Effectiveness Against New Strains
The COVID-19 virus has changed over time due to mutations that result in a different strain of the virus. This is common for viruses, but some changes have greater impact than others. They may spread more rapidly, cause more or less serious illness, or fail to respond to the existing vaccines.
The CDC will classify some strains as a “variant of concern” when they have the potential for this greater impact. As of December 2021, there were two variants of concern in the U.S. They were:
- Omicron first identified in Botswana and South Africa
- Delta first identified in India
What Are The Symptoms
Right now, there aren’t any reports that show BA.5 is giving people different symptoms compared to earlier versions of omicron.
For many people who become sick with COVID-19 these days , symptoms resemble cold symptoms such as sore throat, runny nose and fatigue. Back pain is a peculiar new symptom of COVID-19 that some people with omicron have reported, and the once very common loss of taste or smell appears to be much less common with omicron variants than with older strains.
If you have symptoms and are wondering whether it’s COVID-19, taking a test and staying home while you’re sick will help protect people more vulnerable to severe COVID-19 disease.
How To Check Youre Up To Date With Your Boosters
The best way to check you are up to date with polio vaccinations is to contact your GP, as your medical records will state whether or not you received the immunisations as a child.
Ring your doctors surgery to ask for your full records. You can also request they be added to your NHS account, viewable via the app or website. Accounts can be .
Youll only have access to your allergy information and notes on medications you take at first, notes the NHS but you can request to have your full medical records put online.
They can also be added to other digital GP services, but again youll have to ask for the full record to be made available.
Some may also be in possession of a vaccine record book from childhood, which would detail your jabs.
If youve had a booster vaccine for travel privately as an adult, this information may not be stored by your GP.
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Who Is Eligible For A Covid
According to the CDC and FDA, the following groups of people are eligible for COVID-19 vaccine boosters or third doses:
- People with compromised immune systems ages 5 and older: The CDC recommends that people with moderately to severely compromised immune systems receive an additional dose of mRNA COVID-19 vaccine at least 28 days after a second dose. This is for the Pfizer or Moderna COVID-19 vaccines. Pfizer remains the only approved vaccine for ages 5-17. People with moderately to severely compromised immune systems who received the Johnson & Johnson vaccine may also receive an mRNA COVID-19 vaccine as an additional dose at least 28 days after the first dose.
- A booster dose is also recommended for ages 12 and older who are immunocompromised. This dose would be given at least three months after the additional primary shot . For those who received the Pfizer or Moderna vaccines, this booster dose would be given at least three months after the additional primary shot . For those who received the Johnson & Johnson vaccine, this booster dose would be given at least two months after the Pfizer or Moderna shot.
If I Wait Longer Than The Recommended 3

Both Pfizer/BioNTech and Moderna advised against delaying the second dose if at all possible. However, like with other vaccines, the second COVID-19 vaccination is a booster shot. This increases your level of protection by further teaching your body what the virus looks like, so it can respond quickly. As with other vaccinations, theres no indication that a delay in receiving the booster shot reduces effectiveness. Delaying the second dose will delay full protection. However, people who receive the second dose at any time after the recommended date can be considered fully vaccinated.
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Covid Vaccines Provide Protection But Immunity Wanes Over Time Researchers Found A Drop From 83% After The First Month To 22% After Five Or More Months
Protection against symptomatic COVID-19 begins to decrease after one month from initial vaccination, while immunity against severe COVID-19 remains high for about six months, according to a new study.
For the study, researchers analyzed data from 7 million unvaccinated and vaccinated people. The latter received Pfizer-BioNTech, Moderna, or Johnson & Johnson doses of the COVID-19 vaccine. Conducting a systematic review and meta-analysis, the investigators examined 18 peer-reviewed studies published from December 2019 to November 2021, prior to emergence of the Omicron variant that dominated the most recent pandemic surge in the US.
According to the Centers for Disease Control and Prevention, more than 577 million doses of the COVID-19 vaccine have been administered across the nation. Vaccinated individuals may wonder how long the vaccine provides protection against the coronavirus.
The research shows the vaccines provided significant protection against COVID-19, but effectiveness waned over time. After full vaccination, immunity against COVID-19 infection decreased from 83% after the first month to 22% after five or more months.
The research included data on adults and children, aged 12 and older. The findings showed that recipients of the Moderna vaccine experienced the highest levels of protection.
Future studies should focus on showing how vaccine protection lasts for various comorbidities and immune suppression status.
Video Answer: Dog Vaccine Update
Haemorrhagic gastroenteritis is a condition that causes vomiting and diarrhoea that contains blood. Specialists suspect it’s caused by a nasty bacteria that attacks the lining of the guts. Symptoms of HGE usually last 2-4 days and most dogs make a good recovery if they recieve veterinary treatment quickly.
If your dog is diagnosed with giardia, he will likely be prescribed medication, and your veterinarian will recommend a follow-up fecal sample two weeks after treatment.
A dog should be bathed on his last day of treatment to eliminate all giardia cysts from his hair coat.
It is often painful and can last as long as 18 months, though more commonly it lasts from 2 to 5 months.
Pano in dogs is characterized by lameness that often comes and goes and changes from leg to leg.
It is a common problem in several large breeds and the cause is currently unknown.
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Further Research To Be Conducted On Long Covid
Many consumers who become infected by COVID-19 eventually recover from their symptoms and can resume normal life. But there are some people out there who experience lasting symptoms from the virus a condition that has been called long COVID.
This week, President Biden directed the Health and Human Services Department to put together a plan to research long COVID to bolster diagnosis and treatment efforts. HHS Secretary Xavier Becerra said he has plans for any additional funding that is granted by lawmakers.
If we receive additional financial support for it from Congress, we will launch new centers of excellence in communities across the country to provide high quality care to individuals experiencing long Covid, he stated.
Where Does The Vaccine Go
Here’s a peer-reviewed study that shows where intramuscular vaccines travel in macaques . Vaccines mostly remain near the site of injection and local lymph nodes.
This makes sense: Lymph nodes produce white blood cells and antibodies to protect us from disease. A key part of the lymphatic system, lymph nodes also clean up fluids and remove waste materials. Finding pieces of spike protein in the lymph nodes is completely normal, because lymph nodes act as the trash removal service for the body. That means the vaccine did its job and will be cleared from the body.
Another peer-reviewed study tested exactly where an mRNA vaccine went in mice. Most of the mRNA vaccine stayed in the injection site muscle where you get the shot. Look at Table 1. A lot of mRNA vaccine was found in local lymph nodes, which peaked about eight hours after the shot was given. A much smaller amount of mRNA vaccine went to farther away lymph nodes.
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Get The Vaccine The Authors Recommend
“We didn’t set out to compare the effectiveness of vaccination in people with and without a history of infection, but when we looked at the data we could see an effect,” co-first author , an assistant professor of medicine, said. “If you’ve already been infected and then you get vaccinated, you get a boost to your antibody levels. The vaccine clearly adds benefit, even in the context of prior infection, which is why we recommend that people who have had COVID-19 get the vaccine.”
How Long Does The Polio Vaccine Last
The vaccine protects you for 10 years and you will need a booster to remain protected after this time.
Polio has been rare in the UK so most people only get boosters when travelling to countries with a risk of polio.
There are only two countries in which polio is considered endemic – meaning it is regularly found – and those are Afghanistan and Pakistan.
Check before travelling if you need to get the booster, especially to parts of Asia or Africa, and remember you will need this at least two weeks before you go.
If it’s your first jab, you will need several doses in order to be fully vaccinated so factor time to allow for this or your holiday may be cancelled.
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Q: What Is The Benefit Of Vaccinating Individuals Who Have Had Covid
A: Multiple studies have shown that previously infected individuals mount a robust immune response following receipt of COVID-19 vaccines, even after just a single dose. Furthermore, there are accumulating data that vaccination after prior infection can boost immune responses against SARS-CoV-2 variants of concern in fact, the vaccine response in previously infected individuals may be superior to that in individuals without prior infection .
Although the clinical trials of COVID-19 vaccines excluded seropositive individuals from their efficacy calculations, there are emerging data that vaccination can also confer protection against reinfection. In a case-control study of SARS-CoV-2 reinfections in Kentucky, investigators found that individuals who had had natural infection in 2020 and who did not receive a vaccine had 2.34 times the odds of reinfection compared with individuals who had natural infection and then subsequently received a COVID-19 vaccine .
What Does 95% Effectiveness Mean

That is an extraordinarily high rate of effectiveness, and it means the COVID-19 vaccines work very well. By comparison, flu vaccines are about 40% effective, on average.
Heres where the number comes from: In the clinical trials, half the people got the coronavirus vaccine and half got the placebo. Researchers counted how many people got sick with COVID-19 after the vaccines reached their peak effectiveness. Among both groups in the Pfizer trial, 170 people total got COVID-19, but only eight of those received the vaccine. Thats about 5% of total cases. Thats where the 95% estimate comes from. Modernas numbers were similar.
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How Long Will Vaccine Immunity Last
Federal health authorities have not provided a definitive answer to this question.
But based on clinical trials, experts do know that vaccine-induced protection should last a minimum of about three months. That does not mean protective immunity will expire after 90 days that was simply the time frame participants were studied in the initial Pfizer, Moderna and Johnson & Johnson trials. As researchers continue to study the vaccines, that shelf life is expected to grow.
In the real world, the protection should last quite a bit longer, though the length of time still needs to be determined with further studies, experts said.
There are also certain factors that may influence how much protection they provide and for how long.
Chunhuei Chi, director of the Center for Global Health at Oregon State University, said immune responses vary from person to person. People who have a stronger immune response to a vaccine will produce more antibodies and memory cells and therefore have stronger immunity, he said. But there is not currently evidence to show that a stronger immune response will increase the duration of immunity.
And it does not mean people with a stronger immune response will have more severe side effects from the shots or vice versa, according to a recent survey by the British National Health System.
Even If Most Vaccinated Individuals Are Not Getting Really Sick Are There Other Benefits To Boosters
Reducing rates of infection should help break the cycle of viral transmission, which would ultimately result in fewer cases of severe COVID-19 and death. And according to Fyodor Kondrashov, an evolutionary geneticist at the Institute of Science and Technology Austria in Klosterneuburg, it should also help keep the emergence of vaccine-resistant variants at bay.
Things that are good from the epidemiological perspective, he says, are also good from the evolutionary perspective.
As Kondrashovs modelling work has shown, resistant viruses are most likely to emerge when transmission is not controlled. Getting more people vaccinated is the single most effective intervention to keep transmission rates low, but any bump in vaccine effectiveness can help as well.
So far, no human vaccine has been completely undermined by resistance in the way that many anti-infective drugs have, says Andrew Read, who studies the evolution of infectious diseases at Pennsylvania State University in University Park. Its eroded their benefits, he says, but in ways that have been fixable with tweaks in vaccine design.
Thats not to say it wont happen with COVID-19 vaccines. Were on new territory here, says Read. The Delta variant took the world by surprise. Evolution and our immunological responses could have more surprises in store.
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M Children Immunised In 2020
Countries immunised an additional 64 million children with Gavi support in 2020, often with more than one vaccine. Due to the impact of the COVID-19 pandemic, this represents a decrease from the 66 million children reached in 2019 but we exceeded our target of 300 million for the 20162020 period, helping countries immunise over 324 million unique children.
Vaccine Protection From Pfizer And Moderna May Last Years
The study “has found evidence that the immune response to such vaccines is both strong and potentially long-lasting,” reports the University. In fact, it may last “years.””Nearly four months after the first dose, people who received the Pfizer vaccine still had so-called germinal centers in their lymph nodes churning out immune cells directed against SARS-CoV-2, the virus that causes COVID-19. Germinal centers, which form as the result of natural infection or vaccination, are boot camps for immune cells, a place where inexperienced cells are trained to better recognize the enemy and weapons are sharpened. A better germinal center response may equal a better vaccine. Moreover, vaccination led to high levels of neutralizing antibodies effective against three variants of the virus, including the Beta variant from South Africa that has shown some resistance to vaccines. Vaccination induced stronger antibody responses in people who had recovered from SARS-CoV-2 infection compared to those who had never been infected.”
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Who Can Get The Polio Vaccine
In the UK, polio vaccinations are usually done as part of a baby or childs routine jabs, to protect from illness.
Babies at 8 weeks, 12 weeks and 16 weeks are vaccinated against polio as part of the 6-in-1 vaccine, which also protects from tetanus, whooping cough, diphtheria and hepatitis B.
From the age of 3 years, 4 months, a 4-in-1 booster jab covers polio, whooping cough, tetanus and diphtheria.
Last but not least is a 3-in-1 booster given to teenagers aged 14. This is often given in secondary schools, with parental consent, and is offered to homeschooled children.
However, anyone can get a polio vaccine at any time, and its usually free on the NHS.
The NHS website states: You can have a polio vaccination at any point if youve never had one before, even if youre not travelling to a country with a risk of getting polio.
You should also get vaccinated even if youve had polio before as it protects against different types of polio. Its usually free.
You can also pay privately for jabs that protect from polio, diphtheria and tetanus if needed for travel to a country where theres a higher risk of catching polio.
These are available from various providers, including for £32 at Superdrug. You get it two weeks before you need to travel.
> 117m Vaccinated Against Measles
Since 2007, countries have immunised over 117 million children with a first and/or second dose of measles or measles-rubella vaccine through Gavi-supported routine immunisation programmes. Activities were heavily impacted by the pandemic: in 2020, only 1 routine introduction and 5 campaigns took place, compared with 32 activities in 2019.
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If I Got The Johnson & Johnson Vaccine Can I Also Get Pfizer Or Moderna To Increase Protection
Mixing COVID-19 vaccine doses from different manufacturers is not recommended. There is very little data on safety and immune responses with mixed vaccines.
More than 13 million Americans have received the Johnson & Johnson vaccine. Johnson & Johnson has reported that its vaccine is effective against Delta. One recent study, which has not been peer-reviewed or published in a scientific journal, suggests that its vaccine is less effective against the Delta variant than other vaccines. This has prompted discussion over whether Johnson & Johnson recipients might also need a booster. But the first study to assess the vaccine against the Delta variant in the real world reported an efficacy of up to 71% against hospitalization and up to 95% against death.