Originating from the original Wuhan, Vietnam has so far recorded four nCoV strains including British, South African, African Rwanda and one G mutant.
Covid-19 first appeared on December 31, 2019, in Wuhan city, Hubei province, central China. The first patients were all buyers and sellers at the Huanan Seafood Market. It is caused by a completely new strain of the corona virus, called nCoV, before being named SARS-COV2 by the World Health Organization.
Then, nCoV quickly spread to many countries around the world. Viruses have the genetic code of RNA, which easily mutates and creates new strains from the original strain. The most recent are the new strains from the UK and from South Africa that are thought to be 70% more transmissible than the known strains, which are currently circulating around the world. Race from Rwanda is less common, not much is known about it currently.
In Vietnam, these three strains have appeared, including:
Variants from England
On the morning of January 2, the Ministry of Health announced the first case of British strain infection in Vietnam as “patient 1435”. 45-year-old woman, from Tra Vinh, imported from England on December 22, 2020
Patients concurrently infected with the British variant nCoV strain VOC 202012/01 and mutant D614G, another strain from the Wuhan original nCoV strain. This case was confirmed by health officials not likely to spread in the community, because of isolation upon arrival.
The British strain was first discovered in Kent, southeast England, in September 2020, including many variants. According to the scientists, the new variant of nCoV is capable of transmitting 70% faster and more powerful than previous strains, there is no basis to show higher virulence at the time of the study.
The epidemic at the end of January so far in Hai Duong and Quang Ninh, the source of the infection is unknown, but all are caused by the nCoV Anh strain, Health Minister Nguyen Thanh Long affirmed at the Government’s online meeting with 63 provinces and cities about socio-economic picture in January, February morning.
Doctor Nguyen Trung Cap, deputy director of National Hospital for Tropical Diseases, said that the new strain is transmitted through the air, including via aerosol and through nuclear droplets. Dried droplets will become nuclear droplets flying through the air.
Through monitoring the progress of the disease of 165 Covid-19 patients at the No. 1 Field Hospital in Chi Linh City, Hai Duong, Dr. Thu said “it seems” that the British variant caused lung damage earlier than the period. previous paragraph.
According to Dr. Le Quoc Hung, Head of the Department of Tropical Diseases, Cho Ray Hospital, new studies, increasing the virulence of the British strain by about 30%, the ability to infect 70% higher than the old strain. “The Northern provinces are in a cold season, which will lead to longer survival of the virus in the environment than when the weather is hot in the Central region,” said Dr. Hung.
In Ho Chi Minh City, “patient 1660”, 28 years old, from Hai Duong, after having been sequenced at the Hospital for Tropical Diseases, also showed British strains infected results.
Variant of South Africa
The Central Institute of Hygiene and Epidemiology announced the results of genetic sequencing “patient 1442”, 25 years old, a South African national, infected with the new nCoV variant from South Africa. This is the first case of South African infection in our country. This patient was quarantined upon entry.
The South African variant (501.V2 or B.1.351) was first discovered in the Nelson Mandela Bay area in October. Some studies indicate that it has appeared and circulated since August, after that. spread throughout the region, including Cape Town – a popular tourist destination. The variant quickly spread across Africa, found in at least 24 countries outside the continent.
Scientists around the world rated the nCoV variant in South Africa more worrying than the nCoV variant from the UK due to its rapid spread and possibly evasion of the vaccine.
Variant of Rwanda, Africa
On January 12, the HCM City Center for Disease Control (HCDC) announced the results of genetic sequencing of nasopharyngeal fluid samples “patient 1979” and two patients from the loading team at Tan Son Nhat airport showed that they belong strain A.23.1 in Rwanda, Africa.
The study was conducted by the Hospital for Tropical Diseases of Ho Chi Minh City in collaboration with the Oxford University Clinical Research Unit (OUCRU).
Through analysis, the three genomes of the patient above have the similarity over 99.95%. Thus, the infectious cluster of “patient 1979” and the loading nest patients is more likely to originate from one source of transmission.
This strain is the first time in Vietnam and Southeast Asia. HCDC confirmed that this strain is not the British strain causing epidemic in Hai Duong, Quang Ninh; nor is it a South African strain.
The nCoV strain of group A.23.1 was first detected in Rwanda, Africa around the end of the third week of October 2020. In addition to Rwanda, A.23.1 has only been discovered in a few other countries around the world, including the United States, United Arab Emirates, Australia, Great Britain, and Denmark. However, there have been no signs of unusual developments in these countries.
Besides, epidemic in Da Nang, Starting in late July, the World Health Organization (WHO) said that the nCoV strain detected in Da Nang is similar to the strains circulating in many countries.
At that time, the nCoV mutation was most widely spread in the world called D614G. This non-new strain of strain, commonly known as the G-type, has appeared sporadically in patient specimens of nCoV-infected people from the onset of the epidemic in Wuhan until February 2020. However, when entering the US and European countries, the G-body increased rapidly.
At the end of July 2020 analysis, strain D614G existed in more than 70% of confirmed infections worldwide, nearly 100% in Europe. This mutation of CoV is highly contagious, with constant toxicity.
As of February 12, Vietnam recorded 2,140 cases of nCoV infection. Of which, 1,528 people have recovered from the disease, 35 cases died. 573 people are being treated, including patients involved in the outbreak from Hai Duong, Quang Ninh, Tan Son Nhat airport and immigration cases.