So far 169 cases of 'acute hepatitis of unknown origin' have been detected in 12 countries since last October, the World Health Organization (WHO) has announced.
The vast majority of cases have been among children age five and under, and so far one youngster has died and 17 have needed critical liver transplants.
Nine cases have been spotted in Alabama and two in North Carolina, however experts told DailyMail.com Monday they may be the 'tip of the iceberg', as many symptoms are missed.
Three-quarters of cases in the UK have been linked to adenoviruses, which usually cause the common cold. However, if someone's immune system is unable to fight off the virus, it can develop into hepatitis.
There are also fears that a strain of adenovirus may have mutated to become more severe.
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