New York University researchers drew blood from eight people who received Moderna’s vaccine, nine people who got Pfizer’s, and 10 people that got J&J’s, according to a preprint version of the study posted Tuesday. They compared the antibody response against Delta with the antibody response against the original strain of the coronavirus.
In the Moderna and Pfizer group, the antibody response was three times lower against Delta, on average. For J&J’s shot, it was 5.4 times lower against Delta, the study authors said.
The study authors said that the lower antibody response for J&J’s shot “could result in decreased protection.” More than 9 million Americans have received the vaccine.
Dr. Ned Landau, who led the experiment, told CNBC that the findings suggested people who got the J&J vaccine “should at least consider” a second dose of the same vaccine, or one from Pfizer or Moderna.
But other experts aren’t convinced about the findings of a small lab study, which hasn’t yet been scrutinized by other experts in a peer review. They say Johnson & Johnson’s vaccine could still work against Delta in real life.
Insider’s Hilary Brueck reported Tuesday that fully vaccinated people can get COVID-19 – but if they do, they usually get mild symptoms, or none at all.
Eric Topol, professor of Molecular Medicine at the Scripps Research Institute, said on Twitter Tuesday that the antibody response with J&J’s vaccine was above the threshold “for concern.”
“There’s also the T cell response,” he added. The T cell response is another aspect of the immune system – it is harder to study in the lab, but is thought to be crucial to protect against variants. The NYU team didn’t examine this in their study.
Peter Chin-Hong, professor of infectious disease at University of California, San Francisco, told ABC10 News that “you can’t necessarily extrapolate laboratory-based studies to what happens in real life,” citing J&J’s performance against the Beta variant.
The same NYU study showed that the J&J vaccine’s antibody response against Beta variant, first found in South Africa, was 6.5 times lower than against the original variant. But in humans, J&J’s vaccine was 64% effective at preventing moderate to severe disease in its South Africa trials, when 95% infections were caused by the Beta variant.
Real-world data from South Africa, posted by the South African Medical Research Council on July 1, showed that 94% of health workers who were vaccinated with J&J’s shot and then caught COVID-19 only had mild infections.
The company said on July 2 that its COVID-19 vaccine should work against Delta.
Neither The Centers for Disease Control and Prevention nor the Food and Drug Administration recommend that people who received J&J take an extra dose. There isn’t enough data to support the approach, they say.
J&J said the move is out of an “abundance of caution,” and that daily exposure to benzene at such low levels would not be expected to cause adverse health consequences. Retailers will be notified to stop selling the products and return them to J&J.
The move comes just over a month after a lab singled out these products among 40 other sunscreen products as risky, saying they were contaminated with benzenes.
Valisure, a pharmaceutical testing company, tested 294 batches of sunscreen from 69 different brands. The other benzene-containing sunscreens included some products by Banana Boat, Walgreens, and CVS Health.
J&J said it tested the sunscreens in an independent laboratory to corroborate the results, and is now investigating how the chemical made its way into the products.
Repeated exposure to the benzene in large amounts is linked to cancers such as leukemia, multiple myeloma, and non-Hodgkin lymphoma.
Few states have had a harder time vaccinating people than Arkansas.
Less than 43% of the state’s population has received at least one vaccine dose, and just 34% of residents are fully vaccinated – among the lowest vaccination rates in the US. That made the state a sitting duck for the Delta variant, which is significantly more transmissible than the original virus or other variants. As Delta spreads rapidly among unvaccinated people in the US, Arkansas and its neighbor, Missouri, have become the epicenter of the US outbreak.
The maps below, from the Centers for Disease Control and Prevention, show how Arkansas’ latest surge correlates with its low vaccination rate. Counties with at least 100 cases per 100,000 people (in blue) also have vaccination rates below 40% (in purple).
Arkansas reported more than 1,200 new coronavirus cases on Friday – its highest tally in nearly five months. The state’s daily coronavirus cases more than doubled over the last two weeks, from around 290 to 600 cases per day, on average. Data compiled by Scripps Research’s Outbreak.info tracker suggests that Delta may account for more than 80% of Arkansas’ new coronavirus infections. That’s among the highest shares of Delta infections in the country.
Hospitalizations have risen in the state as a result: Arkansas’ average is up 42% in the last two weeks, from around 270 to 380 hospitalizations per day.
The state’s health director, Dr. José Romero, blames the low vaccination rate on widespread vaccine hesitancy in rural areas.
Romero told Insider that the state’s health department arranged for essential workers to get access to shots at their places of work, but demand for the service was low. Even teachers have been reluctant to get their shots, he said: At most, 45% of teachers and staff at Arkansas schools have been vaccinated.
Now, the health department is planning to return to schools and workplaces to offer the shots a second time. Officials are also hosting town halls to address residents’ concerns about vaccine safety, since misinformation on social media has led people to think, falsely, that coronavirus vaccines might increase the risk of infertility.
Since May, Arkansas’ government has also been offering incentives for those who get vaccinated: $20 gift certificates for the Arkansas Game and Fish Commission or $20 lottery tickets.
But if those efforts don’t pan out, there’s no backup plan.
“We’ve done everything we can,” Romero said. “We’ve made the vaccine available. We’ve gone the extra mile to make it pretty much on demand if you want it. We’ve made testing available all around the state through various means. I don’t think there’s anything else that we can do at this point.”
Many rural residents don’t see a need to get vaccinated
Access to shots may still be a problem in Arkansas, despite the state’s efforts. Rural communities are historically hard to reach through vaccination campaigns, and around 42% of Arkansas counties are rural. Research from Boston Children’s Hospital suggests that several Arkansas counties qualify as “vaccine deserts,” with the nearest COVID-19 vaccination site more than a 15-minute drive away.
But Romero doesn’t think that’s the issue.
“We really do have vaccine in every county in the state,” he said. “This is the home of Walmart, and Walmart is a federal partner. I say this tongue-in-cheek: You can’t swing a cat without hitting Walmart. They’re everywhere and they’re distributing the vaccine.”
Romero said he is more concerned about how difficult it has been to convince rural residents that the coronavirus is dangerous, even with the spread of Delta.
“There is a significant population within the state that still doesn’t believe this to be a major health threat,” he said. “They consider themselves not at risk because they’re healthy.”
Even within his own health department, Romero added, there are still employees “that are not believers in the vaccine.”
Arkansas has one of the highest rates of vaccine hesitancy in the country. As of June, the Department of Health and Human Services estimated that 25% of the state’s population might be hesitant or unsure about getting a COVID-19 vaccine. Only three other states – Mississippi, Montana, and Wyoming – had higher hesitancy rates.
Arkansas has also struggled to get people to return for their second shots. Romero said 15% of people who had received their first dose of either Pfizer’s or Moderna’s vaccine hadn’t gone back for their second as of two weeks ago. Romero said he thinks it’s because many residents were deterred by the side effects of their first dose.
That’s particularly concerning given that new research suggests partially vaccinated people are more vulnerable to symptoms from Delta. A study published Thursday in the journal Nature found that just a single dose of Pfizer’s vaccine was either weakly or not at all effective against the variant.
As the Delta variant becomes the dominant COVID strain in the US, Americans are scrambling to strengthen their protections against the coronavirus.
For some people who got the single-dose Johnson & Johnson vaccine, that means getting another shot just in case.
However, the FDA and the CDC have not recommended doing so. Leading infectious disease expert Dr. Anthony Fauci said there’s no data yet to support it.
“Even though individual physicians would be doing that, from a clinical trial basis there’s no real fundamental scientific reason to do that right now,” Fauci said when asked about J&J boosters in a White House press briefing. “When those data become available, you will see recommendations change.”
J&J data suggests the shot is effective against variants
J&J has stood up against some worrisome variants, including the highly transmissible Delta variant.
The company found its vaccine produced a “strong” antibody response to the variants, according to two small, not-yet-peer-reviewed studies. It concluded that J&J vaccine recipients do not need a booster – and, for now, the CDC agrees.
“Right now, we have no information to suggest that you need a second shot after J&J, even with the Delta variant,” CDC director Rochelle Walensky told Today.
Angela Rasmussen, a virologist at the University of Saskatchewan, tweeted on Tuesday that she got a dose of the Pfizer vaccine to supplement the J&J vaccine she received in April. She said she was spurred by the Delta variant, and the history of successful vaccine boosters before COVID-19.
Other virus experts agree that, generally speaking, the strategy of mixing different kinds of shots to bolster disease protection can work well.
“You would expect some combinations to be: firstly safe, and to give – at minimum – comparable and quite possibly superior efficacy to some of the standard two-dose regimens,” immunologist John Moore told Insider.
Data from early studies about mixing vaccines have been promising. A recent study in the UK suggests that mixing the Pfizer and AstraZeneca vaccines yields a greater immune response than two doses of AstraZeneca’s shot.
Another study in Spain found that mixing doses successfully produced a boosted immune response. However, the study has not yet been peer-reviewed, and those preliminary results were announced in an online presentation.
Getting a booster shot in the US may be logistically difficult
Twitter users who already had their minds made up about getting an mRNA shot to follow up their J&J dose had some logistical questions about how to get a shot when you’re already, technically, vaccinated.
Dr. Vin Gupta, the COVID-19 chief medical officer of Amazon, tweeted an answer.
“If you received the 1-dose J&J, go and get 1-shot of Pfizer or Moderna as a ‘booster’ when you’re able,” he wrote. “Most I know who got J&J are doing it and are telling others the same – since two seems better than 1 re: delta.”
Christopher Murray, director of IHME, told Insider he thinks following up with an mRNA shot will soon become “smart strategy” for those who got the J&J jab – especially teachers looking ahead to the next school year.
The evidence in favor of a mix-and-match approach to coronavirus shots is growing.
Early data from a UK study, though not yet been peer reviewed, indicates that mixing the Pfizer and AstraZeneca vaccines yields a greater immune response than two doses of AstraZeneca’s shot. The researchers measured antibody levels among 830 volunteers who received either two doses of the same vaccine or a combination of Pfizer and AstraZeneca, four weeks apart.
Volunteers who got AstraZeneca’s shot followed by Pfizer’s showed nearly the same antibody levels – and an even higher number of T-cells – as those who’d received two doses of Pfizer. By contrast, volunteers who got Pfizer’s shot first and AstraZeneca’s second had slightly lower antibody levels than the reverse combination. But those levels were still were roughly five times higher than the antibody response after two doses of AstraZeneca.
“Mixing these two vaccines not only appears to be safe, but can give a higher immune response than the standard dosing regimens,” Deborah Dunn-Walters, a professor of immunology at the University of Surrey, said in a statement.
There are some caveats, though: The UK study examined immune-system responses, not real-world infection rates. Plus, research has shown that AstraZeneca’s vaccine is more effective when the doses are given 12 weeks apart. So the UK team is running a separate trial based on that interval, and those results haven’t been released yet.
For now, though, some experts think it might be beneficial to recommend a booster shot of Pfizer’s or Moderna’s mRNA vaccine for people who received a different initial shot.
“From this study, people who have had a first course of AstraZeneca should probably be offered the Pfizer vaccine (or possibly Moderna or Novavax dependent on the future trial data from this study) in the autumn rather than a repeat AstraZeneca,” Paul Hunter, a medicine professor at the University of East Anglia, said in a statement.
“People who had a Pfizer first course may not need an autumn booster,” he added, “but if they do, then it probably does not matter much which vaccine they are offered.”
Some countries already let residents mix and match
Even before coronavirus vaccines came out, some research had already indicated that mixing and matching vaccines in general could yield better results. Johnson & Johnson’s Ebola vaccine, for instance, uses an adenovirus shot followed by a modified version of a poxvirus. Researchers have tested different vaccine combos for a future HIV shot, too.
Already, some countries have started allowing residents to mix and match coronavirus vaccines.
Canada announced earlier this month that the Pfizer and Moderna shots could be used interchangeably, given the country’s low vaccine supply. Meanwhile, several European countries – including Germany, Sweden, France, Spain, and Italy – have said that people who received an initial dose of AstraZeneca’s shot can choose a different vaccine for their second dose, given the reports of rare blood clots linked to AstraZeneca’s vaccine.
Yet another mix-and-match study, this one funded by the National Institutes of Health, is giving participants a booster of Moderna’s vaccine after their initial regimen of Moderna, Pfizer, or Johnson & Johnson.
Joseph Hyser, a participant in that trial, recently told Insider that his side effects were a bit more severe after a booster of Moderna’s vaccine than after each of his doses of Pfizer’s vaccine. He said he woke up the day after his booster feeling “like I had done a very rigorous gym workout,” with chills and arm soreness – like he’d gotten a “hard punch in the shoulder.”
The NIH study could offer much-awaited insight into whether following J&J’s single-dose shot with a Moderna booster offers similar protection to a two-dose mRNA vaccine. But some experts who got J&J’s shot aren’t waiting. Angela Rasmussen, a virologist at the University of Saskatchewan, tweeted on Tuesday that she got the Pfizer vaccine to “top off” the J&J vaccine she received in April.
Rasmussen encouraged people who’d had J&J’s shot to speak with healthcare providers about getting an extra dose.
“We shouldn’t wait to make recommendations about this,” she wrote.
Hilary Brueck and Dr. Catherine Schuster-Bruce contributed reporting.
Pharmaceutical giant Johnson & Johnson will no longer sell opioids in the US as part of a $230 million settlement with the state of New York.
According to the Wall Street Journal, the settlement was reached just days before the case was set to go to trial Tuesday on Long Island.
The settlement does not impact the numerous other lawsuits the company faces in other states across the US from state and local governments who allege Johnson & Johnson and other pharmaceutical companies helped create the opioid epidemic.
“The opioid epidemic has wreaked havoc on countless communities across New York state and the rest of the nation, leaving millions still addicted to dangerous and deadly opioids,” New York Attorney General Letitia James said Saturday in a statement.
“Johnson & Johnson helped fuel this fire, but today they’re committing to leaving the opioid business – not only in New York, but across the entire country,” she added.
Settlement talks between drug companies and state and local governments have ramped up in recent weeks as trials have begun in California and West Virginia, sources told the WSJ.
In a statement, Johnson & Johnson said the settlement Saturday with the state of New York was not an admission of liability of wrongdoing.
“The Company’s actions relating to the marketing and promotion of important prescription pain medications were appropriate and responsible,” it said.
The trial in New York was scheduled to begin in March 2020 but was delayed due to the COVID-19 pandemic, according to the WSJ. Following New York’s settlement with Johnson & Johnson, the case will proceed next week with three other opioid makers, multiple drug distributors, and the pharmacy Walgreens Boots Alliance Inc., according to the report.
It will be the first opioid case to be heard in front of a jury, the WSJ noted.
The first opioid trial in the US was in Oklahoma in 2019 resulted in a $465 million loss against Johnson & Johson, the WSJ reported. The company is appealing that ruling, the report said.
“Our trial against the remaining defendants will commence this coming week, where we will lay bare the callous and deadly pattern of misconduct these companies perpetrated as they dealt dangerous and addictive opioids across our state,” James said Saturday. “As always, our goal remains getting funds to those devastated by opioids as quickly as possible.”
The New York trial is expected to last for four months, according to the WSJ.
The US government is stopping orders of Johnson & Johnson COVID-19 vaccines so states can try to use up stockpiled doses as vaccination rates drop, the Wall Street Journal reported on Thursday.
US state and federal health officials told The Journal that the Centers for Disease Control and Prevention (CDC) is banning states from ordering the J&J shot. Some of the officials said it was only a temporary measure.
Michigan, Oklahoma, and Illinois haven’t been able to order new supplies of the one-dose vaccine in recent weeks, according to health officials there. Some said their state had enough doses of the shot.
“It just hasn’t been included in our weekly allocations, from the feds, which means it is not available to order,” Keith Reed, deputy commissioner of Oklahoma’s state department of health, told the Journal.
It was unclear exactly why the government halted the J&J vaccine shipments based on the comments from officials, the Journal reported.
The vaccine suspension comes after the Food and Drug Administration (FDA) on Thursday extended the shelf life of the J&J vaccine from three months to four-and-a-half months when refrigerated.
J&J didn’t immediately respond to Insider’s request for comment. The drugmaker told the Journal that it would “continue to work with the US government and health authorities to support the use of our vaccine, which continues to play an important role, including among those who wish to be fully vaccinated with one shot.”
Just over half of the American adult population have received at least one dose of a COVID-19 shot, according to data from the CDC.
But vaccine uptake is dropping. On April 1, vaccination rates hit a peak of 4.3 million, but in June that number fell to an average of less than one million a day, CDC data showed.
Millions of Johnson & Johnson vaccines are set to expire in June, and thousands could be wasted because fewer and fewer Americans are getting vaccinated, according to reports by The Wall Street Journal and The New York Times.
Some states have considered shipping excess doses to other states or even overseas, but said they faced legal and logistical hurdles.
As the Food and Drug Administration (FDA) investigated the blood clot concerns in April, it told states to pause use of Johnson & Johnson’s shot. This, combined with the overall decline in vaccinations in the US and the public’s hesitancy towards Johnson & Johnson’s vaccine, has left states with millions of doses due to expire this month – and few people willing to take them.
Most Americans don’t get to choose which vaccine they receive, but some pharmacies only offer certain brands, so people may choose their pharmacy accordingly.
CDC data shows that just 53% of Johnson & Johnson vaccines delivered to states have been administered, compared to 83% for Moderna and 84% for Pfizer. Just over 10 million Johnson & Johnson are still waiting to be given out, largely due to the decline in vaccination rates and the FDA-mandated pause.
Ohio Gov. Mike DeWine said Monday that the state had around 200,000 doses of the Johnson & Johnson vaccine set to expire on June 23, while Dr. Jennifer Dillaha, Arkansas’ state epidemiologist, said on June 2 that it was pausing new vaccine orders because it already had up to 60,000 doses of Johnson & Johnson’s vaccine set to expire this month.
Dillaha told 5 News that overall demand for vaccines was dropping in Arkansas – but that the Johnson & Johnson shot was the least sought after.
Other states, including Michigan and Philadelphia, have reported similar problems – but they’ve struggled to shift excess doses elsewhere.
Pennsylvania’s Department of Health told The Journal that it had worked with the CDC to try to transfer Chester County’s 50,000 expiring Johnson and Johnson doses to Oregon. The deal fell through when Oregon said there wasn’t enough demand for the jab, officials told The Journal.
Ohio said it was not legally able to send the vaccine abroad or to other states, and said it had been “aggressively” working with vaccine providers to use as many doses as possible before they expire.
“There is a very, very small fraction of doses that have been sent out to states that will ultimately not be used,” Andy Slavitt, a White House pandemic adviser, said Tuesday, per The Times. He added that the FDA was looking into ways to extend the vaccine’s shelf life.
Leaders at Sunnyside Community Services, a non-profit center that serves neighborhoods in Queens, New York City, are well aware of the devastating toll COVID-19 has had on their community.
The coronavirus disease had killed more Queens residents than any other borough as of March 2020, when New York City became an epicenter of the pandemic. Queens has the second-highest death rate from COVID-19 among the five boroughs, according to the most recent city data.
In the area of Queens that encompasses Jackson Heights, Elmhurst, and Woodside, 1 in 12 people have had COVID-19 and 1 in 137 have died, according to The New York Times.
At a one-day pop-up vaccine clinic in New York City’s Sunnyside Community Services, workers said community members coming in to get a shot gave them hope about the COVID-19 pandemic’s end, but they will still work hard to ensure no vulnerable member gets left behind.
Jackie Lopez, who leads the COVID Free Queens Coalition at Sunnyside Community Services, told Insider though she feels hopeful about entering a new post-COVID era, she urged federal and state agencies to keep in mind how vulnerable communities have low vaccination rates.
Lopez said she’s heard community members say they can’t get a vaccine because they can’t take days off work if they have side effects. Black and Latino adults have a lower rate of vaccination than the average, according to the University of Minnesota. A volunteer team with the Association of American Medical Colleges said low-income neighborhoods have less access to vaccines, and these residents struggle with navigating the online sign-up processes.
“Our Black and brown communities, our immigrant communities were hit the hardest by the pandemic and we still have work to do to provide accessibility and continue to provide information,” Lopez said.
Inside a pop-up vaccine clinic in one of the hardest hit areas of COVID-19
On May 27, VIP StarNetwork, an on-demand health services company primarily for entertainment industry workers, hosted a one-day pop-up vaccine clinic at Sunnyside Community Services for one day. The May 27 pop-up vaccine site was Sunnyside Community Services’ first, and the organization has scheduled second-dose appointments for June 17.
Johonniuss Chemweno, the CEO of VIP StarNetwork, said the group has been working with the state government to bring pop-up clinics to diverse and low-income communities. VIP StarNetwork, which had been approved as a mass vaccination provider by a federal agency in February, had previously enforced COVID-19 safety protocols for Netflix and Amazon studios.
The pop-up vaccine clinic had a team of more than a dozen nurses ready to help walk-in visitors get a vaccine. The site allowed all adults and people aged 12 to 18 to get a Pfizer, Moderna, or Johnson & Johnson vaccine.
Chemweno told Insider he’s seen an uptick in people under 18 coming into pop-up vaccine sites. The US began inoculating teenagers with the Pfizer vaccine in May.
Recipients were allowed to choose which vaccine they got depending on availability, Chemweno said.
Nada Elrakaivy, a COVID Free Queens Coalition outreach specialist, told Insider many community members have been hesitant about receiving a Johnson & Johnson vaccine after the CDC reported a rare blood clot had been linked to six vaccine recipients. The welcome sign outside the vaccine clinic noted noted that the site had Pfizer vaccines, and two community members asked specifically for the Pfizer vaccine when entering the pop-up site.
Community members entered Sunnyside Community Services and checked-in with Valentina Valencia, an emergency medical technician, and Sofia Mejia, a registered nurse. The two said they had enjoyed “giving back to the community that needs it” through working at with Sunnyside Community services.
After checking in, a nurse administered the vaccine to community members, and recipients had to wait about 15 minutes for observation before leaving.
Elrakaivysaid her group has been giving out free masks to Queens residents on the streets, and providing them with information on how to get a COVID-19 test and vaccine. The COVID Free Queens Coalition took down the names of food vendors, who Elrakaivy said are high-risk due to interacting with many different people daily, and made vaccine appointments for those who were interested.
The team always has a Spanish-speaking person with them to communicate with the area’s Latino community.
“For the most part, every time we ask someone if they got the vaccine, they responded with a yes,” Elrakaivy said. “So Queens is doing pretty well. Better than we expected.”
How Sunnyside Community Services workers are dealing with vaccine hesitancy
Jonah Gensler, the associate executive director of Community Services, told Insider he had been engaging with the community throughout the pandemic.
Prior to the pandemic, Sunnyside Community Services held services for senior citizens, English classes for immigrant residents, and other programs for vulnerable people across Queens. Gensler said the non-profit reached with homebound seniors using their phone numbers gathered at previous Sunnyside Community Services events.
The group set up a food pantry when the pandemic hit to help struggling community members. Community Services has also hosted online town halls to get the word out about COVID-19 safety, Gensler said.
Gensler said a roadblock to getting community members vaccinated has been the hesitancy around getting a vaccine and distrust in the government, especially after wealthier areas got better access to vaccines than communities that had suffered during the height of the pandemic.
“We have heard that some community members say, ‘You know, at the height of this pandemic, when the communities in Elmhurst and Corona and Jackson Heights were suffering the most, we didn’t get all the support we needed,'” Gensler said. “And that does lead to hesitancy.”
But Lopez, the lead organizer of COVID Free Queens Coalition, said Sunnyside Community Services is uniquely positioned to increase interest in vaccines due to its active members.
She said when one community member said they were hesitant about the vaccine at a recent town hall, other community members chimed in to explain why they got the shot. One person took the vaccine to make sure a senior citizen they care for is safe, Lopez said, and one mother said they want to make sure their child is cared for.
“For us, the biggest goal is kind of bringing up those voices and those stories of why people decided to take the vaccine so that other people who are so a little bit more hesitant will be able to make those connections as well,” Lopez said.
Anna Kern, a 33-year-old nurse practitioner in Ferndale, Michigan, didn’t expect to get COVID-19 after being vaccinated. She got her shots in January, but then in April, she tested positive after being exposed to the virus through an unvaccinated coworker. She has had chills, fatigue, and a racing heart ever since.
“You feel lots of guilt – like, what did I do wrong? How could I have been more cautious?” Kern told Insider, adding, “It feels weird to be a statistical anomaly.”
Breakthrough infections – cases of COVID-19 diagnosed at least two weeks after someone is fully vaccinated – are indeed rare. Just 0.01% of vaccinated Americans had developed breakthrough infections as of April 30, according to a recent report from the Centers for Disease Control and Prevention. But the CDC data suggests that women represent a majority of these cases: 63%.
That’s consistent with clinical trial data, which suggests that coronavirus vaccines are slightly less effective among women. Pfizer’s COVID-19 vaccine was found to have a 96.4% efficacy rate in men, but 93.7% in women. Its widely cited 95% efficacy rate is an average of those two results.
Moderna’s vaccine, meanwhile, was found to have a 95.4% efficacy rate in men, but 93.1% in women. And Johnson & Johnson’s shot reduced the risk of moderate to severe COVID-19 by 68.8% in men, but 63.4% in women.
Together, these results are “a bit perplexing,” Sabra Klein, co-director of the Johns Hopkins Center for Women’s Health, Sex, and Gender Research, told Insider.
Normally, women mount stronger immune responses to vaccines than men do, which often leads to greater protection. Scientists suspect that higher levels of estrogen play a role in this, since estrogen stimulates the immune system.
Klein has a theory as to why that same pattern isn’t playing out for the coronavirus vaccines: It’s possible the shots might be less effective against coronavirus variants for women than for men. Five “variants of concern” have caused the majority of breakthrough infections in the US.
Vaccines train the body to recognize the original coronavirus identified in Wuhan, so they might still work well against that strain in women.
“The whole basis of vaccination is to have some memory cells so that, should you get infected with the virus, if it’s even possible to get for you to get infected, you would be asymptomatic as opposed to being symptomatic because your immune system’s already been trained,” Klein said. “So it might be that some of that training and the specificity of that training is greater for females than males.”
There are, of course, other possible explanations. More women than men have been vaccinated so far, and women could be more inclined to seek out COVID-19 tests or report their illness if they’re experiencing breakthrough symptoms. Women also represent the majority of healthcare workers, who are regularly screened for coronavirus infections at work. So it’s possible that the vaccines won’t turn out to be less effective among women after all.
But it’s hard to determine the answer, Klein said, without more data on how each sex is responding to vaccines.
“The biological differences between males and females and how this could be playing out in response to these vaccines has really not received adequate attention,” she said. “I definitely don’t think these kinds of things should be ruled out – and that’s often what happens because it’s easier to think this is reporting bias than something real.”
Age could also influence vaccine efficacy in women
Few real-world studies have examined the effectiveness of coronavirus vaccines among men versus women in great detail, so scientists are hesitant to say whether women are more likely to develop breakthrough infections.
“While the overall percent of reported breakthrough infections was higher in women, we do not know the sex-disaggregated numbers for the severity of these infections,” Vaishali Moulton, an assistant professor of medicine at Beth Israel Deaconess Medical Center, told Insider.
Researchers also don’t know whether vaccine effectiveness is particularly low for women in a certain age bracket.
On average, people who have experienced breakthrough infections are between 40 and 74 years old, the CDC report found. Most women undergo menopause between 40 and 60 – so that could partly explain why vaccine efficacy was lower in that group.
“We know that some of the female immunity definitely declines post-menopausally and is associated with a reduction in estrogen,” Klein said.
Since no mRNA vaccine had been authorized before last year, scientists are also considering whether the platform itself might stimulate different immune responses in each sex.
A new study suggests that men and women may respond differently to the lipid molecules that mRNA vaccines use to deliver coded messages to the body. The researchers found that natural killer cells – a type of immune cell that helps fight off infection – absorbed fewer lipid molecules in female blood samples than in male samples.
Klein said it’s important to explore these sex-based differences quickly, since more breakthrough infections could allow the pandemic to stretch on.
“If we don’t have good efficacy of this vaccine in all people, two things are going to happen,” Klein said. “You’re going to have these breakthrough cases and we are not going to be able to really stop the spread as much as we hope we will. You’re also going to start to lose public trust.”
Vaccine trials have a history of focusing on men
Vaccine trials have a long history of focusing on male participants. US trials weren’t legally required to enroll women until 1993, when Congress passed the National Institutes of Health Revitalization Act.
Prior to that, women were often left out of medical research because doctors and scientists were concerned that experimental drugs could pose a health risk to babies if a woman became pregnant during a study. Researchers also worried that women’s fluctuating hormone levels could complicate trial results. In 1997, the Food and Drug Administration even recommended excluding women of reproductive age – as well as women who were single, used contraception, or whose husbands had gotten a vasectomy – from early-stage drug trials.
In general, today’s clinical trials often prefer to enroll women taking birth control due to similar concerns about pregnancy, Klein said. Many early-stage vaccine trials also default to using exclusively male mice to avoid having to factor in hormonal differences between the sexes. But even when female participants are included in trials, Klein said, there’s no requirement that the results be analyzed separately for men and women.
That often means that women don’t receive the ideal vaccine dose: Women only need half the standard dose of the seasonal flu vaccine, for instance, to generate the same amount of protective immunity as men do. As a result, women are more prone to adverse reactions from drugs or vaccines. A report last year found that women experience adverse drug reactions nearly twice as often as men do.
Some of these issues could be playing out now with coronavirus vaccines.
The vaccines’ early-stage trials included female animals, and human trials enrolled a relatively equal share of men and women. But the trials didn’t separate data for the sexes when it came to side effects, and pregnant women were excluded.
“Whether you’re talking about male-female differences, or you’re talking about pregnancy, a lot of this could have started in preclinical studies in order to just test some of these things,” Klein said. “All too often, the dogma is that biological sex isn’t important in this context.”
Real-life data has also revealed that women tend have more severe side effects after their coronavirus shots than men do. A February report found that roughly 79% of instances of vaccine side effects reported to the CDC came from women, though just 61% of doses were administered to women overall.
Women also represent the majority of people who experience adverse reactions to coronavirus vaccines, including rare blood clots and anaphylaxis (a severe allergic reaction).
Still, biologists like Klein are hopeful that vaccine researchers will begin studying female subjects more closely in the near future.
“If there’s one silver lining of the pandemic for people like myself who work in the broader area of women’s health, it’s that it’s finally making it very clear that women’s health extends beyond our reproductive tract and that we really should be studied and compared with men,” she said.