MANILA - Community transmission is driving the surge in coronavirus infections in Navotas City, Mayor Toby Tiangco said Tuesday.

"That's what we discovered. There's a community transmission," he told TeleRadyo in Filipino.

On Monday, Navotas recorded an additional 51 COVID-19 infections, raising the tally of active cases to 358. The city has a total of 6,137 coronavirus cases, of which 5,586 recovered while 193 died.

The city government on Feb. 24 imposed granular lockdown at the city hall after several employees and their close contacts were found positive of the virus. The lockdown has been extended to March 9.

• Navotas City Hall on lockdown until Feb. 28: Mayor

Tiangco said they found out that some employees who didn't report to city hall have also caught the virus. Most members of their households also tested positive for COVID-19, he added.

"At first, we thought the transmission was happening in the city hall that's why it was ordered to be locked down," he said.

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Tiangco said they had sent the samples of the infected patients to the Philippine Genome Center for genome sequencing, which will determine the COVID-19 variant in the cases.

"Because we suspect it might be a new variant. Before, we also tested household members, the positivity rate is not that high. But now when one is positive, almost everyone gets infected," he said.

In January, Philippine health authorities confirmed the presence of the new and more transmissible coronavirus variant first reported in the United Kingdom.

• UK COVID-19 variant now in the Philippines, says DOH

On Tuesday, the Department of Health also reported the first 6 cases of the South Africa COVID-19 variant.

• Philippines detects first cases of South Africa COVID-19 variant