Latest on COVID-19 Variants, Vaccines, and Boosters

September 30, 2021

This article was medically reviewed by Dr. Theodore Markou.

We are more than 18 months into the COVID-19 pandemic and our lives have fundamentally changed. It’s an everchanging landscape with new variants emerging, vaccination rates evolving, and additional dose or “booster” eligibility changing. And it appears that these issues will be part of our daily existence into the near future. So, we must keep updated on the latest happenings to stay protected and to ensure we can live the healthiest and safest lives possible. In this article, ID Care infectious disease expert Dr. Theodore Markou answers important questions about the latest news and happenings surrounding COVID-19.

Latest on US and NJ Vaccination Rates

Since the start of the COVID-19 pandemic, vaccination rates have varied from state-to-state. From the start of CDC vaccine dose tracking in mid-December 2020, doses peaked in the US in mid-April 2021 and then began to decline through mid-July, with a slight upswing and then leveling off through late-September 2021. The CDC reports that current vaccination rates show 55% of the U.S. population fully vaccinated and 64% having received at least one dose. For the most vulnerable population, adults 65 and older, the numbers are even higher at 83% fully vaccinated and 93% at least one dose (source: CDC data as of 9/23/21). This is encouraging news for the country.

In New Jersey, we have achieved phenomenal vaccination rates through September 2021, especially when compared to national rates. Currently over 63% of the state’s population are fully vaccinated and 71% have received at least one dose. The figures are even more impressive among the most vulnerable population, those 65 and above, at over 87% fully vaccinated and over 98% receiving one dose. So, we’re certainly moving in the right direction. Keep updated on vaccine progress at

Which COVID-19 Variants are Most Concerning?

While vaccination rates in NJ are relatively high, all viruses change and mutate, just like COVID-19 has done. However, the Delta variant has completely changed the game as it is the most prevalent and contagious out there. According to Dr. Markou, “The degree or viral load of COVID-19 (Delta) in an infected individual is quite impressive. This has led to it being two to two and a half times more contagious than the previous variants, which means previously, one person can infect 2 to 3 people, whereas now, we’re seeing 4 to 6 people infected. And, according to some studies, this Delta variant is also associated with a higher hospitalization rate in those who are unvaccinated. This variant may also double your risk for death if unvaccinated as well.”

Lambda and Mu are other variants being closely monitored by scientists and infectious disease doctors like those at ID Care. Both were identified in South America and have slowly crept into the US, with low levels in states like Texas, Florida, and Arizona. While there is only early data on these variants, findings will be reported once more conclusive. But Delta still poses the most significant health risk across the US at this time.

In terms of NJ communities, the Delta variant still poses the most risk at around 90% of cases statewide and 98% in North Jersey. “The NJ Department of Health (NJDOH) sequences samples from a random section of New Jersey weekly, and we get an idea of what variants are circulating. And right now, we’re seeing a whole lot of Delta,” reveals Dr. Markou.

What is a Breakthrough Infection?

Current COVID-19 vaccines do protect people against severe disease and death; however, no vaccine is 100% effective at preventing illness, especially with the higher viral load and contagious nature of the Delta variant. So, breakthrough COVID-19 cases are to be expected, especially given the degree of the virus that’s circulating. A breakthrough infection is classified as a fully vaccinated individual who contracts COVID-19.

Dr. Markou notes that most breakthrough infections usually present with mild symptoms or are asymptomatic among the fully vaccinated. That’s because your body has developed enough antibodies to protect you from severe disease. However, this is not the case for those unvaccinated as they are hit hardest by the disease and comprise most of the hospitalizations. “Think of the vaccine as a full suit of body armor,” he says. “Now you’re placed in a war zone. You’ll likely be hit by a bullet, however, your body armor will either deflect it, or you’ll have a very minor injury. If you’re unvaccinated, or you have no body armor, you’re more likely to be hit much harder.”

You can refer to the CDC for more information on breakthrough infections after being vaccinated.

What is the Status of FDA Approval for COVID-19 Vaccines?

There are three COVID-19 vaccines currently available in the United States; Pfizer-BioNTech, Moderna, and Johnson & Johnson. On August 23, 2021, only the Pfizer-BioNTech vaccine was granted full FDA approval for individuals 16 and older but is currently available for children

12 -15 under Emergency Use Authorization (EUA). The other two vaccines have submitted their data and are pending full FDA approval while still authorized for individuals 18 and over under EUA guidelines.

What is the Difference between EUA and FDA Approval for Vaccines?

When it became evident last year that COVID-19 was a highly infectious and life-threatening disease, the Food and Drug Administration (FDA) worked closely with scientists and vaccine manufacturers to gather and interpret data on the safety and effectiveness of the vaccines. Getting Emergency Use Authorization (EUA) is a lengthy, highly scientific process that requires a significant amount of clinical trial data for risk/benefit evaluation. The purpose of EUA is to provide more timely access to drugs, diagnostic tests, or other critical medical products in times of public health emergencies when no other adequate options are available.

Dr. Markou explains, “Full FDA approval is a long and more arduous process that reviews even more scientific data over a longer duration for the quality, safety, and effectiveness of a medical product. This is a complicated process and requires more time to review all the clinical data from studies done in 2020 and 2021. However, EUA authorization is also a very rigorous scientific process to validate the quality, safety and effectiveness of the vaccines made available to protect the lives of millions of people”.

How do the Vaccines Impact Pediatric Cases?

Children typically have more mild illness than adults with COVID-19, but studies show that pediatric cases have increased since Delta emerged. “The public health aspect of this cannot be overlooked,” says Dr. Markou. “If you ignore a large section of the population, then you’re giving this virus an open playground to mutate and develop more variants. Then you’re back to square one.”

The vaccine itself, including the dosage amount, is the same for everyone. Vaccination is estimated to have saved 15,000 cases of COVID-19, 400 hospitalizations, and 3 deaths in the pediatric population. The science is clear and shows that the benefits of vaccination among young people far outweigh any risks. Proactive preventive measures are key as children are back in school, socializing, attending events, and participating in sports – all of which can perpetuate spread of the virus. Vaccination for those 12 and older is yet another safety measure to protect children against this contagious virus.

Will a COVID-19 Vaccine Be Required Annually?

COVID-19 has likely become endemic, meaning it will be with us forever, like the flu. So, the best way to mitigate its impact is through vaccination which is expected (not confirmed) to be required annually. As with other vaccines, there will be a worldwide surveillance of the most prevalent and troubling variants out there, deploying an annual vaccine that targets these to mitigate the impact of the virus.

What is Recommended Timing Between a COVID-19 and Flu Vaccine?

Both COVID-19 and flu vaccines are easily accessible in the US and strongly recommended by ID Care infectious disease experts. Most large retail pharmacies administer COVID-19 as well as flu vaccines. Dr. Markou says, “Individuals can and should get both vaccines, but we recommend spacing them out two weeks apart, getting the COVID-19 vaccine first because COVID-19 is far more deadly than the flu.”

What are the Latest Guidelines on Vaccine Boosters?

While the Delta variant continues to spread, data suggests that vaccine immunity begins to wane over time. Although fully vaccinated individuals are still largely protected from severe illness and hospitalization, those who do not receive an additional dose – also known as a booster – are at higher risk for a breakthrough infection. A booster will serve to “jump-start” the immune system and provide additional protection.

However, as of late September 2021, the FDA has not yet approved the additional dose or vaccine booster for widespread use among the general public. While decisions are subject to change daily, FDA eligibility recommendations have now been issued for the Pfizer-BioNTech vaccine, pending a CDC advisory board vote. While trial data and real-world evidence are being studied, additional dose authorizations are pending for both J&J (single-shot) and Moderna (two-dose) vaccines.

For the two-dose Pfizer-BioNTech vaccine, the FDA has authorized a third dose for the following eligible populations who had their last shot at least 6 months prior:

  • People 65 and older
  • Adults 18-64 at risk for severe COVID-19 illness or complications, including smokers, those pregnant, or immunocompromised, as well as people who are overweight/obese, diabetic, have high blood pressure, substance abusers, transplant recipients, cancer patients, and those with other chronic medical conditions.
  • Adults 18-64 who have high job-related risk, like healthcare workers, teachers, prison workers, etc.

ID Care’s Role in Infection Prevention and Fighting COVID-19

As the largest infectious disease practice in New Jersey and on the East Coast, ID experts have been heavily involved in working with healthcare organizations as well as caring for patients throughout this pandemic. ID Care doctors have been on the frontlines, treating over 25% of hospitalized COVID-19 cases in New Jersey. ID Care physicians are also involved in orchestrating policies that protect communities at the state and local levels. And many ID Care physicians sit on hospital boards to drive policy and programs for vital infection prevention and control. ID Care continues to encourage everyone to get vaccinated to protect the New Jersey communities it serves. If you have questions regarding COVID-19 variants, vaccines, or the third dose, please give us a call at 908-281-0610 or visit

COVID-19, Infectious Disease Blog, Markou, Theodore