Add BNT/Pfizer press release about third shot

README.md

@@ -346,6 +346,7 @@ Note that the WHO will generally be unable to make statements that their more pr
 * [Pfizer and BioNTech Submit Request to Expand Conditional Marketing Authorization of COMIRNATY® in the EU to Adolescents](https://investors.biontech.de/news-releases/news-release-details/pfizer-and-biontech-submit-request-expand-conditional-marketing) as well as filing for emergency use authorization with the FDA in the US, after a phase 3 trial on children between 12 and 15 years of age, with around 2000 participants who generally tolerated the vaccine well, resulting in a vaccine efficacy of 100%; [Canada approves the vaccine for use in ages 12-15](https://covid-vaccine.canada.ca/info/regulatory-decision-summary-detailTwo.html?linkID=RDS00802) on 5 May 2021
 * [Evidence for increased breakthrough rates of SARS-CoV-2 variants of concern in BNT162b2 mRNA vaccinated individuals](https://www.medrxiv.org/content/10.1101/2021.04.06.21254882v2) looks at variants of COVID acquired by individuals vaccinated with Pfizer/BioNTech in Israel, and finds an odds ratio of 8:1 for being infected with B.1.351 (South African variant) compared to unvaccinated individuals, and of 26:10 for B.1.1.7 (UK variant)
 * [Effectiveness of the BNT162b2 Covid-19 Vaccine against the B.1.1.7 and B.1.351 Variants](https://www.nejm.org/doi/full/10.1056/NEJMc2104974) shows that in Qatar, where vaccination with Pfizer/BioNTech is at an advanced state, most cases of COVID since March 2021 have been either B.1.1.7 (UK variant) or B.1.351 (South African variant), and the effectiveness against B.1.1.7 is 89.5%, while against B.1.351 it is 75%, with overall effectiveness against severe or fatal disease being 97.4%
+* [Pfizer and BioNTech Provide Update on Booster Program in Light of the Delta-Variant](https://investors.biontech.de/news-releases/news-release-details/pfizer-and-biontech-provide-update-booster-program-light-delta), stating that a third shot of the original vaccine (BNT162b2) makes neutralization titers against the original virus and the Beta variant 5 to 10 times higher than after two shots, and they anticipate efficacy against Delta as well, but at the same time they are developing a modified vaccine that targets the full spike protein of the Delta variant, and an initial trial for it should begin in August 2021
 
 #### Vaxzevria by Oxford-AstraZeneca (AZD 1222 or ChAdOx1)