How COVID-19 Mutations in Animals Affect Vaccine Effectiveness in Humans

The importance of commercially raised animals in the COVID-19 pandemic has received a lot of attention in recent weeks, when a new variant of SARS-CoV-2 was detected in farm mink. Unfortunately, minks tend to be relatively susceptible to respiratory infections, and these can easily spread through mink farms due to the high density of housing. Data from the Netherlands before the pandemic have revealed that mink can easily become infected with SARS-CoV-2 and then pass the virus on to humans. In Denmark, 214 people have been infected with a variant of SARS-CoV-2 that is presumed to have mutated in the Danish mink. More than 200 mink farms had tested positive for SARS-CoV-2, and at least five different mink variants of the virus have so far been detected. These events initiated a massive slaughter of farm minks in that country (although this was limited due to problems), and highlighted the disturbing scenario of person-to-mink-to-person transmission of SARS-CoV-2, with the possibility that the virus changes in the mink before reinfecting people. reveals the possibility that the mink could serve as an alternative host to promote SARS-CoV-2 mutations, which can be transmitted to humans and other animals, both domestic and wild, and potentially lead to the wild mustelid (mink, ferrets and related species). ) population at risk We are researchers in the fields of virology, immunology and pathology. Our research programs link human and animal health and study virus transmission, immune responses to viruses, how viruses cause disease, and the development of strategies such as vaccines to prevent infectious diseases. Recent news linking mink to the current pandemic highlights the importance of research at the interface of animal and human health. Since the start of the COVID-19 pandemic, the world has learned a lot about virology, as well as the One Health concept. At the core of One Health is the idea that human and animal health are intertwined in a shared environment, and that we need to broaden our perspectives beyond human health alone. In fact, animals have been at the center of this pandemic from the beginning. The overwhelming evidence suggests that this coronavirus (SARS-CoV-2), which causes COVID-19, originated in bats. There is debate as to whether an intermediate animal host could have harbored additional changes in SARS-CoV-2 to produce the current virus that spreads efficiently from person to person. The main candidate for this is a scaly anteater known as a pangolin.

What is known for sure is that changes in coronaviruses can occur over time due to inherent and deliberate errors in the ability of these viruses to copy their genetic codes. This allows a virus to make small changes over time and is an efficient way to adapt to new environments.One of the recently identified Danish mink strains is of particular concern because changes occurred in the genome in what is called the protein peak of the virus, which it uses to enter human cells. These changes have been detected in 12 human cases related to this particular mink variant. Fortunately, this change does not appear to correlate with worse clinical outcomes, based on a small number of cases. The spike protein is also the primary target of natural and vaccine-induced immune responses to the virus. In theory, if SARS-CoV-2 mutates too much, the immunity derived from the parental virus, acquired by natural infection or vaccination, could become less effective against the new strain. The good news is that, so far, there is no evidence that the mink-derived SARS-CoV-2 mutant can circumvent natural or vaccine-induced immunity. Fortunately, our immune system is designed to generate antibodies against multiple parts of the spike protein. This means that if only a small part of the spike protein is mutated, antibodies against other parts of the protein should still confer at least some protection. The fact that SARS-CoV-2 can change highlights the need for vaccines that not only induce protective antibodies, but can also elicit robust T-cell responses, which is the other main mechanism by which our immune systems can kill viruses. . Like antibodies, T cells will target multiple parts of viral proteins, increasing the chance of maintaining immunity against non-mutated regions of proteins.It might also be important to consider making vaccines that target more than one of the SARS-CoV -2 proteins. It is very difficult for a virus to make major changes to multiple proteins without compromising fitness. The other issue that the SARS-CoV-2 mink brings to the forefront of the vaccine development effort is the need for vaccines that are “plug-and-touch.” These are vaccine technologies in which the viral protein to which The vaccine is designed can easily be swapped with a different version of the viral protein. Once approved by health regulators as safe and effective against a highly pathogenic coronavirus, these technologies could, in theory, be rapidly modified to target emerging mutant viruses ; similar to the annual flu vaccine that is modified each year to target emerging variants of the flu virus. Since mink has recently been confirmed as a possible reservoir for SARS-CoV-2, more research is urgently needed to inform rationally based decisions to eliminate millions of these animals. Even if mass slaughter continues, it is unlikely that mink farms will be fully limit globally in the near future. So the question is how do we handle the potential threat to human health from SARS-CoV-2 in long-term mink? First, improved biosecurity measures must be implemented in mink farms. Second, detection of coronavirus in farm mink should be added. to the surveillance programs of the animal health regulatory agencies, with this information made available to human health regulators. Third, consideration could be given to tailoring COVID-19 vaccines for animal reservoirs, which would now include farmed minks. These recommendations would not only reduce the potential spread of coronavirus from mink to humans, but would also simultaneously address SARS-CoV-2-related health issues for mink. In fact, mink can develop COVID-19 after becoming infected with SARS-CoV-2, and it can sometimes be serious and lethal, without effective current treatment. Unless future evidence suggests otherwise, it may be best to stay the course with current vaccine development. programs with the objective of obtaining the approval of multiple technological platforms for use in humans. These platforms can then easily be modified, similar to the annual flu vaccine, to target emerging mutant viruses, if warranted. Simultaneously, public health agencies with any interest in promoting human health must expand their visions to include the health and surveillance of domestic animals and In the case of SARS-CoV-2, humans are currently the largest reservoir of the disease. viruses on Earth, and the threat of spread from human hosts to farm animals and wildlife species is now becoming apparent. This is an opportune time to take stock of our relationships with animals and the natural world and take steps to ensure the health of all and this biosphere we share.