trough.

The research, published in Nature Scientific Reports, shows a correlation between the wind patterns and the disease — when the wind heads east across Asia and to the U.S. west coast, cases mount, then decrease when the wind blows from the Pacific towards the north, in a westerly direction, Burns says.

Of course, this is only a correlation, and Burns is the first to say that the research can’t prove the winds are carrying any type of infectious agent or some type of pollutant that causes the disease. But research is pressing that question.

Ian Lipkin, a renowned “virus hunter” from Columbia University, is investigating the contents of dust sampled from the air high over Japan in March. “Once we get an idea of what the range of organisms is that’s in the wind, we’ll have a better idea of what we’re looking for,” says Burns.

But even without a known cause, pediatric hospitalists up and down the west coast are reporting cases of Kawasaki Disease to Scripps Institute of Oceanography. “The distribution, location and timing of cases will be analyzed with respect to wind patterns,” says Burns. If the winds can predict increased disease activity, alerts could go out to urgent care facilities and ERs to be on the lookout for possible cases, she says.

She says researchers haven’t identified other human pathogens that travel this way, but that African dust particles harboring a certain fungus are carried by winds all the way to the Caribbean, where the fungus causes disease in coral.

Image: Jane Burns/UCSD