The study on the effectiveness of the Inactivated SARS-COV-2 (CoronaVac) Vaccine from Sinovac. The CoronaVac was the first to be distributed in Indonesia and has the biggest volume of doses used to date since rolled out in January.
As of June 20, 2021, Indonesia has given almost full doses to almost 12 percent of the population. The nation's total caseload that time was almost two million (as per this article, the number has increased to 2.2 million cases). The number of deaths recorded was 54,662 cases.
Of the confirmed cases, 65,667 patients over the age of 18 had to be treated in ICUs. Thirty percent of the patients are between 50 and 59 years old, and 42 percent over 60 (data per April 30, 2021).
The Balitbangkes study used a sample of 86,916 elderly people in Jakarta. They are over 60 years old and have no history of PCR (+) Covid-19 before vaccination and before the observation period began in early March.
The study followed a progression in which 40,245 elderly were fully vaccinated between March 4 and 29. The observations continued for 28 days post-vaccination (follow-up period: March-May 2021) and the data was compared side by side with unvaccinated elderly from the same group.The study has also stated that from the beginning there were limitations, which was the lack of comorbid baseline data.
The results of the study found that full inoculations (two doses) were able to prevent 86 percent of symptomatic cases starting from day 14 after the second dose among 40,245 senior citizens. The effectiveness in preventing hospitalizations and case deaths per the same period was even greater, at 92 and 95 percent, respectively.
The study also contradicted its previous observation that the Sinovac Vaccine was only 35 percent effective in preventing Covid symptoms after 14 days from the first dose. Its ability to prevent hospitalizations and deaths was not even significant compared to those who had not been vaccinated at all during the period.
Another result is that the same vaccine is 92 percent effective in preventing symptomatic cases on day 7 after the second dose of injection. The effectiveness was recorded to decrease thereafter to 74 percent on day 21 and 52 percent on day 28.
Source: https://en.tempo.co/read/1479849/study-claims-sinovac-vaccine-protects-jakarta-elderlie