Photo taken on Jan 22, 2020 shows an exterior view of the headquarters of the World Health Organization (WHO) in Geneva, Switzerland. (LIU QU/XINHUA)

GENEVA - The World Health Organization (WHO) highlighted the importance to investigate early COVID-19 cases in different countries in a report released on Tuesday.

The WHO also said COVID-19 introduction through an intermediary host was considered to be "likely to very likely"

Experts from the WHO and China "reviewed data from published studies from different countries suggesting early circulation" of COVID-19, according to the report.

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The findings showed that "some of the suspected positive samples were detected even earlier than the first case in Wuhan, suggesting the possibility of missed circulation in other countries," reads the report.

"It is important to investigate these potential early events," according to the report.

The WHO also said in the report that COVID-19 introduction through an intermediary host was considered to be "likely to very likely."

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