Delta does not Escape Vaccines, Vaccines Stop Transmission, Patents and More

3 min readAug 8, 2021

Vaccines vs Delta

The Pfizer/BioNTech vaccine has been shown to be ~88% effective against symptomatic disease against Delta (B 1.617.2 aka India variant), whereas the Oxford/Astrazeneca vaccine showed ~60% efficacy. [1]

As with previous strains, this correlates well with neutralising antibody titres. [2]

**Figure 1.** Neutralising antibody titres for the Pf/BNT vaccine against variants. Souce: [2]

Antibodies generated from the J&J vaccine were also shown to only be slightly affected. [3]

In line with this, so far unpublished data allegedly shows that efficacy against Delta is ~71%. [4,5]

Delta appears to be outcompeting the more vaccine resistant Beta (B 1.351 aka South Africa variant) variant but not the Gamma (P.1 aka Brazil variant) variant. [6,7]

**Figure 2.** Variants in South Africa (top) and Brazil (bottom) over time. Source: nextstrain.org generated plots, see [6,7]

Several news outlets claimed that vaccines were only ~40% effective against Delta based on unpublished data from Israel. This dataset was too small at the time of analysis to properly assess efficacy. [8]

Lambda Variant

Lambda (C.37 or Peru variant) has been intermittently presented as a new threat by news outlets, despite being identified in August 2020 and not gaining global prominence.

The rise of Lambda in South America is clear and well documented. [9,10]

However, in the USA where both Delta and Lambda cases are seen, Delta seems to be gaining prominence much faster:

**Figure 3.** Variants and their prominence in the USA over time. Source: nextstrain.org data.

Duration of Immunity

A recent study examined patients who have recovered from COVID-19 and found that antibodies remain relatively unchanged between 6 and 12 months post-recovery. [11]

This same study shows that vaccination of these individuals increases the potency of their antibodies.

Vaccines Stop Spread & are Better than Infection

It is worth reiterating that there is direct evidence for vaccines halting infection (and thereby transmission) altogether and not only symptomatic infection. This was demonstrated in the SIREN study in the UK. Approximately 85% protection towards infection was seen for PF/BNT two doses (does not include variants). [12]

A recent case study from the CDC in Kentucky showed that unvaccinated patients who had previously recovered from COVID-19 are more than 2 times more likely to become infected with SARS-CoV-2. [13]

Patents

It is again worth re-iterating that patent protections are not a bottleneck in vaccine production. [14]

For example, Moderna announced in October 2020 they will not enforce COVID-19 related patents while the pandemic is ongoing. [15]

Third Dose

Both Moderna and Pfizer have researched the effects of a third dose of their existing vaccines. [16,17]

This could be valuable for immunocompromised patients, those on immunosuppressants and the elderly, who are less protected after vaccination.

Talks of a booster shot for all highlight the gigantic inequality in vaccine accessibility on a global scale.

The FDA and CDC have not entertained this possibility yet. [18]

References

Delta does not Escape Vaccines, Vaccines Stop Transmission, Patents and More

Written by Michael Bogdos