There’s been a lot of discussion recently about #SARSCoV2 #vaccine effectiveness, hospitalisation, and the reason for increasing case numbers, in spite of our high rates of vaccination. This thread will not provide a definitive explanation for the above 1/n However, I’m hopeful it will provide context to inform the discussion. TL:DR The vaccines are not 100% effective so our current level of uptake – measured across the entire population – will not be sufficient, in isolation, to suppress #SARSCoV2 transmission in the community 2/n

An updated thread on the Delta variant and the reasons for our concern. As any new variant emerges, there are three main issues that we consider: transmissibility; infection severity; and impact on pre-existing immunity (reinfection risk) & vaccine effectiveness 1/n Firstly, based on available evidence, the Delta variant appears to be between 40% and 60% more transmissible than the Alpha variant, which has been dominant in Ireland for the last 5 months 2/n

An introductory thread on B.1.617.2 and why we’re concerned about vaccine effectiveness (VE) against this virus. TL:DR The vaccines will work against B.1.617.2 but two doses of vaccine will be required to optimise effectiveness 1/n The primary way of measuring likely VE (or more specifically antibody effectiveness) against a virus in the lab is the neutralisation test. In this test, we try to grow (or culture) the virus in the presence of antibodies in the laboratory 2/n

A short thread on PCR #SARSCoV2 There’s been a lot of discussion recently about the use of PCR (Polymerase Chain Reaction) for the diagnosis of #SARSCoV2 infection, and the interpretation of its results. 1/n Hopefully, this thread can provide some background and context for those who are not familiar with the technique. PCR has become the cornerstone of molecular diagnostics in virology, and is, simply put, a technique for amplifying DNA (and indirectly RNA). 2/n

#Coronaviruses: an introductory thread/primer. #Coronaviruses are a family of viruses that cause respiratory & intestinal illness in birds, animals, and humans. #2019nCoV is the 7th coronavirus known to infect humans (#HCoV). Four #HCoVs – OC43, 229E, HKU1 & NL63 – cause mild ‘common cold-like’ illness. All of us have probably been infected with one or more of these at some time. These 4 #HCoVs only occasionally cause serious illness 2/n