Article Category: Vaccine Q&A
Vaccine recalls or withdrawals due to safety issues are rare. Recalls are usually initiated voluntarily by a vaccine manufacturer before any adverse events are reported. For example, ongoing monitoring of vaccine production may show that an irregularity has caused a batch of vaccines to lose their strength. In this case, people who have received a vaccine from that batch may need to be vaccinated again to ensure they are protected.
The COVID-19 mRNA vaccine technology has been rigorously assessed for safety, and clinical trials have shown that mRNA vaccines produce an immune response that has high efficacy against disease. mRNA vaccine technology has been studied for several decades, including in the contexts of Zika, rabies, and influenza vaccines. mRNA vaccines are not live virus vaccines and do not interfere with human DNA.
Medical professionals can best advise individuals on whether or not you should receive a COVID-19 vaccine. There are very few conditions that would exclude someone from being vaccinated. Based on available evidence, people with a history of severe allergic reactions to any ingredients of the COVID-19 vaccine should generally be excluded from COVID-19 vaccination in order to avoid possible adverse effects.
If you are currently sick or experiencing symptoms of COVID-19, you can get vaccinated once your primary symptoms have resolved.
In addition to the general recommendations above, each vaccine may have specific considerations for specific populations and health conditions.
Vaccine safety monitoring is ensured at the national, regional, and global level. As is standard practice in all national immunization programmes, WHO supports the set up of safety monitoring systems for COVID-19 vaccines in every country. After a COVID-19 vaccine is introduced in a country, WHO works with vaccine manufacturers, health officials and other partners to monitor for any safety concerns on an ongoing basis. Specific safety concerns that may arise are evaluated by WHO and an independent group of experts (the Global Advisory Committee on Vaccine Safety, or GACVS) in conjunction with the relevant national authorities.
Suspected safety events officially reported to WHO go through a series of rapid verification steps involving an independent panel of experts. WHO shares the results of these evaluations on its website.
WHO also coordinates with local, regional, and national health officials to investigate vaccine safety concerns and advise on next steps. Information is also made available through the Vaccine Safety Net, a publicly available network of digital international resources on vaccine safety that have been approved by WHO.
Scientists around the world are developing many potential vaccines for COVID-19. These vaccines are all designed to teach the body’s immune system to safely recognize and block the virus that causes COVID-19.
Several different types of potential vaccines for COVID-19 are in development, including:
- Inactivated or weakened virus vaccines, which use a form of the virus that has been inactivated or weakened so it doesn’t cause disease, but still generates an immune response.
- Protein-based vaccines, which use harmless fragments of proteins or protein shells that mimic the COVID-19 virus to safely generate an immune response.
- Viral vector vaccines, which use a safe virus that cannot cause disease but serves as a platform to produce coronavirus proteins to generate an immune response.
- RNA and DNA vaccines, a cutting-edge approach that uses genetically engineered RNA or DNA to generate a protein that itself safely prompts an immune response.
For more information about all COVID-19 vaccines in development, see this WHO publication, which is being updated regularly.
WHO recommends that those most at risk of severe illness, death and exposure to COVID-19 get vaccinated first.
These include frontline health workers (especially those providing COVID-19 patient care), older people and those living with other diseases, or existing conditions including hypertension, diabetes, cardiovascular disease, HIV or cancer.
COVID-19 vaccines save lives. When you get the call, get the vaccine.
Expired vaccines should not be used. They should be disposed of in accordance with national guidelines.
Yes. If you are a young adult you are not at the highest risk of severe illness or dying, but you are still at risk.
Some vaccines are not yet recommended for those younger than 18 years old since they have not yet been tested in this age group. Once vaccines are approved and recommended for use in this age group, you should follow the national recommendations.
Yes. Senegal, South Africa, Egypt, Tunisia and Morocco are the only African countries with some vaccine manufacturing capacity.
For more African countries to develop these capabilities, we need more international cooperation and greater sharing of expertise.
With flexibility around technology transfer and the waiving of intellectual property rights during the pandemic, investment in African countries could start by focusing on filling and packaging COVID-19 vaccines. From this, further investment could help build up more complex capacities for manufacturing and research and development.
More detailed information on vaccine manufacturing capacity in Africa can be found here.