September 24, 2021 by John Fernandez
COVID-19 Roundup: U.S. Testing Booster Shots; New Review of Long-Haul Symptoms; and Latest on Antibodies
U.S. Launches Clinical Trial to Test COVID Vaccine Booster Shots
The U.S. government’s National Institutes of Health (NIH) has started a clinical trial during which adults who are fully vaccinated against COVID-19 get booster shots of different existing vaccines to determine the safety of “mixed boosted regimens.”
The trial will initially involve 150 adults who have received one of the three COVID vaccines available under the U.S. Food and Drug Administration’s emergency use authorization: Pfizer-BioNTech, Moderna and Johnson & Johnson.
According to the NIH, each vaccine group will enroll about 25 people, ages 18 through 55 years, and approximately 25 people age 56 years and older. Twelve to 20 weeks following their initial vaccination regimen, participants will receive a single booster dose of the Moderna COVID-19 vaccine as part of the trial.
“All trial participants will be followed for one year after receiving their last vaccination as part of the study,” the NIH states in a news release. “They will be asked to complete telephone check-ins and various in-person follow up visits. Trial investigators will evaluate participants for safety and any side effects post-vaccination.”
Participants also will be asked to provide blood samples so that investigators can evaluate immune responses against current circulating strains of COVID-19, or variants.
The National Institute of Allergy and Infectious Diseases (NIAID), part of NIH, is leading and funding the study.
Although the vaccines currently authorized by the U.S. Food and Drug Administration offer strong protection against COVID-19, we need to prepare for the possibility of needing booster shots to counter waning immunity and to keep pace with an evolving virus,” said NIAID Director Anthony S. Fauci, M.D. “The results of this trial are intended to inform public health policy decisions on the potential use of mixed vaccine schedules should booster doses be indicated.”
Review: 73% of COVID Patients With Moderate-to-Severe Illness Carry Long-Haul Symptoms
Nearly three-quarters — or 73 percent — of patients who initially experienced moderate-to-severe COVID-19 had at least one long-term or “long haul” symptom, says an analysis published in JAMA Network Open.
Researchers from Stanford University reviewed 45 studies that followed 9,751 patients in the months after their initial COVID-19 infections. The results: 73 percent of the patients had at least one symptom 60 days after diagnosis, symptom onset or hospitalization. The findings were similar in studies that followed coronavirus patients for up to six months.
The most common long-haul symptoms, researchers said: fatigue (40 percent), shortness of breath (36 percent); and inability to concentrate, or brain fog, (25 percent).
“This systematic review found that COVID-19 symptoms commonly persisted beyond the acute phase of infection, with implications for health-associated functioning and quality of life,” the study’s co-authors stated. However, more studies are needed to determine symptom duration after longer time-frames, they added.
Tahmina Nasserie, a Ph.D. candidate in epidemiology and population health at Stanford University, and the lead author of the study, told CNN: “We want people to understand that these are mainly hospitalized so we can only generalize our findings for that particular population.” She added that researchers don’t want to “cause a lot of alarm with the value of 73 percent” with long-term systems. “We had no data on individuals who got Covid-19 and simply went about their day,” she said.
Labcorp Study: Antibodies in COVID-Infected Persons Present 10 Months After Infection
In what researchers call a “promising sign,” a new study by the national clinical laboratory, LabCorp, found that nearly 87 percent of naturally infected COVID-19 patients maintained antibodies to the coronavirus for at least 10 months.
The analysis by Labcorp scientists included specimens collected from 39,086 individuals with COVID-19 and tested between March 2020 and January 2021. By using various techniques, Labcorp was able to map rates of antibody positivity, as well as the correlation of a person’s age and sex on antibody status.
Individuals under the age of 65 showed a more sustained rate of positive antibody results, meaning those 65 and older may have increased difficulty maintaining antibodies for a prolonged period of time.
There was no statistically significant difference in spike antibody positivity rates between males and females over time.
“This is good news for naturally infected individuals, and potentially for those who have been vaccinated,” stated Brian Caveney, M.D., chief medical officer and president of Labcorp Diagnostics, in a news release. “More research must be done to understand what type and level of antibodies suggest protection from reinfection. But the prolonged presence of certain antibodies is a promising sign as we continue thinking about safely emerging from the pandemic, as well as future vaccinations and the timing of booster shots.”
According to Labcorp, notable findings from the study include the following:
- While sample sizes varied each day after a positive COVID-19 test, the antibody positivity rate to the coronavirus’ spike protein remained mostly stable for the U.S. population through 300 days (about 10 months) after the initial test.
- The positivity rate of antibodies to the nucleocapsid protein — a coronavirus component that is more active during early infection — declined more rapidly than the rate of spike antibodies, but remained above 60 percent through 10 months of testing.