Virus variants—do we have anything to fear?
While it seemed that the COVID-19 pandemic would soon be a thing of the past and the world would return to normal, the reality turns out to be less rosy. One of the reasons for this is the emergence of new variants of the SARS-CoV virus resulting from mutations. Is there an end in sight for these mutations, and is there any way we can protect ourselves from them?
It’s dead, but it’s still infectious—how is that possible?
Viruses are complex organic molecules composed of proteins (which form the viral envelope, or capsid) and nucleic acids—RNA or DNA (which constitute the genetic material). They exhibit characteristics of both inanimate matter and living cellular organisms. Individual complete viral particles—virions—use living organisms to replicate, infecting their cells by inserting their own nucleic acid into the host’s DNA. Subsequently, during the replication process within the infected cell, the virus’s DNA or RNA is duplicated; when combined with proteins, this forms progeny viruses. These are capable of infecting further host cells, utilizing cellular processes that allow them to cross cell membranes, move within the cell, enter and exit the nucleus, leading to cell death. Viruses belong to the group of obligate parasites, which means they are completely dependent on the host. Outside the host organism, they show no activity—they are dead particles.
The vast majority of viruses target specific types of living organisms (bacteria, plants, animals, humans) and specific types of host cells (e.g., liver cells, epithelial cells) that allow them to penetrate—for it is only within these cells that they are able to replicate. For this reason, viruses that parasitize a specific type of organism or a specific animal species usually do not attack the cells of other organisms and species—if this does happen, it is usually the result of a mutation.
Endless mutations
Mutations involve sudden, abrupt changes in the sequence of an organism’s genetic code, i.e., RNA or DNA. Such a change has specific consequences—the virus undergoes a transformation, and the resulting mutation is either beneficial, giving it an advantage (e.g., allowing it to spread more quickly and persist longer in the host organism), or detrimental, hindering the virus’s survival. If a given mutation benefits the virus, the mutated sequence is retained and replicated during the replication process, while virions with a disadvantageous mutation do not spread further and die out—viruses also undergo natural selection. Consequently, most mutations are rejected.
Susceptibility to mutation depends mainly on the type of nucleic acids in the virions. DNA-containing viruses are more stable and have a lower mutation rate—approximately one event per million. Viruses containing genetic material in the form of RNA are significantly more prone to mutations—in their case, sudden, abrupt changes occur at a rate of one event per thousand.
Viruses whose genetic material is DNA include, among others, HPV and VARV (smallpox virus—the disease it causes was completely eradicated in 1980). RNA viruses, on the other hand, include HIV and influenza, which have very high mutation rates, allowing them to evolve rapidly. This results, for example, in drug resistance in the case of HIV or the need for annual updates to the flu vaccine.
SARS-CoV‑2 – a new member of the mutant family
SARS-CoV‑2 belongs to the group of RNA viruses, and thus to those that mutate more rapidly. During the formation of each complete viral particle, approximately 29 changes occur in the genetic code sequence, i.e., mutations. Despite being an RNA virus, SARS-CoV‑2 is more stable than others in this group and does not mutate as quickly as, for example, the influenza virus. Coronaviruses have an error-correction system that addresses errors arising during replication, which slows the rate of changes within them. However, from time to time, particles emerge that contain several or a dozen or so mutations that increase the virus’s infectivity and virulence—these are the beginnings of a new variant.
How to protect yourself from mutant viruses?
Viruses have mutated, are mutating, and will continue to mutate; there is no cure for this. We can therefore expect further variants of the SARS-CoV-2 virus. However, there is a way to reduce this risk—by curbing the spread of the virus within the population. Mutations occur within the host organism—it depends on the measures taken by potential carriers to prevent further transmission of the virus whether it will find another place to multiply. This may result in the emergence of another change in the genetic sequence.
Covering your mouth and nose, especially when you’re feeling unwell, and disinfecting your hands and surfaces—these are basic measures that require little effort but help protect us and others. These are not unfounded recommendations—when followed as directed, they effectively limit the transmission of the virus. Above all, the hand sanitizers we use should have a good formulation that effectively removes harmful microorganisms while maintaining a pH neutral to the skin (pH: 4–6). It is worth checking whether the formula contains allergens, artificial dyes, or harmful compounds such as chlorides or triclosan, and whether the product has been dermatologically tested. The formula of hand sanitizers should be based on ethyl or isopropyl alcohol (with a concentration between 60% and 75%). Hand washing and/or sanitizing should be performed thoroughly—including the spaces between the fingers—and last at least 30 seconds. One should also not forget to disinfect shared objects and surfaces (e.g., doorknobs, handrails, handles) or products brought home from the store.
Vaccination is also one of the most effective ways to limit the transmission of SARS-CoV-2. Studies show that even if vaccinated individuals become infected, they have a lower viral load in their bodies, which results in fewer mutations.
Even these preventive measures will be of little use if we do not maintain a healthy lifestyle and follow basic safety guidelines. A weakened immune system is unable to adequately defend itself against infection. It is therefore important to ensure adequate sleep, a balanced diet rich in vitamins and minerals (primarily vitamins B, C, D, and E, folic acid, iron, selenium, and zinc), as well as regular physical activity. Social distancing is also key, meaning avoiding crowded places where the risk of virus transmission increases significantly.
Following these recommendations is the only way to limit the virus’s ability to mutate, thereby making mutant viruses less dangerous.
For more information on infection prevention, visit www.medisept.pl
