Vaccine Safety Research and Safety Studies
The United States’ long-standing vaccine safety system ensures vaccines are as safe as possible. As science advances and new information becomes available, this system will continue to improve.
Vaccine safety research:
- Ensures the benefits of vaccines approved in the U.S. outweigh the risks.
- Defines which groups should not receive certain vaccines.
- Describes side effects and adverse events reported after vaccination.
- Evaluates whether reported side effects and adverse events can be directly linked to a vaccine.
Vaccine Safety Publications
Access vaccine safety research conducted by CDC’s Immunization Safety Office (ISO) .
The Health and Medicine Division of the National Academies Reports on Vaccine Safety
Read summaries of vaccine safety reports by the Institute of Medicine.
Archive: The Immunization Safety Office Scientific Agenda
Learn about the development of ISO’s scientific and research agenda.
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Is the COVID-19 Vaccine Safe?
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Featured Experts:
Lisa Maragakis, M.D., M.P.H.
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Yes. The two mRNA vaccines, Pfizer and Moderna, authorized by the U.S. Food and Drug Administration (FDA) and recommended by the Centers for Disease Control and Prevention (CDC), are very safe and very good at preventing serious or fatal cases of COVID-19. The risk of serious side effects associated with these vaccines is very small.
Lisa Maragakis, M.D., M.P.H. , senior director of infection prevention, and Gabor Kelen, M.D. , director of the Johns Hopkins Office of Critical Event Preparedness and Response, answer questions about the safety of the COVID-19 vaccines.
COVID-19 Vaccine Safety — What We Know
- The Pfizer and Moderna vaccines are strongly recommended as safe and effective at preventing serious illness or death from COVID-19.
- From December 2020 to December 2021, about 470 million doses of COVID-19 vaccine have been given in the U.S.
- Roughly 12 months of data, including data from tens of thousands of participants in clinical trials, show that the vaccines are safe and effective at preventing serious disease or death due to COVID-19.
- Additional shots and boosters are also authorized for those who meet the guidelines.
- mRNA technology used in the Pfizer and Moderna vaccines has been in development for over 15 years.
- The Pfizer and Moderna vaccines received full FDA approval , which means more data show how well that particular vaccine works.
- Due to potential blood clots following administration of the Johnson & Johnson vaccine, the CDC updated its recommendations in December 2021. The CDC noted that the two mRNA vaccines, from Pfizer and Moderna, are preferred over the Johnson & Johnson vaccine.
Are there risks or safety concerns regarding the COVID vaccines?
To help catch risks or safety concerns, the CDC and FDA monitor possible safety issues with the COVID-19 vaccines. This ongoing work has led to revised recommendations for the Johnson & Johnson vaccine and information about rare side effects tied to the Pfizer and Moderna vaccines.
- Johnson & Johnson/Janssen. In December 2021, the CDC updated its recommendations and stated that either of the two mRNA vaccines is preferred over the Johnson & Johnson (J&J) COVID-19 vaccine. The CDC explained that the Pfizer and Moderna vaccines are preferred due to a greater risk for developing rare but severe blood clots, called thrombosis with thrombocytopenia syndrome (TTS), following administration of the J&J vaccine. The CDC noted that there are some situations when a J&J vaccine may still be used , if the recipient understands the risks and benefits of the J&J vaccine. Read about side effects related to the rare blood clot .
At Johns Hopkins Medicine, we offer Pfizer and Moderna vaccines throughout our vaccine clinics.
- Pfizer and Moderna. After observing rare occurrences of myocarditis following the second injection of the Pfizer and Moderna COVID-19 vaccines, the CDC released information for the public . Most of these myocarditis events happened in teens and young adults, and the majority of the cases were mild and cleared up on their own. Read about side effects related to myocarditis .
This review process continues to monitor vaccine safety. Potential risks of COVID-19 vaccines are reviewed and weighed against the benefits of protection that the vaccines offer as well as the known, serious risk of harm due to COVID-19.
What if I got a J&J vaccine? Should I worry about blood clots?
If you received a Johnson & Johnson vaccine more than three weeks ago, you do not need to watch for side effects related to blood clots.
If you received the J&J vaccine within the last three weeks, you should watch for possible symptoms of TTS and get medical help immediately if you have any of the following:
- Severe or persistent headaches or blurred vision
- Shortness of breath
- Leg swelling
- Persistent abdominal pain
- Easy bruising or tiny blood spots under the skin near the injection site
Is there a risk of an allergic reaction to a COVID vaccine?
According to the CDC, anyone who has a severe allergy (e.g., anaphylaxis) to any of the mRNA vaccine ingredients should not receive this vaccine . The CDC says people with allergies to certain foods, insects, latex and other common allergens can safely receive the COVID-19 vaccine. Those with a history of severe allergic reaction (anaphylaxis) to injectables or other vaccines should discuss the vaccination with their doctor, who can evaluate and assess their risk.
The COVID-19 Vaccines: What you need to know | Las vacunas anticovid-19: información imprescindible
How was the COVID-19 vaccine developed so quickly?
The relatively quick development of these vaccines does not mean safety measures were skipped. There are several reasons why the COVID-19 vaccines were developed faster than other vaccines:
- The technologies used to develop the COVID-19 vaccines have been in development for years to prepare for outbreaks of infectious viruses. The manufacturing processes were ready very early in the COVID-19 pandemic.
- Countries shared genetic information when it was available about SARS-CoV-2, the coronavirus that causes COVID-19, which gave vaccine developers an early start at finding a vaccine.
- The testing processes for the vaccines didn’t skip any steps, but the vaccine developers conducted some stages of the process simultaneously to gather as much data as quickly as possible.
- Governments gave money to vaccine developers in advance, so the companies had resources they needed.
- Some types of COVID-19 vaccines were created using messenger RNA (mRNA), a new technology that allows a faster approach than the traditional way vaccines are made.
- Social media enabled companies to reach out to and enroll study volunteers, and plenty of people wanted to help, so there were enough research participants to test the COVID-19 vaccines.
- Because SARS-CoV-2 is so contagious and widespread, many volunteers who got the vaccines were exposed to the virus, and with so many exposures, it took a shorter time to see if the vaccines worked.
- Companies began manufacturing vaccines ahead of their authorization or approval so some supplies would be ready if authorization occurred.
What steps are taken to help make sure the COVID-19 vaccines are safe?
Safety is always a top priority as federal agencies work with vaccine manufacturers and independent scientific organizations to develop, study, authorize and approve new vaccines. Here are some of the steps taken for COVID-19 vaccines, as well as other vaccines:
- Careful testing. All vaccines go through clinical trials to test safety and effectiveness. For the COVID-19 vaccine, the FDA set high safety standards for vaccine developers to meet. This graphic from the National Institutes of Health shows the four phases a vaccine goes through before it is released to the public.
- Authorization for emergency use. If a vaccine or medicine is needed to address an emergency situation such as the COVID-19 pandemic, once it is shown to be safe and effective, the FDA can grant it an emergency use authorization (EUA). An EUA allows a vaccine, treatment or medication to be used before the formal FDA approval.
- Continuous monitoring for problems and side effects. Once a vaccine gets an EUA and is being given to people, the FDA and the CDC continue to watch carefully in case problems arise. Data on the vaccine’s safety record accumulates over time, as more and more people who receive it report on their experience and any side effects. One important way to report adverse events after vaccination is through the Vaccine Adverse Event Reporting System .
Learn more from the CDC about the safety steps for the COVID-19 vaccine .
Demographics of the COVID-19 Vaccine Trials
Do I still have to wear a mask if I get a vaccine?
The CDC continues to monitor the spread of COVID-19 and makes recommendations for wearing face masks, both for those who are fully vaccinated as well as people who are not fully vaccinated.
The CDC also recommends that masks and physical distancing be required when going to a doctor’s office, hospital or long-term care facility, including all Johns Hopkins hospitals, care centers and offices.
Johns Hopkins Medicine’s mask safety guidelines have not changed, and we still require everyone to wear masks inside all of our facilities.
Can I get COVID-19 from the vaccine?
You cannot and will not get COVID-19 from any of the vaccines. The COVID-19 vaccines do not have any virus or other infectious material in them.
What about the safety of COVID-19 vaccination for diverse groups of people?
The FDA and other reviewers closely consider diverse populations and include them in the trials. The clinical trials for the first two COVID-19 vaccines included members of underrepresented minorities and older age groups, and people with conditions such as obesity, diabetes, and heart and respiratory conditions.
Does Johns Hopkins Medicine recommend that I get a COVID-19 vaccine?
Yes, we recommend that everyone who is eligible get vaccinated with one of the currently authorized mRNA COVID-19 vaccines: Pfizer or Moderna. We view both as highly effective in preventing serious disease, hospitalization and death from COVID-19 (including disease caused by the very contagious delta and omicron variants of the coronavirus), and we believe that their benefits outweigh their risks.
COVID Omicron Variant: What You Need to Know
Booster Shots and Third Doses for COVID-19 Vaccines
COVID Natural Immunity: What You Need to Know
Related Topics
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- NEWS EXPLAINER
- 16 February 2021
COVID vaccines and safety: what the research says
- Ariana Remmel
You can also search for this author in PubMed Google Scholar
As people around the world receive COVID-19 vaccines, reports of temporary side effects such as headaches and fevers are rolling in. Much of this was expected — clinical-trial data for the vaccines authorized so far suggested as much. But now that millions of people are vaccinated, compared with the thousands enrolled in early studies, reports of some rare, allergic reactions are surfacing, and questions are arising about whether any deaths are linked to the shots.
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Nature 590 , 538-540 (2021)
doi: https://doi.org/10.1038/d41586-021-00290-x
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Logunov, D. Y. et al. Lancet https://doi.org/10.1016/S0140-6736(21)00234-8 (2021).
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News & Research
Covid-19 vaccine safety, study affirms overall safety of covid vaccine, dangers of infection.
Image: Chaz Bharj. iStock/Getty Images Plus
Over the past year, results from a series of clinical trials have demonstrated the efficacy and safety of COVID-19 vaccines in preventing serious illness, hospitalizations, and deaths.
Yet, with sporadic reports of rare adverse events, one question has remained unanswered: Just how safe are COVID-19 vaccines in the real world, outside of clinical trials?
Get more HMS news here
Now, a study published Aug. 25 in The New England Journal of Medicine by researchers from Clalit Research Institute in Israel, Harvard Medical School, and the Harvard T.H. Chan School of Public Health answers that question.
The research, which assessed the safety of the Pfizer/BioNTech BNT162b2 mRNA vaccine, is based on analysis of data from nearly 2 million individuals in Israel and represents one of the largest real-world assessments of COVID-19 vaccine safety to date.
The findings, the researchers said, affirm the overall safety of the vaccine and underscore that the risk of adverse consequences from actual infection with SARS-CoV-2 far outweighs potential vaccine risks.
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The study involved two analyses: A comparison of adverse events between vaccinated and unvaccinated individuals, and between unvaccinated people infected with SARS-CoV-2 and unvaccinated noninfected people.
The study showed that few adverse events were associated with the vaccine. Myocarditis, or inflammation of the heart muscle, the most serious of them, was rare, with a rate of 2.7 excess cases per 100,000 vaccinated people. This means that for every 100,000 individuals, 2.7 more cases of myocarditis occurred than would be expected, the researchers said.
By contrast, the risk of myocarditis was notably higher among infected but unvaccinated individuals, occurring at a rate of 11 excess cases per 100,000 people.
Coronavirus infection—but not vaccination—was also associated with greatly increased risk of pericarditis (an inflammation of the area around the heart), heart arrhythmias, heart attacks, strokes, pulmonary embolism, deep-vein thrombosis, acute kidney damage, among others.
Vaccine hesitancy
“ To date, one of the main drivers of vaccine hesitancy has been a lack of information regarding potential side effects of the vaccine,” said study co-author Ben Reis, HMS assistant professor of pediatrics at Boston Children’s Hospital and director of the predictive medicine group in the Computational Health Informatics Program at Boston Children’s .
“This careful epidemiological study provides reliable information on vaccine safety, which we hope will be helpful to those who have not yet decided about vaccination, ” Reis said.
“ Those who have hesitated until now to get vaccinated due to concerns about very rare side effects, such as myocarditis, should be aware that the risks for this very same side effect are actually higher among unvaccinated infected individuals,” Reis said.
The results are based on records from Clalit Health Services in Israel, one of the world’s largest integrated health record databases. The analysis is the largest peer-reviewed evaluation of the safety of a COVID-19 vaccine in a nationwide mass-vaccination setting.
“The extensive nationwide rollout of Israel’s COVID-19 vaccination campaign provided the Clalit Research Institute with a unique opportunity to assess, through its rich and comprehensive digital datasets, the safety of the vaccine in a real-world setting, without needing to rely on individual-driven active reporting of side effects” said study senior author Ran Balicer, director of the Clalit Research Institute and Chief Innovation Officer for Clalit.
“These results show convincingly that this mRNA vaccine is very safe and that the alternative of ‘natural’ morbidity caused by the coronavirus puts a person at significant, higher, and much more common risk of serious adverse events,” Balicer said.
The results of this real-world study confirm, complement, and build on the previously reported findings of the Pfizer/BioNTech phase 3 randomized clinical trial, which involved 21,720 individuals, the researchers noted.
The comprehensive nature of this new analysis and the sheer volume of data involved offer a more detailed assessment of the vaccine’s safety across a wider range of adverse events.
“These data should facilitate informed individual risk-benefit decision-making, and, in our view, make a strong argument in favor of opting in to get vaccinated, especially in countries where the virus is currently widespread,” added Balicer, who also serves as chairman of Israel’s National Expert Advisory Team on COVID-19 response.
Previous efforts to characterize vaccine safety have relied on voluntary active reporting by vaccinated individuals, known to be incomplete. The new study relies on the analysis of millions of anonymized electronic medical records, which are far more comprehensive.
Parallel analyses
In an effort to provide the proper context that is critical for interpreting vaccine safety findings, the researchers also examine a wide range of adverse events both among vaccinated individuals and among unvaccinated individuals who were infected with the coronavirus, conducting two parallel analyses, assessing the occurrence of 25 adverse events in each of these groups.
In the vaccinated subgroup, the researchers compared the outcomes of 884,828 vaccinated individuals 16 years and older with those of 884,828 unvaccinated individuals based on an extensive set of sociodemographic, geographic, and health-related characteristics.
This analysis took place from Dec. 20, 2020, the launch of Israel’s national vaccination campaign, through May 24, 2021.
Some individuals switched groups based on their changing vaccination status, with 235,541 people moving from the unvaccinated group into the vaccinated group during the study.
To provide context for the vaccine safety findings above, a separate analysis was conducted among unvaccinated individuals. This analysis estimated rates of the same 25 potential adverse events among 173,106 unvaccinated individuals who were infected with SARS-CoV-2, compared with 173,106 carefully matched controls not infected with SARS-CoV-2.
This analysis took place from March 1, 2020, the beginning of the COVID-19 pandemic in Israel, through May 24, 2021.
The vaccine was found to be safe: Out of 25 potential side effects examined. four were found to have a link with the vaccine.
Myocarditis, an inflammation of the heart muscle associated with the vaccine was rare—2.7 excess cases per 100,000 vaccinated individuals. These events were observed mainly among males between the ages of 20 and 34.
In contrast, myocarditis was far more common among unvaccinated individuals infected with SARS-CoV-2. The analysis showed 11 excess cases of myocarditis per 100,000 infected individuals.
Other adverse events moderately associated with vaccination were swelling of the lymph nodes, a mild side effect that is part of a standard immune response to vaccination, with 78 excess cases per 100,000, appendicitis with 5 excess cases per 100,000, likely as a result of swelling of lymph nodes around the appendix.
Reactivation of dormant herpes zoster (chickenpox virus) infection occurred in 16 cases per 100,000.
Unvaccinated risks
These small numbers of adverse events among vaccinated individuals stood in stark contrast with the high rate of multiple and more serious adverse events among unvaccinated individuals infected with SARS-CoV-2.
These included cardiac arrhythmias (a 3.8-fold increase above baseline risk with 166 cases per 100,000 infected patients); kidney damage (14.8-fold increase with 125 excess cases per 100,000); pericarditis (5.4-fold increase with 11 excess cases per 100,000); pulmonary embolism (12.1-fold increase with 62 excess cases per 100,000); deep-vein thrombosis, or a blood clot in the veins (3.8-fold increase with 43 excess cases per 100,000); myocardial infarction, or heart attack (4.5-fold increase with 25 excess cases per 100,000); and stroke (2.1-fold increase with 14 excess cases per 100,000).
Additional investigators on the study included Noam Barda, Noa Dagan, Yair Ben-Shlomo, Eldad Kepten, Jacob Waxman, Reut Ohana, all of the Clalit Research Institute; Doron Netzer of Clalit Health Services; Miguel Hernán and Marc Lipsitch of the Harvard T.H. Chan School of Public Health; and Isaac Kohane of Harvard Medical School.
The research was funded in part by the newly announced Ivan and Francesca Berkowitz Family Living Laboratory Collaboration at Harvard Medical School and Clalit Research Institute.
Relevant disclosures: Marc Lipsitch receives support from the Morris-Singer Fund.
Disclosure forms provided by the authors are available with the full text of this article at NEJM.org.
Adapted from a Clalit Research Institute news release
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Vaccine Research & Development
How can covid-19 vaccine development be done quickly and safely, typical vaccine development timeline.
- Each clinical trial phase follows completion of the prior phase
- Can take a long time to accumulate cases to assess vaccine efficacy outside pandemic
- Manufacturing capacity is scaled-up after phase III trial and regulatory approval
Accelerated timeline in a pandemic
- Some clinical trial phases are combined
- Cases accumulate rapidly to assess vaccine efficacy because of the pandemic
- Manufacturing capacity is scaled up during the clinical trials but at financial risk
Typical Timeline
A typical vaccine development timeline takes 5 to 10 years, and sometimes longer, to assess whether the vaccine is safe and efficacious in clinical trials, complete the regulatory approval processes, and manufacture sufficient quantity of vaccine doses for widespread distribution.
to the Accelerated Timeline
Preclinical Trials
Preclinical testing of vaccine candidates typically starts in animal models, first in small mammals such as mice or rats and then non-human primates such as monkeys. Preclinical studies are important for eliminating potential vaccines that are either toxic or do not induce protective immune responses. But many vaccines that appear to be safe and induce protective immune responses in animals fail in human studies. Only vaccine candidates that are very promising in preclinical testing move forward into phase I clinical trials.
Phase I Clinical Trials to Assess Safety, Dosing, and Immune Responses
Phase I clinical trials are the first step in assessing vaccines in people. Typically involving one to several dozen healthy volunteers, phase I trials assess short-term safety (e.g., soreness at the site of injection, fever, muscle aches) and immune responses, often with different vaccine dosages. Only if a vaccine candidate is shown to be safe in phase I trials will it move to larger phase II trials.
Phase 1 trials can be completed in two to three months, allowing for two doses of a vaccine three to four weeks apart
Phase II Clinical Trials to Assess Safety and Immune Responses
Phase II clinical trials continue to assess safety and immune responses but in a larger number and more diverse group of volunteers, typically one to several hundred people. Phase II trials may include target populations of a specific age or sex, or those with underlying medical conditions. Vaccines for children start with adult volunteers and move to progressively younger groups of children. Different types of immune responses are often measured, including antibodies and cell-mediated immunity, but phase II trials do not assess how well a vaccine actually works. Only in phase III trials is vaccine efficacy assessed.
Phase 2 trials can be completed in three to four months, allowing for longer follow-up to better assess safety and immunogenicity. This timeline is shortened when phase 1 and phase 2 trials are combined.
Phase III Clinical Trials to Assess Safety and Efficacy
Phase III clinical trials are critical to understanding whether vaccines are safe and effective. Phase III trials often include tens of thousands of volunteers. Participants are chosen at random to receive the vaccine or a placebo. In Phase III, participants and most of the study investigators do not know who has received the vaccine and who received the placebo. Participants are then followed to see how many in each group get the disease. Assessing short- and long-term safety is also a major goal of phase 3 trials.
Phase 3 trials may take six to nine months to allow early assessment of safety and efficacy, particularly if conducted in areas with a high risk of infection, but with follow-up continuing for two years or more to assess long-term safety and efficacy.
Regulatory Approval Process
Each country has a regulatory approval process for vaccines. In the United States, the Food and Drug Administration (FDA) is responsible for regulating vaccines. In situations when there is good scientific reason to believe that a vaccine is safe and is likely to prevent disease, the FDA may authorize its use through an Emergency Use Authorization (EAU) even if definitive proof of the efficacy of the vaccine is not known, especially for diseases that cause high mortality.
Scaling Up Vaccine Manufacturing
Scaling up vaccine manufacturing is typically done near the end of the regulatory process because of the huge financial investment needed. In the United States, the FDA will inspect the manufacturing facilities. The cost of developing a new vaccine can be several billion U.S. dollars prior to the scale up of manufacturing facilities.
Post-Licensure Vaccine Safety Monitoring
After a vaccine is approved and in widespread use, it is critically important to continue to monitor vaccine safety. Some very rare side effects may only be detectable when large numbers of people have been vaccinated. Safety concerns that are discovered at this late stage could lead a licensed vaccine to be withdrawn from use, although this is very rare.
Article misleads on safety of Pfizer vaccine ingredient
An article and social media posts claim an ingredient in pfizer's covid-19 vaccine is not safe for humans, citing a data sheet from a us chemical corporation. this is misleading; the company says it does not manufacture the compound in the shot -- and the document pertains to research-grade chemicals, which health experts say do not undergo the same strict regulatory approval process..
"The package insert for Pfizer Inc's mRNA vaccine reveals the drug contains an ingredient listed as '[n]ot for human or veterinary diagnostic or therapeutic use in a technical data sheet referencing the US Occupational Safety and Health Administration (OSHA),'" says a February 7, 2023 article .
The article goes on to conflate the vaccine ingredient with a compound that Cayman Chemical , an American biotechnology company, produces for health research.
Screenshot of an article taken February 15, 2023
The report comes from American Faith, a website founded by Phil Hotsenpiller , a pastor in the US state of California. His site has previously promoted debunked claims about Covid-19 treatments and vaccines .
The article's claim, examples of which date back to at least 2022, spread quickly on social media platforms such as Instagram and Twitter . But the Pfizer vaccine ingredient is not the same as Cayman Chemical's compound.
"We do not make ALC-0315 for pharmaceutical use," said Ryan Foster, a Cayman Chemical spokesperson, in a February 15 email.
What is the ingredient?
ALC-0315 is part of a lipid nanoparticle that helps shield the fragile messenger RNA (mRNA) molecules that Pfizer's Covid-19 vaccine delivers to cells.
"The RNA vaccine can't just be injected into the body, then it would break down immediately. It must be protected with a cover," Annette Beck-Sickinger , professor of biochemistry and bioorganic chemistry at the University of Leipzig in Germany, previously told AFP. "This shell is a mixture of different lipids (fat molecules), which then form small globules like a kind of 'soap bubble.'"
Fact sheets from the US Food and Drug Administration (FDA), the Public Health Agency of Canada and the European Medicines Agency (EMA) list ALC-0315 as a component of the Pfizer-BioNTech Comirnaty vaccine .
This screenshot taken February 24, 2023 shows the Pfizer Covid-19 vaccine ingredient list on the FDA's website
"The manufacturing process and controls for Comirnaty have been well characterized and qualified," the FDA told AFP in a February 21 email. "The analytical procedures include tests to ensure vaccine safety, identity, purity, quality and potency."
A Pfizer spokeswoman told AFP she would not comment on non-Pfizer documents, instead pointing to the EMA fact sheet when asked about the safety of specific ingredients.
Cayman Chemical's compound
A safety data sheet from Cayman Chemical does say its ALC-0315 product is "for research use" and "not for human or veterinary diagnostic or therapeutic use."
Screenshot of a Cayman Chemical safety data sheet taken February 16, 2023
But Raymond Tellier , a microbiologist at the McGill University Health Center in Canada, said it is important to note the other ingredients listed in the compound.
In addition to ALC-0315, the document shows the Cayman Chemical product is comprised of 95 percent ethanol , a volatile, flammable and toxic compound.
Screenshot of a Cayman Chemical safety data sheet taken February 23, 2023
Tellier said that because lipids may not be water soluble, companies "dissolve them in an organic solvent."
"In the case of Cayman Chemical, they choose ethanol," he said in a February 16 email. "But in the final formulation of the vaccine, there is no ethanol."
In 2021, Cayman Chemical addressed similar misinformation about another compound that academics and scientists use to research health therapies.
"Chemicals under the same name can have differing designations such as grade or formulation that are defined by their manufacturing protocols and intended use," the company said in a press release.
Tellier said that is an important distinction.
"What they say is that their product 'is not for human or veterinary diagnostic or therapeutic use,'" he said. "The reason is simply that Cayman Chemical manufactures reagents for research labs and sells only to research labs; if you want to sell for other uses such as diagnostic or therapeutic uses there are many more regulatory and safety procedures to go through."
Companies that manufacture active pharmaceutical ingredients in the US must adhere to strict federal guidelines to ensure their safety for human and veterinary use. The Paul-Ehrlich-Institut , which regulates vaccines in Germany, has also addressed the difference between laboratory and pharmaceutical ingredients on its website.
All of AFP's reporting on vaccine misinformation is available here .
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Jailed Malaysia ex-PM Najib acquitted in latest 1MDB trial
Malaysian former Prime Minister Najib Razak was acquitted Friday in the latest trial in response to the multibillion-dollar looting of the 1Malaysia Development Berhad state fund. Najib, who is serving a 12-year prison term after losing the final appeal in his first of several corruption trials linked to the 1MDB scandal, was found not guilty on the charge of tampering with an audit report to cover up wrongdoings. Defense lawyer Mohamad Shafee Abdullah said the High Court ruled that prosecutors did not have sufficient evidence to prove Najib guilty of abusing his position as Prime Minister and Finance Minister to order amendments to the 1MDB audit report in 2016 before it was presented to Parliament.
Audience in Delhi openly laughs as Lavrov says Ukraine war ‘launched against’ Russia
‘You know, the war, which we are trying to stop, which was launched against us,’ says Russian foreign minister
Donnie Yen got John Wick name changed to avoid Asian stereotypes
Donnie Yen got John Wick name changed to avoid Asian stereotypes.
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Watch: Belarusian resistance releases video of drone landing on damaged Russian spy plane
The Belarusian partisans behind the claimed sabotage of a rare Russian spy plane last week have released footage purporting to show an audacious drone mission over the airfield.
Man Utd tipped to axe midfielder if Erik ten Hag recruits €85m ‘super talent’ from Barcelona
Danny Murphy thinks Erik ten Hag will stop playing Christian Eriksen if Man Utd are able to sign Frenkie de Jong from FC Barcelona this summer.
Olivia Rodrigo just wore the same piece Carrie Bradshaw repped back in 2001
Olivia Rodrigo wears a leather boob tube and horse trousers, once worn by Carrie Bradshaw, to the 2023 Billboard Women in Music Awards.
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Contestant's Bagel Fail On 'Wheel Of Fortune' Leaves A Hole In Our Hearts
She faced a schmear campaign for her bagel blunder on the game show this week.
Drugs, jacuzzis and a horse: the anarchic Philippines prison where anything can be bought
After raids at the New Bilibid prison identified thousands of contraband goods, the management of the country’s prisons is in the spotlight
RAF to fly first Nato missions with Germany over Estonia in show of strength to Russia
The RAF will fly Nato missions with Germany over Estonia for the first time in a show of strength to Russia.
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Royal Navy seized Iranian anti-tank missiles in daring night-time helicopter raid
The Royal Navy seized Iranian anti-tank missiles in a night-time helicopter raid last month, working with the US to intercept the smuggling vessel.
Putin accuses Ukrainians of attack inside Russia – but Kyiv calls it ‘provocation’
Russia’s border regions have been increasingly volatile since the invasion
Secret millionaire claims his parents would disown him ‘if they found out’
Giuseppe Fiorentino has millions in the bank but has never told his Italian family as he believes they would “disown” him
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Ex-Man Utd player gives seven reasons Ten Hag should sign Spurs man who ‘could help a lot’
Former Man Utd midfielder Kleberson believes his compatriot Richarlison "should have" joined the Red Devils "instead of Tottenham" last summer.
Belgian mother who killed five children euthanised 16 years on
A Belgian woman who murdered her five children in a case that shocked the country has been euthanised at her own request, 16 years to the day after their killing, her lawyer said Thursday. Belgian law allows for people to chose to be euthanised if they are deemed to be suffering from "unbearable" psychological, and not just physical, suffering that cannot be healed.
Prince Harry and Meghan Markle Reportedly Weren't Told Prince Andrew Would Be Getting Frogmore Cottage
Talks are reportedly ongoing between the Sussexes and King Charles over Frogmore, but news that the King offered their home to Prince Andrew has disrupted the negotiations.
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SMRT files police report after boy allegedly caused train delay by jamming screen door
SMRT filed a police report on a boy after he allegedly caused a train delay by jamming platform screen doors at Jurong East MRT station.
Wagner chief calls on Zelenskiy to abandon ‘encircled’ Bakhmut
Yevgeny Prigozhin says his troops are fighting against old men and children in besieged eastern Ukraine town
3 Singapore Blue-Chip Stocks Doubling Their Dividends in 2023
News of a dividend increase is always music to an investor’s ears. Here are three stocks that doubled their dividend payments. The post <strong>3 Singapore Blue-Chip Stocks Doubling Their Dividends in 2023</strong> appeared first on The Smart Investor.
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Vaccine Safety Research and Safety Studies The United States’ long-standing vaccine safety system ensures vaccines are as safe as possible. As science advances and new information becomes available, this system will continue to improve. Vaccine safety research: Ensures the benefits of vaccines approved in the U.S. outweigh the risks.
From December 2020 to December 2021, about 470 million doses of COVID-19 vaccine have been given in the U.S. Roughly 12 months of data, including data from tens of thousands of participants in clinical trials, show that the vaccines are safe and effective at preventing serious disease or death due to COVID-19.
It is clear that coronavirus vaccines are safe and effective, but as more are rolled out, researchers are learning about the extent and nature of side effects. Ariana Remmel Older people have...
The research, which assessed the safety of the Pfizer/BioNTech BNT162b2 mRNA vaccine, is based on analysis of data from nearly 2 million individuals in Israel and represents one of the largest real-world assessments of COVID-19 vaccine safety to date.
Phase I clinical trials are the first step in assessing vaccines in people. Typically involving one to several dozen healthy volunteers, phase I trials assess short-term safety (e.g., soreness at the site of injection, fever, muscle aches) and immune responses, often with different vaccine dosages.
An article and social media posts claim an ingredient in Pfizer's Covid-19 vaccine is not safe for humans, citing a data sheet from a US chemical corporation. This is misleading; the company says it does not manufacture the compound in the shot -- and the document pertains to research-grade chemicals, which health experts say do not undergo the same strict regulatory approval process."The ...