Unvaccinated woman, 90, died with double variant infection, European researchers say

A 90-year-old unvaccinated woman who died after contracting the coronavirus this spring in Europe was found to have been infected with two variants simultaneously. 

Her case was presented and discussed this weekend at the European Congress on Clinical Microbiology & Infectious Diseases (ECCMID) as part of Belgian research.

The woman went to the hospital after a series of falls and also tested positive for COVID-19, according to the European Society of Clinical Microbiology and Infectious Diseases

When she was admitted to the hospital, she was in good health and did not show signs of respiratory distress. However, her health began to decline rapidly and she died five days later. 

After her death, researchers discovered she had been infected by two different strains of the virus - the UK strain and the South African strain. They ran her initial test to look for variants of concern with PCR testing.

Researchers believe it’s the first documented case of its kind and, although rare, that similar dual infections are happening around the world. 

"Up to now, there have been no other published cases. However, the global occurrence of this phenomenon is probably underestimated due to limited testing for variants of concern and the lack of a simple way to identify co-infections with whole genome sequencing," said lead author and molecular biologist Dr. Anne Vankeerberghen from the OLV Hospital in Aalst, Belgium, where the patient received care. 

"Both these variants were circulating in Belgium at the time, so it is likely that the lady was co-infected with different viruses from two different people. Unfortunately, we don't know how she became infected," she added. 

Both the UK and South African strains, known as the alpha and beta strains respectively, are also circulating in the United States.

They’re two of the four variants of concern in the country right now, as designated by the U.S. Centers for Disease Control and Prevention. 

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The other two variants of concern in the U.S. currently are the delta variant, first identified in India, and the gamma variant, first identified in Japan and Brazil. 

Earlier this week, the CDC predicted the delta variant has now become the dominant strain of COVID-19 in the U.S. 

National genomic surveillance data showed the delta variant accounting for 30.4% of cases in the two-week period that ended on June 19. The CDC believes that will grow to 51.7% for the two-week period that ended July 3.

"And in some parts of the country, the percentage is even higher. For example, in parts of the Midwest and Upper Mountain states, CDC’s early sequence data suggests the delta variant accounts for approximately 80 percent of cases," said Dr. Rochelle Walensky, director of the CDC, on Thursday at a COVID-19 White House briefing.

It’s still unclear if the delta variant is more deadly than other strains, but the CDC notes "increased transmissibility" with the delta variant and the potential for it to make certain monoclonal antibody treatments less effective. 

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Even so, all three authorized vaccinations in the U.S. have been found to be effective against the COVID variants.

As of Sunday, the CDC says more than 67% of American adults have had at least one shot of their vaccination. Nearly 160 million Americans have been fully vaccinated.

This story was reported from Detroit.