Tag: vaccination

Can People Accurately Assess the Strength of Their Immune Systems?

Photo by Brittany Colette on Unsplash

People often say whether they feel like their immune system is ‘down’ – but could there be some truth to this? A recent study showed that when freshly vaccinated people self-assessed the strength of their immune response, their estimates correlated well to their measured antibody levels. They were even more accurate when their immune response was weak. The results were published in the journal Biological Psychology.

At the University of Konstanz, Stephanie psychologist Dimitroff researches the connection between our brain and our immune system. “Listen to your body,” she concludes from her study. “The field of medicine is moving towards greater patient orientation. Our findings support the idea that patients’ self-perceptions provide valuable clues about their state of health. Physicians should listen to them more.”

Communication between the immune and nervous systems

One part of our brain, the insula, receives information from the body and gives us a basic impression of its condition, which until now was assumed to be quite general in nature. Stephanie Dimitroff’s study now suggests that our brain can perceive the body’s condition more specifically than previously thought. Is it possible that our brain can assess the state of our immune system?

“Of course, our brain does not count antibodies. But our immune system is intrinsically connected to the central nervous system,” Dimitroff explains. “The immune system is regulated via this connection. And our brain also receives information from the immune system.”

This communication between the immune system and the central nervous system is key for our sense of well-being or illness. “It is important to know here: When we feel ill, for example, we have a cold, this feeling is caused quite significantly by the immune system’s communication with the central nervous system,” says Dimitroff. “The brain receives signals that something is wrong with the body and causes the feeling of illness as a result.”

The same flow of information between the immune and nervous systems can generally also take place when the body is not ill. This means it could be possible that this communication process gives us an impression of our immune system even when we are healthy. Stephanie Dimitroff’s study investigates whether this is actually the case.

Results of the study

The study looked at people who had received the COVID-19 vaccine. This group of participants was chosen because a particularly large number of people received the vaccine in the summer of 2021, when the study was conducted. 166 people between the ages of 18 and 59 participated in the study.

After vaccination, the participants in the study were able to assess surprisingly well how strongly their immune system was positioned to fight the respective illness. This was especially true for people who had developed only a few antibodies. In fact, 71% of participants who did not feel well protected after vaccination also had a below-average immune response. “Our most notable finding is that those who felt they had not produced high levels of antibodies after vaccination were often correct in their assessment.”

By contrast, participants who assessed their immune response as good were not always right. However, all of those who had a particularly strong immune response also reported feeling well protected.

Alternative interpretations

For Stephanie Dimitroff, however, it is still too early to draw any final conclusions. The psychologist is considering other possible causes, including the placebo effect. This is because communication between the brain and the immune system runs in both directions. The signals from our brain can therefore also influence our immune system. People who firmly believe in vaccination or are basically optimistic could thus actually develop a better immune defence (placebo effect) and also feel better protected. It is therefore possible that belief in the effectiveness of a vaccine is what improves its efficacy, and this could also explain the high accuracy of the self-assessments.

“Our results suggest that it is quite likely that people have a real ability to assess their own health. However, I cannot rule out that there is a combination of effects at play, including the placebo effect and/or feelings of optimism,” Dimitroff says. In her view, it would make sense to repeat the study in order to confirm the results and rule out alternative causes.

Source: University of Konstanz

Ways to Reduce Kids’ Needle-related Fear and Pain

Image of a syring for vaccination
Photo by Mika Baumeister on Unsplash

In the COVID era, when vaccinations are all the more important, new research published in the European Journal of Pain shows that children’s vaccination and needle fear can be reduced with a couple of different techniques used by nurses.

These techniques divide the children’s attention or redress their fears by framing the positive elements of their experience.

Working with children aged 8–12 years, the preliminary study found that two new nurse-led techniques show promise in reducing needle fear in primary-aged children:

  • Divided Attention – where a child’s attention and expectations are drawn away from the needle.
  • Positive Memory Reframing – where a child’s exaggerations about the distress and discomfort of needles are redressed through discussion about the positive elements of the experience so that the form more realistic memories of the event.

Dr Felicity Braithwaite, lead researcher of the study, said that helping children reduce fear and distress around vaccinations is a key area of research in the COVID era.

“For many children, undergoing a needle procedure can be painful and distressing,” Dr Braithwaite said.

“Negative experiences of vaccinations in childhood can often lead to medical avoidance and vaccine hesitancy into adulthood, which can have devastating consequences when it comes to outbreaks of preventable diseases.

“By investing more time into techniques to help children manage their fears about needles, we hope to change these outcomes and deliver better health outcomes for the next generation.”

The study involved 41 children and their parents, with participants randomised to one of four groups – usual care, divided attention, positive memory reframing, or a combination of the latter two interventions. Clinical outcomes were assessed at baseline, immediately post-vaccination and at two-weeks post-vaccination. 

The Divided Attention technique involved a one to two minute distraction game where a nurse tapped the child’s arm above and below the vaccination spot in a random order, with the child focussing their attention on guessing which spot was touched each time. This game takes advantage of the potential analgesic effects of distraction.

The Positive Memory Reframing technique involved talking to children about a past injection and emphasising positive aspects, such as how brave the child was and praising specific strategies they used to reduce their own distress, for example, deep breathing and looking away. The aim is to foster a sense of self-efficacy to help children better cope.

Both techniques were tested outside of clinical locations, such as in schools, to maximise their applicability in real-world settings.

Source: University of South Australia

Amid Measles Spike, WHO Warns of Outbreaks of Vaccine-preventable Diseases

Syringe injection into the upper arm
Image source: NCI on Unsplash

An increase in measles cases in January and February 2022 is a worrying sign of a heightened risk for the spread of vaccine-preventable diseases and could trigger larger outbreaks, particularly of measles affecting millions of children in 2022, warn WHO and UNICEF.

The agencies warn that pandemic-related disruptions, widening vaccine access inequality, and the under-resourcing of routine immunisation are leaving too many children open to measles and other vaccine-preventable diseases.

The risk for large outbreaks has increased as communities relax social distancing practices and other anti-COVID measures. Additionally, the displacement of millions of people due to conflicts and crises including in Ukraine, Ethiopia, Somalia and Afghanistan, is causing disruptions in immunisation services, a lack of clean water and sanitation, and overcrowding, all of which increase the risk of vaccine-preventable disease outbreaks.

Almost 17 338 measles cases were reported worldwide in January and February 2022, compared to 9665 during the first two months of 2021. Measles is highly contagious, so cases tend to show up quickly when vaccinations decline. The agencies are concerned that outbreaks of measles could also forewarn outbreaks of other diseases that do not spread as rapidly.

Apart from its direct, sometimes lethal, effect on the body, the measles virus also weakens the immune system rendering a child more vulnerable for months after to other infectious diseases like pneumonia and diarrhoea.  Most cases occur in settings that have faced social and economic hardships due to COVID, conflict or other crises, and have chronically weak health system infrastructure and insecurity.

“Measles is more than a dangerous and potentially deadly disease. It is also an early indication that there are gaps in our global immunization coverage, gaps vulnerable children cannot afford,” said Catherine Russell, UNICEF Executive Director. “It is encouraging that people in many communities are beginning to feel protected enough from COVID to return to more social activities. But doing so in places where children are not receiving routine vaccination creates the perfect storm for the spread of a disease like measles.”  

In 2020, 23 million children missed out on basic childhood vaccines through routine health services, the highest number since 2009 and 3.7 million more than in 2019.

Top 5 countries with reported measles cases in the last 12 months, until April 2022 1

CountryReported Measles casesRate per million casesFirst dose measles coverage (%), 20192First dose measles coverage (%), 20203
Somalia90685544646
Yemen36291196768
Afghanistan3628916466
Nigeria12 341585454
Ethiopia3039266058

As of April 2022, the agencies report 21 large and disruptive measles outbreaks around the world in the last 12 months. Most of the measles cases were reported in Africa and the East Mediterranean region. The figures are likely higher as the pandemic has disrupted surveillance systems globally, with potential underreporting.

Countries with the largest measles outbreaks since the past year include Somalia, Yemen, Nigeria, Afghanistan and Ethiopia. Insufficient measles vaccine coverage is the major reason for outbreaks, wherever they occur.

“The COVID pandemic has interrupted immunisation services, health systems have been overwhelmed, and we are now seeing a resurgence of deadly diseases including measles. For many other diseases, the impact of these disruptions to immunisation services will be felt for decades to come,” said Dr Tedros Adhanom Ghebreyesus, Director-General of the World Health Organization. “Now is the moment to get essential immunisation back on track and launch catch-up campaigns so that everybody can have access to these life-saving vaccines.”

As of 1 April 2022, 57 vaccine-preventable disease campaigns in 43 countries that were scheduled to take place since the start of the pandemic are still postponed, impacting 203 million people, most of whom are children. Of these, 19 are measles campaigns, which put 73 million children at risk of measles due to missed vaccinations. In Ukraine, the measles catch-up campaign of 2019 was interrupted due to the COVID pandemic and thereafter due to the war. Routine and catch-up campaigns are needed wherever access is possible to help make sure there are not repeated outbreaks as in 2017–2019, when there were over 115 000 cases of measles and 41 deaths in the country – this was the highest incidence in Europe.

Coverage at or above 95% with 2 doses of the safe and effective measles vaccine can protect children against measles. However, COVID pandemic related disruptions have delayed the introduction of the second dose of the measles vaccine in many countries.

Source: World Health Organization

Differences in Natural and Vaccine-induced COVID Immunity Revealed

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A new study recently published in Nature has found that immune protection resulting from COVID protection creates lasting effects in memory B cells.

Unlike circulating antibodies, which peak soon after vaccination or infection only to fade a few months later, memory B cells can remain to ward off severe disease for decades. They also evolve over time, learning to produce successively more potent ‘memory antibodies’ that are more effective at neutralising the virus and with better adaptation to variants.

Though vaccination instils higher levels of circulating antibodies than natural infection, the study suggests that not all memory B cells are created equal. While vaccination gives rise to memory B cells that evolve over a few weeks, natural infection births memory B cells that continue to evolve over several months, producing highly potent antibodies adept at eliminating even viral variants.

Though the findings suggest an advantage from natural infection over vaccination, this does not outweigh the dangers of illness and death from COVID, the researchers warn.

“While a natural infection may induce maturation of antibodies with broader activity than a vaccine does – a natural infection can also kill you,” explained Professor Michel C. Nussenzweig, head of Rockefeller’s Laboratory of Molecular Immunology. “A vaccine won’t do that and, in fact, protects against the risk of serious illness or death from infection.”

When any virus enters the body, immune cells immediately release circulating antibodies, which decay at variable rates depending on the vaccine or infection. They may confer protection for months or years but then dwindle in number, allowing possible reinfection.

Long term protection is provided by memory B cells that produce memory antibodies. Studies suggest that memory B cells for smallpox last at least 60 years after vaccination; those for Spanish flu, nearly a century. And while memory B cells don’t necessarily block reinfection, they can prevent severe disease.

Recent studies have suggested that within five months of receiving a vaccine or recovering from a natural infection, some no longer retain sufficient circulating antibodies to keep the novel coronavirus at bay, but memory B cells remain vigilant. Until now, however, scientists did not know whether the vaccines could be expected to provide the sort of robust memory B cell response seen after natural infection.

Prof Nussenzweig and colleagues resolved to tease out any differences in memory B cell evolution by comparing blood samples from convalescent COVID patients to those from never-infected mRNA-vaccinated individuals.

Vaccination and natural infection elicited similar numbers of memory B cells, which rapidly evolved between the first and second dose of the Pfizer and Moderna vaccines, producing increasingly potent memory antibodies. But after two months, progress stalled. The memory B cells were present in large numbers and expressed potent antibodies, but the antibodies were not getting any stronger. Also, although some of these antibodies were able to neutralize Delta and other variants, there was no overall improvement in breadth.

The researchers found that in convalescent patients, however, memory B cells continued to evolve and improve up to one year after infection. With every memory B cell update, more potent and more broadly neutralising memory antibodies were coming out.

There are several potential reasons that memory B cells produced by natural infection might be expected to outperform those produced by mRNA vaccines, the researchers said.

It is possible that the body responds differently to viruses that enter through the respiratory tract than those that are injected. Or perhaps an intact virus goads the immune system in a way the vaccines’ spike protein antigens simply cannot. It may also be possible that the virus persists in the naturally infected for weeks, giving the body more time to mount a robust response. The vaccine, on the other hand, is flushed out of the body mere days after triggering the desired immune response.

Memory B cells appear to undergo limited bouts of evolution in response to mRNA vaccines, a finding which may have significant implications for booster shots. A booster with the current mRNA vaccine would likely stimulate memory cells to produce antibodies strongly protective against the original virus and somewhat less so against the variants, Prof Nussenzweig said.

“When to administer the booster depends on the object of boosting,” he said. “If the goal is to prevent infection, then boosting will need to be done after 6 to 18 months depending on the immune status of the individual. If the goal is to prevent serious disease, boosting may not be necessary for years.”

Source: Rockefeller University

Attenuated Virus Confers Broader Flu Protection

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A mouse study using both attenuated and inactivated forms of influenza has helped explain why people vaccinated with the inactivated virus still occasionally end up contracting the illness. The finding should help researchers develop vaccines that offer broad protection against viruses.

Influenza is a major global health burden, with the World Health Organization estimating that it causes one billion cases annually. Each year, vaccines are developed that offer some protection against infection. But the influenza virus is a moving target that is constantly mutating, and so vaccines can lose their effectiveness as a season progresses.

Influenza vaccines commonly come in two forms: inactivated vaccines (including component vaccines) and live attenuated vaccines. Live vaccines confer broader protection against variants than inactivated vaccines, but side effects such as fevers and headaches are more common. A result they have yet to be approved in some countries. Live vaccines induce the production of broadly reactive antibodies, but until now, scientists didn’t know why.

In a recent study, Masato Kubo of the RIKEN Center for Integrative Medical Sciences and his co-workers have discovered two processes that live vaccines induce in mice that together account for their broader protection.

They found that, like the virus itself, the live vaccine virus causes the virus to replicate deep in the lungs, which in turn induces a structural change in the virus haemagglutinin, a mushroom-shaped protein on the surface of the virus involved in infecting cells. This structural change exposes previously hidden regions of antigens that the immune system can recognise.

Next, germinal cells are activated by interleukin 4 (IL-4), a cytokine heavily involved in regulating antibody production. IL-4 is derived from special T cells known as follicular helper T cells. This activation causes a minor population of B cells to proliferate and it is these B cells that are responsible for generating broadly protective antibodies.

The role of IL-4 in inducing the broad immune response came as a surprise. “Until now there had been no direct evidence to show the importance of IL-4,” says Kubo. “That was one of the surprises of this study for me.”

“We believe both processes are needed for generating broadly active antibodies: viral duplication in the lungs and expansion of the minor population of B cells,” says Kubo. “These two processes mostly likely occur when a person is infected by the influenza virus itself.”

The team now plans to see if there are similar mechanisms for other viruses such as SARS-CoV-2.

Source: RIKEN

The Nagging Pain of Vaccination Shoulder Injuries

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Shoulder injury related to vaccine administration (SIRVA) has been documented long before COVID, and most commonly reported after influenza vaccination. The cause is often due to poor administration. 

However, the medical community cautions that currently it’s more of a medicolegal determination rather than a distinct diagnosis. The condition is also plagued by the lack of a solid evidence base, and causality is difficult to pin down.

However, most physicians that MedPage Today interviewed put shoulder injury down to improper injection technique, and that these problems should be taken seriously and treated appropriately. One recent overview noted that SIRVA is a “rare yet increasingly recognised complication of immunisation.”

“We’re certainly not seeing a pandemic of SIRVA” from COVID vaccines, said Dr DJ Kennedy, chair of physical medicine & rehabilitation at Vanderbilt University Medical Center. “It’s really rare and the literature to date is mostly case reports. But I do think it’s possible, absolutely” for vaccine-related shoulder injury to occur.

Dr Laura Keeling, orthopedic surgeon at MedStar Georgetown University Hospital, told MedPage Today that part of the reason SIRVA remains in the medicolegal realm is that it’s “more of a constellation of symptoms and findings” as opposed to a specific diagnosis.

Symptoms can vary depending on where the stray shot landed, resulting in various manifestations such as bursitis, tendonitis, or adhesive capsulitis (aka ‘frozen shoulder’).

Generally, it’s characterised as a “constellation of shoulder pain and reduced range of motion that occurs within 48 hours of vaccination and does not resolve within 1 week,” according to a recent paper co-authored by Dr Keeling. It’s also different from typical post-injection soreness, as the pain is more severe and it can impact mobility and function.

Generally, treatments include anti-inflammatory drugs, corticosteroid injections, and physical therapy. Occasionally surgery is necessary to treat an underlying pathology such as an exacerbated rotator cuff injury. Patients with SIRVA often land in their GP’s office first, and then may be referred to a specialist such as a physiatrist or an orthopedic surgeon.

“It’s the patients who have persistent symptoms who are referred to orthopedic surgeons,” Dr Keeling said. “If physical therapy and injection don’t work, then primary care refers to us.”

Physical medicine & rehabilitation physicians, or physiatrists, also play a large role in treating SIRVA.

“We treat based on a full evaluation including history and physical findings, and imaging if needed,” Dr Kennedy said. “Then we develop a comprehensive rehabilitation plan … that usually involves doing range of motion and strengthening exercises on a daily basis.”

Scott Noren, DDS, an oral surgeon in Ithaca, New York, said after his second COVID shot in early February, he developed shoulder pain: “It went in pretty deep and pretty high,” he told MedPage Today.

An MRI revealed fluid collecting in his joint, as well as adhesive capsulitis, he said. Physical therapy helped improve his range of motion to an extent, but he has lingering pain. It’s difficult to take x-rays and do long procedures as an oral surgeon: “I have pretty good pain even with just normal function now,” he said.

Source: MedPage Today

Minimal COVID Breakthrough in Vaccinated Healthcare Workers

Photo by Sammy Williams on Unsplash
Photo by Sammy Williams on Unsplash

Results from a study of cases at Israel’s largest medical centre have shown that breakthrough COVID infection appears to be rare in vaccinated healthcare workers, though they still pose a further infection hazard. Breakthrough infections were correlated with neutralising antibody titres in the early days of infection, and were mild or asymptomatic.

The findings were published in the New England Journal of Medicine. Testing for symptomatic COVID as well as those who had been exposed to an infected person, out of 1497 healthcare workers, the researchers found 39 testing positive in PCR tests. The researchers also measured neutralising antibody titres of uninfected controls. Breakthrough infections were defined as testing positive for SARS-CoV-2 11 days after the second immunisation dose.

Of the 39 cases, 27 occurred in workers tested solely because of exposure to an infected person, 26 (67% of all cases) had mild symptoms at some stage, and none needed hospitalisation. The remaining 13 workers (33%) were asymptomatic. The researchers found that 85% of the 33 infections tested for variants of concern were caused by the Alpha variant.

Symptoms reported included upper respiratory congestion (36% of all cases), myalgia (28%) and loss of smell or taste (28%); fever or rigors were reported in 21%. On follow-up questioning, 31% reported having residual symptoms 14 days after diagnosis. Six weeks after their diagnosis, 19% reported having ‘long COVID’ symptoms. Nine workers (23%) took a leave of absence from work beyond the 10 days of required quarantine.

They discovered that neutralising antibody titres were lower than uninfected controls during the “peri-infection period”.

“Most important, we found that low titres of neutralising antibody and S-specific IgG antibody may serve as markers of breakthrough infection,” they said.

Most of the cases however had N gene Ct values, suggesting they had been infectious at some point, which likely would have gone unnoticed save for exposure screening, which means the vaccine protected them against symptomatic disease, but not infection.

“However, no secondary infections were traced back to any of the breakthrough cases, which supports the inference that these workers were less contagious than unvaccinated persons,” the researchers noted.

The study was limited, the researchers acknowledged, due to a small number of cases, the possibility of asymptomatic cases being missed, and the lack of generalisability from a younger, healthy population to the general populace.

The researchers concluded that in their study, they “found that although the BNT162b2 vaccine is extremely effective, rare breakthrough infections carry an infectious potential and create a special challenge, since such infections are often asymptomatic and may pose a risk to vulnerable populations.”

Journal information: Bergwerk M., et al. Covid-19 breakthrough infections in vaccinated health care workers, New England Journal of Medicine, 2021; DOI: 10.1056/NEJMoa2109072.

India Tests Out Drones for Medical Deliveries

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An aviation firm has carried out the first tests in India of drone deliveries at long ranges, in a step towards one day delivering medicines as well as COVID vaccines to remote areas.

India, with a population of 1.3 billion people spread across some 3.2 million square kilometres is the world’s seventh-largest country by land mass. Experts say that widespread use of drones could be a game-changer for medical services in the South Asian nation’s hard-to-reach rural areas with often poor roads and lack of healthcare infrastructure.

Drones are a cost-effective alternative to road transport in difficult terrains. They can be used in the transport of blood from the blood bank to the place of surgery and that of specimens from hard-to-reach areas to the labs in nearby towns. They can deliver essential medicines like anti-venom for snake bite and dog bite and prevent deaths.

Throttle Aerospace Systems is among 20 organisations granted permits by the government since May to conduct experimental flights beyond the current limit of 450 metres.

Two drones were tested in the southern state of Karnataka: one that can carry up to one kilogramme for 20 kilometres for nearly an hour, and another that can lift two kilogrammes for 15 kilometres.

“Medicines was the payload here and… 2.5 kilometres were covered in seven minutes and it delivered the medicines at the designated point and the drone returned,” Throttle’s co-founder, Sebastian Anto, told AFP at the test site.

This month the Indian government also invited bids from drone operators to help set up a pilot project for the delivering of medical supplies as it seeks to bolster its flagging COVID vaccination drive.

Samiran Panda,  epidemiology chief of the Indian Council of Medical Research, told The Hindu daily newspaper that the technology could help innoculate priority groups in hard-to-reach places.

“We need smart vaccination instead of mass vaccination to stem an epidemic,” Panda told the newspaper last week.

However, India lags behind many other nations when it comes to drones both in terms of their uses and the regulatory framework.Under current regulations, they have to be flown in full view, or within 450 metres, of their operators on the ground.

In Germany, it is reported that researchers are testing drone prototypes that can track down disaster victims by their screams. In Australia, drones using artificial intelligence algorithms are being used to spot crocodiles and count koalas in rugged terrain.

“Drone technology would have a huge impact in those areas where emergency medicines and vaccines could be supplied,” co-founder of lobby group the Drone Federation of India, Vipul Singh, told AFP.

“Where it takes a few hours to travel 20-30 kilometres by road, whereas a drone can actually travel that distance in 10 to 15 minutes,” said Singh, also the co-founder of Bangalore-based Aarav Unmanned Systems.

Source: Medical Xpress

The Second Vaccine Dose Can Hit Hard

The scuttlebut among healthcare workers is that the second dose of a COVID vaccine hits much harder than the first – unless you’ve had COVID, in which case the first is equally as bad.

TJ Maltese, DO, a neurologist in private practice on Long Island in New York state, was fine with the first dose of the Moderna vaccine but was flattened by the second one.

Dr Maltese got his second jab on a Friday at 4:30 pm. Within two hours his arm was sore. Overnight, he developed flu-like symptoms, and on Saturday experienced chills and body aches, with a lingering fever. He could have pushed through if he’d had to work, he said, but he rode out his symptoms on his couch with the help of the occasional painkiller.

By 9 pm on Saturday evening, Dr Maltese started to feel better, getting a good night’s sleep and on Sunday was fine again.

“I know plenty of people with minimal symptoms after the second dose, so it’s not definite you’ll feel side effects,” he wrote in a Facebook post. “But be prepared for the possibility.”

Immunology and the phase III clinical trial data from the vaccine backs up the view that the second dose is worse, and some hospitals have even altered their scheduling to allow time for recuperation after the second dose. Adverse reactions to the BCG vaccine in Brazilian school children, for example, have been reported to be common with the second dose, though still rare.  

Immunologists and infectious disease experts interviewed by MedPage Today and who shared their second-dose experiences said it’s not unexpected that second-dose reactions are more intense than the first. Typical reactions to the COVID vaccines include fever, headache and fatigue as the immune system responds to a vaccine’s antigens.

“The first time the immune system comes into contact with something, it’s getting primed,” said Purvi Parikh, MD, an immunologist at NYU Langone Health in New York City. “That goes for everything, from vaccines to allergies. It’s rare on the first time to have a strong reaction. After that, the immune system recognizes it, so you have a much stronger reaction.”

“We saw it in the trials, so it’s really not surprising,” Parikh added. “Now we’re seeing it in real time as the vaccines are being rolled out.”

More adverse effects were reported after the second dose in both Pfizer’s and Moderna’s phase III trial data. For Moderna, the rates were 54.9% versus 42.2% for placebo after the first dose and 79.4% versus 36.5% for placebo after the second dose.

Stanley Weiss, MD, an infectious disease specialist and epidemiologist at Rutgers New Jersey Medical School, told MedPage Today that because his institution served as a Moderna trial site, the primary investigator was able to give an early update on what to expect following vaccination.

“They said there was a very high rate of fatigue after the second dose, so we encouraged administrators … to figure that many healthcare workers getting the vaccine might not be well enough to work the day after the second dose,” Dr Weiss said.

Drs Weiss and Parikh both experienced a stronger response to the second COVID dose. 

Zubin Damania, MD, aka ZDoggMD, said he was knocked out by the second dose of Moderna vaccine, joking on his show that, “I couldn’t sleep, I had a fever, rigors, body aches, a headache — full-on man-flu.”

Paul Offit, MD, said that he also experienced fever and fatigue after taking the second dose of the Pfizer vaccine.

“That reaction is less common in people over 65, and I’m over 65, so I’m thinking I’m not going to suffer that, but I did,” Dr Offit said.

Older people are not expected to have as intense a reaction due to their weaker immune systems. According to Dr Parikh, “The idea is that their immune system is not as robust as a young person’s.”
The same immunological underpinnings of why reactions to the second dose are worse also apply to those who’ve had COVID.
Victoria Arthur, MD, of Lexington Pediatrics in Massachusetts, had suspected she had contracted COVID in March 2020 but could not prove it. When she received the Moderna vaccine, she felt much worse than her colleagues.

“How I felt was how everyone else was describing their second vaccine,” Dr Arthur told MedPage Today. Within three hours of her jab, she was suffering from a headache, neck pain, and cognitive fog. She awoke at 3am with nausea and stomach cramps, and spent the whole of the next day in bed. 

“I’m always grateful when I have a reaction, that means the body is doing its thing,” she said. “I’m very fortunate to have been given the vaccine, so any side effect is worth it.”

In spite of the side effects, these health care professionals all expressed gratitude at having been vaccinated.

Dr Weiss said that people shouldn’t be discouraged by the side effects from the second dose and not get vaccinated: “The benefits greatly overwhelm the risk of side effects. It’s not a reason to delay.”

Source: MedPage Today

Pfizer Vaccine 90% Effective After a Single Dose

A study from the University of East Anglia (UEA) reported that the Pfizer vaccine provides “very high” protection after a single dose.

The researchers drew on Israeli data, where the vaccine had been widely administered, and found that the vaccine was 90% effective at 21 days after the initial dose. This supports the plan that the UK and other nations have of delaying a second dose to achieve maximum coverage. However, they also noted that infection rates increased eight days after the first dose, which they attribute to people becoming less cautious as a result of the vaccination. The study is available on the medRxiv preprint server, and has not been peer reviewed, as it is a rapid response to the ongoing COVID pandemic.

Lead researcher and COVID expert Prof Paul Hunter, from UEA’s Norwich Medical School, said: “A second dose of the Pfizer vaccine would normally be given 21 days or more after the first to top up and lengthen the effect of the first dose.

“But here in the UK, the decision was made to delay the timing of the second injection until 12 weeks after the first.

“The logic behind this is to protect more people sooner and so reduce the total number of severe infections, hospitalisations, and deaths.

“But this decision caused criticism from some quarters due in part to a belief that a single injection may not give adequate immunity.”

Prof Hunter explains the motivation for the study was previous flawed research on the Pfizer vaccine, also using Israeli data. But the study did not consider effectiveness past day 18.

The researchers observed that case incidence rose up til day eight by which time it had doubled, then fell. Prof Hunter said: “We found that the vaccine effectiveness was still pretty much zero until about 14 days after people were vaccinated. But then after day 14 immunity rose gradually day by day to about 90 percent at day 21 and then didn’t improve any further. All the observed improvement was before any second injection.

“This shows that a single dose of vaccine is highly protective, although it can take up to 21 days to achieve this.”

Although the vaccine’s effectiveness beyond this is not known, it still supports the UK’s decision to space out vaccine doses, Prof Hunter concluded.

Source: Medical Xpress

Journal information: “Estimating the effectiveness of the Pfizer COVID-19 BNT162b2 vaccine after a single dose. A reanalysis of a study of ‘real-world’ vaccination outcomes from Israel” is published on the medRxiv pre-print server: www.medrxiv.org/content/10.110 … 021.02.01.21250957v1