Since the onset of the covid pandemic, it has become apparent that there is a great deal of heterogeneity in the transmission of the virus that is worth paying attention to.
This means that not all patients transmit the virus to the same extent, but there are also biological factors that determine this differentiation. Professor at the School of Medicine of the Athens National University. Kapodistrias Gikas Mallorkinis and Thanos Dimopoulos (Rector of EKPA) state that a widely discussed hypothesis is viral load, that is, the amount of virus in the upper respiratory tract (nasopharynx).
What do viral load measurements show?
Viral load is an important indicator and also characterizes the severity of the disease and is widely used in diagnostics (including AIDS). In this case, of course, the viral load in the blood indicates how infectious the patient is, while the levels after the first phase of infection indicate how quickly the disease will progress.
However, unlike blood viral load, measuring it in nasopharyngeal samples presents many challenges. It is difficult at first to compare samples collected in different ways. Unlike blood sampling, the collection of samples from the upper respiratory tract varies widely in the collection of biological material.
Another major problem is that the amount of virus (SARS-CoV-2) shed by patients at different stages of the disease changes dramatically over the course of several hours and from day to day. Typically, on the same day in a patient sample, the mass / amount of virus can increase by a factor of millions.
The interval transmitted by the vaccinated is much shorter
A recent publication in the prestigious New England Journal of Medicine presents for the first time data that account for and control variations in viral load in patients. This was made possible by re-sampling volunteers who were monitored for a long time before they got sick.
The most interesting element came up when comparing the viral load graphs between vaccinated and unvaccinated people. In this case, the difference was characteristic and significant, which made it possible to conclude that the time of transmission of the virus by the vaccinated was much shorter.