Pregnant & Breastfeeding Women Who Get the COVID-19 Vaccine Are Protecting Their Infants, Research Suggests
Becky Cummings had multiple reasons to get vaccinated against COVID-19 while tending to her firstborn, Clark, who arrived in September 2020 at 27 weeks.
The 29-year-old intensive care unit nurse in Greensboro, North Carolina, had witnessed the devastation day in and day out as the virus took its toll on the young and old. But when she was offered the vaccine, she hesitated, skeptical of its rapid emergency use authorization.
Exclusion of pregnant and lactating mothers from clinical trials fueled her concerns. Ultimately, though, she concluded the benefits of vaccination outweighed the risks of contracting the potentially deadly virus.
"Long story short," Cummings says, in December "I got vaccinated to protect myself, my family, my patients, and the general public."
At the time, Cummings remained on the fence about breastfeeding, citing a lack of evidence to support its safety after vaccination, so she pumped and stashed breast milk in the freezer. Her son is adjusting to life as a preemie, requiring mother's milk to be thickened with formula, but she's becoming comfortable with the idea of breastfeeding as more research suggests it's safe.
"If I could pop him on the boob," she says, "I would do it in a heartbeat."
Now, a study recently published in the Journal of the American Medical Association found "robust secretion" of specific antibodies in the breast milk of mothers who received a COVID-19 vaccine, indicating a potentially protective effect against infection in their infants.
The presence of antibodies in the breast milk, detectable as early as two weeks after vaccination, lasted for six weeks after the second dose of the Pfizer-BioNTech vaccine.
"We believe antibody secretion into breast milk will persist for much longer than six weeks, but we first wanted to prove any secretion at all after vaccination," says Ilan Youngster, the study's corresponding author and head of pediatric infectious diseases at Shamir Medical Center in Zerifin, Israel.
That's why the research team performed a preliminary analysis at six weeks. "We are still collecting samples from participants and hope to soon be able to comment about the duration of secretion."
As with other respiratory illnesses, such as influenza and pertussis, secretion of antibodies in breast milk confers protection from infection in infants. The researchers expect a similar immune response from the COVID-19 vaccine and are expecting the findings to spur an increase in vaccine acceptance among pregnant and lactating women.
A COVID-19 outbreak struck three families the research team followed in the study, resulting in at least one non-breastfed sibling developing symptomatic infection; however, none of the breastfed babies became ill. "This is obviously not empirical proof," Youngster acknowledges, "but still a nice anecdote."
Leaps.org inquired whether infants who derive antibodies only through breast milk are likely to have a lower immunity than infants whose mothers were vaccinated while they were in utero. In other words, is maternal transmission of antibodies stronger during pregnancy than during breastfeeding, or about the same?
"This is a different kind of transmission," Youngster explains. "When a woman is infected or vaccinated during pregnancy, some antibodies will be transferred through the placenta to the baby's bloodstream and be present for several months." But in the nursing mother, that protection occurs through local action. "We always recommend breastfeeding whenever possible, and, in this case, it might have added benefits."
A study published online in March found COVID-19 vaccination provided pregnant and lactating women with robust immune responses comparable to those experienced by their nonpregnant counterparts. The study, appearing in the American Journal of Obstetrics and Gynecology, documented the presence of vaccine-generated antibodies in umbilical cord blood and breast milk after mothers had been vaccinated.
Natali Aziz, a maternal-fetal medicine specialist at Stanford University School of Medicine, notes that it's too early to draw firm conclusions about the reduction in COVID-19 infection rates among newborns of vaccinated mothers. Citing the two aforementioned research studies, she says it's biologically plausible that antibodies passed through the placenta and breast milk impart protective benefits. While thousands of pregnant and lactating women have been vaccinated against COVID-19, without incurring adverse outcomes, many are still wondering whether it's safe to breastfeed afterward.
It's important to bear in mind that pregnant women may develop more severe COVID-19 complications, which could lead to intubation or admittance to the intensive care unit. "We, in our practice, are supporting pregnant and breastfeeding patients to be vaccinated," says Aziz, who is also director of perinatal infectious diseases at Stanford Children's Health, which has been vaccinating new mothers and other hospitalized patients at discharge since late April.
Earlier in April, Huntington Hospital in Long Island, New York, began offering the COVID-19 vaccine to women after they gave birth. The hospital chose the one-shot Johnson & Johnson vaccine for postpartum patients, so they wouldn't need to return for a second shot while acclimating to life with a newborn, says Mitchell Kramer, chairman of obstetrics and gynecology.
The hospital suspended the program when the Food and Drug Administration and the Centers for Disease Control and Prevention paused use of the J&J vaccine starting April 13, while investigating several reports of dangerous blood clots and low platelet counts among more than 7 million people in the United States who had received that vaccine.
In lifting the pause April 23, the agencies announced the vaccine's fact sheets will bear a warning of the heightened risk for a rare but serious blood clot disorder among women under age 50. As a result, Kramer says, "we will likely not be using the J&J vaccine for our postpartum population."
So, would it make sense to vaccinate infants when one for them eventually becomes available, not just their mothers? "In general, most of the time, infants do not have as good of an immune response to vaccines," says Jonathan Temte, associate dean for public health and community engagement at the University of Wisconsin School of Medicine and Public Health in Madison.
"Many of our vaccines are held until children are six months of age. For example, the influenza vaccine starts at age six months, the measles vaccine typically starts one year of age, as do rubella and mumps. Immune response is typically not very good for viral illnesses in young infants under the age of six months."
So far, the FDA has granted emergency use authorization of the Pfizer-BioNTech vaccine for children as young as 16 years old. The agency is considering data from Pfizer to lower that age limit to 12. Studies are also underway in children under age 12. Meanwhile, data from Moderna on 12-to 17-year-olds and from Pfizer on 12- to 15-year-olds have not been made public. (Pfizer announced at the end of March that its vaccine is 100 percent effective in preventing COVID-19 in the latter age group, and FDA authorization for this population is expected soon.)
"There will be step-wise progression to younger children, with infants and toddlers being the last ones tested," says James Campbell, a pediatric infectious diseases physician and head of maternal and child clinical studies at the University of Maryland School of Medicine Center for Vaccine Development.
"Once the data are analyzed for safety, tolerability, optimal dose and regimen, and immune responses," he adds, "they could be authorized and recommended and made available to American children." The data on younger children are not expected until the end of this year, with regulatory authorization possible in early 2022.
For now, Vonnie Cesar, a family nurse practitioner in Smyrna, Georgia, is aiming to persuade expectant and new mothers to get vaccinated. She has observed that patients in metro Atlanta seem more inclined than their rural counterparts.
To quell some of their skepticism and fears, Cesar, who also teaches nursing students, conceived a visual way to demonstrate the novel mechanism behind the COVID-19 vaccine technology. Holding a palm-size physical therapy ball outfitted with clear-colored push pins, she simulates the spiked protein of the coronavirus. Slime slathered at the gaps permeates areas around the spikes—a process similar to how our antibodies build immunity to the virus.
These conversations often lead hesitant patients to discuss vaccination with their husbands or partners. "The majority of people I'm speaking with," she says, "are coming to the conclusion that this is the right thing for me, this is the common good, and they want to make sure that they're here for their children."
CORRECTION: An earlier version of this article mistakenly stated that the COVID-19 vaccines were granted emergency "approval." They have been granted emergency use authorization, not full FDA approval. We regret the error.
What's the case-fatality rate?
Currently, the official rate is 3.4%. But this is likely way too high. China was hit particularly hard, and their healthcare system was overwhelmed. The best data we have is from South Korea. The Koreans tested 210,000 people and detected the virus in 7,478 patients. So far, the death toll is 53, which is a case-fatality rate of 0.7%. This is seven times worse than the seasonal flu (which has a case-fatality rate of 0.1%).
What's the best way to clean your hands? Soap and water? Hand sanitizer?
Soap and water is always best. Be sure to wash your hands thoroughly. (The CDC recommends 20 seconds.) If soap and water are not available, the CDC says to use hand sanitizer that is at least 60% alcohol. The problem with hand sanitizer, however, is that people neither use enough nor spread it over their hands properly. Also, the sanitizer should be covering your hands for 10-15 seconds, not evaporating before that.
How often should I wash my hands?
You should wash your hands after being in a public place, before you eat, and before you touch your face. It's a good idea to wash your hands after handling money and your cell phone, too.
How long can coronavirus live on surfaces?
It depends on the surface. According to the New York Times, "[C]old and flu viruses survive longer on inanimate surfaces that are nonporous, like metal, plastic and wood, and less on porous surfaces, like clothing, paper and tissue." According to the Journal of Hospital Infection, human coronaviruses "can persist on inanimate surfaces like metal, glass or plastic for up to 9 days, but can be efficiently inactivated by surface disinfection procedures with 62–71% ethanol, 0.5% hydrogen peroxide or 0.1% sodium hypochlorite within 1 minute." (Note: Sodium hypochlorite is bleach.)
Can Lysol wipes kill it?
Maybe not. It depends on the active ingredient. Many Lysol products use benzalkonium chloride, which the aforementioned Journal of Hospital Infection paper said was "less effective." The EPA has released a list of disinfectants recommended for use against coronavirus.
Should you wear a mask in public?
The CDC does not recommend that healthy people wear a mask in public. The benefit is likely small. However, if you are sick, then you should wear a mask to help catch respiratory droplets as you exhale.
Will pets give it to you?
That can't be ruled out. There is a documented case of human-to-canine transmission. However, an article in LiveScience explains that canine-to-human is unlikely.
Are there any "normal" things we are doing that make things worse?
Yes! Not washing your hands!!
What does it mean that previously cleared people are getting sick again? Is it the virus within or have they caught it via contamination?
It's not entirely clear. It could be that the virus was never cleared to begin with. Or it could be that the person was simply infected again. That could happen if the antibodies generated don't last long.
Will the virus go away with the weather/summer?
Quite likely, yes. Cold and flu viruses don't do well outside in summer weather. (For influenza, the warm weather causes the viral envelope to become a liquid, and it can no longer protect the virus.) That's why cold and flu season is always during the late fall and winter. However, some experts think that it is a "false hope" that the coronavirus will disappear during the summer. We'll have to wait and see.
And will it come back in the fall/winter?
That's a likely outcome. Again, we'll have to wait and see. Some epidemiologists think that COVID-19 will become seasonal like influenza.
Does dry or humid air make a difference?
Flu viruses prefer cold, dry weather. That could be true of coronaviruses, too.
What is the incubation period?
According to the World Health Organization, it's about 5 days. But it could be anywhere from 1 to 14 days.
Should you worry about sitting next to asymptomatic people on a plane or train?
It's not possible to tell if an asymptomatic person is infected or not. That's what makes asymptomatic people tricky. Just be cautious. If you're worried, treat everyone like they might be infected. Don't let them get too close or cough in your face. Be sure to wash your hands.
Should you cancel air travel planned in the next 1-2 months in the U.S.?
There are no hard and fast rules. Use common sense. Avoid hotspots of infection. If you have a trip planned to Wuhan, you might want to wait on that one. If you have a trip planned to Seattle and you're over the age of 60 and/or have an underlying health condition, you may want to hold off on that, too. If you do fly on a plane, former FDA commissioner Dr. Scott Gottlieb recommends cleaning the back of your seat and other close contact areas with antiseptic wipes. He also refuses to take anything handed out by flight attendants, since he says the biggest route of transmission comes from touching contaminated surfaces (and then touching your face).
There have been reports of an escalation of hate crimes towards Asian Americans. Can the microbiologist help illuminate that this disease has impacted all racial groups?
People might be racist, but COVID-19 is not. It can infect anyone. Older people (i.e., 60 years and older) and those with underlying health conditions are most at risk. Interestingly, young people (aged 9 and under) are minimally impacted.
To what extent/if any should toddlers -- who put everything in mouth -- avoid group classes like Gymboree?
If they get infected, toddlers will probably experience only a mild illness. The problem is if the toddler then infects somebody at higher risk, like grandpa or grandma.
Should I avoid events like concerts or theater performances if I live in a place where there is known coronavirus?
It's not an unreasonable thing to do.
Any special advice or concerns for pregnant women?
There isn't good data on this. Previous evidence, reported by the CDC, suggests that pregnant women may be more susceptible to respiratory viruses.
Advice for residents of long-term care facilities/nursing homes?
Remind the nurse or aide to constantly wash their hands.
Can we eat at Chinese restaurants? Does eating onions kill viruses? Can I take an Uber and be safe from infection?
Yes. No. Does the Uber driver or previous passengers have coronavirus? It's not possible to tell. So, treat an Uber like a public space and behave accordingly.
What public spaces should we avoid?
That's hard to say. Some people avoid large gatherings, others avoid leaving the house. Ultimately, it's going to depend on who you are and what sort of risk you're willing to take. (For example, are you young and healthy or old and sick?) I would be willing to do things that I would advise older people avoid, like going to a sporting event.
What are the differences between the L strain and the S strain?
That's not entirely clear, and it's not even clear that they are separate strains. There are some genetic differences between them. However, just because RNA viruses mutate doesn't necessarily mean that the virus will mutate to something more dangerous or unrecognizable by our immune system. The measles virus mutates, but it more or less remains the same, which is why a single vaccine could eradicate it – if enough people actually were willing to get a measles shot.
Should I wear disposable gloves while traveling?
No. If you touch something that's contaminated, the virus will be on your glove instead of your hand. If you then touch your face, you still might get sick.
The Best Coronavirus Experts to Follow on Twitter
As the coronavirus tears across the globe, the world's anxiety is at a fever-pitch, and we're all craving information to stay on top of the crisis.
But turning to the Internet for credible updates isn't as simple as it sounds, since we have an invisible foe spreading as quickly as the virus itself: misinformation. From wild conspiracy theories to baseless rumors, an infodemic is in full swing.
For the latest official information, you should follow the CDC, WHO, and FDA, in addition to your local public health department. But it's also helpful to pay attention to the scientists, doctors, public health experts and journalists who are sharing their perspectives in real time as new developments unfold. Here's a handy guide to get you started:
VIROLOGY
Dr. Trevor Bedford/@trvrb: Scientist at the Fred Hutchinson Cancer Research Center studying viruses, evolution and immunity.
Dr. Benhur Lee/@VirusWhisperer: Professor of microbiology at the Icahn School of Medicine at Mount Sinai
Dr. Angela Rasmussen/@angie_rasmussen: Virologist and associate research scientist at Columbia University
Dr. Florian Krammer/@florian_krammer: Professor of Microbiology at the Icahn School of Medicine at Mount Sinai
EPIDEMIOLOGY:
Dr. Alice Sim/@alicesim: Infectious disease epidemiologist and consultant at the World Health Organization
Dr. Tara C. Smith/@aetiology: Infectious disease specialist and professor at Kent State University
Dr. Caitlin Rivers/@cmyeaton: Epidemiologist and assistant professor at the Johns Hopkins Bloomberg School of Public Health
Dr. Michael Mina/@michaelmina_lab: Physician and Assistant Professor of Epidemiology & Immunology at the Harvard TH Chan School of Public Health
INFECTIOUS DISEASE:
Dr. Nahid Bhadelia/@BhadeliaMD: Infectious diseases physician and the medical director of Special Pathogens Unit at Boston University School of Medicine
Dr. Paul Sax/@PaulSaxMD: Clinical Director of the Division of Infectious Diseases at Brigham and Women's Hospital
Dr. Priya Sampathkumar/@PsampathkumarMD: Infectious Disease Specialist at the Mayo Clinic
Dr. Krutika Kuppalli/@KrutikaKuppalli: Medical doctor and Infectious Disease Specialist based in Palo Alto, CA
PANDEMIC PREP:
Dr. Syra Madad/@syramadad: Senior Director, System-wide Special Pathogens Program at New York City Health + Hospitals
Dr Sylvie Briand/@SCBriand: Director of Pandemic and Epidemic Diseases Department at the World Health Organization
Jeremy Konyndyk/@JeremyKonyndyk: Senior Policy Fellow at the Center for Global Development
Amesh Adalja/@AmeshAA: Senior Scholar at the Johns Hopkins University Center for Health Security
PUBLIC HEALTH:
Scott Becker/@scottjbecker: CEO of the Association of Public Health Laboratories
Dr. Scott Gottlieb/@ScottGottliebMD: Physician, former commissioner of the Food and Drug Administration
APHA Public Health Nursing/@APHAPHN: Public Health Nursing Section of the American Public Health Association
Dr. Tom Inglesby/@T_Inglesby: Director of the Johns Hopkins SPH Center for Health Security
Dr. Nancy Messonnier/@DrNancyM_CDC: Director of the Center for the National Center for Immunization and Respiratory Diseases (NCIRD)
Dr. Arthur Caplan/@ArthurCaplan: Professor of Bioethics at New York University Langone Medical Center
SCIENCE JOURNALISTS:
Laura Helmuth/@laurahelmuth: Incoming Editor in Chief of Scientific American
Helen Branswell/@HelenBranswell: Infectious disease and public health reporter at STAT
Sharon Begley/@sxbegle: Senior writer at STAT
Carolyn Johnson/@carolynyjohnson: Science reporter at the Washington Post
Amy Maxmen/@amymaxmen: Science writer and senior reporter at Nature
Laurie Garrett/@Laurie_Garrett: Pulitzer-prize winning science journalist, author of The Coming Plague, former senior fellow for global health at the Council on Foreign Relations
Soumya Karlamangla/@skarlamangla: Health writer at the Los Angeles Times
André Picard/@picardonhealth: Health Columnist, The Globe and Mail
Caroline Chen/@CarolineYLChen: Healthcare reporter at ProPublica
Andrew Jacobs/@AndrewJacobsNYT: Science reporter at the New York Times
Meg Tirrell/@megtirrell: Biotech and pharma reporter for CNBC
Kira Peikoff was the editor-in-chief of Leaps.org from 2017 to 2021. As a journalist, her work has appeared in The New York Times, Newsweek, Nautilus, Popular Mechanics, The New York Academy of Sciences, and other outlets. She is also the author of four suspense novels that explore controversial issues arising from scientific innovation: Living Proof, No Time to Die, Die Again Tomorrow, and Mother Knows Best. Peikoff holds a B.A. in Journalism from New York University and an M.S. in Bioethics from Columbia University. She lives in New Jersey with her husband and two young sons. Follow her on Twitter @KiraPeikoff.