Three studies have recently been published providing new data on the origin of the COVID-19 pandemic. The studies are reviewed in the scientific journal nature. The literature is reviewed by Professor Dimitrios Paraskevi (Associate Professor of Epidemiology and Preventive Medicine), Theoklis Zaoutis (Professor of Paediatrics and President of EODY) and Thanos Dimopoulos (Rector of EKPA).
In early January 2020, the Uhan market was considered the likely initial source of spread because most people infected with COVID-19 at that time had been in the market before they developed symptoms. To investigate the case, samples were collected from a variety of animals sold there as well as environmental samples such as cage surfaces, vendor stalls and drains to identify the possible source of the pathogen. The results of the study published in March under the auspices of the World Health Organization (WHO) showed that 200 samples collected from animals were negative, but that about 1,000 environmental samples from stalls and other market sites were found to be positive!
In the first study researchers from China, with the cooperation of China's CDC analyzed the genetic material from samples taken from the Huanan market. The study confirms that the SARS-CoV-2 genetic sequences from the market are almost identical to those isolated from humans. They also confirmed that the two groups (lineages A and B) identified in the early stages of the pandemic were also detected in market samples. According to Dr Ray Yip, an epidemiologist and former director of the China CDC, this study confirms that the Wuhan market played an important role in the spread of the virus.
According to the study, the southwestern part of the Wuhan market is the likely epicentre of the coronavirus spread. The researchers also examined the locations of the positive samples collected in the market, as well as information regarding the surroundings of the sites from which the positive samples were collected. One significant finding is the mapping of five positive samples from the market to a stall selling live animals and, more specifically, to a metal cage, and carts used to move animals and a machine used to remove feathers from birds. SARS-CoV-2 was also detected in the sewage from the market.
In the second study, it is reported that the two groups A and B of SARS-CoV-2 are too different from each other to have evolved in humans. Therefore, it is speculated that they have come from independent transmissions from animals to humans over the same period of time.
According to virologist Dr Worobey, all the evidence suggests that the spread started in the marketplace and it is highly unlikely that the two groups (lineages A and B) of the virus could have come from a laboratory and then the infected individuals were coincidentally found in the marketplace. Dr Munster believes that it is not certain that the two groups have come from independent transmission events because the virus could have evolved largely in an immunosuppressed individual.
These studies are important and shed light on the possible origin of the virus considered to be the Wuhan market. It is also important for public health to clarify the exact origin of the virus as well as the practices that led to the infections so that similar actions can be avoided in the future.
Source: ygeiamou.gr
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