What is delta virus?
Delta virus generally refers to Delta virus (the first COVID-19 variant found in India).
Delta is a mutant of COVID-19. It was first discovered in India in June 2020. In May, 20021,WHO named COVID-19 mutant B. 1.6 17.2, which was first discovered in India, as "Delta" mutant. This mutation was identified as one of the driving factors of the second wave of epidemic in India.
On June 5th, 20021,it was reported that the "Delta" variant was further mutated into "Delta+" or "AY. 1" variant. On July 2nd, WHO held a regular press conference in COVID-19. WHO Director-General Tan Desai said that in many countries, Delta mutant is becoming the main epidemic strain. Delta variants have appeared in at least 98 countries and regions, and continue to mutate and evolve. On September 15, Zhong Nanshan and other teams accurately described the Delta transmission chain for the first time. This study revealed that Delta mutant has the characteristics of short incubation period, fast transmission speed, high viral load, long negative time of nucleic acid and easy to develop into critical disease.
Up to September 22nd, 20021year, 185 countries and regions have been infected with the δ mutant.
65438+February 1 1, the press conference of the State Council joint prevention and control mechanism informed that the virus genome sequence of local cases in Zhejiang (including Ningbo) was highly homologous to the epidemic cases in Shanghai and Jiangsu, and it was the same associated epidemic. The case specimen of Ningbo CDC was sequenced for three generations, and the result was a Delta mutant (evolutionary branch of AY.4) Warsaw strain.
What are the symptoms of Delta virus infection?
There are some signs of Delta virus infection. If you have a headache, dry throat, fever, excessive phlegm and weakness, these symptoms may be the symptoms of δ virus infection, so detect them as soon as possible. So we can judge whether it is possible to be infected with Delta virus and whether we have been to high-risk areas according to these symptoms.
How toxic is Delta strain?
1, fast propagation speed:
Presenting cross-provincial communication, which is currently spread in at least 20 cities in China; Delta strain of COVID-19 variant virus has spread to about 100 countries, and it is the most easily spread COVID-19 variant found so far.
2. Highly contagious:
Guangzhou, Guangdong, a case of non-contact transmission of virus in 14 seconds; According to the data released by the British Ministry of Health, the number of confirmed cases of Delta reported in Britain in the last week has increased by 46% compared with the original number. At present, Delta mutant virus accounts for 99% of new cases in Britain.
Delta mutant * * * has 13 mutation, which may cause the change of S protein structure. Some research data show that these mutations will affect the spread of the virus and the ability to be neutralized by antibodies.
3, the incubation period is short:
Academician Zhong Nanshan said that the incubation period of Delta virus in the body is relatively short, and it will occur in two or three days, and some even occur in 24 hours. Some Delta 10 days have five generations.
4, the symptoms are not typical:
Patients infected with Delta strain may only have symptoms such as fatigue, dysosmia and mild muscle soreness in the early stage. This is not like the symptoms before COVID-19's mutation: fever, fatigue, dry cough, but also symptoms such as itchy throat, sore throat, stuffy nose, runny nose, diarrhea, abnormal taste and loss of sense of smell.
5. Long treatment time:
From the current observation results, the treatment cycle of COVID-19 mutant Delta virus strain is longer, and it is easier to develop into severe disease than the infected people before mutation.
6. Redefine the closed contact:
It used to be thought that the close contacts were two days before the onset of the disease, the patients' families were in the same office, or there were * * * people eating, meeting and so on within one meter. This is called close contact.
According to the characteristics of Delta virus, the definition of close contacts of Delta strain of COVID-19 mutant virus was modified. People who were in the same space, unit, building and four days before onset were close contacts.
What is the mode of transmission of Delta strain?
Respiratory droplets spread: respiratory droplets ejected from sneezing, coughing or even talking carry viruses, which can cause infection in people who are in close contact with him. This is the most important way.
Contact with pollutants spread: respiratory droplets and secretions pollute the surface of objects, and the virus can survive for a period of time. Others will get infected by touching the surface of contaminated objects with their hands. When they touch their mouths, eyes and noses, they will be infected.
Aerosol transmission: indoors, in a small space with poor ventilation, if the infected person coughs or sneezes, it will form very fine respiratory secretions particles, which can hover in the air and be inhaled by others, which can lead to infection. Even if the person who discharges the virus leaves this space, there will still be virus in the air for a certain period of time, which will cause infection after others enter.
How to protect yourself?
Adhere to the prevention and control measures of normalized epidemic situation: wear masks scientifically, wash hands frequently and ventilate frequently, and try not to go to places with dense crowds and poor air circulation. Consciously abide by epidemic prevention measures, and cooperate with public places to do prevention and control measures such as wearing masks, checking code and temperature, and walking rice noodles.
Reduce unnecessary parties: it is not appropriate to hold or participate in multi-person dinners, avoid gathering in confined spaces, keep the activity time as short as possible, and pay attention to opening windows and ventilation.
Actively vaccinate COVID-19 vaccine: Vaccination is the most effective measure to prevent diseases.
Important reminder:
At present, China is facing the double challenge of importing Delta and Omicron strains. The peak of Spring Festival travel rush is about to begin, the flow and gathering of people are increasing sharply, and the situation of epidemic prevention and control is grim. In areas where the epidemic has occurred, it is necessary to speed up screening, transfer and isolation, find and control risk personnel as soon as possible, and block the route of transmission as soon as possible; Promote the implementation of regional surveys to prevent the spread of the epidemic. We must do everything possible to ensure the people's material supply and basic medical needs, and ensure that the people's demands are promptly responded and resolved.