• The World Health Organization (WHO) has identified the Delta variant as more transmissible and categorized it as a variant of concern
• While single dose vaccination was not sufficiently protective, the two-dose dosing scheme of the inactivated vaccines was effective against the Delta variant

By Kelum Bandara

A research team led by leading Chinese Epidemiologist Zhong Nanshan has identified that the administration of the full course of Chinese vaccines is effective against the Delta variant of Covid-19, the Chinese Embassy in Colombo said.    The World Health Organization (WHO) has identified the Delta variant as more transmissible and categorized it as a variant of concern. It has now become the dominant variant in the world leading to more cases of hospitalizations and deaths.   

According to a study done in China after the outbreak in South China’s Guangzhou, it has been found that the two shots of Chinese inactivated vaccines are 59.0 percent effective in the prevention of symptoms, 70.2 percent in preventing moderate symptoms and 100 percent in preventing severe symptoms.   

The results of the study have been published in the journal ‘Emerging Microbes & Infections on August 14, 2021. The Chinese Embassy in Colombo shared the findings with Daily Mirror.   

“After adjusting for age and sex, the overall VE (vaccine efficacy) for two-dose vaccination was 59.0% (95% confidence interval: 16.0% to 81.6%) against coronavirus disease 2019 (COVID-19) and 70.2% (95% confidence interval: 29.6% to 89.3%) against moderate COVID-19 and 100% against severe COVID-19 which might be overestimated due to the small sample size.   

The VE of two-dose vaccination against COVID-19 reached 72.5% among participants aged 40-59 years, and was higher in females than in males against COVID-19 and moderate diseases.   

While single dose vaccination was not sufficiently protective, the two-dose dosing scheme of the inactivated vaccine was effective against the Delta variant infection in real-world settings, with the estimated efficacy exceeding the World Health Organization minimal threshold of 50%,” the journal says.