The Covid-19 tracking commission on June 4 said a security guard at the US embassy in Phnom Penh had contracted the novel coronavirus, despite having received a second dose of the Pfizer-BioNTech shot two weeks ago.

Embassy spokesperson Chad Roedemeier confirmed the SARS-CoV-2 infection to The Post.

“The employee is in strict quarantine and getting appropriate medical attention,” he said. “The embassy is working closely with Cambodian health authorities to ensure we meet all government health requirements to prevent any further spread of Covid-19.”

Roedemeier declined to elaborate due to privacy concerns.

The World Health Organisation (WHO) has said that in some rare instances, people may still contract the pathogen even after full vaccination. The global UN health body urges vigilance at all times.

But at just two weeks after having received his second dose, the security guard may not have built up sufficient immunity to prevent infection.

The US Centers for Disease Control and Prevention (CDC) cautions that it usually takes the body two weeks after inoculation to develop an immunity against the coronavirus, but it could take longer.

“You are not fully vaccinated until two weeks after the second dose of a two-dose vaccine or two weeks after a one-dose vaccine,” it said.