Category: Vaccines

Categories : VaccinesTags :

Why Most People in South Africa Can’t Get the Shingles Vaccine

On By ModernMedia
There are two vaccines against shingles – an often painful and debilitating condition caused by the same virus that causes chickenpox – but neither are available in South Africa. Photo by Mika Baumeister on Unsplash

By Catherine Tomlinson

The only shingles vaccine on the market in South Africa was discontinued last year. A newer and better vaccine is being used in some other countries, but has not yet been registered in South Africa, though it can be obtained by those with money who are willing to jump through some hoops.

Shingles is a common and painful condition that mostly affects the elderly and people with weakened immune systems. It generally appears with a telltale red rash and cluster of red blisters on one side of one’s body, often in a band-like pattern.

“Shingles is pretty awful to get – it’s extremely painful, and some people can get strokes, vision loss, deafness and other horrible manifestations as complications,” said infectious disease specialist Professor Jeremy Nel. “Shingles really is something to avoid, if at all possible,” he added.

One way to prevent the viral infection is by getting vaccinated against it. But while two vaccines against shingles have been developed and broadly used in the developed world, neither of these are currently available in South Africa.

Two vaccines

Zostavax, from the pharmaceutical company MSD, was the first vaccine introduced to prevent shingles. It was approved for use in the United States in 2006 and in South Africa in 2011. It is 51% effective against shingles in adults over 60.

A more effective vaccine, Shingrix, that is over 90% effective in preventing shingles was introduced by GlaxoSmithKline (GSK) in the United States in 2016. It is not yet authorised for use in South Africa, but GSK has submitted paperwork for approval with the South African Health Products Regulatory Authority (SAHPRA), said the company spokesperson, Kamil Saytkulov.

The superior protection offered by Shingrix compared to Zostavax quickly made it the dominant shingles vaccine on the market. As a result, MSD discontinued the production and marketing of Zostavax. MSD spokesperson Cheryl Reddy said Zostavax was discontinued globally in March 2024. Before then, the vaccine was sold in South Africa’s private healthcare system for about R2 300, but it was never widely available in government clinics or hospitals.

No registered and available vaccine

Since Zostavax has been discontinued and Shingrix remains unregistered, the only way to access a vaccine against shingles in South Africa is by going through the onerous process of applying to SAHPRA for a Section 21 authorisation – a legal mechanism that allows the importation of unregistered medicines when there is an unmet medical need.

“Access will only be available to those who are able to get Section 21 approval” and “this is a costly and time-consuming process, requiring motivation by a doctor,” said Dr Leon Geffen, director of the Samson Institute For Ageing Research.

The cost of the two-dose Shingrix vaccine imported through Section 21 authorisations is currently around R15 600, said Dr Albie de Frey, CEO of the Travel Doctor Corporation.

People who do go through the effort of getting Section 21 authorisation typically have to pay this price out of their own pockets.

“Shingrix is not covered [by Discovery Health] as it is unregistered in South Africa and is therefore considered to be a General Scheme Exclusion,” Dr Noluthando Nematswerani, Chief Clinical Officer at Discovery Health, told Spotlight.

The Department of Health did not respond to queries regarding whether Section 21 processes are being pursued for priority patients in the public sector or whether there has been any engagement with GSK regarding the price of this product.

People who receive organ transplants, for example, should be prioritised to receive the shingles vaccine as the medications they are given to suppress their immune system puts them at a high risk of developing shingles.

Why is the price of Shingrix so high?

Unlike South Africa, where companies must sell pharmaceutical products at a single, transparent price in the private sector, the United States has no such requirement. Even so, the US Centers for Disease Control and Prevention (CDC) pays $250 or R4600 for the two-dose Shingrix vaccine through CDC contracts. This is less than a third of the price charged when Shingrix is imported into South Africa.

Equity Pharmaceuticals, based in Centurion in Gauteng, is importing GSK’s Shingrix for patients that receive Section 21 authorisations to use the unregistered vaccine. It is unclear what price Equity Pharmaceuticals is paying GSK for Shingrix to be imported into South Africa under Section 21 approvals, or what Equity Pharmaceuticals’ mark up on the medicine is.

When asked about the price of Shingrix in South Africa, Saytkulov told Spotlight: “Equity Pharmaceuticals is not affiliated with GSK nor is it a business partner or agent of GSK. Therefore, we cannot provide any comments with regards to pricing of a non-licensed product, which has been authorized for importation through Section 21.”

Equity Pharmaceuticals also said it was difficult to comment on the price. “The price of a Section 21 product depends on a number of fair considerations, including the forex rate, the quantity, transportation requirements, and the country of importation. Once the price and lead time are defined for an order, the information is shared with the healthcare provider to discuss with their patient and the medical aid,” the company’s spokesperson Carel Bouwer told Spotlight

Nematswerani pointed out that “Section 21 pricing is not regulated” and that price can change due to many factors including supplier costs, product availability, and inflation.

What causes shingles?

Shingles is caused by the same highly infectious virus that causes chickenpox. Most people are infected with the varicella-zoster virus (VZV) during childhood. Chickenpox occurs when a person is first infected by VZV. When a person recovers from chickenpox, the VZV virus remains dormant in their body but can reactivate later in life as one’s immune system weakens. This secondary infection that occurs, typically in old age when the dormant virus reactivates, is called shingles.

People who were naturally infected with chickenpox, as well as those vaccinated against chickenpox with a vaccine containing a weakened form of the VZV virus, can get shingles later in life.

But, people who were vaccinated against chickenpox have a significantly lower risk of developing shingles later in life compared to those who naturally contracted chickenpox, according to the World Health Organization (WHO).

The chickenpox vaccine is available in South Africa’s private sector but is not provided in the public sector as part of government’s expanded programme on immunisation. Chickenpox is usually mild in most children, but those with weakened immune systems at risk of severe or complicated chickenpox should be vaccinated against it, said Professor James Nuttall, a paediatric infectious diseases sub-specialist at the Red Cross War Memorial Children’s Hospital and the University of Cape Town.

Who should be vaccinated against shingles?

South Africa does not have guidelines regarding who should receive the shingles vaccine and when they should receive it. The US CDC recommends that all adults over 50 receive the two-dose Shingrix vaccine. They also recommend that people whose immune systems can’t defend their body as effectively as it should, like those living with HIV, should get the vaccine starting from age 19.

While Shingrix works better than Zostavax at preventing shingles, it has other advantages that make it a safer and better option for people with weak immune systems.

The Zostavax vaccine contains a weakened live form of the VZV virus and thus poses a risk of complications in people with severely weakened immune systems. “In the profoundly immunosuppressed, the immune system might not control the replication of this weakened virus,” explained Nel. The Shingrix vaccine does not contain any live virus and therefore does not present this risk.

In March 2025, the WHO recommended that countries where shingles is an important public health problem consider the two-dose shingles vaccine for older adults and people with chronic conditions. “[T]he vaccine is highly effective and licensed for adults aged 50 years and older, even if they’ve had shingles before,” according to the WHO. It advised countries to look at how much the vaccine costs compared to the benefits before deciding to use it.

The cost of not vaccinating against shingles

The cost of not vaccinating against shingles is high for people who develop the condition, as well as the health system.

“[T]he risk of getting shingles in your lifetime is about 20 to 30%…by the age of 80 years, the prevalence is almost 50%,” said Geffen. “Shingles is often a painful debilitating condition, with significant morbidity. It can result in chronic debilitating pain which affects sleep, mood and overall function,” he added.

Beyond preventing shingles and its complications, new evidence suggests that getting the shingles vaccine may also reduce one’s risk of developing dementia and heart disease.

In April, a large Welsh study published in Nature reported that people who got the Zostavax vaccine against shingles were 20% less likely to develop dementia seven years after receiving the vaccine compared to those who were not vaccinated.

In May, a South Korean study published in the European Heart Journal reported that people vaccinated against shingles had a 23% lower risk of cardiovascular events, such as strokes or heart disease for up to eight years after vaccination.

Republished from Spotlight under a Creative Commons licence.

Read the original article.

Categories : VaccinesTags :

Amid Surge in Cases, UK’s NHS to Offer Gonorrhoea Vaccine

On By ModernMedia

Neisseria gonorrhoeae Bacteria Scanning electron micrograph of Neisseria gonorrhoeae bacteria, which causes gonorrhoea. Captured by the Research Technologies Branch (RTB) at the NIAID Rocky Mountain Laboratories (RML) in Hamilton, Montana. Credit: NIAID. Photo by National Institute of Allergy and Infectious Diseases on Unsplash

In the midst of a record high in gonorrhoea cases, the NHS is to offer a gonorrhoea vaccine to gay and bisexual men with a history of multiple partners or a sexually transmitted infection (STI), the BBC reports. The gonorrhoea vaccination, which is actually a repurposed meningococcal vaccine, is estimated only to be 30–40% effective. Research shows, however, that this will be sufficient to reduce cases and their attendant costs to the NHS.

Gonorrhoea is caused by the bacterium Neisseria gonorrhoeae and is typically transmitted by having intercourse without a condom. It can cause pain, unusual discharge, genital inflammation and infertility. Evidence has shown that the MeNZB and four-component serogroup B meningococcal (4CMenB) vaccines, designed against Neisseria meningitidis, can also offer protection against gonorrhoea.

In 2023, there were more than 85 000 cases – the highest since records began in 1918. A study published in The Lancet estimates that gonorrhoea vaccination would prevent 100 000 cases, saving the NHS £7.9 million over the next decade.

While gonorrhoea is treatable with antibiotics, resistance is growing and there is concern that it may eventually become untreatable. According to The Guardian, some cases are now “extensively drug resistant” (XDR) – not responsive to ceftriaxone or the second line of treatment. There were 17 cases of ceftriaxone-resistant gonorrhoea between January 2024 and March 2025, the UK Health Security Agency (UKHSA) reported.

Over the same period, nine XDR cases were reported, while between 2022 and 2023, there were only five.

The people most affected by gonorrhoea in the UK are the 16 to 25 age group, gay and bisexual men, and those of black and Caribbean ancestry. The study’s scenario for vaccinating at-risk populations included those who had more than five sexual partners per year or who had a positive gonorrhoea test.

The vaccine, costing about £8 per dose, is cost-effective when administered to this at-risk group of men, rather than adolescents. Despite this, clinicians will be able to offer the vaccine to anyone who, in their judgment, would benefit from it. Other vaccines such as for mpox – another STI with high transmission between gay and bisexual men – and hepatitis will also be offered.

Categories : VaccinesTags :

Needle-free Influenza Vaccines with Broad Protection

On By ModernMedia
Photo by CDC on Unsplash

A research team led by the University of Hong Kong have achieved an award-winning breakthrough in developing broadly protective, live-attenuated influenza vaccines (LAIV). These innovative LAIV platforms offer the potential to develop universal influenza vaccines that induce a more robust immune response against various virus subtypes, including both human and avian strains. Since they induce mucosal immune responses, they can also be administered nasally.

Current seasonal influenza vaccines protect primarily against three selected strains and require annual updates. Their efficacy can significantly decline if the circulating viruses do not match the strains chosen each year for each hemisphere. Moreover, these vaccines fail to guard against human infections caused by animal influenza viruses, such as avian strains, which pose a potential global pandemic threat. The World Health Organization (WHO) has underscored the urgent need for a new generation of universal influenza vaccines.

The research team developed two innovative approaches to create next-generation LAIVs. The first strategy involved engineering a human influenza virus with then gene for α-Gal, which is already targeted by human antibodies. Vaccine-infected cells then express α-Gal on their surfaces and boost vaccine-induced immune responses, including antibody-mediated cytotoxicity, opsonisation and phagocytosis.

The research data showed that the vaccine is attenuated in mouse models. Vaccinated mice showed strong innate and adaptive immune responses, including antibody and T-cell responses. These immune responses conferred broad protection against various influenza A virus subtypes, including human H1N1 and H3N2, and avian H5N1 strains.

The second approach to developing next-generation LAIVs involved introducing hundreds of silent mutations to a human influenza virus, shifting its codon usage from that of a human influenza virus to that of an avian influenza virus-like pattern. This shift resulted in the attenuation of the virus in mammalian cells, making it safe for use as an LAIV.

Additionally, the mutant virus replicated perfectly in chicken eggs, which is crucial for current effective vaccine manufacturing processes. With this approach, the viral protein expression of the LAIV remained identical to the original wild-type virus, providing a robust immune response against the viruses. The research team successfully generated several attenuated viruses with different human influenza virus backbones, including H1N1 and H3N2.

The development of these two award-winning LAIVs represents a significant advancement in the quest for broadly protective and efficient influenza vaccines. This new generation of LAIVs can both protect humans from seasonal influenza viruses and address the threat posed by emerging viruses, like avian influenza viruses.

“The advantages of LAIVs lie in their intranasal administration, which has been shown to induce mucosal immune responses along the respiratory tract, providing additional protection against infection,” highlighted Professor Leo Poon Lit-man, Chair Professor of Public Health Virology and Head of the Division of Public Health Laboratory Sciences, School of Public Health, HKUMed. “This needle-free delivery method alleviates the fear of vaccination, particularly in young children, so it will help mitigate vaccine hesitancy.”

Source: The University of Hong Kong

Categories : Cardiovascular Disease VaccinesTags :

Shingles Vaccine Reduces Heart Disease Risk for up to Eight Years

On By ModernMedia
Photo by Gustavo Fring on Pexels

People who are given a vaccine for shingles have a 23% lower risk of cardiovascular events, including stroke, heart failure, and coronary heart disease, according to a study of more than a million people published in the European Heart Journal.

The protective effect of the vaccine lasts for up to eight years and is particularly pronounced for men, people under the age of 60 and those with unhealthy lifestyles, such as smoking, drinking alcohol and being inactive.

The study was led by Professor Dong Keon Yon from the Kyung Hee University College of Medicine, Seoul, South Korea. He said: “Shingles causes a painful rash and can lead to serious complications, especially in older adults and those with weak immune systems. Previous research shows that, without vaccination, about 30% of people may develop shingles in their lifetime.

“In addition to the rash, shingles has been linked to a higher risk of heart problems, so we wanted to find out if getting vaccinated could lower this risk.”

The study included nearly 1.3 million people aged 50 or older living in South Korea. Researchers gathered data, from 2012 onwards, on whether people received a shingle vaccine and combined this with data on their cardiovascular health and data on other factors that can influence health, such as age, sex, wealth and lifestyle.

The vaccine was a live zoster vaccine, meaning it contained a weakened form of the varicella zoster virus that causes shingles. In many countries, this type of vaccine is now being replaced with a non-live, recombinant vaccine, meaning it contains a protein from the varicella zoster virus.

The study showed that among people who received the vaccine, there was a 23% lower risk of cardiovascular events overall, with a 26% lower risk of major cardiovascular events (a stroke, heart attack or death from heart disease), a 26% lower risk of heart failure and a 22% lower risk of coronary heart disease.

The protective effect was strongest in the two to three years after the shingles vaccine was given, but researchers found that the protection lasted for up to eight years.

Professor Yon said: “Our study suggests that the shingles vaccine may help lower the risk of heart disease, even in people without known risk factors. This means that vaccination could offer health benefits beyond preventing shingles.

“There are several reasons why the shingles vaccine may help reduce heart disease. A shingles infection can cause blood vessel damage, inflammation and clot formation that can lead to heart disease. By preventing shingles, vaccination may lower these risks. Our study found stronger benefits in younger people, probably due to a better immune response, and in men, possibly due to differences in vaccine effectiveness.

“This is one of the largest and most comprehensive studies following a healthy general population over a period of up to 12 years. For the first time, this has allowed us to examine the association between shingles vaccination and 18 different types of cardiovascular disease. We were able to account for various other health conditions, lifestyle factors and socioeconomic status, making our findings more robust.

“However, as this study is based on an Asian cohort, the results may not apply to all populations. Since the live zoster vaccine is not suitable for everyone, more research on the recombinant vaccine is needed. While we conducted rigorous analysis, this study does not establish a direct causal relationship, so potential bias from other underlying factors should be considered.”

Professor Yon and his colleagues also plan to study the impact of the recombinant vaccine to see if it has similar benefits for reducing heart disease.

Source: European Society of Cardiology

Categories : VaccinesTags :

Funding Cuts Risk the Resurgence of Preventable Diseases, WHO Warns

On By ModernMedia
Photo by Mufid Majnun on Unsplash

The World Health Organization warns that global health funding cuts are paving the way for a resurgence of diseases that had been brought to the brink by vaccination.

One example of prior success is Africa’s “meningitis belt”, spanning parts of sub-Saharan Africa, where vaccination campaigns had successfully eliminated meningitis A. Likewise, yellow fever and related deaths were drastically cut by improved routine immunisation and emergency vaccine stockpiles.

The WHO says that this hard-won progress is now threatened. “Funding cuts to global health have put these hard-won gains in jeopardy,” warned Tedros Adhanom Ghebreyesus, WHO Director-General.

Outbreaks on the rise

In 2023, measles cases were estimated at more than 10.3 million – a 20% year-on-year increase. In a statement marking the beginning of World Immunization Week, the WHO, UN Children’s Fund UNICEF and their partners warned that this upward trend is expected to continue into 2025.

After years of declining cases in Africa thanks to improved vaccine access, yellow fever is also making a return. The start of 2025 has already seen a rise in outbreaks across the continent, with cases also confirmed in the Americas.

The threat of vaccine misinformation

Vaccination efforts are increasingly under pressure due to a combination of misinformation, population growth, humanitarian crises, and funding cuts.

Earlier this month, a WHO review across 108 countries found that nearly half are experiencing moderate to severe disruptions to vaccination campaigns, routine immunisations, and supply chains due to falling donor support.

“The global funding crisis is severely limiting our ability to vaccinate over 15 million vulnerable children in fragile and conflict-affected countries against measles,” said Catherine Russell, Executive Director of UNICEF.

High healthcare returns on vaccination

Vaccines save around 4.2 million lives each year, protecting against 14 different diseases. Almost half of those lives are saved in Africa.

Despite this, falling investment now risks the re-emergence of diseases once thought to be under control.

Health experts emphasise that immunisation is one of the most cost-effective health interventions. Every $1 invested in vaccines brings an estimated return of $54 through better health and economic productivity.

UNICEF, WHO, and their partners are calling on parents, the public, and political leaders to support immunisation programmes and ensure long-term investment in vaccines and public health systems.

Source: WHO

Categories : Cancer VaccinesTags :

New Method Boosts Cancer Vaccine Potency

On By ModernMedia
Squamous cancer cell being attacked by cytotoxic T cells. Image by National Cancer Institute on Unsplash

The concept of using vaccines to treat cancers has been around for several decades. A vaccine was first approved for prostate cancer in 2010, and another was approved in 2015 for melanoma. Since then, many therapeutic – as opposed to preventive – cancer vaccines have been in development, but none approved. One hurdle is the difficulty in finding antigens in tumours that look foreign enough to trigger an immune response.

Researchers at Tufts have now developed a cancer vaccine that makes tumour antigens more visible to the immune system, leading to a potent response and a lasting immunological memory that helps prevent tumour recurrence. Their vaccine avoids the need to hunt down a specific tumour antigen, instead relying on a digested mix of protein fragments called a lysate that can be generated from any solid tumour. 

The vaccine they produced worked against multiple solid tumours in animal models, including melanoma, triple-negative breast cancer, Lewis lung carcinoma, and clinically inoperable ovarian cancer.

Developed by a team led by postdoctoral scholar Yu Zhao and Qiaobing Xu, professor of biomedical engineering, the method builds on earlier work expressing specific antigens for an enhanced immune response by making lipid nanoparticles that carry mRNA into the lymphatic system. 

“We have significantly improved the cancer vaccine design by making it applicable to any solid tumour from which we can create a lysate, possibly even tumours of unknown origin, without having to select mRNA sequences, and then conjugating another component called AHPC that helps channel the protein fragments from the cancer cells into the immunological response pathway,” said Xu.

Unlike traditional vaccines designed to prevent infectious diseases caused by bacteria or viruses, cancer vaccines work by stimulating the body’s immune system to recognise and attack cancer cells. Unlike most vaccines against pathogens, they are designed to be therapeutic rather than preventive, acting to eliminate an existing disease. Some preventive cancer vaccines do exist, but they are generally targeted to viruses that are linked to cancers, such as HPV.

The key to the increased potency of the new cancer vaccine lies in its ability to direct tumour-derived antigens into a cellular pathway that efficiently presents the antigens to the immune system.

Rounding up the antigens and getting them into an antigen presenting cell like a macrophage or dendritic cell (the police stations, if we continue with the analogy) is generally an inefficient process for tumor antigens. This is where the Tufts research team applied a two-stage method to power up the process.

First, to make sure they round up all tumour proteins-of-interest, they modified the mix of tumour proteins with the AHPC molecule, which in turn recruits an enzyme to put a tag on the protein called a ubiquitin. It allows the cell to identify and process the protein into fragments for presentation to the immune system.

The researchers then packaged the AHPC-modified tumour proteins into tiny lipid nanoparticles, specifically designed to home in on lymph nodes, where most antigen-presenting cells can be found. 

Tested in animal models of melanoma, triple-negative breast cancer, Lewis lung carcinoma, and inoperable ovarian cancer, the vaccine elicited a strong response by cytotoxic T cells, which attack the growing tumours, suppressing further growth and metastasis.

“Fighting cancer has always been an arsenal approach,” said Xu. “Adding cancer vaccines to surgical excision, chemotherapy, and other drugs used to enhance cytotoxic T cell activity could lead to improved patient responses and longer-term prevention of cancer recurrence.”

Source: Tufts University

Categories : Respiratory Diseases VaccinesTags :

New Research Boosts Future Whooping Cough Vaccines

On By ModernMedia
Photo by CDC on Unsplash

Whooping cough, or pertussis, was once a leading cause of death for children worldwide before the introduction of vaccines in the 1940s. In the decades since, the bacterial disease was nearly eradicated in the U.S., with fatalities falling to double digits each year.

But the disease has made a troubling comeback in recent years as vaccine coverage declined after the COVID-19 pandemic. In 2024, several outbreaks left public health officials and hospitals scrambling to accommodate a sudden influx of patients, primarily infants, who are often too young to be vaccinated and suffer the most severe symptoms.

Now, new research from The University of Texas at Austin could aid in improving whooping cough vaccines to once again push this disease toward eradication by targeting two key weaknesses in the infection.

A New Target

Against this backdrop, a team of researchers, including members of UT’s McKetta Department of Chemical Engineering and Department of Molecular Biosciences, has made significant strides in understanding and enhancing pertussis immunity. One of the things that makes pertussis infections dangerous is pertussis toxin (PT), a chemical weapon produced by the bacteria that weakens a patient’s immune response and causes many of the severe symptoms associated with whooping cough.

The new research, described in a new study published in the Proceedings of the National Academy of Sciences, focuses on two powerful antibodies, hu11E6 and hu1B7, which neutralise the PT in different ways.

Using cutting-edge cryo-electron microscopy approaches, the researchers identified the specific epitopes on PT where these antibodies bind. Epitopes are chemical targets the immune system can zero in on to fight pathogens. Hu11E6 blocks the toxin from attaching to human cells by interfering with sugar-binding sites, while hu1B7 prevents the toxin from entering cells and causing harm. These findings are the first to precisely map these critical regions, providing a blueprint to improve vaccines.

“There are currently several promising new pertussis vaccines in the research and clinical trial phases,” said Jennifer Maynard, professor of chemical engineering at the Cockrell School of Engineering and corresponding author of the new study. “Our findings could be incorporated into future versions quite easily, improving overall effectiveness and longevity of protection.”

She pointed to innovations like mRNA technology used in the COVID-19 vaccine, as well as breakthroughs in using genetic engineering on pertussis toxin (PTgen) to generate safer and more potent new recombinant acellular pertussis vaccines as technologies preserving neutralizing epitopes that can combine with her team’s new findings.

“Training the immune system to target the most vulnerable sites on the toxin is expected to create more effective vaccines,” Maynard said. “And the more effective and longer-lasting a vaccine is, hopefully, the more people will take it.”

In addition to helping guide future vaccine designs, the hu1B7 and hu11E6 antibodies themselves hold promise as therapeutic medicines for infected and high-risk infants. Previous work by Maynard and colleagues show that they can prevent the lethal aspects of pertussis infection. UT researchers are actively seeking partnerships to develop ways to prevent lung damage and death in newborns exposed to the disease.

A Persistent Threat 

Caused by the bacterium Bordetella pertussis, whooping cough is infamous for its violent coughing fits, which can lead to complications like pneumonia, seizures, and even death, particularly in infants. One nickname for the disease is the 100-days cough because the painful coughing fits can linger for months, even in mild or moderate cases. The disease kills an estimated 200 000 people each year worldwide, most of them infants and children, and survivors of severe illness can be left with brain damage and lung scarring.

While modern vaccines have reduced the toll, their effectiveness wanes over time, with protection only lasting two to five years. Modern pertussis vaccines are acellular, which means they contain portions of the bacteria that train the immune system to recognize the pathogen, including PT.

Recent outbreaks of whooping cough around the world have stunned public health officials. This fall, New York City saw a 169% increase in whooping cough cases since 2023. Cases have increased 500% since 2019. Australia is currently suffering through the largest outbreak of whooping cough since the introduction of the vaccine in the 1940s, with an estimated 41,000 cases reported this year. 

Health officials point to missed initial and booster vaccinations as major contributors to the outbreaks.

Overcoming Hesitancy

While advances in fighting pertussis are exciting, they face a dual challenge: overcoming the biological complexity of pertussis and the societal hurdles of vaccine hesitancy. The most effective way to prevent pertussis in vulnerable newborns is for mothers to be vaccinated during pregnancy, which confers protection to the newborn until it is old enough to be vaccinated. According to the CDC, the full vaccination rate against pertussis in kindergarteners is typically over 90% in the US, but under 60% of mothers receive the vaccine during pregnancy. Skepticism about vaccine safety and slow normalization of routine vaccination after the COVID-19 pandemic has led to pockets of under-vaccinated communities and overall low protection of newborns, providing fertile ground for deadly outbreaks. This environment, coupled with the limitations of current vaccines, makes innovation essential.

Co-author Annalee W. Nguyen, a research professor in chemical engineering, emphasized the importance of prevention over treatment. “It’s always easier to prevent disease in a high-risk person,” she said. “Once someone is extremely ill, their immune system isn’t functioning well, and it’s harder to help them recover. Mothers have an incredible opportunity to shield their babies after they are born by getting a pertussis booster vaccination during pregnancy, and parents can continue to protect their families by working with their pediatrician to ensure children and teens are up-to-date on vaccinations.”

By focusing on neutralizing epitopes—areas where antibodies can effectively block the toxin—new vaccines can potentially provide stronger, longer-lasting immunity. This could help bolster public confidence in pertussis vaccines and curb the disease’s resurgence.

ource: University of Texas at Austin

Categories : Neurodegenerative Diseases VaccinesTags :

Study Strengthens Link between Shingles Vaccine and Lower Dementia Risk

On By ModernMedia
Photo by JD Mason on Unsplash

An unusual public health policy in Wales may have produced the strongest evidence yet that a vaccine can reduce the risk of dementia. In a new study led by Stanford Medicine, researchers analysing the health records of Welsh older adults discovered that those who received the shingles vaccine were 20% less likely to develop dementia over the next seven years than those who did not receive the vaccine.

The remarkable findings, published April 2 in Nature, support an emerging theory that viruses that affect the nervous system can increase the risk of dementia. If further confirmed, the new findings suggest that a preventive intervention for dementia is already close at hand.

Lifelong infection

Shingles, a viral infection that produces a painful rash, is caused by the same virus that causes chicken pox — varicella-zoster. After people contract chicken pox, usually in childhood, the virus stays dormant in the nerve cells for life. In people who are older or have weakened immune systems, the dormant virus can reactivate and cause shingles.

Dementia affects more than 55 million people worldwide, with an estimated 10 million new cases every year. Decades of dementia research has largely focused on the accumulation of plaques and tangles in the brains of people with Alzheimer’s, the most common form of dementia. But with no breakthroughs in prevention or treatment, some researchers are exploring other avenues — including the role of certain viral infections.

Previous studies based on health records have linked the shingles vaccine with lower dementia rates, but they could not account for a major source of bias: People who are vaccinated also tend to be more health conscious in myriad, difficult-to-measure ways. Behaviors such as diet and exercise, for instance, are known to influence dementia rates, but are not included in health records. 

“All these associational studies suffer from the basic problem that people who get vaccinated have different health behaviours than those who don’t,” said Pascal Geldsetzer, MD, PhD, assistant professor of medicine and senior author of the new study. “In general, they’re seen as not being solid enough evidence to make any recommendations on.”

Markus Eyting, PhD, and Min Xie, PhD, postdoctoral scholars in primary care and population health, are the study’s co-lead authors.

A natural experiment

But two years ago, Geldsetzer recognized a fortuitous “natural experiment” in the rollout of the shingles vaccine in Wales that seemed to sidestep the bias. The vaccine used at that time contained a live-attenuated, or weakened, form of the virus.

The vaccination program, which began Sept. 1, 2013, specified that anyone who was 79 on that date was eligible for the vaccine for one year. (People who were 78 would become eligible the next year for one year, and so on.) People who were 80 or older on Sept. 1, 2013, were out of luck — they would never become eligible for the vaccine. 

These rules, designed to ration the limited supply of the vaccine, also meant that the slight difference in age between 79- and 80-year-olds made all the difference in who had access to the vaccine. By comparing people who turned 80 just before Sept. 1, 2013, with people who turned 80 just after, the researchers could isolate the effect of being eligible for the vaccine.

The circumstances, well-documented in the country’s health records, were about as close to a randomized controlled trial as you could get without conducting one, Geldsetzer said. 

The researchers looked at the health records of more than 280 000 older adults who were 71 to 88 years old and did not have dementia at the start of the vaccination program. They focused their analysis on those closest to either side of the eligibility threshold — comparing people who turned 80 in the week before with those who turned 80 in the week after.

“We know that if you take a thousand people at random born in one week and a thousand people at random born a week later, there shouldn’t be anything different about them on average,” Geldsetzer said. “They are similar to each other apart from this tiny difference in age.”

The same proportion of both groups likely would have wanted to get the vaccine, but only half, those almost 80, were allowed to by the eligibility rules.

“What makes the study so powerful is that it’s essentially like a randomised trial with a control group — those a little bit too old to be eligible for the vaccine — and an intervention group — those just young enough to be eligible,” Geldsetzer said.

Protection against dementia

Over the next seven years, the researchers compared the health outcomes of people closest in age who were eligible and ineligible to receive the vaccine. By factoring in actual vaccination rates — about half of the population who were eligible received the vaccine, compared with almost none of the people who were ineligible — they could derive the effects of receiving the vaccine.

As expected, the vaccine reduced the occurrence over that seven-year period of shingles by about 37% for people who received the vaccine, similar to what had been found in clinical trials of the vaccine. (The live-attenuated vaccine’s effectiveness wanes over time.)

This huge protective signal was there, any which way you looked at the data.”

By 2020, one in eight older adults, who were by then 86 and 87, had been diagnosed with dementia. But those who received the shingles vaccine were 20% less likely to develop dementia than the unvaccinated.

“It was a really striking finding,” Geldsetzer said. “This huge protective signal was there, any which way you looked at the data.”

The scientists searched high and low for other variables that might have influenced dementia risk but found the two groups to be indistinguishable in all characteristics. There was no difference in the level of education between the people who were eligible and ineligible, for example. Those who were eligible were not more likely to get other vaccinations or preventive treatments, nor were they less likely to be diagnosed with other common health conditions, such as diabetes, heart disease and cancer.

The only difference was the drop in dementia diagnoses.

“Because of the unique way in which the vaccine was rolled out, bias in the analysis is much less likely than would usually be the case,” Geldsetzer said.

Nevertheless, his team analyzed the data in alternate ways — using different age ranges or looking only at deaths attributed to dementia, for example — but the link between vaccination and lower dementia rates remained.

“The signal in our data was so strong, so clear and so persistent,” he said.

Stronger response in women

In a further finding, the study showed that protection against dementia was much more pronounced in women than in men. This could be due to sex differences in immune response or in the way dementia develops, Geldsetzer said. Women on average have higher antibody responses to vaccination, for example, and shingles is more common in women than in men.

Whether the vaccine protects against dementia by revving up the immune system overall, by specifically reducing reactivations of the virus or by some other mechanism is still unknown.

Also unknown is whether a newer version of the vaccine, which contains only certain proteins from the virus and is more effective at preventing shingles, may have a similar or even greater impact on dementia.

Geldsetzer hopes the new findings will inspire more funding for this line of research.

“At least investing a subset of our resources into investigating these pathways could lead to breakthroughs in terms of treatment and prevention,” he said.

In the past two years, his team has replicated the Wales findings in health records from other countries, including England, Australia, New Zealand and Canada, that had similar rollouts of the vaccine. “We just keep seeing this strong protective signal for dementia in dataset after dataset,” he said.

But Geldsetzer has set his sights on a large, randomized controlled trial, which would provide the strongest proof of cause and effect. Participants would be randomly assigned to receive the live-attenuated vaccine or a placebo shot.

“It would be a very simple, pragmatic trial because we have a one-off intervention that we know is safe,” he said.

Geldsetzer is seeking philanthropic funding for the trial as the live-attenuated vaccine is no longer manufactured by pharmaceutical companies.  

And such a trial might not take long to see results. He pointed to a graph of the Wales data tracking the dementia rates of those who were eligible and ineligible for the vaccine. The two curves began to separate in about a year and a half.

Source: Stanford Medicine

Categories : VaccinesTags :

Why do False Claims that Vaccines Cause Autism Refuse to Die? Here are Nine Reasons

On By ModernMedia
Photo by Mika Baumeister on Unsplash

Sven Bölte, Karolinska Institutet

The idea that autism is caused by vaccines has recently been revived by Robert F. Kennedy Jr., the presumptive nominee for US Secretary of Health and Human Services, as well as by president-elect Donald Trump. When asked about vaccines at a recent press conference, Trump reportedly said there was “something wrong” with rising autism rates, adding: “We’re going to find out about it.”

From a research perspective, there is little left to discover about vaccines used in long-standing nationwide vaccine programmes, such as diphtheria, tetanus, whooping cough, polio, measles, mumps and rubella. There is strong data from different countries showing that these vaccines do not cause autism or underlie the vast increase in autism diagnosis rates. So why do suspicions that vaccines cause autism remain?

1. Unawareness of evidence

Reliably and accurately communicating research results to the public is difficult. Research results usually stay in small research or clinical communities. Research is rarely accessible and researchers have few incentives to communicate findings outside of their scientific channels.

Popular media is typically superficial and often primarily interested in controversy that generates public attention.

2. Challenges understanding the science

Science is complicated and in medicine there are rarely absolute truths. The public, however, might expect clear consensus or have difficulty grasping the precise nuance of the science and its findings.

Evidence shows that vaccines do not cause autism or are the reason for increasing diagnosis rates. But it is also in the nature of science that it can neither verify nor exclude totally that vaccines contribute to autism in single individuals.

They protect against viruses and bacteria that cause significant levels of death and human suffering. Vaccine programmes thus have a good risk-to-benefit ratio but are not perfect.

3. Doubts of science

The public may have doubts about science and scientists. Science often delivers probabilities and models, not absolute truths.

This might be disappointing or misunderstood as being no better than individual attitudes or opinions. Although not true for vaccines and autism, evidence can be contradictory and difficult to replicate, reinforcing public doubts.

The human need for immediate and simple explanations for complex issues fuels misbelief. The public may also mistrust scientists due to experiences of elitism, reports of researchers not following good scientific practices, and recurring conspiracies that scientists are accomplices of the pharmaceutical industry.

4. Invisible success of vaccine programmes

Vaccination programmes are among the most cost-effective public health interventions available and have averted deaths and long-term disease on a global level in the last decades.

This success has made most diseases invisible in many countries today. The absence of these diseases generates implicit beliefs that vaccinations are unnecessary.

5. Vaccines cause immune reaction

To reach the goal of immunisation, vaccines must cause an immune reaction. Therefore, a transient inconvenient physical reaction is a sign of success, and the logic of vaccination.

This alone might be counterintuitive and feed doubts about vaccinations. Compared to other drugs, only the side-effects are experienced, and the main effect is preventive, not immediately experienced.

6. Parallelism of events

Autism is a neurodevelopmental condition commonly appearing in the first years of life. Initial autistic behaviour may coincide by chance with vaccination time points or follow them and mix with immune reactions.

Making a connection between vaccination and the appearance of autism in these cases is inevitable. But correlation is not causation.

7. Drugs in infancy without an emergency

Ethical issues arise when people make decisions for others regarding drugs or feel coerced to take them. This is particularly true for infancy where parents must consent for their babies.

It can feel intuitively wrong to interfere with nature and invasive to give a series of shots to a fragile human being in early development in the absence of a medical emergency.

8. Actual harms from less-well established vaccines

Benefits and risks cannot be generalised across all vaccines. Vaccines that are part of long-standing vaccination programmes have good evidence to back them, indicating a convincing risk-benefit ratio.

New vaccines are not ensured in the same way. For instance, the swine flu vaccine during the 2009 pandemic is suspected of having caused 1300 cases of narcolepsy in Europe.

We must distinguish between well-established vaccines and those developed within a short period. It seems that necessary discussions around the safety of less well-established vaccines affect trust in established ones.

9. Polarised debate of vaccines

Open societies build on trust, freedom of speech and debate – but also on shared responsibility. Recent years have seen a polarisation of views around many topics, including vaccinations, not at least fuelled by the COVID crisis.

The urgency of the situation and need for solidarity left little space and time for discussion in society and marginalised or stigmatised even moderate sceptics. The latter has surely harmed trust in vaccines more generally.

Sven Bölte, Professor of Child and Adolescent Psychiatric Science, Karolinska Institutet

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Categories : Diet and Nutrition VaccinesTags :

Study in SA Children Finds Undernutrition may Weaken Measles Vaccination

On By ModernMedia
Photo by National Cancer Institute

Amid a global surge in measles cases, new research suggests that undernutrition may be exacerbating outbreaks in areas suffering from food insecurity. A study involving over 600 fully vaccinated children in South Africa found those who were undernourished had substantially lower levels of antibodies against measles.

Researchers from McGill University, UC Berkeley School of Public Health and the University of Pretoria tracked the children’s growth over time as an indicator of undernutrition and measured their antibody levels through blood tests. Children who were stunted around age three had an average of 24-per-cent-lower measles antibody levels by age five compared to their typical-sized peers.

The findings, published in Vaccine, suggest that undernutrition may affect the duration of vaccine protection.

This indicates that addressing child hunger could be a key piece of the puzzle in preventing viral outbreaks, said senior author Jonathan Chevrier, an Associate Professor at McGill.

A growing threat worldwide

Measles is a highly contagious viral infection that causes symptoms such as a rash, fever and cough, and can lead to severe complications, especially in young children. The disease is a threat in regions where it was once under control, including Canada, which in 2024 reported its highest number of cases in nearly a decade.

“Global measles cases declined from 2000 to 2016, but the trend reversed in 2018, driven in part by under-vaccination and the impact of the pandemic. Measles is now making a strong comeback in many parts of the world despite being preventable with vaccination and adequate immunity,” said co-author Brian Ward, Professor at McGill’s.

“We need to vaccinate children against infectious diseases that are preventable and ensure they are protected,” said first author Brenda Eskenazi, Professor at the University of California, Berkeley. “This is especially important now, given that many known diseases are expected to spread with climate change.”

About 22% of children under age five worldwide – approximately 148 million – were stunted in 2022, Chevrier added, with the highest rates in Asia and sub-Saharan Africa.

The team plans to monitor the children in the study as they grow older to understand whether the effects of early-life undernutrition persist.

Source: McGill University