Delay the second dose of Covid vaccine, at least for people under the age of 65, could reduce the mortality up to 20%, but only in certain situations. This is what one reveals US study Published on “The BMJ”. If there are some conditions, such as vaccine efficacy at a dose of 80% or greater and vaccination rates of 0.1% to 0.3% of the population per day, the first dose could prevent between 47 and 26 deaths per 100,000 individuals, respectively. Both Pfizer and Moderna, in a two-dose program, are able to ward off severe symptomatic infections and death. However theimmunity worldwide it remains low also due to the low number of vaccinations.
The longer it takes to effectively vaccinate the world’s population against Covid, the greater the risk of it developing resistant strains. This fact has prompted health authorities to prioritize the first dose to be administered to as many people as possible, even if it means delaying the second dose beyond the required period of time. The justification is based on the assumption that a protection significant against Covid can be obtained after a single dose. To investigate this further, a team of scientists measured the impact of delayed second dose vaccine policies on infections, on hospitalizations hospital and deaths compared to the current vaccination regimen.
A simulation model based on a sample population of 100,000 US adults and a series of scenarios were created in order to predict potentially infectious interactions under different conditions over a period of 6 months. These included varying levels of effectiveness the vaccine, administration rates and hypothesis on the fact that the same prevents the transmission and worrying symptoms or only severe manifestations, including death. The researchers also looked at the impact of delaying the second dose for people younger than 65, but not before fully vaccinating older people. The results suggest that, under specific conditions, a decrease in cumulative mortality, infections and hospital admissions can be achieved when the second dose is delayed.
The scholars then replicated the simulations several times, using the data to estimate outcomes at different population levels. The latter analysis found that delaying the second dose is optimal for daily vaccination rates of 0.3% or less if the effectiveness of the first dose is 80% or greater. Furthermore the strategy the delayed second dose for individuals under the age of 65 worked well with all vaccination rates tested, resulting in a reduction in absolute cumulative mortality to approximately 48 subjects per 100,000 people. According to the scientists, these results could be very important for the vaccination campaign and for the lotta against Covid.