Fayetteville public health officer answers readers' questions related to covid-19 vaccinations

FAYETTEVILLE -- The Northwest Arkansas Democrat-Gazette has an online resource for readers to ask questions about covid-19 and its impact on the region.

Dr. Marti Sharkey, Fayetteville's public health officer, answers the questions. Sharkey is a pediatrician with a background in infectious disease. She reports to the city Board of Health, which advises city officials on matters related to the health and well-being of residents.

The newspaper will post periodic updates with Sharkey's answers to readers' questions. Today's answers pertain to questions about covid-19 vaccination.

To ask a question, visit nwaonline.com/askcovidquestions. Questions should be limited to topics related to the pandemic.

QUESTION: What do we need to know about which medical conditions and risk factors affect our vaccine eligibility timeline? And once I am eligible, how can I get signed up for the vaccine?

SHARKEY: Currently, Arkansas is in phase 1-B of its vaccination plan. We are currently vaccinating educators and those over 70 years of age (65 as of Feb. 23). The next part of this phase includes food/agricultural workers, firefighters, police and correctional staff not in 1-A, manufacturing workers, grocery store workers, public transit workers, U.S. Postal Service workers and essential government/community workers. As this next part only includes those who are at increased risk due to their employment, the vast majority will arrange for vaccination through their employer.

For the next phase, 1-C, people with high-risk medical conditions and workers in transportation and logistics, water and wastewater, food service, shelter and housing, finance, information technology and communications, energy, media, public safety and public health workers will be vaccinated.

Per the federal Centers for Disease Control and Prevention, the following are considered high-risk medical conditions: pregnancy; cancer; chronic kidney disease; COPD (chronic obstructive pulmonary disease); Down syndrome; heart conditions such as heart failure, coronary artery disease, or cardiomyopathies; immunocompromised state (weakened immune system) from solid organ transplant, obesity and severe obesity; sickle cell disease; smoking; and Type 2 diabetes mellitus.

In Arkansas, this group comprises a significant portion of our population, so we should expect that it will be broken down into smaller groups based upon vaccine availability. For instance, the state of New York is starting to vaccinate individuals with two or more high-risk conditions, since the more risk factors that you have, the higher your risk for severe morbidity and mortality.

Once you are eligible, you need to be paying attention to all media to learn how to sign up for your vaccine. The Arkansas Department of Health website is an excellent place to start, and I recommend checking both the city health officer website (fayetteville-ar.gov/3960/City-Health-Officer-Updates) as well as my Facebook page (facebook.com/marti.b.sharkey/) for routine updates for Fayetteville and Washington County.

QUESTION: What is the percentage of immunity after the first shot and how many days after the shots does immunity kick in?

SHARKEY: The Pfizer-BioNTech vaccine is roughly 52% effective 12 to 14 days after the first dose. The second dose is 95% effective one week after the second dose. The Moderna vaccine can provide 80.2% protection after one dose, compared to 95.6% after the second (in people aged 18 to 65 -- it's 86.4% in those older than 65).

QUESTION: What is the recommendation on receiving the covid-19 vaccine if you are pregnant? Have there been studies to document safety to a fetus?

SHARKEY: The American College of Obstetrics and Gynecologists recommends that covid-19 vaccines should be given to pregnant women who meet criteria for vaccination based on Advisory Committee on Immunization Practices-recommended priority groups. Currently, there are not any safety data on the use of covid-19 vaccines during pregnancy. However, there also are not any data that contraindicates their use, and no safety signals were generated from developmental and reproductive toxicology studies for Pfizer-BioNtech and Moderna covid-19 vaccines. Therefore, in the interest of patient autonomy, ACOG recommends that pregnant women be free to make their own decision regarding covid-19 vaccination. Although pregnant women are encouraged to discuss vaccination considerations with their clinical care team when feasible, documentation of such a discussion should not be required prior to receiving a covid-19 vaccine.

QUESTION: How long before we know if those who receive the covid vaccine can or cannot become infected and transmit the virus to others? When will we know if the vaccine prevents infection and/or only prevents consequential disease progression?

SHARKEY: Currently, there is not any conclusive evidence to claim the covid-19 vaccine stops people spreading the virus that causes the disease, nor is there for the opposite. Early findings from Oxford/AstraZeneca revealed its vaccine could have some effect on transmitting the virus, while similar results have also been reported by Pfizer/BioNTech.

Scientists do not yet know whether covid-19 vaccinations will reduce transmission because this was not tested in the trials. Instead, they found candidate vaccines were able to prevent symptomatic and severe effects of covid-19, meaning future research would need to take this further. For instance, it would need to look deeper into how the vaccine works in the body -- whether it prevents an individual getting infected altogether, or whether it simply stops a person becoming sick. With the latter, this could mean the virus continues to replicate in the nose and throat and is still able to spread.

QUESTION: After I am vaccinated for covid-19, how does my day-to-day activity change? If the answer is it does not, please explain.

SHARKEY: The first thing that you will want to do after getting vaccinated is to breathe a sigh of relief. The vaccines were proven to be more than 90% effective in preventing severe illness; however, it may still be possible to spread the virus to others. Data to answer that question is being gathered continually, and I hope that Moderna and Pfizer could have answers to that question when they apply for regular authorization from the U.S. Food and Drug Administration. That means it's not time to throw away face masks. Public safety measures will be critical for the near term, until it's clear whether vaccinated people can transmit the virus and until enough people get vaccinated to reach herd immunity, which health officials estimate to be 75-80% of the population.

Life in the early months of vaccination will continue to look the same. Until the vaccine is more widely available, its effects will be limited and there will continue to be substantial numbers of new virus cases, hospitalizations and deaths, although we are starting to see these numbers decline. Additionally, we do not yet know how the new variants of the virus will impact our vaccination efforts.

Groups of vaccinated people may also start to feel more comfortable gathering together for family reunions, trips, concerts or other get-togethers. The risk of getting seriously ill is minimal, even when congregating indoors. It's not zero. The Pfizer and Moderna vaccines have a 5-10% risk of being ineffective. Depending on the vaccine, it can take four to five weeks to be effective or one week after receiving the second dose. You can feel safe that you're not going to get severely ill and die from that gathering. But you don't know what impact you would have on the broader community.