Research recently showed the efficacy of the COVID-19 mRNA vaccine, even just a single dose, in the reduction of symptom duration.
A News-Medical.net report specified that a study of health workers administered the initial dose of BNT162b2 vaccine in Italy found that they had reduced symptoms and quicker viral clearance even within six days of administering the vaccine.
A lot of vaccines are currently being administered globally in the fight against COVID-19. One of these vaccines is an mRNA vaccine that Pfizer-BioNTech developed.
Essentially, the BNT162b2 vaccine contains a lipid nanoparticle that has an RNA that encodes the spike protein of the severe acute respiratory syndrome coronavirus 2 or SARS-CoV-2. This particular vaccine is given intramuscularly in two doses.
Single-Dose Vaccine Efficacy
Most COVID-19 vaccines are administered in two doses, although there is some evidence that even a single dose can provide some shield against asymptomatic infection.
In Italy, vaccination began in December last year, with the first doses given to identified priority groups. In addition, scientists from the country examined the effect of a single dose of COVID-19 mRNA vaccine on symptom duration and clearance of the virus in healthcare workers.
Results of the study, "First Dose of the BNT162b2 mRNA COVID-19 Vaccine Reduces Symptom Duration and Viral Clearance in Healthcare Workers," were published in the Vaccines journal.
The research team examined routinely gathered data for healthcare workers who were vaccinated from December 2020 to February 2021.
As a result, they were able to identify documented cases of COVID-19 infection, symptom types, duration of symptoms, and the time it took for the virus to clear.
Shorter Virus Duration, Faster Viral Clearance
During the vaccine's first dose of administration, 18 healthcare workers tested positive with the virus within 12 days of vaccination, and half of them exhibited symptoms.
Providing the healthcare workers with their first dose of the COVID-19 vaccine reduced the symptom duration and the viral clearance within six days of administration.
Since the median time of SARS-CoV-2 is roughly five to six days, the infections possibly took place just around the time of vaccination.
Five tested positive between 13 and 21 days of being given the first dose, and roughly 40 percent of them exhibited symptoms. The presence of symptoms and viral clearance was quite shorter in such a case.
Consequently, even a single dose of the vaccine is effective in reducing COVID-19 symptoms and clearance of the virus in health care workers vaccinated for below six days.
Even though the results show the benefit of even a single dose of the mRNA vaccine as explained in the Centers for Disease Control and Prevention site, the study investigators emphasize certain limitations, including a low number of specimens obtained, making the statistical evaluation of lower quality.
Addressing Vaccine Shortage
With vaccine shortage in some European countries, strategies are currently being considered to defer the second dose to offer at least partial protection to a greater fraction of the population.
Nevertheless, there is the risk of incomplete protection, particularly for those at high risk of COVID-19 infection.
The study findings indicate that a single dose of the vaccine lessens symptoms and the time for viral clearance, which suggests a high impact of even one dose of the jab.
Since a shorter symptom duration and the time to decrease viral loads can lessen the transmission of the virus, providing a single dose of the vaccine can substantially reduce the spread.
Nonetheless, reduced symptoms and a rapid decrease in viral load can result in the undercounting of a number of asymptomatic people, who form a substantial proportion in the transmission of COVID-19.
This makes it essential to examine a shift to potential asymptomatic infection after just one dose of the COVID-19 vaccine.
Related information about the efficacy of single dose COVID-19 vaccine is shown on CBC News' YouTube video below:
Check out more news and information on COVID-19 and Vaccines in Science Times.
