As the world faces the third year of the Covid-19 pandemic, the latest data by Johns Hopkins University revealed that global Covid-19 cases had surpassed 400 million, with more than 5,761,208 deaths worldwide.
The global caseload reached the grim milestone of 100 million on January 26, 2021, rose to 200 million on August 4, 2021, and exceeded 300 million on January 6, 2022.
If one talks about Covid-19, one can’t escape mentioning the importance of vaccination and now booster shots for many of us. Presently, the New Zealand government has been urging all eligible New Zealanders to get themselves a booster shot to combat the ongoing threat of Omicron. It is believed that being fully vaccinated with two shots provides great protection against Delta, but boosters are the best way to fight Omicron.
According to the Ministry of health, as of February 9, 2022, 1,666,710 booster doses have been administered across NZ.
Earlier, the government stressed the importance of being fully vaccinated and is now focussing on getting more and more people to the booster vaccine. Many people have many questions about whether we will need to take boosters as and when a new variant of Covid-19 spreads –or will it be safe to take booster shots, and how frequently it should be taken.
Indian Weekender spoke to experts for answers....
‘We may need an annual Covid-19 vaccination'
Michael Baker
Epidemiologist and Professor, Department of Public Health, University of Otago.
On the need for boosters: Boosters add an important additional layer of protection for those already vaccinated. They reduce the chance that vaccinated people will get infected with the Omicron variant and get seriously ill from it. They also reduce transmission of the virus so will slow the pandemic and protect the healthcare system.
On requiring boosters as and when a new variant emerges: We will need to plan for the emergence of new variants. It may not be necessary to roll out new boosters for each new variant as current vaccines and boosters are likely to provide at least partial protection against them. Ultimately, we may need an annual Covid-19 vaccination as we do for influenza, where this vaccine is reformulated regularly to keep ahead of virus evolution.
On how frequently booster shots should be taken: Covid-19 boosters currently use the same vaccines as the primary vaccinations (i.e. vaccine doses one and two). Therefore, they have been through the same rigorous safety checks as all Covid-19 vaccines. We are still learning about the optimal timing of vaccine doses and boosters to produce the best possible protection from Covid-19 infection. The interval from the second dose to booster dose has been reduced from the original six months to three months in New Zealand to ensure as many people as possible can receive a booster before the Omicron wave of infection peaks here. All people eligible for a booster dose should get one as soon as they are eligible.
‘The frequency of booster will depend on how much of a problem the virus is.’
Helen Petousis-Harris
Vaccinologist and Associate Professor, Dept of General Practice and Primary Health Care, University of Auckland.
On the need for boosters: Boosters help prevent people from getting infected. While there is still such a big challenge with Covid-19, they will help slow down the number of sick people and the spread. Once the pandemic has ended, most people will have resistance to the virus and boosters or new formulations might be more critical for people at high risk of complications rather than everyone.
On requiring booster as and when a new variant emerges: Ongoing boosters or new versions targeting variants of concern will depend upon the effectiveness of existing immunity to prevent severe disease”.
On how frequently booster shots should be taken: The boosters have a very good safety profile. The frequency will depend on how much of a problem the virus is.
‘As the virus continues to evolve, vaccines will be updated periodically to provide immunity against the latest variants’
Michael Plank
Covid-19 Modeller and Professor, School of Mathematics and Statistics, University of Canterbury.
On the need for boosters: At the moment, all adults in New Zealand are strongly recommended to take a booster dose three months after their second dose. This is especially important for the Omicron variant, as the third dose boosts your immunity higher than after two doses and reduces your risk of needing hospital treatment.
On requiring booster as and when a new variant emerges: The booster dose is exactly the same as the first two doses and is very safe. More than a billion people worldwide have had the booster, and serious side effects are extremely rare. At the moment, there are no plans for a fourth dose, with the possible exception of high-risk groups like immuno-compromised people.
On how frequently booster shots should be taken: It’s uncertain what vaccines be needed in the long term. It’s possible that, as the virus continues to evolve, vaccines will be updated periodically to provide immunity against the latest variants. This is very similar to what happens with the annual flu jab.
‘Further boosters may be needed, and they will likely be for certain high-risk groups particularly.'
Joan Ingram
Medical Advisor, Immunisation Advisory Centre and infectious disease specialist.
On the need for boosters: Booster doses are essential because our antibody levels wane or reduce for most adults over time. Protection against any infection, especially infection with minimal or no symptoms, wanes relatively quickly (within a few months), but protection against severe disease lasts longer. Booster doses can assist in building protection back up.
Booster doses are significant for highly vulnerable people such as the frail elderly or those with significant health problems. The other group for whom boosters are particularly needed is people with continued occupational exposure to SARS-CoV-2 and/or caring for people with Covid-19 disease, such as health care and border workers. They are more likely to be exposed to SARS-CoV-2 infection and have a higher potential to transmit the infection to people at risk of severe disease.
On requiring booster as and when a new variant emerges: We can't know how the virus will evolve in the future or what other vaccines may be developed. Still, I can say that we review the safety data and real-world effectiveness of further boosters before decisions are made to use them. If they are needed, their safety and efficiency will be checked in the same way they are for all vaccines, including influenza.
On how frequently booster shots should be taken: Further boosters may be needed, and they will likely be for certain high-risk groups. ?