Hong Kong — A fully vaccinated man in Hong Kong was found to be highly infectious after testing positive for the Delta variant of the Covid-19 virus.
The 27-year-old man got fully inoculated before his two-week trip to the United States. He returned on Jul 18 and tested positive for the virus.
Reports noted that his case came to light after the Centre for Health Protection revealed what happened to the man, which is something it doesn’t often do.
The man had a high viral load, indicating a large amount of the virus found in his upper respiratory tract and making him highly infectious.
His tests showed a viral load of about 21 and 24, where any number below 30 indicates a high degree of infectiousness, reported South China Morning Post on Monday (Aug 2).
It was also discovered that the man was infected with the highly transmissible L452R strain also present in the Delta variant.
Despite receiving two doses of the Pfizer BioNTech vaccine on Apr 26 and May 17 in Hong Kong, the centre noted that the man was likely infected in the US.
After his case was announced, authorities imposed an overnight lockdown at the block of his residence.
All 185 occupants in the area were tested, after which no other infections were confirmed.
In response to the incident, medical experts said there was no cause for alarm.
Professor David Hui Shu-cheong of Chinese University added that Hong Kong’s strict quarantine and contact-tracing protocols had prevented an outbreak thus far from the confirmed case.
Experts also noted that the man’s increased infectiousness was due to the Delta variant. They reiterated that vaccines help in minimizing severe symptoms of the virus.
Leading microbiologist and government pandemic adviser Professor Yuen Kwok-yung said that new information on the Delta variant shows it could lead to more vaccinated people spreading the virus without detection.
There is an increased risk of people not getting tested on the premise that they are vaccinated and cannot contract the virus, he noted.
Some young, fully vaccinated, and asymptomatic patients could also become hidden carriers if their infections continued undetected, said Prof Yuen.
Official city reports confirmed 30 individuals were infected with Coviid-19 despite being vaccinated.
The emergence of the Delta variant has changed the understanding of Covid-19 protection through vaccination, said Dr Leung Chi-chiu, a respiratory medicine specialist.
She said changes in biological characteristics of the variant increased its transmissibility, causing a higher viral load in those infected.
The Delta variant is reported to infect six to eight others after infecting a patient. Experts expect it to be the dominant strain globally. /TISG
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