People wait to take PCR samples in Guangzhou city, Guangdong province, China on May 26, 2021 – Photo: GETTY IMAGES
On September 15, the Global Times Reportedly, a group of leading Chinese epidemiologists, including scientist Zhong Nanshan, has mapped the complete transmission chain of the Delta variant for the first time in the world.
This study was published in the journal ClinicalMedicine belong prestigious international medical journal The Lancet. The study is expected to provide reliable data for Delta variant prevention and control measures.
Chinese epidemiologists conducted a study based on the outbreak caused by the Delta variant in Guangzhou city, Guangdong province, southern China. This outbreak started on May 21, 2021 and was brought under control in June.
The team combined viral genetic sequencing and epidemiology technologies to precisely map the complete transmission sequence of the Delta variant. They also incorporate clinical sources.
The researchers found that during the Guangzhou outbreak, the epidemic was mainly transmitted through direct and close contact, with 30.8% of cases of infection through shared meals, followed by family contact. (30.13%), community transmission (18.59%) and other transmission routes including work and social contact (19.87%).
According to the above study, the Delta variant has a shorter incubation period and a faster transmission rate, with an average incubation period of only 4.7 days, significantly shorter than the parent strain (6.3 days). ).
Chinese experts divide infections into generations. Variant Delta can spread across four generations of infections in 10 days, with the fastest intergenerational transmission taking less than 24 hours. The viral load in people with the Delta variant was significantly higher than in the parent strain.
The above study shows that the rapid tracing, isolation and timely detection of infected people, timely management and control in key locations, and PCR testing of all people in some areas in the country. Special circumstances play an important role in preventing the spread of Delta variants.
This outbreak has been successfully controlled within 7 generations of infections.