Sumary of Is Delta defeating us? Here’s why the variant makes contact tracing so much harder:
- The Greater Sydney lockdown began on June 26 and almost a month later, New South Wales is recording around 100 new COVID cases a day.
- We are also seeing the virus spread well beyond the initial eastern suburbs cluster.
- The virus then spread from NSW to Victoria resulting in a lockdown there too, followed by South Australia.
- It has mutations which make it more contagious than Alpha, and more able to evade the immunity conferred by vaccines.
- It’s more infectious, probably causes more severe disease, and challenges our vaccines One study found the amount of virus shed from people infected with Delta to be over 1,000 times greater than from the original 2020 strain identified in Wuhan.
- So, the successful test and trace strategy of NSW, which controlled the Crossroads Hotel outbreak a year ago without needing a stringent lockdown, has not worked as well against Delta.
- Delta makes the job so much harder In the absence of enough vaccines for everyone, control of the epidemic requires: identifying all new cases by testing and isolating them to prevent further transmission tracing all contacts and quarantining them for the incubation period, so they don’t cause further transmission.
- SARS-CoV-2 is highly infectious in asymptomatic or pre-symptomatic people, so without contact tracing these people would carry on, unaware they are infected, and may infect many others.