What’s new this week?

• The more dangerous and transmissible Delta variant is forcing public health officials around the world to rethink Covid-19 measures, even for the vaccinated. 
• The strain was first identified in India in February, but several countries have this week imposed new restrictions in attempts to stop the variant from causing fresh outbreaks globally. 
• South Africa entered at least two weeks of lockdown on Sunday, with the government announcing some of the strictest measures since the early months of the pandemic. 
• In Australia, a cluster of infections of the variant in Sydney led the city of 5 million people into a two-week lockdown. 
• This is frustrating for locals. Australia was celebrated for its initial response to the pandemic. But with that security came complacency, particularly in the federal government, which failed to secure enough vaccine doses to prevent the regular “circuit breaker” lockdowns that come every time a handful of cases emerge. The country’s borders have also been all but shut for more than a year. 
• Meanwhile, a rapidly worsening situation across Russia is forcing the government to take extra steps to boost the country’s low vaccine rates. Authorities have tried to cajole people to get the shot by offering sweeteners, such as free cars and circus tickets. But they are also turning to more restrictive measures and employees in Moscow face losing their jobs if they don’t get vaccinated when asked to. 
• But while Russia, Australia and South Africa are struggling with low vaccination rates, the Delta variant is causing concerns even in countries that have inoculated a high proportion of their populations.
• It has become dominant in the United Kingdom, where it caused cases to spike last month, forcing authorities to postpone plans to lift restrictions. 
• Britain was hoping to out-vaccinate the Delta variant, opening its rollout to anyone over the age of 18 and pushing forward second doses. But despite having fully vaccinated nearly two-thirds of British adults, the UK is heading towards a potential third wave of Covid-19 and several countries have imposed strict rules on British travelers. 
• In the US, public health experts are also sounding alarms. The Delta variant has spread to nearly every state, feeding concerns over potential Covid-19 spikes in the fall. 
• The variant is expected to become the dominant coronavirus strain in the US, according to the CDC and its rapid spread is forcing some authorities to rethink protective measures. In Los Angeles County, officials have reinstated mask guidance for public indoor spaces — regardless of vaccination status. 
• The good news is that most of the existing Covid-19 shots seem to be effective against the new variant. 
• A study by Public Health England found this month that the Pfizer-BioNTech and Oxford-AstraZeneca vaccines are each highly effective — at 96% and 92% respectively — against hospitalizations from the Delta variant after two doses. Moderna’s vaccine was found in lab experiments to work against new variants such as the Delta strain, the company said. And Dr. Anthony Fauci, America’s top infectious diseases expert, said it’s highly likely the Johnson & Johnson vaccine also protects people against the Delta strain. 
• But to add to the concern, a new and slightly changed version of the Delta variant is now spreading in several countries. B.1.617.2.1 or AY.1 — Delta Plus for short — has an extra mutation that affects the spike protein, the part of the virus that attaches to the cells it infects. Because most of the coronavirus vaccines are designed to train the body to recognize the spike protein, or parts of it, there are worries the mutation could affect vaccine efficacy. 
• However, scientists say it’s too early to be certain. Other variants with the same mutation were not found to evade vaccines. For now, experts are largely cautioning the public and governments to remain watchful but calm.