health care
Breakthrough Infections Occur in Those with Lower Antibody Levels, Israeli Study Shows
Posted on by Dr. Francis Collins
To see how COVID-19 vaccines are working in the real world, Israel has provided particularly compelling data. The fact that Israel is relatively small, keeps comprehensive medical records, and has a high vaccination rate with a single vaccine (Pfizer) has contributed to its robust data collection. Now, a new Israeli study offers some insight into those relatively uncommon breakthrough infections. It confirms that breakthrough cases, as might be expected, arise most often in individuals with lower levels of neutralizing antibodies.
The findings reported in The New England Journal of Medicine focused on nearly 1,500 of about 11,500 fully vaccinated health care workers at Sheba Medical Center, Ramat Gan, Israel [1]. All had received two doses of the Pfizer mRNA vaccine. But, from December 19, 2020 to April 28, 2021, they were tested for a breakthrough infection due to a known exposure to someone with COVID-19 or possible symptoms of the disease.
Just 39 confirmed breakthrough cases were found, indicating a breakthrough infection rate of just 0.4 percent. That’s consistent with rates reported in previous studies. Most in the Israeli study who tested positive for COVID-19 had mild or no symptoms and none required hospitalization.
In the new study, researchers led by Gili Regev-Yochay at Sheba Medical Center’s Infection Control and Prevention Unit, characterized as many breakthrough infections as possible among the health care workers. Almost half of the infections involved members of the hospital nursing staff. But breakthrough cases also were found in hospital administration, maintenance workers, doctors, and other health professionals.
The average age of someone with a breakthrough infection was 42, and it’s notable that only one person was known to have a weakened immune system. The most common symptoms were respiratory congestion, muscle aches (myalgia), and loss of smell or taste. Most didn’t develop a fever. At six weeks after diagnosis, 19 percent reported having symptoms of Long COVID syndrome, including prolonged loss of smell, persistent cough, weakness, and fatigue. About a quarter stayed home from work for longer than the required 10 days, and one had yet to return to work at six weeks.
For 22 of the 39 people with a breakthrough infection, the researchers had results of neutralizing antibody tests from the week leading up to their positive COVID-19 test result. To look for patterns in the antibody data, they matched those individuals to 104 uninfected people for whom they also had antibody test results. These data showed that those with a breakthrough infection had consistently lower levels of neutralizing antibodies circulating in their bloodstream to SARS-CoV-2, the coronavirus that causes COVID-19. In general, higher levels of neutralizing antibodies are associated with greater protection and lower infectivity—though other aspects of the immune system (memory B cells and cell-mediated immunity) also contribute.
Importantly, in all cases for which there were relevant data, the source of the breakthrough infection was thought to be an unvaccinated person. In fact, more than half of those who developed a breakthrough infection appeared to have become infected from an unvaccinated member of their own household.
Other cases were suspected to arise from exposure to an unvaccinated coworker or patient. Contact tracing found no evidence that any of the 39 health care workers with a breakthrough infection passed it on to anyone else.
The findings add to evidence that full vaccination and associated immunity offer good protection against SARS-CoV-2 infection and severe illness. Understanding how SARS-CoV-2 immunity changes over time is key for charting the course of this pandemic and making important decisions about COVID-19 vaccine boosters.
Many questions remain. For instance, it’s not clear from the study whether lower neutralizing antibodies in those with breakthrough cases reflect waning immunity or, for reasons we don’t yet understand, those individuals may have had a more limited immune response to the vaccine. Also, this study was conducted before the Delta variant became dominant in Israel (and now in the whole world).
Overall, these findings provide more reassurance that these vaccines are extremely effective. Breakthrough infections, while they can and do occur, are a relatively uncommon event. Here in the U.S., the Centers for Disease Control and Prevention (CDC) has recently estimated that infection is six times less likely for vaccinated than unvaccinated persons [2]. That those with immunity tend to have mild or no symptoms if they do develop a breakthrough case, however, is a reminder that these cases could easily be missed, and they could put vulnerable populations at greater risk. It’s yet another reason for all those who can to get themselves vaccinated as soon as possible or consider a booster shot when they become eligible.
References:
[1] Covid-19 breakthrough infections in vaccinated health care workers. Bergwerk M, Gonen T, Lustig Y, Amit S, Lipsitch M, Cohen C, Mandelboim M, Levin EG, Rubin C, Indenbaum V, Tal I, Zavitan M, Zuckerman N, Bar-Chaim A, Kreiss Y, Regev-Yochay G. N Engl J Med. 2021 Oct 14;385(16):1474-1484.
[2] Rates of COVID-19 cases and deaths by vaccination status, COVID Data Tracker, Centers for Disease and Prevention. Accessed October 25, 2021.
Links:
COVID-19 Research (NIH)
Sheba Medical Center (Ramat Gan, Israel)
Preeclampsia: Study Highlights Need for More Effective Treatment, Prevention
Posted on by Dr. Francis Collins
Thinkstock
It’s well known that preeclampsia, a condition characterized by a progressive rise in a pregnant woman’s blood pressure and appearance of protein in the urine, can have negative, even life-threatening impacts on the health of both mother and baby. Now, NIH-funded researchers have documented that preeclampsia is also taking a very high toll on our nation’s economic well-being. In fact, their calculations show that, in 2012 alone, preeclampsia-related care cost the U.S. health care system more than $2 billion.
These findings are especially noteworthy because preeclampsia rates in the United States have been steadily rising over the past 30 years, fueled in part by increases in average maternal age and weight. This highlights the urgent need for more research to develop new and more effective strategies to protect the health of all mothers and their babies.
Portable System Uses Light to Diagnose Bacterial Infections Faster
Posted on by Dr. Francis Collins
Caption: PAD system. Left, four optical testing cubes (blue and white) stacked on the electronic base station (white with initials); right, a smartphone with a special app to receive test results transmitted by the electronic base station.
Credit: Park et al. Sci. Adv. 2016
Every year, hundreds of thousands of Americans acquire potentially life-threatening bacterial infections while in the hospital, nursing home, or other health-care settings [1]. Such infections can be caused by a variety of bacteria, which may respond quite differently to different antibiotics. To match a patient with the most appropriate antibiotic therapy, it’s crucial to determine as quickly as possible what type of bacteria is causing his or her infection. In an effort to improve that process, an NIH-funded team is working to develop a point-of-care system and smartphone app aimed at diagnosing bacterial infections in a faster, more cost-effective manner.
The portable new system, described recently in the journal Science Advances, uses a novel light-based method for detecting telltale genetic sequences from bacteria in bodily fluids, such as blood, urine, or drainage from a skin abscess. Testing takes place within small, optical cubes that, when placed on an electronic base station, deliver test results within a couple of hours via a simple readout sent directly to a smartphone [2]. When the system was tested on clinical samples from a small number of hospitalized patients, researchers found that not only did it diagnose bacterial infections about as accurately and more swiftly than current methods, but it was also cheaper. This new system can potentially also be used to test for the presence of antibiotic-resistant bacteria and contamination of medical devices.
Taking Control: Learn More About Accessing Your Health Information
Posted on by Dr. Francis Collins
Credit: Lydia Polimeni, NIH
Usually, I share cool science advances and major medical breakthroughs on this blog. But, today, I’d like to share something a little different, something of great importance for both your health and the advancement of biomedical research: new guidelines on how you can access your own health information.
The Health Insurance Portability and Accountability Act of 1996 (HIPAA) Privacy Rule has long supported the right of individuals to request and obtain copies of their medical records and other health information maintained by health-care professionals, medical facilities, and health insurance plans. However, due to the increasing use of online health-information technology and growing interest among Americans in being active participants in health-related decisions, the U.S. Department of Health and Human Services (HHS) recently issued much-anticipated guidance that serves to answer common questions and clarify key issues regarding access to health information under HIPAA. Think of it as a valuable personal roadmap for navigating a part of health care that is all-too-often confusing and frustrating!
Among the many reasons that people need easy, affordable access to their health records is to empower them to take more control over decisions regarding their health. Such information can help individuals improve their ability to monitor chronic conditions, stick with treatment plans, track progress in wellness programs, and identify and correct erroneous information. In addition, some people may want such access so they can directly contribute their health information to biomedical research projects. One such endeavor is the new, NIH-led Precision Medicine Initiative Cohort, in which 1 million or more volunteers will agree to share data, including information from their health records. Maintaining the security and privacy of individual information will be of paramount importance. In return, participants will have the highest levels of access to their study results, along with summarized results from across the cohort.
Creative Minds: Lessons from Halfway Around the Globe
Posted on by Dr. Francis Collins
Caption: Duncan Maru (right) and Community Health Director Ashma Baruwal (left) evaluating a patient in rural Nepal.
Credit: Allison Shelley
A decade ago, as a medical student doing volunteer work at a hospital in India’s capital of New Delhi, Duncan Maru saw a young patient who changed the course of his career: a 12-year-old boy in a coma caused by advanced tuberculosis (TB). Although the child had been experiencing TB symptoms for four months, he was simply given routine antibiotics and didn’t receive the right drugs until his parents traveled hundreds of miles at considerable expense to bring him to a major hospital. After five weeks of intensive treatment, the boy regained consciousness and he was able to walk and talk again.
That’s quite an inspiring story. But it’s also a story that haunted Maru because he knew that if this boy had access to good primary care at the local level, his condition probably never would have become so critical. Determined to help other children and families in similar situations, Maru has gone on to dedicate himself to developing innovative ways of providing high-quality, low-cost health care in developing areas of the world. His “lab” for testing these efforts? The South Asian nation of Nepal—specifically, the poverty-stricken, rural district of Achham, which is located several hundred miles west of the national capital of Kathmandu.
