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LOS ANGELES - Several mutations of the deadly novel coronavirus are drawing attention and causing serious concern among medical experts over their transmissibility, and a new study from Japanese researchers suggests that an already-circulating variant could penetrate the protection of current COVID-19 vaccines.
While the delta variant ravages much of the U.S., driving up cases and hospitalizations mostly among the unvaccinated, another variant known as lambda is devastating parts of South America, and scientists now worry it could neutralize or evade antibodies generated by vaccines.
In a not-yet-peer-reviewed study published on July 28 on bioRxiv by researchers in Japan, researchers said the lambda variant currently driving cases in 26 countries — including Chile, Peru, Argentina and Ecuador — is proving to contain as much viral material as the delta variant, thanks to a similar mutation.
In April 2021, authorities in Peru said 81% of the country’s COVID-19 cases were associated with the lambda variant.
Researchers noted in the bioRxiv study that the "vaccination rate in Chile is relatively high; the percentage of the people who received at least one dose of COVID-19 vaccine was [about] 60%."
But "nevertheless, a big COVID-19 surge has occurred in Chile in Spring 2021, suggesting that the lambda variant is proficient in escaping from the antiviral immunity elicited by vaccination," study authors warned.
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"In addition to increasing viral infectivity, the delta variant exhibits higher resistance to the vaccine-induced neutralization. Similarly, here we showed that the lambda variant equips not only increased infectivity but also resistance against antiviral immunity," study authors added.
A separate study published on July 7 and led by Chinese epidemiologist Jing Lu at the Guangdong Provincial Center for Disease Control and Prevention in Guangzhou, China found that the delta variant contains 1,000 times more viral material than that of the original novel coronavirus variant that infected much of the global population during the onset of the global pandemic last year.
Health officials from the World Health Organization said earlier this month not much is known about the projected impact of the lambda variant, but there is the potential of increased transmissibility or possible increased resistance to neutralizing antibodies compared to the original COVID-19 strain. Researchers said more studies are needed to understand the variant.
Early studies, including one from New York University published July 2, suggest lambda may be a bit resistant to antibodies produced by the mRNA vaccines from Pfizer-BioNTech and Moderna, but concluded it is not resistant enough "to cause a significant loss of protection against infection."
"So far we have seen no indication that the lambda variant is more aggressive," Jairo Mendez-Rico, a WHO virologist, told Deutsche Welle. "It is possible that it may exhibit higher infection rates, but we don't yet have enough reliable data to compare it to gamma or delta."
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WHO officials first officially identified the lambda variant, or C.37, on June 14, 2020, pointing to a case in Peru that was documented in December 2020.
The rise of these concerning variants that appear to evade the protection of the vaccines comes as breakthrough cases continue to rise among vaccinated individuals.
As of July 26, the CDC reported that 163 million Americans had been vaccinated for COVID-19. Out of those inoculations in the same timeframe, 6,587 Covid-19 breakthrough cases occurred that either resulted in hospitalization or death.
While hospitalizations and deaths from breakthrough cases appear to be extremely rare, the CDC is not currently tracking all breakthrough cases, leaving a huge gap of data that could allow medical experts to better understand the impact of breakthrough cases on the pandemic.
In an email to FOX TV Stations on Aug. 3, a CDC spokesperson said, "On May 1, 2021, CDC transitioned the national reporting system to focus on vaccine breakthrough cases in patients who were hospitalized or died. This shift will help maximize the quality of the data collected on cases of greatest clinical and public health importance."
Despite the emergence of breakthrough cases, the CDC said vaccines are still the most effective tool at fighting the spread of the disease and it is critical that all people who are eligible get vaccinated as contagious and potentially deadlier mutations of the virus continue to emerge and circulate.
RELATED: UK scientists say variant that can evade COVID-19 vaccines ‘almost certain’
The July study on the lambda variant’s ability to spread despite vaccine effectiveness came as scientists out of the United Kingdom warned weeks before that it is "almost certain" a new COVID-19 variant will emerge that will render current vaccines ineffective.
A U.K. advisory group published a research and analysis paper on the long-term evolution of COVID-19 on July 26. The paper explores several hypothetical, but highly likely, scenarios of what humanity can expect in the long-term from COVID-19 based on current trends and data.
Scientists wrote that since the eradication of the novel coronavirus is "unlikely," there are sure to be new variants that emerge and infect the population at large.
As cases continue to rise and demand for vaccinations wanes, medical experts worry it may take much longer than expected for the world to see an end to the COVID-19 pandemic.
In a Zoom webinar for Brown University, medical experts discussed the prevalence of new variants of the novel coronavirus and what it means for the world’s attempts to return to normalcy.
"I did not think that we’d be at a point where a third of American adults would basically look at the last year and a half, look at the fact that we have these incredible vaccines that are available and widely available, easy to get, free, and say ‘no thank you,’" said Dr. Ashish Jha, dean of Brown University’s School of Public Health.
Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Pennsylvania and a member of the FDA Vaccine Advisory Panel, said he’s amazed at how much of society appears to have returned to normal behaviors despite the pandemic being far from over. He said last year most people were "good about masks and social distancing," and now "there’s 40,000 people at a Phillies game and people are having weddings and birthday parties and we’re just getting together much more than we did last year."
Jha estimates that the U.S. could see a peak of the virus in late August and into September, followed by a decline that he thinks will vary from state to state.