A strain of COVID-19 first detected in India has been identified in Hawaii, the state Department of Health announced Monday.
Known as the Delta variant, the strain was identified in a specimen from an Oahu adult who traveled to Nevada in early May.
“This is not unexpected,” Dr. Edward Desmond, administrator of the State Laboratories division, said in a Zoom call with reporters. “This variant originated in India and has been found in the U.K. and was reported a month or more ago in California.”
The state Laboratories Division routinely monitors for variants through genome sequencing surveillance.
According to the DOH, the division began genome sequencing virus specimens in June 2020 and. It now examines 50 to 100 per week and has developed a testing algorithm to find variants in a timely manner.
Desmond said the Delta strain is a variant of concern because it “tends to become dominant,” which suggests it may be more transmissible.
The Delta variant now makes up approximately 6% of all COVID-19 cases in the United States, the DOH said.
According to the DOH, the individual was fully vaccinated against COVID-19 prior to travel and had a negative test before leaving Nevada. However, they developed mild symptoms several days after returning to Hawaii and subsequently tested positive for the virus.
The individual isolated and household and close contacts were quarantined, the department said.
Acting state epidemiologist Dr. Sarah Kemble said in the same Zoom call that it does not appear there was any further transmission from the single case.
“However, one of the things that’s of some concern was that the person was fully vaccinated, had two doses of an mRNA vaccine, so it is a vaccine breakthrough case and we do see those from time-to-time … ,” said Kemble. “I do think that many of the other household contacts being vaccinated also played a role in this not transmitting further. So we have an example here of why even though vaccine is not 100% every time, it’s still incredibly important and effective in slowing the spread of even these novel variants.”
Desmond said the Delta variant has some mutations found in other strains.
“There’s a reason why it was called the ‘double mutant’ initially,” he said. “It has two mutations which are associated with less effectiveness of antibodies, but a recent study … shows that when people have been vaccinated with either the Pfizer or the Moderna, they still have an effective antibody response to neutralize even this strain that has the two mutations.”
Kemble said there was concern initially when looking at “test tube” studies that antibodies would have a harder time neutralizing this strain of the coronavirus.
“However, in real world studies, when you actually look at people who have been fully vaccinated and compare them with people who are not who had this strain, it does look like the vaccines that are out there now are still quite effective against this strain if you’ve been fully vaccinated,” she said.
Kemble said there’s not currently compelling data to say whether the Delta variant causes more severe illness.
But any virus that is more transmissible will cause more cases, she said, “and the more cases you have the more hospitalizations and deaths you may have from those cases.
“So in that sense we always worry about something that is easily spread because it is more likely to cause those bad outcomes.”
According to Kemble, Hawaii has seen just over 170 break-through cases since vaccination efforts began in December.
According to Desmond, the B.1.1.7 variant, which was first found in the U.K., remains the most dominant COVID-19 strain statewide.
However, in Hawaii and Maui counties, the B.1.429 variant, which was first found in California, is “relatively more common” than it is on Oahu, he said.
“But the pattern, unfortunately, is that when the Delta strain is introduced, as it was in the United Kingdom, it has a tendency to become the dominant strain,” Desmond said. “Let’s hope that doesn’t happen here.”
Email Stephanie Salmons at ssalmons@hawaiitribune-herald.com.