Is it true that pangolin transmits the COVID-19 coronavirus? If so, does this have important consequences in the management of this disease? Let’s see that in this article.
Right now, the scientific community is trying to determine whether the pangolin transmits the COVID-19 coronavirus or not. It is important to note that coronaviruses (CoV) have been well known to veterinary virologists for decades.
Generally, coronaviruses affect birds and mammals in a species-specific way. Thus, specific strains of coronaviruses are known to infect humans, cats, dogs, rodents, rabbits, ferrets, cows, turkeys and pigs.
In this article, we will briefly summarize what we know about COVID-19 so far.
Coronaviruses and infection in humans
Coronaviruses were first identified in the late 1960s. Since then, 4 CoVs have been identified that can infect humans (HCoV), and cause mild, mild infections, such as the common cold.
Curiously, these 4 low pathogenic HCoVs are also linked to the coronaviruses which affect animals. According to several studies which have analyzed the genomic sequences currently available, the following natural hosts have been attributed to these animal species:
- HCoV-HKU1: natural rodent
- HCoV-NL63: natural bat
- HCoV-OC43: natural rodent: intermediate to livestock
- HCoV-229E: natural bat: intermediate to alpacas
Highly pathogenic coronavirus for humans
Until 2002-2003, Cov was not considered to be highly pathogenic to humans. At that time, an epidemic of severe acute respiratory syndrome coronavirus (SARS-CoV) occurred in Guangdong province, China. This virus has spread worldwide.
Later, in 2012, another highly pathogenic coronavirus, the Middle East respiratory syndrome coronavirus (MERS-CoV) appeared in Saudi Arabia and other countries in the Middle East. In both cases, the virus is believed to have originated from bats . In addition, evidence has indicated that these species are their intermediate hosts:
It is because of these two precedents that the hypothesis according to which COVID-19 could also be of animal origin is born. Indeed, analyzes of genomic sequences confirm that COVID-19 also comes from bats. However, its intermediate host is not yet known.
If pangolin is the intermediate host for COVID-19, what does this mean?
Normally, viruses are spread between animals of the same species. Sometimes they can cross or “mix” and cause disease in another species.
It is also important to know that viruses can be transmitted from animals to humans in two main forms:
- Directly from the natural host or from its secretions contaminated by the virus
- Through another organism that functions as an intermediate host
It should be noted that the genes of viruses are separated into segments. Thus, the segmented genome allows viruses of different species to mix or recombine to create a new virus . In these cases, it is common for viruses of two separate species to infect the same person or animal at the same time. This is called co-infection.