Despite their enduring association with disease, viruses are a natural product of evolution—organisms that can rapidly change, adapt, and use human cells to replicate. It is this ability that not only causes disease, but also influences the evolution of living systems.
The main task of any virus is to enter a cell and make copies of itself. The immune system keeps a constant stream of microorganisms at bay, and its “memory” allows it to recognize familiar threats even years after vaccination or illness. But viruses also change — and do so faster than most other forms of life.
Experts explain that the ability of viruses to evade the body's defenses is a result of constant mutations, gene exchange, and natural selection. It is these processes that allow pathogens to "learn" and adapt to new conditions.
One mechanism is through mutations—changes in the genetic code—that occur in influenza viruses and coronaviruses. This leads to the emergence of new strains that are able to evade the immune response. Another is through recombination, or reassortment, where viruses mix parts of their genomes in a single cell. This is how the H1N1 strain emerged, which caused a pandemic in 2009.
Selection plays a role. Viruses that attach better to cells, cause milder symptoms, or remain undetected by the body for longer are more likely to spread. This is how the SARS-CoV-2 variant “Omicron” supplanted previous strains — thanks to its high infectiousness and milder early course of the disease.
Scientists emphasize that increasingly often respiratory infections cause minor symptoms at the start - a mild runny nose, fatigue, minimal cough. This is not a coincidence, but the result of evolution, which helps viruses remain "invisible" for longer.
This can be counteracted through a combination of vaccination, early response to the first manifestations of the disease and prevention. Doctors advise not to ignore the symptoms, even if they seem not serious: in the initial stages it is important to reduce the viral load. This is helped by direct-acting antiviral therapy, which blocks the enzymes used by viruses for reproduction. Studies show that drugs based on natural compounds, in particular proteflazid, are able to inhibit replication mechanisms and reduce the risk of complications from influenza, SARS and COVID-19.
Experts also remind people of the basic rules of prevention - hand hygiene, avoiding close contact with sick people, regular ventilation, respiratory etiquette, and self-isolation in the first days of symptoms. These are the steps that break the chain of infection.
Viruses remain a part of the world around us — but understanding the mechanisms of their evolution helps to more effectively control the spread of infections and reduce health risks.
