Story highlights A man in England is infected with a form of the bacteria that is completely resistant to the first line of treatment

Gonorrhea has been a growing concern as the bacteria adapt

(CNN) Public Health England is investigating the case of a UK man infected with a multidrug-resistant form of gonorrhea.

The man attended sexual health services this year and was found to be infected with a form of the bacteria that is completely resistant to the first line of treatment used against it.

First-line treatment for gonorrhea is a combination of two antibiotics (azithromycin and ceftriaxone), and this is the first global report of an infection with high-level resistance to both drugs, according to Public Health England.

The man caught the sexually transmitted infection in Southeast Asia one month before his symptoms began, the case report states.

His infection is "is very resistant to the recommended first-line treatment," said Dr. Gwenda Hughes, consultant scientist and head of the sexually transmitted infection section at Public Health England. "This is the first time a case has displayed such high-level resistance to both of these drugs and to most other commonly used antibiotics."

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