Just one virus molecule is enough to cause infectious disease

Can exposure to a viral molecule make you infected? Until now, we still do not have enough solid evidence. Larval studies conducted by Wageningen University and Simon Fraser University in Canada have demonstrated that only one virus element is theoretically sufficient to cause transmission and disease.

Viral populations are usually made up of a combination of variations in the virus molecule. To study areas where viral molecules can cause independent infection from one person to another, scientists have done an experiment with two available 'marked' virus variants. They will report the virus population on two experiments (caterpillars).

The experiment showed that exposure to a small amount of virus molecules would cause spread spread in small quantities (20%). Most of the subjects (86%) were suddenly infected by the genotype virus. Conversely, if exposed to more virus, most subjects (99%) will be infected, but most subjects are infected by both viruses. Only 14% are affected by only one of the two variants.

Electron microscopy (SEM) revealed the appearance of SARS-CoV (coronavirus) molecule (in the shape of an arrow). Recent studies have shown that a theoretically viral molecule is sufficient to cause transmission and disease. (Photo: Dr. Mary Ng Mah Lee).

Based on the assumption that every virus molecule operates independently of other virus molecules, the researchers built a feasible sample. This pattern can predict how many virus molecules cause infection and how many different genetic viruses exist in the infected subject, such as plants, insects and humans.The result of this transmission experiment coincides with the conclusion in the sample prediction. From this we can draw the conclusion that virus molecules have independent effects, in fact they can cause more serious infection or disease.

If only a few types of virus molecules can cause infection, the number of virus molecules determines the level of abundance that can be expressed in the body. This is a very important finding because of the interplay of variations, such as competition and exchange of genetic information, determining the progression of the disease and the evolution of the virus.

Until now, things have not been clear about whether a virus can be considered as an independent individual affecting the subject independently, or whether a cluster of viruses combine to cause this infection. This is yet to be sure if viruses affecting humans can work separately, but the study wants to show that it is possible.