MANILA (UPDATE 4) - The Department of Health on Friday said it has detected 16 new Delta variant cases in the Philippines, including the first local cases, based on the latest whole genome sequencing report.

Of the new cases, 5 were returning overseas Filipino workers.

One case arrived in the Philippines from the United Kingdom on April 26 and has been tagged as recovered after undergoing the 14-day quarantine period. Another two of these cases arrived in the Philippines from Qatar on June 15 and have recovered.

Eleven of the new Delta variant cases were local cases, Health spokesperson Undersecretary Maria Rosario Vergerie said in an online press conference.

Six Delta variant carriers are from Northern Mindanao, 2 are from the National Capital Region, another 2 from Western Visayas, and a lone patient is from Central Luzon, data from the DOH showed.

Of these 16 patients, 1 died while 15 others recovered, the DOH said.

"'Yung ating mga kaso dito ay paisa-isa sa bawat lugar. We call it sporadic," Vergeire said.

(There is only one case in an area. We call it sporadic.)

"We are further verifying, but most likely galing po talaga sa ibang bansa at nakapasok lang po sa ating borders (these really came from other countries and just slipped past our borders)," she said.

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The DOH said it is still investigating if the local cases have already led to local transmissions.

The term 'local transmission' is used if there is evidence that a local case has already transmitted the virus to another local case, DOH Epidemiology Bureau Dir. Alethea De Guzman said.

"It is sporadic in some of the areas. Ini-investigate pa natin kung may linkage na sila sa isa't isa at saan nila nakuha itong Delta variant na ito," she said.

(We are investigating if there are linkages among these cases and where they got this Delta variant.)

The Delta variant - which was first detected in India - is more contagious than the original COVID-19 strain due to the presence of the L452R mutation, which allows the virus to get past the immune system and spread faster in cells.

The DOH has instructed affected local government units to improve their contact tracing efforts and "do back tracing" among Delta variant carriers, Vergeire said.

"Kailangan ma-expand natin 'yung pagtrace ng contacts up to the third generation ng contacts para makita natin sino ang apektado," she said.

(We need to expand contact tracing up to the third generation of contacts to see who really is affected.)

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ONE DELTA VARIANT CARRIER FULLY VACCINATED VS COVID-19

One of the Delta variant carriers was already fully vaccinated against COVID-19, De Guzman said, without saying the brand of the vaccine.

The fully vaccinated Delta variant carrier only developed a "mild case" of COVID-19, she said.

"The others have not yet been vaccinated and we have 2 other cases na kino-confirm nating kung nabakunahan na o hindi (that are being confirmed if they have been vaccinated or not)," she said.

One Delta variant carrier is a 14-year-old, while another is an 18-year-old, she said.

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While existing COVID-19 vaccines could not fully protect individuals from the Delta variant, the jabs still provide protection to avoid developing severe cases or COVID-19, said Dr. Edsel Salvaña, an infectious disease expert who also advises the government on COVID-19.

"Kapag nag-mutate 'yung spike protein, bumababa ang bisa niyan... Sa Israel, kahit yung Pfizer, 64 percent effective na lang [against the Delta variant]," he said.

(The mutation of the spike protein reduces the efficacy of vaccines... In Israel even Pfizer's efficacy was reduced to 64 percent.)

Vaccines usually contain various components of a virus to alert the body to produce more antibodies against a foreign pathogen, he said.

While mutations could weaken the response of antibodies, cytotoxic T-cells - another component of vaccines - could still "protect you from infection," he said.

"Napakababa pa rin ng lebel ng mga taong namamatay dahil kahit hindi gumagana 'yung antibodies, gumagana pa rin yung t-cells," he said.

(The level of deaths due to COVID-19 remain low because even if the antibodies are no longer working, the t-cells are still in effect.)

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Vaccine czar Carlito Galvez said the national government will reallocate more vaccines to regions where the Delta varian was detected, particularly in Northern Mindanao.

The DOH said the increase of Delta variant carriers in the Philippines has yet to affect the in number of COVID-19 cases in the country.

"Sa ngayon, may bahagyang pagtaas sa iilang lugar pero hindi pa ganun kataas kaya nasasabi natin na possible na sporadic pa lamang ito," De Guzman said.

(As of now, there is a small increase of cases in some areas but it is not that significant that's why we say that it is possible that these cases are just sporadic.)

"Ito 'yung opportunity natin na ma-contain pa natin yung further spread," she said.

(This is our opportunity to contain the further spread of the variants.)

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The DOH urged the public not to attend small gatherings now that more cases of the Delta variant have been recorded in the country.

"Now that we have a more transmissible variant circulating locally, we need to make sure no mass gatherings are held, even small social gatherings within families and health groups," said Dr. Anna Ong Lim, who is part of the DOH's technical advisory group.

"We should rethink these because this could be potential super spreader events," she said.

In July, the Philippines recorded 19 other Delta variant carriers in the country.

The Philippines has issued a travel ban against Indonesia, where some 54,000 people contract COVID-19 daily due to the Delta variant.

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