First Choice Neurology

Booster Needed for Delta and Lambda Variants

Scientists may have underestimated the coronavirus. In the beginning, they said mutated versions shouldn’t be much of a problem—until Alpha spiked last fall. Then, Beta made young people sicker. And Gamma reinfected people. Some epidemiologists were cautiously optimistic that the rapid vaccine rollout would tame the variants… until the Delta variant appeared.

Covid-19 VariantsDelta was first identified in India in December and spreads faster than any previous strain of the coronavirus. Delta, more than any other variant, has reset scientists’ understanding of how quickly a virus can evolve into devastating new forms. It is driving up infection rates in every state of the U.S. and remains the dominant strain.

Newsweek wrote, The Delta outbreak is going to get much worse, warns Michael Osterholm, an epidemiologist who leads the Center for Infectious Disease Research and Policy at the University of Minnesota. “The number of intensive-care beds needed could be higher than any time we’ve seen,” he says. He adds that his team’s analysis shows that almost every single one of the 100 million unvaccinated Americans who hasn’t had COVID-19 yet will likely get it in the coming months, short of taking the sort of strong isolation and masking precautions that seem unlikely in the vaccine-hesitant population.

Like the Delta variant, Lambda is highly infectious and shows signs of having unusual success in infecting fully vaccinated people, according to one early study. There have also been some alarming characteristics detected by researchers. It’s too soon to say whether Lambda will turn out to be the next big thing that COVID-19 unleashes on us.

The World Health Organization (WHO) says Lambda has the potential for increased transmissibility. Lambda may also have increased resistance to neutralizing antibodies. WHO classified Lambda as a global variant of interest. Their definition for “variant of interest” allows Lambda to have the potential for disease severity. It has also been identified as causing significant community transmission.

Senior researcher Kei Sato of the University of Tokyo recently told Reuters that “Lambda can be a potential threat to the human society.”

The Centers for Disease Control and Prevention (CDC) does not include Lambda as being a variant of interest, concern, or high consequence. For now, most scientists will remain focused on the Delta variant. The CDC says that more than 90% of COVID cases in the U.S. are currently caused by the delta variant.

The WHO is still monitoring other variants — Eta, Kappa, and Iota. Any of these variants could develop into a threat.


How are Variants Labeled?

Variant of Interest – According to the CDC, a variant with specific genetic markers that have been associated with changes to receptor binding, reduced neutralization by antibodies generated against previous infection or vaccination, reduced efficacy of treatments, potential diagnostic impact, or predicted increase in transmissibility or disease severity. Recently selected characteristics of SARS-CoV-2 “variants of interest” include Eta, Iota, Kappa, and None.

Variant of Concern – A variant for which there is evidence of an increase in transmissibility, more severe disease (e.g., increased hospitalizations or deaths), a significant reduction in neutralization by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures. Today, selected characteristics of SARS-CoV-2 “variants of concern” include Alpha, Beta, Delta, and Gamma.

Variant of High Consequence – A variant of high consequence has clear evidence that prevention measures or medical countermeasures (MCMs) have significantly reduced effectiveness relative to previously circulating variants. Currently, there are no SARS-CoV-2 “variants of high consequence”.


New Variants and Vaccines

If you are fully vaccinated, you still have a high degree of protection from the worst outcomes of Covid-19 — severe disease, hospitalization, and death. The CDC estimates vaccines are 93%-100% effective in preventing hospitalizations even with the Delta variant. This prevents the health care system from becoming overwhelmed.

Covid-19 VaccinesResearch studies show vaccines protect against coronavirus strains, including Delta and some researchers believe Lambda too. But there hasn’t been sufficient data regarding how effective current vaccines are against preventing infection from Lambda.

Data shows that vaccinated people who still get infected with the Delta variant also have high viral loads and can spread it to others, even when they aren’t showing symptoms.

On Monday, Israel released new data showing a reduction in the effectiveness of Pfizer’s Covid vaccine against severe illness among people 65 and older who were fully vaccinated in January or February.

Tuesday, National Institutes of Health (NIH) Director Dr. Francis Collins said that data Israel released is causing U.S. health leaders to rethink their position on vaccine booster shots in the U.S.

Today, U.S. health officials strongly recommended booster shots for those who received the Pfizer and Moderna vaccines eight months after receiving their second doses, starting September 20. First in line will be health care workers, nursing home residents, and other older adults, followed by the rest of the general population.

Dr. Rochelle Walensky, director of the CDC, cited one study that suggests that vaccine efficacy against the Delta variant decreased regardless of when people were inoculated. She also added that the latest data “confirms that protection against infection may decrease over time, protection against severe disease and hospitalization is currently holding up pretty well.”

Dr. Anthony Fauci, an infectious disease expert at the National Institutes of Health (NIH), said studies show that third shots of the Moderna and Pfizer vaccines can boost the levels of antibodies that fight the virus ten-fold, an increase he called “dramatic.”

WebMD wrote today that preliminary data from seven states suggests that breakthrough COVID-19 infections among vaccinated people may be on the rise due to the more contagious Delta variant. Breakthrough cases accounted for about 1 in 5 newly diagnosed cases in six of the states, according to The New York Times. Hospitalizations and deaths among vaccinated people may be higher than previously thought as well.


How Do mRNA Vaccines Work?

According to the CDC’s website, Moderna and Pfizer’s mRNA vaccines are a new type of vaccine to protect against infectious diseases. To trigger an immune response, many vaccines put a weakened or inactivated germ into our bodies. Not mRNA vaccines. Instead, they teach our cells how to make a protein—or even just a piece of a protein—that triggers an immune response inside our bodies.

COVID-19 mRNA vaccines give instructions for our cells to make a harmless piece of what is called the “spike protein.” The spike protein is found on the surface of the virus that causes COVID-19.

First, COVID-19 mRNA vaccines are given in the upper arm muscle. Once the instructions (mRNA) are inside the muscle cells, the cells use them to make the protein piece. After the protein piece is made, the cell breaks down the instructions and gets rid of them.

Next, the cell displays the protein piece on its surface. Our immune systems recognize that the protein doesn’t belong there and begin building an immune response and making antibodies, like what happens in natural infection against COVID-19.

At the end of the process, our bodies have learned how to protect against future infections. The benefit of mRNA vaccines, like all vaccines, is those vaccinated gain this protection without ever having to risk the serious consequences of getting sick with COVID-19.


Where to Get Vaccinated in Florida

Florida has many sites that are providing COVID-19 vaccines. COVID-19 vaccines are safe, highly effective, and free. Appointments may be required, and specific vaccine types and brands may not be available at all sites. Visit to find a vaccine location.

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