Personal Physicians
David Katzman, MD & Jennifer DeLaney, MD Internal Medicine Specialists
What's New on the COVID Vaccine Front?
David Katzman, MD
Vaccine-Induced Immunity vs Natural Immunity
Vaccines work because they mimic our body’s immune system when exposed to a virus.  Is vaccine-acquired immunity better than immunity acquired by being infected by COVID?  Although a controversial issue, our answer is Yes! And here is why: The immunity generated by a COVID infection appears to be proportional to the severity of the infection; thus, a mild or asymptomatic infection (think Omicron) is unlikely to produce a significant immune response. Vaccines, on the other hand, typically generate a predictable response, and we have a better understanding of when the immunity may wane and boosters would be needed. Our very clear answer if you have had a Covid infection is to get the primary series of one of the mRNA vaccines, and boosters when indicated. You will hopefully be hyperimmune! 


Nasal Vaccines Are on the Way 


While the developmental speed and effectiveness of the Covid vaccines have been truly remarkable, the immunity they produce is located in the blood or bone marrow instead of the entry ways for the virus - the mouth and nose. Thus, it takes a day or two for the body to develop an immune response and send the proper immune response to the nose and mouth, allowing for viral replication, asymptomatic carriage and spread. The nasal vaccines in development would coat the mouth, throat and nose with long-lasting antibodies right away. This would be much better at preventing infection and especially person-to-person spread. They have been shown to protect animals against coronavirus and are currently in Phase 3 human trials. Stay tuned! 

Time for a 4th COVID shot?

The CDC has recently recommended a 4th booster shot for those individuals over 18 who are immunosuppressed. This would include those with cancer getting chemotherapy, those with blood or bone marrow cancers, and those on immunosuppressive medications for organ transplants or inflammatory conditions. The shot can be given at least three months after the third dose of any mRNA vaccine (Pfizer or Moderna). If you have questions whether you fall into this category, please give us a call!
Jennifer DeLaney, MD

The Omicron wave is declining with new cases down more than 50% from our peak 2 weeks ago. However, cases are still high, with more than twice the number of daily cases of last year’s peak. Unfortunately, Omicron infection does not seem to give long-term immunity and vaccine efficacy wanes over time.


So how do you navigate indoor activities with less risk?

  • Avoid crowded, closed-in spaces
  • Wear a mask whenever you are inside in public and aren’t eating and drinking
  • Make it a good mask (N95>KF94>KN95)
  • Wear your mask correctly

The CDC has released a widely-shared graphic showing the reduction in risk of catching COVID with different types of masks:


How can I tell if my mask is a good one?

  • If it is made of cloth or is a surgical mask, it is not a good one.
  • N95s are regulated by the US government to have excellent filtration and tight fit due to the head straps. These are your best choice for safety. Here are my personal favorites for comfort: 3M Aura, Indiana Face Mask, and Halyard or Gerson's Duckbill. You can purchase a variety of US made N95s and KN95s at
  • KF94s are regulated by the South Korean government and come in children’s sizes. The ear loops don’t always give as tight a fit, but many find them more comfortable.
  • KN95s are made in China and are not certified by the government. There are many fakes. See the link to Armbrust (above) and Bona Fide Masks for some reputable brands.

How can I tell if my N95, KF94 or KN95 is a fake?

  • N95s should have N95, the manufacturer name, the word NIOSH and the TC number printed on the mask. They should also have head straps, not ear loops.
  • KF94s should come individually packaged
  • KN95s should have the GB2626 number with 2009 or 2016 printed on the packaging. If you are going to use KN95s, I recommend purchasing through Bona Fide Masks (link above) as they only stock certified equipment.

Mask fit is as important as the material. The reason why surgical masks are not as effective is that 50% of the air you breathe does not go through the filter but enters your airway through gaps around the edge of the mask. This leakage is even worse with fabric masks. Here is a quick video on how to get a good fit with a respirator: N95 fitting video

Many Thanks!

Our thanks to the Dennis and Judy Jones Family Foundation for donating 200 of our Powered Air-Purifying Respirations (PAPRs) to Ethiopia to protect Health Care Workers where only 1% of the population is fully vaccinated. Their generosity will help the most vulnerable to Covid in this impoverished and war-torn country. These PAPRs will be joining our other PAPRs in use in India, Peru and Guatemala.

New Insurance, Address or Email?
Please let us know at your next point of care if your insurance, address, email, or any other demographics have changed. It's important to keep your chart up to date as we utilize this information for office tasks such as placing outside orders/labs and sending invoices. Thank you!
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