The U.S. Food and Drug Administration (FDA) has approved use of vaccines for the coronavirus that causes COVID-19. Lisa Maragakis, M.D., M.P.H.感染预防高级主任，以及 Gabor Kelen, M.D., 约翰霍普金斯大学关键事件准备和响应办公室主任, 回答常见问题并解释疫苗如何影响当前的大流行.

Learn more about:

• COVID-19疫苗及其工作原理
• Getting the Vaccine
• Protection and Immunity
• 疫苗安全性和副作用
• Women and Children

COVID-19疫苗及其工作原理

How do vaccines work?

疫苗帮助人们对病毒或其他细菌产生免疫力. A vaccine introduces a less harmful part of that germ — or something created to look or behave like it — into a person’s body. The body’s immune system develops antibodies that fight that particular germ and keep the person from getting sick from it. Later, 如果这个人再次遇到这种细菌, 他们的免疫系统可以“识别”它，并“记住”如何对抗它.

冠状病毒有疫苗吗?

Yes, there are several 疾控中心推荐的COVID-19疫苗. 同样重要的是，接受一个 booster when you are eligible. 

疫苗如何预防COVID-19?

导致COVID-19的冠状病毒在每个病毒颗粒上都有蛋白质尖峰. 这些突刺帮助病毒附着在细胞上并引起疾病. Some of the coronavirus vaccines are designed to help the body “recognize” these spike proteins and fight the coronavirus that has them.

有效的疫苗有助于保护接种者免受严重疾病的侵害, hospitalization and death. Widespread vaccination will help limit spread through communities and will restrict the virus’s opportunity to continue to mutate into new variants.

我什么时候可以接种冠状病毒疫苗?

疫苗和增强剂正在美国各地分发.

如果您是约翰霍普金斯医学院的患者，请访问我们的 COVID-19疫苗信息和更新页面 有关接种疫苗或接受加强疫苗的最新信息. Your state’s health department website can also provide updates on vaccine distribution in your area.

Getting the Vaccine

The U.S. 美国食品和药物管理局(FDA)授权, 疾病控制和预防中心(CDC)现在建议, 为6个月及以上的每个人接种COVID-19疫苗, 还有5岁及以上的人的助推器. Individuals are up to date on vaccines and boosters after receiving all doses in the primary series and all boosters recommended, when eligible.

Vaccines: Individuals 6 months and older are fully vaccinated 2 weeks after the final dose in the primary series.

• 接种疫苗的建议根据你的年龄而不同, the vaccine you first received, and time since last dose. For details, please review the 疾病预防控制中心的COVID-19疫苗建议.
• COVID-19 vaccine recommendations for people who are moderately or severely immunocompromised include an additional dose in their primary series. For details, please review the 疾病预防控制中心的COVID-19疫苗建议 for those who are moderately or severely immunocompromised.

Boosters

1 booster: 疾病预防控制中心建议5岁及以上的人在符合条件的情况下接种强化疫苗. Please review the CDC’s booster guidelines for details. (时间安排会因不同而有所不同 immunocompromised.)

2 boosters: 美国疾病控制与预防中心建议为以下人群注射第二剂:

• Adults 50 and older
• 12岁及以上有中度或严重免疫功能低下者. Please review the CDC’s booster guidelines for details.   

Bivalent Booster

As of Oct. 12, 2023, the new COVID-19 booster recommendations for people ages 5 years and older is to receive 1 bivalent mRNA booster after completion of a monovalent primary series or previously received monovalent booster dose(s); these recommendations replace all prior booster recommendations for this age group.

• 推荐在6-17岁人群中使用二价Moderna加强剂
• Recommendations for use of a bivalent Pfizer-BioNTech booster dose in people ages 5–11 years

The CDC recommends a bivalent (containing components of both the original strain of the SARS-CoV-2 virus and the omicron variant of the virus) COVID-19 booster for people ages 5 years and older. The bivalent vaccines, which offer better protection against COVID-19 caused by the omicron variant than the earlier, monovalent vaccines, have been authorized for use as a single booster dose administered at least two months after primary or booster vaccination. The monovalent COVID-19 vaccines will no longer be available for booster doses in patients over the age of 5. However, the monovalent vaccines will remain available for the primary vaccine series in all patients and for booster doses in patients younger than 5 years old.

Visit the 疾病预防控制中心的COVID-19疫苗和加强页 for more details.

如果我已经感染了COVID-19，我应该接种COVID-19疫苗吗?

Yes, evidence continues to indicate that getting a COVID-19 vaccine is the best protection against getting COVID-19, 无论你是否已经感染了COVID-19.

• A 该研究发表于2021年8月 表示您之前是否感染过COVID-19且未接种疫苗, your risk of getting reinfected is more than two times higher than for those who were infected and got vaccinated.
• While evidence suggests there is some level of immunity for those who previously had COVID, 不知道你能被保护多久，不会再次感染COVID-19. Plus, the level of immunity provided by the vaccines after having COVID-19 is higher than the level of immunity for those who had COVID but were not subsequently vaccinated.
• Getting vaccinated provides greater protection to others since the vaccine helps reduce the spread of COVID-19.

At the time of vaccination, 一定要告诉你的护理人员你的COVID-19病史, 包括治疗方式, if any, 你收到了，当你恢复的时候. 等到隔离期结束后再预约接种疫苗.

Protection and Immunity

如果我接种了冠状病毒疫苗，我还需要戴口罩吗? Physical distance?

The CDC continues to monitor the spread of COVID-19 and makes recommendations for wearing face masks, both for those who are fully vaccinated 以及那些没有完全接种疫苗的人.

The CDC also recommends that masks and physical distancing are required when going to the doctor’s office, 医院或长期护理机构, 包括所有约翰·霍普金斯医院, care centers and offices.

约翰霍普金斯医学院目前的口罩安全指南没有改变, 我们仍然要求所有人员在我们所有设施内佩戴口罩.

Does taking over-the-counter medications before receiving the vaccine lessen its effectiveness?

Some studies have suggested that taking medications such as Tylenol or Advil before getting a vaccination might reduce your body’s ability to mount an immune response to the vaccine. 目前尚不清楚这些发现是否具有临床意义, though, and other studies did not find any effect of anti-inflammatory medications on the immune reaction to vaccines.

If you regularly take aspirin or other over-the-counter medications such as acetaminophen (e.g., Tylenol), ibuprofen (e.g.(如:布洛芬、安非他明)或萘普生(如:萘普生).g., Aleve)的其他医疗条件, 请按照医生的指示或根据需要继续这样做. Otherwise, it’s probably best to not take over-the-counter medications such as acetaminophen or ibuprofen that reduce fever or inflammation before receiving a vaccine. 如果您在接种疫苗后感到不适或有症状, 这是服用非处方药物来帮助你感觉更好的时候了.

疫苗安全性和副作用

我们如何知道COVID-19疫苗是否安全有效?

In order to be declared safe and effective, a COVID-19 vaccine must pass certain tests and standards. 像美国国家科学院这样的组织, 国立卫生研究院, and the Food and Drug Administration (FDA) use scientific data from research to help decide if and when new drugs and vaccines can become available to the public. 重要的是要注意，你不能通过疫苗感染COVID-19. The vaccines contain proteins or other biological substances to stimulate the immune response, but not the coronavirus itself.

Learn more about the COVID-19疫苗的安全性.

冠状病毒疫苗有哪些副作用?

你打过针的手臂可能会痛, 你可能会发烧，身体疼痛, 头疼和疲劳一两天. 寒战、淋巴结肿大也可能发生.

Read more about possible COVID-19 vaccine side effects. 

如果我有过敏症，可以接种COVID-19疫苗吗?

While there have been reports of severe allergic-type reactions in a very small number of patients, 疾病预防控制中心表示，对某些食物过敏的人, drugs, insects, 乳胶和其他常见的过敏原仍然可以获得COVID-19疫苗.

如果你对注射疫苗或其他疫苗有严重的过敏反应(过敏反应), 一定要和你的医生讨论COVID-19疫苗接种, 谁能评估你和你的风险. The vaccine provider should observe you for 30 minutes rather than the routine 15 minutes after vaccination, 如果你对第一针有过敏反应, you may not receive the second.

The CDC says that at this time, 任何对任何疫苗成分有严重过敏(如过敏反应)的人 should not get that vaccine.

Women and Children

儿童能接种COVID-19疫苗吗?

The U.S. 美国食品和药物管理局(FDA)授权 and the Centers for Disease Control and Prevention (CDC) now recommends 为6个月及以上的每个人接种COVID-19疫苗, 还有5岁及以上的人的助推器. Johns Hopkins Medicine encourages all families to have eligible children vaccinated with the COVID-19 vaccine.

Read more about 关于COVID-19疫苗，父母需要知道什么.