Why are Covid cases so high when vaccination is rampant?

LONDON – Looking at the data on Covid cases in the United States, the United Kingdom and the rest of Europe, you would be forgiven for thinking that, despite 18 months of global health crisis and advanced vaccination deployments, we are in just as bad a situation as we always have been.

Certainly, the number of daily Covid cases recorded in the West remains high, and even resembles earlier peaks at different points, or Covid waves, during the pandemic.

The current 7-day moving average of daily new cases is 153,246, an increase of 4.9% from the previous 7-day moving average (of 146,087). The current 7-day moving average is 123.6% higher than the value seen about a year ago, according to data compiled by the Centers for Disease Control and Prevention (CDC). In total, more than 40 million cases of Covid have been counted in the United States since the start of the pandemic.

UK case rates also remain high. As of September 6, the seven-day average of daily new cases was nearly 39,000 and the number of daily cases remained high throughout the week; nearly 40,000 new cases were reported on Wednesday and about 38,000 cases were recorded on Thursday, according to government data.

In the EU + EEA area (a total of 30 countries), in the seven days leading up to September 5, 405,774 new cases were recorded, according to the European Center for Disease Prevention and Control, along with Ireland, the France, Sweden, Portugal, Greece and Bulgaria among the countries reporting the highest number of new cases per 100,000 inhabitants.

The high number of cases remains attributable to the spread of the highly infectious delta variant, which usurped previous variants which were themselves more infectious than the original strain of Covid-19.

Nonetheless, the increase in cases has accompanied the advancement of vaccination programs in the West, with the majority of adults in the United States and Europe now fully vaccinated.

In the United States, 62.4% of all people over 12 are fully immunized, according to CDC data, while more than 82% of those over 65 are fully protected. In the UK, 80.4% of the population over 16 is fully vaccinated and in the EU / EEA 70.4% of adults have received two doses of a coronavirus vaccine, according to data from the ECDC.

Importantly, the number of hospitalizations and deaths accompanying the high number of cases remained lower (and for some countries, much lower) than in the early stages of the pandemic, when vaccination rates were much lower, proving that coronavirus vaccines used in the West dramatically reduce the risk of serious infection, hospitalization and death. Hospitalizations in the United States remain high, according to data from Our World in Data.

Yet none of the vaccines used in the United States or Europe are 100% effective, which means that some vaccinated people will contract Covid (called “breakthrough cases”) and a small number will fall ill. . The predominant delta variant also reduced the effectiveness of the proposed vaccines and some new studies show that the immunity provided by the injections wanes over time.

CNBC asked UK-based epidemiologists why cases remain so high given relatively high vaccination rates in the West.

“The delta variant is very contagious and that explains the still high number of cases now that we mix much more freely since most restrictions were relaxed,” Andrew Freedman, Cardiff infectious disease reader, told CNBC on Thursday. University School of Medicine. .

“Those who catch Covid now are a mix of unvaccinated, partially vaccinated and doubly vaccinated people. A large portion of the new infections are in children and adolescents (unvaccinated),” he noted.

“We know that vaccines are only partially effective in preventing people from catching the delta variant, but are much more effective in protecting against serious illness, hospitalization, and death. Fully vaccinated people usually only have signs of illness. mild symptoms if they do get it, although a small minority, especially older and more frail people, continue to contract more serious illness. “

In the UK, the latest data from the ZOE Covid study, which tracks symptoms and infections of Covid in the community using data from around one million people each week, estimates that in the fully vaccinated population, it There are currently 17,674 new symptomatic cases daily in Britain

He noted, in his latest research published Thursday, that “cases in this group have been increasing steadily but have now leveled off with last week’s figure at 17,342.”

Meanwhile, new Covid cases are highest among 0-18 year olds and 18-35 year olds, many of whom are only partially vaccinated (two doses of a Covid vaccine are vital to achieve maximum protection), or not vaccinated.

Similar data is for the United States and the rest of Europe over the past month: CDC data shows that the greatest number of cases have been counted among adolescents aged 16 to 17 (although the groups ages 12 to 49 have all experienced a sharp increase in cases). In the EU / EEA, the highest number of cases is in the 25-49 age group, closely followed by 15-24 year olds and an increasing number of cases in children, aged 5. at 14.

Epidemiologists and public health experts have long expressed the opinion that Covid-19 is just something we will have to get used to, that the virus will become endemic and can no longer be eradicated.

The pursuit of a so-called ‘zero Covid’ strategy (aimed at eliminating all cases of Covid) has been seen as a desperate cause by most countries, although Australia and New Zealand have pursued such a strategy. Australia, however, announced in late August that it was abandoning such a policy, given the spread of the highly contagious delta variant. New Zealand is sticking to its strategy, for now.

Danny Altmann, professor of immunology at Imperial College London, told CNBC that companies need to assess how well they will tolerate the virus.

“We have always said, and still maintain, that vaccines are amazing and give huge levels of protective neutralizing antibodies,” he told CNBC on Thursday. Although clinical studies show that the delta variant reduces the effectiveness of vaccines, Altmann noted “there is so much margin of protection that” most “people should be safe.”

“In a sense, that’s how we’ve seen it play out – with the delta variant and without the vaccination we would now be at several thousand deaths a day, but we’re only down to ‘only’ a few. hundreds, so there is a tangible mitigation of critical illness, ”he said.

“However, our protection seems less robust against delta than we expected when you consider that in the UK there are around 40,000 cases per day, including many of these breakthroughs … [and] people become seriously ill but are not hospitalized, ”he said, noting that Israel’s data on booster injections showed that additional injections could re-boost antibody levels and combat breakthrough cases.

Much of the debate around Covid right now, Altmann said, “goes back to this political / philosophical debate about what we are now trying to achieve.”

“The extremes of the argument are either that, at least until we see what happens in the fall / winter, we hit our target because a relatively high vaccine rollout has meant hospitals can pretty much to cope… Or, the other point of view is that we will never have normalcy unless we strive to adopt a zero Covid strategy, which should include vaccination in our schools to stop the spread there ” , he noted.

Those calling for a zero Covid strategy included people who thought “we are ducks sitting in perpetuity for ever more cases, until we let a much more resilient variant go through to really make us fail,” said Altmann.