Italy says mRNA COVID jab efficacy stable after 7 months, but not for all

MILAN, October 6 (Reuters) – Seven months after the second dose, there is no reduction in the effectiveness of COVID-19 mRNA vaccines in the general population in Italy, while a slight decline is observed for some specific groups, according to the National Institute of Health (ISS) said Wednesday.

The report led by the ISS and the Department of Health looked at data up to Aug. 29 from more than 29 million people who had received two doses of an mRNA vaccine such as those produced by Pfizer and Moderna.

He indicated that in the general population, the efficacy against infection after seven months remained at 89%, while against hospitalization and death, this time six months after the second dose, it remained respectively at 96. % and 99%.

The results on protection against infection differ from a study carried out by Pfizer (PFE.N) and published on October 4 in the medical journal Lancet.

This showed that the effectiveness of the Pfizer / BioNTech vaccine in preventing infection fell to 47% from 88% six months after the second dose. Read more

The ISS study did not refer to the Lancet study, which focused on electronic health records of 3.4 million members from a U.S. health care provider, but did not include data on compliance with mask and occupancy guidelines, which could have affected testing frequency and exposure.

In Italy, people are forced to wear masks indoors and they were mandatory outdoors before summer, and strict rules of behavior were put in place, which may have influenced the results.

The ISS report said immunocompromised people saw their protection against infection drop starting 28 days after the second dose, with the reduction varying widely depending on the diseases that cause the weakened immune system.

In people with co-morbidities who are not necessarily immunocompromised, the study reported a reduction in protection against infection from 75% 28 days after the second dose to 52% after about seven months.

Efficiency among people over 80 and residents of nursing homes also declined slightly but remained above 80%, the ISS said.

Comparing the period when the Alpha variant was prevalent with that when the Delta variant was prevalent, the efficacy against infection increased from 84.8% to 67.1%, while the protection against hospitalization decreased much less, from 91.7% to 88.7%.

The Institute’s reports are among the documents that the Italian government takes into account in its health decisions. Rome must reflect in the coming weeks on the advisability of extending a third dose of vaccine to the entire population.

To date, the third dose, which began on September 20, has only been given to immunocompromised patients, those over 80, residents and operators of nursing homes, and health workers over 60. years or with co-morbidities or other factors leading to increased exposure to possible infection. .

The EMA, the European Union’s medicines regulator, said on October 4 that people with weakened immune systems should receive a third dose of a COVID-19 vaccine from Pfizer-BioNTech or Moderna, but left it to member states to decide whether the population at large should have a booster. Read more

Reporting by Emilio Parodi, editing by Gavin Jones and Alison Williams

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