Have we reached herd immunity?

When the Office for National Statistics released the last antibody survey a fortnight ago, the results were underwhelming. After watching prevalence in the population shoot upwards for months, the figure had plateaued at 55 per cent. There were several reasons suggested for the stall, including the move to giving second doses and difficulties detecting fading antibodies (which the ONS is quick to point out does not necessarily mean a person no longer has immunity). But, regardless, it raised concerns that it might take longer to reach high antibody prevalence rates than previously hoped. Thankfully, today’s update has provided plenty of cheer. In the two weeks following the last update (taking

Why do old people have fewer antibodies after the vaccine?

The UK policy of delaying second doses of the Pfizer vaccine has been criticised by some as risky, with Pfizer warning that there is no data on the effectiveness of its vaccine other than for the dosing regime used in phase 3 trials: two doses, 21 days apart. But evidence is steadily trickling through. Earlier in the week I wrote here about the Scottish population-wide study which found that a single dose of the Pfizer vaccine reduced hospital admissions by 85 per cent between 28 and 34 days after the jab. This morning comes Imperial College’s React-2 study, which paints a picture that is, on the face of it, rather less

Is this the key to understanding Covid immunity?

Just how strong an immunity do Covid patients develop after they have acquired the infection and how long does it last? The question is vital to the likely future passage of the pandemic, and to how well vaccines will protect us in the long term. Several studies have suggested there is a sharp decline in antibodies to SARS-CoV-2 over time – a paper from Imperial College’s React study in October, for example, revealed that the proportion of the population showing antibodies to the virus declined from 6 per cent in June to 4.4 per cent in September. The researchers were at pains to emphasise that the presence of antibodies does

Israel’s antibody breakthrough

The Israeli government is reporting this morning that the country’s Institute for Biological Research has made a breakthrough in the development of a potential treatment against SARS-CoV-2, the virus which causes Covid-19. Scientists there have isolated a ‘monoclonal neutralising antibody’ which could potentially neutralise the virus after infection. The antibody was obtained from the blood of an infected patient. It is called monoclonal because it is generated from a single cell – which could allow vast quantities of the antibody to be produced quickly. Is it the breakthrough that could make all the difference? Treatment of novel viruses with monoclonal neutralising antibodies has been under development for some time, notably