Could Future Vaccines Be More Effective Against Onward Transmission
Again, first generation covid vaccines were evaluated against reducing hospital admissions and death in the challenging first year of the pandemic. They wouldnt have been expected to generate sterilising immunity and block transmission. But, says Singanayagam, now that we have a suite of vaccines using different approaches, there is some opportunity to think about future jabs for different situations.
There are avenues to think about the development of vaccines that can have more of an effect on transmission, she says. Those are usually vaccines delivered more locally, such as directly through the respiratory tract, which could tackle the source of major transmission, rather than the lungs, which is where the first generation of vaccines was targeted in order to prevent severe infection. Thats probably the way things will move in the future.
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Will I Be Protected After Just One Dose
While some protection may be conferred after a single dose of the Pfizer-BioNTech and Moderna mRNA vaccines, this protection is far less than after two doses. The second dose acts as a booster, better preparing the immune system to fight infection. All people should receive two doses of these vaccines.
Could Taking Two Different Vaccines Boost The Effectiveness
Currently, the Centers for Disease Control and Prevention recommends getting two doses of the same mRNA vaccine unless the supply does not allow for them to get the second dose of the same brand.
People are also recommended to get the same brand for the third dose of mRNA vaccine if they are receiving it because of an immune-compromising condition. However, if they are receiving a second dose following J& J/Janssen or a third dose following mRNA as a booster, they can get a different type if they so choose.
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How Did The Vaccine Companies Decide Which Mrna To Use
In order for a virus to reproduce and cause infection, it must get into cells and take over the cellular machinery. Because viruses attach to cells using a particular protein on their surface, in this case the SARS-CoV-2 spike protein, scientists understood that blocking that attachment would be a direct way to prevent infection. One way to block this attachment is with antibodies that bind to the surface protein. As such, when the genome was published, scientists developing the nucleic acid or protein subunit vaccines chose the gene for the spike protein, anticipating that this would be the most direct route to developing an effective vaccine.
Should I Get The Vaccine For Influenza
Yes, it is very important to get the influenza vaccine, particularly this season when both influenza viruses and SARS-CoV-2 can infect people. We still do not know how these two viruses will interact but people can get infected with both viruses and this will likely cause more severe disease and possibly death. Reducing the number of people who get severe influenza and require hospitalization will also help ensure that the health care system, hospitals and intensive care units will not be overwhelmed should there be an increase in Covid-19 cases this fall and winter.
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What About The Other Vaccines
Lab studies of other COVID-19 vaccines from Moderna Inc , AstraZeneca Plc and Johnson & Johnson are also underway. Those studies analyze the impact of the Omicron variant on blood samples from previously infected and vaccinated people. Many scientists expect these shots also will show a reduction in their ability to neutralize Omicron compared with earlier coronavirus variants.
Moderna’s shot uses similar technology as Pfizer/BioNTech’s, but has been shown to offer more durable protection against infection with previous variants, a benefit believed to be due to its higher dose and longer interval between shots. Moderna may see less of a drop in neutralizing antibodies compared with Pfizer, Adalja said.
What is the World Economic Forum doing about access to vaccines?
The aim of Gavi is to make vaccines more accessible and affordable for all – wherever people live in the world.
Along with saving an estimated 10 million lives worldwide in less than 20 years,through the vaccination of nearly 700 million children, – Gavi has most recently ensured a life-saving vaccine for Ebola.
At Davos 2016, we announced Gavi’s partnership with Merck to make the life-saving Ebola vaccine a reality.
“I suspect you’ll see a diminution in all of them,” Adalja said.
Q: What Is The Most Current Information Pertaining To The Risk For The Occurrence Of Blood Clots In Combination With Low Blood Platelets After Receiving The Janssen Covid
A: Currently available evidence supports a causal relationship between blood clots in combination with low blood platelets ) and the Janssen COVID-19 Vaccine. The FDA continues to find the known and potential benefits of the Janssen COVID-19 Vaccine outweigh its known and potential risks in individuals 18 years of age and older.
In people who have developed blood clots with low blood platelets following the Janssen COVID-19 Vaccine, symptoms began approximately 1 to 2 weeks following vaccination. Reporting of these blood clots with low blood platelets have been reported in males and females, in a wide age range of individuals 18 years of age and older, with the highest reporting rate in females ages 30- 49 years , and about 1 out of every 7 cases has been fatal.
You should contact your health care provider immediately if you are experiencing any of the following symptoms after receiving the Janssen COVID-19 Vaccine:
- shortness of breath
- severe or persistent headaches or blurred vision
- easy bruising
- tiny blood spots under the skin beyond the site of injection of the vaccine
These symptoms are different from the commonly reported side effects that people may experience in the first few days following vaccination, which can include headache, fatigue, muscle aches and nausea. Most of these side effects are mild to moderate in severity and last 1 to 2 days.
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Does A Vaccinated Person Present A Risk To Unvaccinated Family Members In The Same House
Vaccinated people do not shed virus as a result of vaccination. Neither the mRNA nor the adenovirus vaccines are composed of live viruses, so there is no infectious virus to spread from a vaccinated person to someone else.
But a vaccinated person who encounters the virus can still experience what is referred to as asymptomatic infection. An asymptomatic infection occurs when a person is exposed to the virus in the community and the virus can still replicate in their body, but they dont have symptoms because their immune system stifles the infection as a result of vaccination. In this scenario, the person could potentially spread the virus without even knowing they are infected. While it is not anticipated that vaccinated individuals would be a source of significant spread of the virus, they may still spread the virus in a limited manner. Therefore, we need to practice caution.
Given that young children and possibly family members and friends will not all be vaccinated, vaccinated individuals should continue to follow public health guidance when they are out in the community to decrease spread of the virus. Even when a whole family is vaccinated, continuing to practice these measures will be important for two reasons:
Read more in the January 2021 Parents PACK newsletter article, When the Whole Family Has Not Yet Been Vaccinated Against COVID-19.
Do Covid Vaccines Prevent Transmission Of The Virus
Studies show that while both the vaccinated and unvaccinated can have similar levels of the virus in their bodies, the vaccinated are less likely to pass it on to others. Plus, COVID toes and a pill to treat COVID at home.
It has long been established that COVID-19 vaccines reduce the risk of serious illness and hospitalisation. But there has until recently been a question mark over whether they reduce transmission of the virus.
It is an important question and one around which public health policies have been built. The United Kingdom, for example, has mandated COVID vaccines for all social care staff to protect the vulnerable people they care for they are set to do the same for NHS staff. And in Italy, from October 15, workers will have to show proof of vaccination, a negative COVID test or recovery from a recent infection to their employer. Anyone unable to do this risks being suspended from work without pay. Other countries are adopting similar measures.
But do vaccines actually limit the spread of the virus?
Those who are vaccinated will have primed immune systems that will recognise the coronavirus far quicker and be able to rid their body of it faster than those who are unvaccinated.
It is important to remember that those who are vaccinated will have primed immune systems that will recognise the coronavirus far quicker and be able to rid their body of it faster than those who are unvaccinated and whose immune system will take time to respond to the virus.
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Do I Need Another Dose Of The Covid
J& J/Janssen adenovirus vector vaccine
People who received the J& J/Janssen vaccine should get a second dose of vaccine separated by at least 8 weeks, regardless of their health status. They are not currently recommended to get a third dose of the J& J/Janssen vaccine.
Pfizer or Moderna mRNA vaccine
A third dose of COVID-19 mRNA vaccine may be recommended for one of two reasons:
- To address waning immunity, traditionally called a booster dose.
- To enhance the immune response of an individual who did not develop sufficient immunity following receipt of the recommended number of doses of COVID-19. In this case, the third dose can be considered as an additional primary dose.
How the third dose is implemented will be affected by which of these reasons are the cause for the additional dose.
In the case of COVID-19 vaccines, most people who received mRNA vaccines do not currently need an additional dose. However, the Centers for Disease Control and Prevention has either recommended, or is allowing, a third dose of mRNA vaccine for particular groups of people, including:
Those getting an additional primary dose should get the same type and dose of vaccine they received initially when possible.
Those getting a booster dose can get any type of vaccine. Importantly, booster doses of Moderna should be half the quantity of the primary dose. Pfizer booster doses are the same quantity as the primary dose .
People in this category include the following:
Q: What Revisions To The Fact Sheets Did The Fda Announce On December 14 2021 Pertaining To The Occurrence Of Blood Clots In Combination With Low Blood Platelets After Administration Of The Janssen Covid
A: Monitoring the safety of the Janssen COVID-19 Vaccine continues and reports to the Vaccine Adverse Events Reporting System , a passive surveillance system, provide evidence for an increased risk of blood clots in combination with low blood platelets ) with onset of symptoms approximately one to two weeks after administration of the Janssen COVID-19 Vaccine.
The Fact Sheet for Healthcare Providers Administering Vaccine has been revised to include a Contraindication to the administration of the Janssen COVID-19 Vaccine to individuals with a history of thrombosis with thrombocytopenia following the Janssen COVID-19 Vaccine or any other adenovirus-vectored COVID-19 vaccine, such as AstraZenecas COVID-19 vaccine . The Warning section has been updated to include the most current information about the risk of TTS following administration of the Janssen COVID-19 Vaccine. Specifically, it informs that cases of TTS following administration of the Janssen COVID-19 Vaccine have been reported in males and females, in a wide age range of individuals 18 years of age and older, with the highest reporting rate in females ages 30- 49 years , and about 15% of cases have been fatal. The Fact Sheet has been revised to also convey that currently available evidence supports a causal relationship between TTS and the Janssen COVID19 Vaccine.
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What If I Cant Get The Second Dose 21 Or 28 Days After The First Dose
The Centers for Disease Control and Prevention allows for a 4-day grace period when assessing on-time receipt. This means the following ranges of days are considered on-time for receipt of the second dose:
- Pfizer vaccine: 17 to 25 days after the first dose
- Moderna vaccine: 24 to 32 days after the first dose
People should try to get the second dose during this period or as soon after as possible. However, if your second dose is given later than this, you do not need to restart the vaccine. You still only need to get the second dose. However, it is important to note that the first dose did not protect as many people as were protected after the second dose, so if you are exposed to SARS-CoV-2 during the delay, you may or may not have enough immunity to prevent you from experiencing symptoms.
Q: Why Did The Fda And Cdc Recommend A Pause In The Use Of The Janssen Covid
A: As a result of ongoing safety monitoring, on April 13, 2021, the FDA and CDC recommended a temporary pause in the use of Janssen COVID-19 Vaccine, due to reports of a serious and rare type of blood clot in combination with low blood platelets . This serious condition is called thrombosis with thrombocytopenia syndrome .
Out of an abundance of caution, the FDA and CDC recommended a pause in the use of the Janssen COVID-19 Vaccine while the FDA and CDC investigated these reports of serious adverse events. This was important, in part, to help ensure that health care providers were made aware of the potential for these adverse events and could plan for proper recognition and management due to the unique treatment required for TTS.
The safety monitoring program that is in place to monitor COVID-19 vaccines is working, as we were able to detect the reports of these serious adverse events early and take action to assess them.
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How Much Protection Could Vaccines Offer According To The Studies That Found Benefit
Some study results suggest substantial protection, while others find only a slight benefit.
One large study of electronic records of patients in the U.S. Veterans Health Administration found that vaccinated Covid patients had only a 13 percent lower risk than unvaccinated patients of having symptoms six months later.
Two studies in Britain found a bigger effect. One study of about 1.2 million people, based on patients reports via a phone app, found a 50 percent lower risk of lingering symptoms among vaccinated patients. Another, which has not been peer-reviewed and was based on surveying about 6,000 patients, found a 41 percent lower risk.
A study of U.S. patients by Arcadia, a health care data firm, and the Covid Patient Recovery Alliance, a collaboration of leaders with health expertise in government and the private sector, found a larger benefit still. The study, which has not been peer-reviewed, analyzed records of about 240,000 patients infected with the coronavirus by May 2021 and found that those who had received even one dose of a Covid vaccine before their infection were one-seventh to one-tenth as likely to report two or more symptoms of long Covid 12 to 20 weeks later. That study also found that people who received their first vaccine dose after contracting the coronavirus were less likely to develop long Covid than those who remained unvaccinated, and the sooner they were vaccinated after infection, the lower the risk of long-term symptoms.
How Will A Vaccine Prevent Covid
The coronavirus that causes COVID-19 has spikes of protein on each viral particle. These spikes help the viruses attach to cells and cause disease. Some of the coronavirus vaccines are designed to help the body recognize these spike proteins and fight the coronavirus that has them.
An effective vaccine will protect someone who receives it by lowering the chance of getting COVID-19 if the person encounters the coronavirus. More important is whether the vaccine prevents serious illness, hospitalization and death. At this time, all three vaccines are highly efficacious at preventing serious illness, hospitalization and death from COVID-19. Widespread vaccination means the coronavirus will not infect as many people. This will limit spread through communities and will restrict the viruss opportunity to continue to mutate into new variants.
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What Evidence Do We Have That Covid
Most papers to date indicate vaccines are holding up against admission to hospital and mortality, says Linda Bauld, professor of public health at the University of Edinburgh, but not so much against transmission.
The first weekly covid-19 vaccine surveillance report for 20221 from the UK Health Security Agency was more positive than Baulds assessmentbut didnt say outright that covid-19 vaccines prevent transmission. Several studies have provided evidence that vaccines are effective at preventing infection, it states, Uninfected people cannot transmit therefore, the vaccines are also effective at preventing transmission.
A study2 of covid-19 transmission within English households using data gathered in early 2021 found that even a single dose of a covid-19 vaccine reduced the likelihood of household transmission by 40-50%. This was supported by a study of household transmission among Scottish healthcare workers conducted between December 2020 and March 2021.3 Both studies analysed the impact of vaccination on transmission of the variant of SARS-CoV-2, which was dominant at the time.
A subsequent study,4 conducted later in the course of the pandemic when the delta variant was dominant, showed vaccines had a less pronounced effect on denting onward transmission, but were still effective.