Recurrent ear infections are more common in white kids, especially those from poor background, says a new US study.

White children and those in poor families are more likely to have repeated ear infections than other children, U.S. researchers have found.

Researchers from the University of California, Los Angeles (UCLA) and Harvard University studied data from the U.S. National Health Interview Survey during the period 1997-2006 for the analysis. They found that the rate of frequent ear infections at 7 percent was the highest for white children.

Meanwhile, the rates of infections were 6.2 percent for Hispanic children, 5 percent for black children, and 4.5 percent for children of other racial or ethnic groups. The average age of the children in the study was 8.5 years.

Also, the rate of frequent ear infections among children in households below the poverty line was higher (8 percent) than that for those in families above the poverty line.

"The racial and ethnic disparity was somewhat surprising," study co-author Dr. Nina Shapiro, director of paediatric otolaryngology at Mattel Children's Hospital UCLA, said in a UCLA news release.

"We are not certain why these gaps exist, but possible explanations could include anatomic differences, cultural factors or disparate access to health care. It could also be that white children are over diagnosed and non-white children are under diagnosed," she said while publishing the findings in the August issue of the journal Laryngoscope.

Infection affecting the middle ear also called otitis media is one of the most common health problems in children. By the age of 3, more than 80 percent of children have had at least one ear infection.

As many as 4.65 million U.S. children suffer frequent ear infections each year, defined as more than three infections over 12 months, according to background information in the study by University of California, Los Angeles (UCLA) and Harvard University researchers.