#16,095
Late yesterday the Washington Post got hold of an unpublished internal CDC document (which, in all fairness, was dated yesterday) describing the increased transmissibility (equating it to chickenpox), and increased severity, of the Delta variant (see ‘The war has changed’: Internal CDC document urges new messaging, warns delta infections likely more severe), which has touched off a firestorm of media coverage.
Those who have been following the studies coming out of the UK, Denmark, Israel, and elsewhere (see short list below) probably aren't terribly surprised by these revelations, but the stark messaging in this document is sobering.
A few (of many) foreshadowing studies include:
Preprint: Impact of SARS-CoV-2 Variant on the Severity of Maternal Infection and Perinatal Outcomes
UK: Updated Risk Assessments On COVID Delta & Beta Variants
ECDC Threat Assessment On Spread of COVID Variant B.1.617.2 (Delta) VOC
Eurosurveillance: Increased Transmissibility & Global Spread of SARS-CoV-2 VOCs as of June 2021
CDC Elevates Delta (B.1.617.2) Variant to VOC & Lancet Report On Hospitalizations & Vaccine Effectiveness
Despite these warnings, many people around the world - weary after 18 months of lockdowns and NPI requirements - have increasingly eschewed pandemic restrictions, believing - or at least hoping - that the worst is behind us.
This belief has made it increasingly difficult to convince people to get vaccinated, wear face masks, and to avoid crowds.
In my last blog (Nature Scientific Rpts: Rates of SARS-CoV-2 Transmission & Vaccination Impact the Fate of Vaccine-resistant Strains) we looked at modeling suggesting how this could turn out badly, potentially with the creation of new, vaccine resistant variants.
After a frantic nearly 16-hour news cycle, the Washington Post has published this now-infamous internal document (https://www.washingtonpost.com/context/cdc-breakthrough-infections/94390e3a-5e45-44a5-ac40-2744e4e25f2e/?_=1). You'll want to view it in its entirety, but I've posted a handful of screenshots below.
Aside from the scientific evidence presented (some of which is preliminary), the `tone' of this document, and the `how do we explain this to the public now?' narrative, are the most striking (see slide #2 below).
With the anti-vaccine brigade using every opportunity on social media to demonize the COVID shot, this is a legitimate concern. The amount of anti-vaccine propaganda echoed every day across social media seems to increase with each passing day.
The advice, however, to trivialize breakthrough cases, by calling them `rare' or a `small percentage', is almost sure to backfire as breakthrough cases increase.
As the next graphic illustrates that, while not a panacea for the pandemic virus, the current vaccines still provide substantial protection against the Delta variant. That said, as many as 35,000 symptomatic breakthrough infections occur every week.
The next slide compares the transmission rate of Delta against earlier variants, and other infectious diseases, putting Delta well ahead of seasonal influenza, pandemic flu, and even smallpox.
Between vaccine breakthrough infections, a substantial number of unvaccinated individuals, remarkably increased transmissibility, and increased severity - without taking other measures - the Delta variant threatens to sweep the nation, derail the economic recovery, overburden healthcare systems, and will undoubtedly lead to even greater loss of life.
While it would have been far better had the CDC released this document before the media got hold of it (admittedly difficult, given how quickly it was leaked), it is important that the public understand what the next few months may bring.
Most epidemiologists I follow believed (and warned) that the recent roll back of NPIs, and the canceling of pandemic precautions was premature, and would lead to a resurgence of COVID.
Regrettably, many of the decisions to `reopen' society were based based more on politics, (legitimate) economic concerns - and perhaps a bit of unfounded hope - than on science.
Walking them back now will be difficult, and judging by the resistance I'm seeing, may be impossible. Add in vaccine hesitancy - and the militant opposition to mandatory vaccines - and the next few months are likely to be both contentious, and costly.
Individuals who elect to get the vaccine, wear face masks in public, and avoid `risky' environments will almost certainly fare better than those who don't, but we will all be at increased risk during this next wave.
The biggest danger is that Delta will eventually give way to an even more dangerous variant; perhaps one that evades our current vaccines completely. While I hope that doesn't happen, so far, we've not had very many lucky breaks with this virus.
As the CDC says, the war has changed.
Hopefully we can adjust to those changes, and act accordingly.
Stay tuned.
