Booster vaccines for Covid-19


booster vaccine (image from unsplash)

89.1% of the UK population has now received a first dose and 81% who have received both doses of Covid-19 vaccines.


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Why do you need a booster vaccine?

Due to the short time spans however, it is still unclear how long protection from the Covid-19 vaccines lasts, but there is some evidence, particularly in the case of the Pfizer vaccine, that it declines over time, and starts to decline within six months from the second dose.


Insufficient time has passed to know what levels of protection might be expected 6 to 12 months after the primary course. Taking a precautionary position, the Joint Committee on Vaccination and Immunisation (JCVI) considers that it is preferable to maintain a high level of protection in vulnerable adults throughout winter.


Booster vaccines are therefore recommended to help to ensure longer lasting protection. It will help those at higher risk from coronavirus, who were prioritised at the start of the vaccine programme, and ensure that they have enough protection during winter months. This is particularly important as It is likely that coronavirus (COVID-19) infections will continue to circulate in the coming months, alongside seasonal influenza and other respiratory viruses.


Additionally, as the virus spreads and mutates, it may start to resist existing vaccines.

Therefore, a booster programme may offer extra protection against such variants. So far, evidence indicates that COVID-19 vaccines provide higher levels of protection against hospitalisation or dying from the virus.


Booster vaccine groups

So in order to continue this high level of protection through the coming winter, the JCVI advises that booster vaccines are offered to those more at risk from serious disease, and who were vaccinated during Phase 1 of the vaccine programme (priority groups 1 to 9). This includes:

  • those living in residential care homes for older adults

  • all adults aged 50 years or over

  • frontline health and social care workers

  • all those aged 16 to 49 years with underlying health conditions that put them at higher

  • risk of severe COVID-19, and adult carers

  • adult household contacts of immunosuppressed individuals

The JCVI advises that the booster vaccine dose is offered no earlier than 6 months after

completion of the primary vaccine course, in the same order as during Phase 1.

People vaccinated early during Phase 1 will have received their second dose approximately 6 months ago. Therefore, it would be appropriate for the booster vaccine programme to begin in September 2021, as soon as operationally practical.


Which vaccine is being used for the boosters?

The Pfizer or Moderna vaccines will be the most likely booster vaccines offered, as evidence shows that this type of vaccine will work well as a booster.


The Pfizer, Moderna and Oxford/AstraZeneca vaccines have all been approved for use as booster jabs by the UK medicines regulator, the MHRA. The Oxford/AstraZeneca vaccine has only been approved as a booster for use in people who had it as their first and second vaccine.


Younger people

As most younger adults will only have received their second COVID-19 vaccine dose by late summer or early autumn, the benefits of booster vaccination in this group will be considered at a later time.


加強劑疫苗

英國現時大概已有差不多九成的人口接種了第一劑抗新冠病毒的疫苗,也有多於八成的人口接種了兩劑的疫苗。


我為何需要加強劑?

由於疫苗研發時間較短,因此未能確實它的效力能維持多久,但有一些證據顯示,疫苗的效力在接種了第二劑後的六個月後可能會有所減退,尤其是輝瑞疫苗。


由於冬天將至,而又因未有足夠時間去瞭解疫苗在六至十二個月後的效力,為了保障脆弱成人的健康及讓他們在冬天仍然持有高效的抗疫能力,接種疫苗聯合委員會決定為這些人士接種第三劑疫苗。這可增強他們在冬天抵抗新冠病毒、感冒菌及其他呼吸性病菌。


現時病毒繼續在社區傳播及變種,因此,加強劑能增強抵抗變種病毒的能力。數據顯示,到目前為止,疫苗能提供高度保障,減低因感染病毒而需住院或死亡的情況。


接種加強劑的優先組別

聯合委員會建議沿用最初接種疫苗的優先組別來決定可優先接種加強劑的人士。這包括:

  • 老人院的住客

  • 所有50歲以上的人士

  • 前線醫護人員及社區照顧員

  • 所有16至49歲、具有潛在健康狀況及感染病毒的高危人士及其成年人照顧者。

  • 與有免疫抑制人士同住的成年人

聯合委員會建議以上人士要在接種了第二劑的六個月後才可接種加強劑。早期接受疫苗注射的人士應已可符合六個月的條件,因此,接種加強劑計劃安排在今年九月開展。


加強劑會選用那種疫苗?

雖則輝瑞 (Pfizer)、莫德納 (Moderna)及牛津 (Oxford/AstraZeneca) 疫苗都獲英國藥物監管局 (MHRA) 通過可作加強劑之用,但一般加強劑都會選用輝瑞或莫德納疫苗,因為證據顯示這兩種疫苗作為加強劑較為有效。若第一劑和第二劑均是接種牛津疫苗的人士才可選用牛津疫苗為加強劑。


年青人士

由於大多數年青人是在夏天後期及初秋時才接種第二劑疫苗,因此,政府會稍後才考慮為他們接種加強劑。


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加强剂疫苗

英国现时大概已有差不多九成的人口已接种了第一剂抗新冠病毒的疫苗,也有多于八成的人口接种了两剂的疫苗。


我为何需要加强剂?

由于疫苗研发展时间较短,因此未能确实它的效力能维持多久,但有一些证据显示,疫苗的效力在接种了第二剂后的六个月后可能会有所减退,尤其是辉瑞疫苗。


由于冬天将至,而又因未有足够时间去了解疫苗在六至十二个月后的效力,为了保障脆弱成人的健康及让他们在冬天仍然持有高效的抗疫能力,接种疫苗联合委员会决定为这些人士接种第三剂疫苗。 这可增强他们在冬天抵抗新冠病毒、感冒菌及其他呼吸性病菌。


现时,病毒继续在社区传播及变种,因此,加强剂能增强抵抗变种病毒的能力。 数据显示,到目前为止,疫苗能提供高度保障,减低因感染病毒而需住院或死亡的情况。


接种加强剂的优先组别

联合委员会建议沿用最初接种疫苗的优先组别来决定可优先接种加强剂的人士。 这包括:

  • 老人院的住客

  • 所有50岁以上的人士

  • 前线医护人员及社区照顾员

  • 所有16至49岁、具有潜在健康状况及感染病毒的高危人士及其成年人照顾者

  • 与有免疫抑制人士同住的成年人


联合委员会建议以上人士要在接种了第二剂的六个月后才可接种加强剂。 早期接受疫苗

注射的人士应已可符合六个月的条件,因此,接种加强剂计划安排在今年九月开展。


加强剂会选用那种疫苗?

虽则辉瑞(Pfizer)、莫德纳(Moderna)及牛津(Oxford/AstraZeneca)疫苗都获英国药物监管局(MHRA)通过可作加强剂之用,但一般加强剂都会选用辉瑞或莫德纳疫苗,因为证据显示这两种疫苗作为加强剂较为有效。 若第一剂和第二剂均是接种牛津疫苗的人士才可选用牛津疫苗为加强剂。


年青人士

由于大多数年青人是在夏天后期及初秋时才接种第二剂疫苗,因此,政府会稍后才考虑为他们接种加强剂。

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