Evidence from Britain shows covid-19 vaccines are very effective


THE SECOND wave of the pandemic has been devastating in much of the world. Since September 1st covid-19 has claimed the lives of 1.6m people, compared with 850,000 in the preceding nine months. In America alone, the death toll passed 500,000 on February 22nd. What is more, new variants that may be more transmissible, more deadly or better at evading the body’s immune response are spreading.

At last, some optimism is budding. More than 200m doses of covid-19 vaccine have been administered across 92 countries. After a slow start, America’s programme is gathering speed: 16% of adults have received a first shot, and President Joe Biden is on target to meet his goal of 150m doses by his 100th day in office. The number of infections in the country is falling by half every 14 days.

In Israel, where vaccination has got off to the fastest start, evidence of falling deaths and hospitalisation rates appeared a couple of weeks ago. Britain is the first big country to show similar results. This has emboldened Boris Johnson, the prime minister, to announce a cautious and phased easing of restrictions in England on February 22nd. It will begin with the reopening of schools on March 8th (Northern Ireland, Scotland and Wales set their own timetables).

Two months have passed since Britain became the first country in the world to start a mass-vaccination programme on December 8th. In that time 31% of adults have received at least one dose of either the Pfizer-BioNTech or AstraZeneca-Oxford vaccines. By January 24th 80% of England’s 2.8m over-80s—those at the front of the national queue—had received their first dose. They were followed by the country’s 4.7m septuagenarians: by February 7th 83% of this group had been inoculated.

There is growing evidence that these vaccines work outside clinical trials. A study from Scotland released on February 22nd tracked the health of 1.1m people vaccinated between December 8th and February 15th. It found that the Pfizer-BioNTech vaccine reduced the hospitalisation rate among inoculated Scots by 85% four weeks after their first dose; the AstraZeneca-Oxford vaccine lowered hospitalisations by 94%. (The variation between the effectiveness of the vaccines may be down to age differences among the recipients rather than the vaccines themselves.)

Publicly available data from England show a similar trend. The daily death toll from covid-19 peaked on January 22nd at 1,164 (on a seven-day moving average). It has since fallen by 64%. The decline has been greatest among the old. Deaths have fallen by 66% among people aged 85 and over, by 62% among those between aged 65 to 84 and by 60% among the rest of the population (see chart). This does not appear to be a statistical fluke: a similar demographic dividend is observable in the decline in hospital admissions (though not in cases), and in regional data. These findings are bolstered by the Scotish study, too—the effect of lower hospitalisations among vaccinated groups should be observable in the aggregate data. The effect, although still small, will help Mr Johnson to stick to his timetable for easing: in England people aged 80 and over account for 6% of cases but 60% of deaths.

Britain’s experience, with the evidence from Israel, offers hope to other countries, not least because it suggests the vaccines are effective against the more transmissible (and possibly more deadly) variant of SARS-CoV-2, known as B.1.1.7, which has been dominant since Christmas. Although Mr Johnson has made many mistakes, the roll-out of vaccines has been a success. If all goes to plan England’s last restrictions will be removed on June 21st. Logistical problems and political infighting have led to slow roll-outs in many other countries, including members of the EU. The evidence from Britain shows that once jabs are in arms, the simple beauty of science alone will write the headlines.