Antibodies from Sinovac's Covid-19 shot fade after about 6 months, booster helps - study
Skip to main content
  • Home
  • Economy
  • Stocks
  • Analysis
  • World+Biz
  • Sports
  • Features
  • Epaper
  • More
    • Subscribe
    • COVID-19
    • Bangladesh
    • Splash
    • Videos
    • Games
    • Long Read
    • Infograph
    • Interviews
    • Offbeat
    • Thoughts
    • Podcast
    • Quiz
    • Tech
    • Archive
    • Trial By Trivia
    • Magazine
    • Supplement
  • বাংলা
The Business Standard

Saturday
July 02, 2022

Sign In
Subscribe
  • Home
  • Economy
  • Stocks
  • Analysis
  • World+Biz
  • Sports
  • Features
  • Epaper
  • More
    • Subscribe
    • COVID-19
    • Bangladesh
    • Splash
    • Videos
    • Games
    • Long Read
    • Infograph
    • Interviews
    • Offbeat
    • Thoughts
    • Podcast
    • Quiz
    • Tech
    • Archive
    • Trial By Trivia
    • Magazine
    • Supplement
  • বাংলা
SATURDAY, JULY 02, 2022
Antibodies from Sinovac's Covid-19 shot fade after about 6 months, booster helps - study

Coronavirus chronicle

Reuters
26 July, 2021, 08:30 pm
Last modified: 12 August, 2021, 12:25 pm

Related News

  • China's Sinovac Covid-19 booster weaker against Omicron - Hong Kong study
  • AstraZeneca to set up division for vaccines and antibody therapies
  • 99% people with second dose vaccine have antibodies: Study
  • Brazil health regulator suspends use of 12 million Sinovac vaccine shots
  • North Korea turns down Sinovac Covid-19 vaccine doses

Antibodies from Sinovac's Covid-19 shot fade after about 6 months, booster helps - study

Chinese researchers reported the findings from a study of blood samples from healthy adults aged between 18-59 in a paper published on Sunday, which has not been peer reviewed

Reuters
26 July, 2021, 08:30 pm
Last modified: 12 August, 2021, 12:25 pm
FILE PHOTO: A worker performs a quality check in the packaging facility of Chinese vaccine maker Sinovac Biotech, developing an experimental coronavirus disease (COVID-19) vaccine, during a government-organized media tour in Beijing, China, September 24, 2020. REUTERS/Thomas Peter/File Photo
FILE PHOTO: A worker performs a quality check in the packaging facility of Chinese vaccine maker Sinovac Biotech, developing an experimental coronavirus disease (COVID-19) vaccine, during a government-organized media tour in Beijing, China, September 24, 2020. REUTERS/Thomas Peter/File Photo

Antibodies triggered by Sinovac Biotech's Covid-19 vaccine declined below a key threshold from around six months after a second dose for most recipients, but a third shot had a strong booster effect, a lab study showed.

Chinese researchers reported the findings from a study of blood samples from healthy adults aged between 18-59 in a paper published on Sunday, which has not been peer reviewed. 

Among participants who received two doses, two or four weeks apart, only 16.9% and 35.2% respectively still had neutralising antibodies above a threshold set by researchers, below which the antibody level is considered low or undetectable, six months after the second shot, the paper said.

Those readings were based on data from two cohorts involving more than 50 participants each, while the study gave third doses of the vaccine or placebo to a total of 540 participants.

Researchers said it was unclear how the decrease in antibodies would affect the shot's effectiveness, since scientists have yet to figure out precisely the threshold of antibody levels for a vaccine to be able to prevent the disease.

Apart from durable antibodies, other components in humans immune systems such as T cells and B cell memory elicited by the vaccine may also contribute to protection, researchers involved in the study said, although the study did not provide data on those factors.

"In the short-to-medium term, ensuring more people complete the current two-dose schedule of CoronaVac (Sinovac's vaccine) should be the priority," the paper said.

Participants in some cohorts who received a third dose of the Sinovac shot about six months after the second showed around a 3-5 fold increase in antibody levels after a further 28 days, compared with the levels seen four weeks after the second shot.

As of end-June, Sinovac has delivered more than 1 billion doses of the vaccine, a major vaccination tool in China, Brazil, Indonesia and Chile.

Other Covid-19 vaccine makers are seeking to get authorisation for booster shots. Pfizer and partner BioNTech said earlier this month they had planned to ask US and European regulators within weeks to authorise a booster dose of its Covid-19 vaccine, based on evidence of greater risk of infection six months after inoculation and the spread of the highly contagious Delta variant.

Siti Nadia Tarmizi, a senior health ministry official in Indonesia, told Reuters on Tuesday that clinical data from the country showed the reduced antibody level is still enough to provide protection, without providing details.

She said the immunisation advisory board recommends a booster vaccination 12 months after the second dose.

Indonesia has started giving booster shots produced by Moderna to medical workers this month, including those who had received Sinovac doses.

Philippines' Health Secretary Francisco Duque said on Tuesday there is no recommendation yet from the country's vaccine expert panel on giving a booster shot but experts are discussing the possibility.

Turkey has already started offering a third dose from either Sinovac or Pfizer to some people who have got Sinovac shots.

The research paper on Sinovac's vaccine said that the study did not test the antibodies' effect against more transmissible variants, and that further research was needed to assess antibody duration after a third shot.

The study was conducted by researchers at disease control authorities in Jiangsu province, Sinovac, and other Chinese institutions.

Top News

Sinovac Covid-19 Vaccine / antibody

Comments

While most comments will be posted if they are on-topic and not abusive, moderation decisions are subjective. Published comments are readers’ own views and The Business Standard does not endorse any of the readers’ comments.

Top Stories

  • In rain, heat, filth – they fight against cancer
    In rain, heat, filth – they fight against cancer
  • Evaly: Justice stuck within a server password
    Evaly: Justice stuck within a server password
  • Fewer cattle, buyers mark 1st day of Eid cattle sales in Chattogram
    Fewer cattle, buyers mark 1st day of Eid cattle sales in Chattogram

MOST VIEWED

  • Former North Korean defectors living in South Korea, release balloons containing one dollar banknotes, radios, CDs and leaflets denouncing the North Korean regime, towards the north near the demilitarized zone which separates the two Koreas in Paju, north of Seoul January 15, 2014. REUTERS/Kim Hong-Ji/File Photo
    North Korea blames 'alien things' near border with South for Covid outbreak
  • People wearing protective face masks commute amid concerns over the new coronavirus disease (COVID-19) in Pyongyang, North Korea March 30, 2020, in this photo released by Kyodo. Picture taken March 30, 2020. Mandatory credit Kyodo/via REUTERS
    S Korea says leaflets sent by defectors unlikely to be cause of Covid in N Korea
  • Test tubes are seen in front of displayed Pfizer and Biontech logos in this illustration taken, May 21, 2021. Reuters: llustration
    BioNTech, Pfizer to start testing universal vaccine for coronaviruses
  • A woman holds a small bottle labelled with a "Coronavirus COVID-19 Vaccine" sticker and a medical syringe in this illustration taken October 30, 2020. REUTERS/Dado Ruvic/File Photo
    S Korea approves first domestically developed Covid vaccine
  • Photo: Collected
    US medical experts call for Omicron-specific Covid boosters
  • David E Adler. Sketch: TBS
    Who managed Covid-19 best, and why?

Related News

  • China's Sinovac Covid-19 booster weaker against Omicron - Hong Kong study
  • AstraZeneca to set up division for vaccines and antibody therapies
  • 99% people with second dose vaccine have antibodies: Study
  • Brazil health regulator suspends use of 12 million Sinovac vaccine shots
  • North Korea turns down Sinovac Covid-19 vaccine doses

Features

Photo: Collected

Sapiens – A Graphic History 

14h | Book Review
Black-naped Monarch male  Photo: Enam Ul Haque

Black-naped Monarch: A sovereign who never abandoned the Indian subcontinent

15h | Panorama
The 136-year-old company on its last legs

The 136-year-old company on its last legs

16h | Features
Agricultural worker walks between rows of vegetables at a farm in Eikenhof, south of Johannesburg, South Africa. Photo: Reuters

With vast arable lands, why is Africa dependent on imported grain?

13h | Panorama

More Videos from TBS

Dhaka University celebrating 102nd founding anniversary today

Dhaka University celebrating 102nd founding anniversary today

13h | Videos
Ctg Int'l Trade Fair returns after a 2-year hiatus without Covid restrictions

Ctg Int'l Trade Fair returns after a 2-year hiatus without Covid restrictions

14h | Videos
Bangladeshis among top 6 nationalities seeking asylum in Europe

Bangladeshis among top 6 nationalities seeking asylum in Europe

15h | Videos
RUET organises Robotronics 2.0

RUET organises Robotronics 2.0

15h | Videos

Most Read

1
Padma Bridge from satellite. Photo: Screengrab
Bangladesh

Padma Bridge from satellite 

2
Meet the man behind 'Azke amar mon balo nei'
Splash

Meet the man behind 'Azke amar mon balo nei'

3
Photo: TBS
Bangladesh

Motorcycles banned on Padma Bridge 

4
Photo: Collected
Economy

Tech startup ShopUp bags $65m in Series B4 funding

5
World Bank to give Bangladesh $18b IDA loans in next five years
Economy

World Bank to give Bangladesh $18b IDA loans in next five years

6
Investor Hiru fined Tk2cr for market manipulation
Stocks

Investor Hiru fined Tk2cr for market manipulation

EMAIL US
contact@tbsnews.net
FOLLOW US
WHATSAPP
+880 1847416158
The Business Standard
  • About Us
  • Contact us
  • Sitemap
  • Privacy Policy
  • Comment Policy
Copyright © 2022
The Business Standard All rights reserved
Technical Partner: RSI Lab
BENEATH THE SURFACE
Workers with minimum safety equipment are busy producing iron rods at a local re-rolling mill at Postogola in Old Dhaka. Reused metals from the adjacent shipyards in Keraniganj have played a major role in establishing several such mills in the area. PHOTO: Mumit M

Contact Us

The Business Standard

Main Office -4/A, Eskaton Garden, Dhaka- 1000

Phone: +8801847 416158 - 59

Send Opinion articles to - oped.tbs@gmail.com

For advertisement- sales@tbsnews.net