A child in Fukushima Prefecture has been diagnosed with thyroid cancer in the latest health survey to assess the impact of the triple core meltdown that blanketed the region with radiation in 2011.

Seven others in the survey of 385,000 children in Fukushima Prefecture are also suspected of having thyroid cancer but have not received a definitive diagnosis, a prefectural committee said. The survey began in April 2014, three years after the Great East Japan Earthquake and tsunami crippled Tepco's Fukushima No. 1 power plant.

The child diagnosed and the seven others tested negative in the first survey, which covered all 370,000 children in the prefecture who were 18 or younger at the time of the disaster. Those born a year after the meltdowns were not included.

"Despite the new results, I don't think we need to change our previous view" that they were not affected by the radiation, said Hokuto Hoshi, who heads the panel.

In the first survey, 86 children were confirmed as having thyroid cancer and 23 were suspected of having it.

In both surveys, the thyroid glands were first scanned with ultrasound to measure the size and shape of any lumps, and assigned four grades of severity. Those children assigned the two highest grades were then given blood tests and cell biopsies.

The child confirmed to have thyroid cancer and the seven suspected of having it were between 6 and 17 at the time of the accident, according to Fukushima Medical University, which conducted the survey.