Israel: Pfizer vaccine allows infection but preventing severe illness Vaccine showed just 39 percent effectiveness for preventing delta variant infections Thailand to join COVAX, acknowledging low vaccine supplyThe head of Thailand’s National Vaccine Institute has apologized for the country’s slow and inadequate rollout of coronavirus vaccines, promising it will join the U.N.-backed COVAX program to receive supplies from its pool of donated vaccines next yea Longer periods between first and second Pfizer vaccinations could boost antibodies: studyA new study suggests that waiting nearly eight weeks can encourage strong antibody development. New Lambda Covid variant may be jab-resistant and more infectious, experts warnA study carried out by the University fo Chile found the Lambda Covid variant may be resistant to the CoronaVac jab, while other scientists discovered it may be twice as infectious as the original virus Two doses of Pfizer or AstraZeneca shots effective against delta variant, study findsThe study reiterated that one shot of the vaccines is not enough for high protection from the highly transmissible variant. Two Pfizer, AstraZeneca doses work against Delta variant: studyTwo doses of Pfizer shot 88 percent effective against Delta variant, while AstraZeneca doses have 67 percent efficacy. Study: Pfizer vaccine 88 percent effective against delta variantTwo doses of the Pfizer COVID-19 vaccine are 88 percent effective against the delta variant, according to a new study. Sinopharm's COVID-19 shot induces weaker antibody responses to Delta -studySinopharm's COVID-19 vaccine elicited weaker antibody responses against the Delta variant, based on the first published study of its effect against the more contagious version.