Category: Vaccines

Categories : Diseases, Syndromes and Conditions VaccinesTags :

Flu Vaccination – Protection Beyond Flu For Healthcare Professionals And Patients

On By ModernMedia
Photo by Andrea Piacquadio on Pexels

The cooler months bring with them a surge in cases of influenza or ‘flu’. Flu infection causes up to 650 000 deaths globally each year, and the highest numbers occur in sub-Saharan Africa.1

Seasonal flu is characterised by a sudden onset of fever, cough (usually dry), headache, muscle and joint pain, severe malaise, sore throat and a runny nose. The cough can be severe and can last two or more weeks.2

South Africa’s seasonal flu usually has its highest number of recorded cases between May and September each year, with over 11 000 flu-related deaths occurring in the country annually.1 It is therefore important that healthcare professionals (HCPs) and high-risk population groups such as those living with chronic illnesses do not delay getting their flu shot this winter season.

Who is at risk of contracting severe flu, and of experiencing complications?

According to the National Institute for Communicable Diseases (NICD), the people most at risk for severe/complicated influenza include:1

  • Pregnant women and women up to 2 weeks postpartum
  • Young children (particularly those under 2 years of age)
  • Persons over the age of 65 years
  • Individuals who are morbidly obese (body mass index ≥40)
  • HIV-infected individuals
  • Individuals with tuberculosis
  • Persons of any age with chronic diseases:
  • lung diseases (e.g. asthma, chronic obstructive pulmonary disease)
  • immunosuppression (e.g. those on immunosuppressive medication, or who have cancer)
  • heart disease (e.g. congestive cardiac failure), except for hypertension
  • metabolic disorders (e.g. diabetes mellitus)
  • kidney or liver disease
  • neurological and neurodevelopmental conditions
  • abnormal production or structure of haemoglobin (e.g. sickle cell disease)
  • Those under 18 years receiving chronic aspirin therapy

HCPs are particularly vulnerable for contracting flu: a systematic review comparing the incidence of flu in healthy adults and HCPs found a significantly higher incidence in HCPs, since they are exposed to the virus via their patients.3 The World Health Organization (WHO) adds that “Because healthcare workers are dedicated individuals, they often come to work when they are sick, increasing the risk of transmission,” and therefore recommends that all HCPs are vaccinated against seasonal flu every autumn.3

The NICD indicates that it is particularly important to protect HCPs and ensure that they are able to continue to work and to reduce any additional burden on the health system.1

Most people recover from fever and other symptoms within a week of contracting the flu, without requiring medical attention. However, among high-risk groups, and those with serious medical conditions, flu can cause severe illness or death.2

Complicated influenza includes cases requiring hospital admission and/or with symptoms and signs of lower respiratory tract infection (hypoxaemia, dyspnoea, tachypnoea, lower chest wall indrawing and inability to feed), central nervous system involvement and/or a significant exacerbation of an underlying medical condition.1

When is the best time to get vaccinated?

Dr Lourens Terblanche, Medical Head: South Africa, Sanofi Vaccines, says: “People should ideally get vaccinated against flu before the flu season begins for the most effective coverage, although vaccination at any time during the flu season can still help protect against flu infections.”

“Influenza viruses evolve constantly, so twice a year the WHO makes recommendations to update vaccine compositions. HCPs and patients who are known to be at high risk for developing severe or complicated illness as a result of contracting the flu, should prioritise immunisation against flu every year, as recommended by the NICD,” says Dr Terblanche. “The vaccine is however available to any individual from the age of 6 months to help prevent influenza infection.”

How vaccination could protect beyond flu

Flu can impact many systems in the body, so flu vaccination can provide protection where these systems would have been affected. For example, complications of flu include a 10x higher risk of having a heart attack,4 an 8x higher risk of stroke,4 and an 8x greater risk of pneumonia in children under the age of 14,5 while persons with diabetes experience a 75% increase in glycaemic events.6

According to the US Centers for Disease Control (CDC), during the 2019-2020 season, flu vaccination averted 7.5 million cases of flu, 3.7 million medical visits, 105 000 flu-associated hospitalisations, and 6 300 deaths.7

A 2021 study by the CDC also showed that among adults hospitalised with flu, vaccinated patients had a 26% lower risk of having to go into the ICU and a 31% lower risk of death from flu, compared with those who were unvaccinated.7

“Flu vaccination is also essential considering the possible co-circulation of both the flu and SARS-Cov-2 or other respiratory pathogens. However, it is important to remember that the flu vaccine will not prevent COVID-19 and vice versa; therefore, it is important to ensure that HCPs and their patients are vaccinated against both. Simultaneous infection with flu and COVID-19 can result in severe disease,8” says Dr Terblanche.

Current guidance from the Department of Health regarding administering flu and COVID-19 vaccinations at the same time is that this may be done, if they are given in different arms.9

The WHO reports that there are still a number of myths about the flu vaccine10 – myths to which HCPs are not immune – including that ‘Flu is not serious, so I don’t need the vaccine’. The WHO responds as follows: “As many as 650 000 people a year can die of the flu. This only represents respiratory deaths, so the likely impact is even higher. Even healthy people can get the flu, but especially people whose immune systems are vulnerable. Most people will recover within a few weeks, but some can develop complications including sinus and ear infections, pneumonia, heart or brain inflammation.”

“It is good to be aware of the myths surrounding flu vaccination in order to encourage high-risk individuals to have their flu vaccine timeously,” says Dr Terblanche.

The quadrivalent Vaxigrip Tetra vaccine produced by Sanofi Pasteur complies with the WHO’s Southern Hemisphere recommendations for the 2023 season11 and protects against the following strains:

∙ an A/Sydney/5/2021 (H1N1)pdm09-like virus;

∙ an A/Darwin/9/2021 (H3N2)-like virus;

∙ a B/Austria/1359417/2021 (B/Victoria lineage)-like virus; and

∙ a B/Phuket/3073/2013 (B/Yamagata lineage)-like virus.

References

1. Blumberg L, Cohen C, Dawood H, et al. (2018). Flu NICD Recommendations for the diagnosis, prevention, management and public health response. Available from: http://www.nicd.ac.za/wp-content/uploads/2017/03/Flu-guidelines-rev_-23-April-2018.pdf. Accessed October 2019.

2. World Health Organization. What is seasonal influenza? Available from: https://www.who.int/news-room/questions-and-answers/item/how-can-i-avoid-getting-the-flu Accessed 7 March 2023.

3. WHO Fact sheet for health care workers: Protect yourself and your patients from influenza. Available from: https://www.euro.who.int/__data/assets/pdf_file/0011/261857/WHO_Factsheet_Healthworker_English-rev.pdf. Accessed 16 March 2023.

4. Warren-Gash C, et al. Laboratory-confirmed respiratory infections as triggers for acute myocardial infarction and stroke: a self-controlled case series analysis of national linked datasets from Scotland. Eur Respir J. 2018; DOI: 10.1183/13993003.01794-2017

5. Kubale J, et al. Individual-level Association of Influenza Infection With Subsequent Pneumonia: A Case-control and Prospective Cohort Study.  Clin Inf Dis. 2021; 73(11): e4288–e4295.

6. Samson SI, et al. Quantifying the Impact of Influenza Among Persons With Type 2 Diabetes Mellitus: A New Approach to Determine Medical and Physical Activity Impact. J Diabetes Sci Technol. 2019; 15(1):44-52.

7. CDC. Vaccine effectiveness: How well do the flu vaccines work? Available from: https://www.cdc.gov/flu/vaccines-work/vaccineeffect.htm. Accessed 14 March 2023.

8. Stowe J, et al. Interactions between SARS-CoV-2 and influenza, and the impact of coinfection on disease severity: a test-negative design. International Journal of Epidemiology 2021;1-10. doi: 10.1093/ije/dyab081.

9. Director General of Health. National COVID-19 Vaccination Programme Circular 3 of 2022 Co-administration of COVID-19 and other vaccines. Available from: https://sacoronavirus.co.za/wp-content/uploads/2022/02/Vaccination-Circular-3-of-2022-Co-administration-of-Covid-and-other-vaccines.pdf. Accessed 16 March 2023.

10. World Health Organization. 5 myths about the flu vaccine. Available from: https://www.who.int/news-room/spotlight/influenza-are-we-ready/5-myths-about-the-flu-vaccine. Accessed 8 March 2023.

11. World Health Organization. Recommended composition of influenza virus vaccines for use in the 2023 southern hemisphere influenza season. Available from:https://www.who.int/publications/m/item/recommended-composition-of-influenza-virus-vaccines-for-use-in-the-2023-southern-hemisphere-influenza-season. Accessed 16 March 2023.

Categories : COVID VaccinesTags :

SAHPRA Reports 3rd Fatal Case of Guillain-Barré Syndrome Following Janssen Vaccination

On By ModernMedia
Gloved hand holding vial of Janssen COVID vaccine
Photo by Spencer Davis on Unsplash

The South African Health Products Regulatory Authority (SAHPRA) issued media statements on 4 August 2022 and 12 September 2022, relating to two fatal cases of Guillain-Barré syndrome (GBS) following vaccination with COVID-19 Vaccine Janssen. SAHPRA has been informed of a third fatal case of GBS following vaccination with the same vaccine.

A causality assessment of the reported case was conducted by the National Immunisation Safety Expert Committee (NISEC) using the World Health Organization’s (WHO) methodology. Following investigations, the case was classified as a vaccine product-related event. The events reported in the vaccine recipient were consistent with the case definition of GBS and no other likely cause of GBS was identified at the time of illness.

As previously communicated, GBS is a very rare but potentially severe neurological adverse event that is associated with the administration of various vaccines and other medicines and can also be triggered by some bacterial or viral infections, including SARS-CoV-2. Symptoms of GBS range from mild to severe, and may include muscle weakness, muscle pain, numbness, and tingling. In many cases, GBS resolves with no serious after-effects, but in some cases GBS can cause serious or life-threatening problems.

Regulatory authorities have previously investigated reports of GBS associated with COVID-19 vaccines. They concluded that COVID-19 Vaccine Janssen may increase the risk of GBS. GBS is therefore listed as a rare adverse event in the professional information (PI) for COVID-19 Vaccine Janssen.

Investigations and causality assessment of all reported severe adverse events following immunisation (AEFI) with all COVID-19 vaccines are ongoing. The outcomes of these investigations and causality assessments will be shared with the public as soon as they are completed.

Important points to note

  • COVID-19 vaccines have consistently been shown to prevent severe forms of disease, hospitalisation and death. Based on the currently available evidence, SAHPRA has determined that the benefits of COVID- 19 vaccination far outweigh the very low risk of severe adverse events, including GBS. The public are strongly advised not to delay COVID-19 vaccination if eligible in terms of the national vaccination programme.
  • SAHPRA urges the public to report any suspected adverse events following the use of all medicines and vaccines. Reporting can be done at a health facility or by downloading the Med Safety App (https://medsafety.sahpra.org.za/), which is available for Android and iOS phones, or by calling the COVID-19 hotline at 0800 029 999. More information regarding AEFIs reported for the COVID-19 vaccines and how to report an AEFI is available from the SAHPRA website: https://aefi-reporting.sahpra.org.za/.
  • More information regarding AEFIs reported for the COVID-19 vaccines and how to report an AEFI is available from the SAHPRA website: https://aefi-reporting.sahpra.org.za/.

Source: SAHPRA

Categories : Paediatrics VaccinesTags :

New Vaccine Will Save Thousands of Children from Dying of Pneumonia

On By ModernMedia
Scanning electron micrograph of human respiratory syncytial virus (RSV) virions (colourised blue) and labelled with anti-RSV F protein/gold antibodies (colourised yellow) shedding from the surface of human lung epithelial A549 cells. Credit: National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH)

By James Stent for GroundUp

Respiratory syncytial virus (RSV) is a dangerous early childhood viral infection, but results of a vaccine trial promise to change things radically.

A new study published in the New England Journal of Medicine, the world’s most prestigious medical journal, on 5 April that examined the effect of an RSV vaccine on pregnant women found that it reduced the risk of severe lower respiratory tract infections in newborns by 82%.

RSV is the most common cause of acute lower respiratory infection – or pneumonia – in infants. Globally, it was responsible for just over 100,000 deaths (with a lower bound of 84,000 deaths and an upper bound of 126,000 deaths) of children under five in 2019. Of these deaths 45% were infants (younger than six months), and nearly all deaths occurred in lower income countries (half in Africa alone). In an article in Spotlight in June 2022, Professor Cheryl Cohen, head of the Centre for Respiratory Diseases and Meningitis at the National Institute for Communicable Diseases (NICD), said that, pre-COVID, RSV led to 44 615 hospitalisations and 490 deaths in children under five each year in South Africa.

South Africa is currently experiencing an RSV epidemic, with 301 cases detected this year, according to the NICD surveillance programme.

RSV causes cold-like symptoms, but can lead to severe symptoms like pneumonia. At present, there is no licensed RSV vaccine, though the virus was first identified in the 1960s.

The study was a phase three, double-blind trial (which compares a new treatment to standard care, and leads the way to regulatory approval and production) conducted in 18 countries, led by Beate Kampmann, Professor of Paediatric Infection and Immunity at the London School of Hygiene and Tropical Medicine, Shabir Madhi, Dean of the Faculty of Health Sciences and Professor of Vaccinology at the University of the Witwatersrand, and Iona Munjal, Director of Clinical Research & Development at Pfizer. It builds on earlier work by Madhi and others.

Women who were between 24 and 36 weeks pregnant were given an injection of a protein–based vaccine (RSVpreF) and a placebo. Pregnant women can passively transfer their immunity to viruses and diseases to their foetuses in utero.

They were then monitored to see if they suffered a severe RSV-associated lower respiratory tract illness that required medical attention, and if their newborns required medical attention for RSV-associated lower respiratory tract illness up to six months after birth.

A total of 7,358 women participated across the two trial groups, and 7,128 babies were monitored, and no safety concerns were identified over the course of the trial.

In November last year, Pfizer announced that it planned to submit a licence application to the US Food and Drug Administration after trials showed that the vaccine was highly effective at reducing severe RSV cases in the first 90 days of an infant’s life.

In a Twitter thread announcing the results, Madhi said that the next challenge would be to ensure that the vaccine is licensed across lower income countries, where most infant RSV deaths occur. Madhi said that there is a “moral responsibility on pharma to licence [the RSV] vaccine in LMIC [Lower and Middle Income Countries] at [an] affordable price.” Governments in poorer countries, “need to act to protect children in their counties by funding and deploying the vaccine timeously,” he said.

Madhi also informed GroundUp that coincidentally in the same issue of the New England Journal of Medicine, a medicine called nirsevimab was found to protect infants against RSV-associated hospitalisation and severe lower respiratory tract infections. Madhi and his team at Wits also participated in this trial.

This medicine is “administered as a single dose at the onset of RSV season,” Madhi explained. “The two approaches [the vaccine and nirsevimab] will be complementary.”

Republished from GroundUp under a Creative Commons Attribution-NoDerivatives 4.0 International License.

Source: GroundUp

Categories : Cancer VaccinesTags :

Transforming the Way Cancer Vaccines are Designed and Made

On By ModernMedia
Photo by Louise Reed on Unsplash

A new way to significantly increase the potency of almost any vaccine has been developed by researchers from the International Institute for Nanotechnology (IIN) at Northwestern University, which they describe in Nature.

The scientists used chemistry and nanotechnology to change the structural location of adjuvants and antigens on and within a nanoscale vaccine, greatly increasing vaccine performance. The antigen targets the immune system, and the adjuvant is a stimulator that increases the effectiveness of the antigen. 

“The work shows that vaccine structure and not just the components is a critical factor in determining vaccine efficacy,” said lead investigator Chad A. Mirkin, director of the IIN. “Where and how we position the antigens and adjuvant within a single architecture markedly changes how the immune system recognises and processes it.”

This new heightened emphasis on structure has the potential to improve the effectiveness of conventional cancer vaccines, which historically have not worked well, Mirkin said. 

Mirkin’s team has studied the effect of vaccine structure in the context of seven different types of cancer to date, including triple-negative breast cancer, papillomavirus-induced cervical cancer, melanoma, colon cancer and prostate cancer to determine the most effective architecture to treat each disease.   

Conventional vaccines take a blender approach   

With most conventional vaccines, the antigen and the adjuvant are simply blended and injected into a patient, giving no control over the vaccine structure, and, consequently, limited control over trafficking and processing of the vaccine components. Thus, there is no control over how well the vaccine works.  

“A challenge with conventional vaccines is that out of that blended mish mosh, an immune cell might pick up 50 antigens and one adjuvant or one antigen and 50 adjuvants,” said study author and former Northwestern postdoctoral associate Michelle Teplensky, who is now an assistant professor at Boston University. “But there must be an optimum ratio of each that would maximise the vaccine’s effectiveness.” 

Enter SNAs (spherical nucleic acids), which are the structural platform, invented and developed by Mirkin, used in this new class of modular vaccines. SNAs allow scientists to pinpoint exactly how many antigens and adjuvants are being delivered to cells. SNAs also enable scientists to tailor how these vaccine components are presented, and the rate at which they are processed. Such structural considerations, which greatly impact vaccine effectiveness, are largely ignored in conventional approaches.  

Vaccines developed through ‘rational vaccinology’ offer precise dosing for maximum effectiveness

Mirkin came up with this approach to systematically control antigen and adjuvant locations within modular vaccine architectures, and called it ‘rational vaccinology’. It is based on the concept that the structural presentation of vaccine components matters as much as the components themselves in driving efficacy.   

“Vaccines developed through rational vaccinology deliver the precise dose of antigen and adjuvant to every immune cell, so they are all equally primed to attack cancer cells,” said Mirkin. “If your immune cells are soldiers, a traditional vaccine leaves some unarmed; our vaccine arms them all with a powerful weapon with which to kill cancer. Which immune cell ‘soldiers’ do you want to attack your cancer cells?”

Building an (even) better vaccine  

The team developed a cancer vaccine that reduced tumour growth by more than four times compared to checkpoint inhibitor monotherapy, and led to a 40% extension in median survival.  

By reconfiguring the architecture of a vaccine containing multiple targets, the SNA enables the immune system to find tumour cells. The team investigated differences in how well two antigens were recognised by the immune system depending on their placement, on the core or perimeter, of the SNA structure. For an SNA with optimum placement, they could increase the immune response and how quickly the nanovaccine triggered cytokine (an immune cell protein) production to boost T cells attacking the cancer cells. The scientists also studied how the different placements affected the immune system’s ability to remember the invader, and whether the memory was long-term.  

“Where and how we position the antigens and adjuvant within a single architecture markedly changes how the immune system recognises and processes it,” Mirkin said. 

The most powerful structure throws two punches to outsmart the tumour  

The study data show that attaching two different antigens to an SNA comprising a shell of adjuvant was the most potent approach for a cancer vaccine structure. These engineered SNA nanostructures stalled tumour growth in multiple animal models.   

“It is remarkable,” Mirkin said. “When altering the placement of antigens in two vaccines that are nearly identical from a compositional standpoint, the treatment benefit against tumours is dramatically changed. One vaccine is potent and useful, while the other is much less effective.”  

Many current cancer vaccines are designed to primarily activate cytotoxic T cells, only one defence against a cancer cell. Because tumour cells are always mutating, they can easily escape this immune cell surveillance, quickly rendering the vaccine ineffective. The odds are higher that the T cell will recognise a mutating cancer cell if it has more antigens to recognise it.   

“You need more than one type of T cell activated, so you can more easily attack a tumour cell,” Teplensky said. “The more types of cells the immune system has to go after tumours, the better. Vaccines consisting of multiple antigens targeting multiple immune cell types are necessary to induce enhanced and long-lasting tumour remission.”  

Another advantage of the rational vaccinology approach, especially when used with a nanostructure like an SNA, is that it’s easy to alter the structure of a vaccine to go after a different type of disease. Mirkin said they simply switch out a peptide, a snippet of a cancer protein with a chemical handle that “clips” onto the structure, not unlike adding a new charm to a bracelet.   

Towards the most effective vaccine for any cancer type 

“The collective importance of this work is that it lays the foundation for developing the most effective forms of vaccine for almost any type of cancer,” Teplensky said. “It is about redefining how we develop vaccines across the board, including ones for infectious diseases.” 

In a previously published paper, Mirkin, Teplensky and colleagues demonstrated the importance of vaccine structure for SARS-CoV-2 by creating vaccines that exhibited protective immunity in 100% of animals against a lethal viral infection.  

“Small changes in antigen placement on a vaccine significantly elevate cell-to-cell communication, cross-talk and cell synergy,” Mirkin said. “The developments made in this work provide a path forward to rethinking the design of vaccines for cancer and other diseases as a whole.”   

Source: Northwestern University

Categories : HIV VaccinesTags :

Trial of New HIV Vaccine Ended Early due to Ineffectiveness

On By ModernMedia
HIV themed candle
Image by Sergey Mikheev on Unsplash

The investigational HIV ‘Mosaico’ vaccine regimen was safe but did not provide protection against HIV acquisition, an independent data and safety monitoring board (DSMB) has determined. Based on the DSMB’s recommendation, the study will be discontinued. This follows the failure of the similar ‘Imbokodo’ vaccine in sub-Saharan Africa.

The HPX3002/HVTN 706, or ‘Mosaico’ Phase 3 clinical trial began in 2019 and involved 3900 volunteers in Europe, North America and South America. The participants were men who have sex with men (MSM) or transgender people.

The Janssen-developed vaccine was based on ‘mosaic’ immunogens, which are vaccine components featuring elements of multiple HIV subtypes, in order to induce immune responses against a wide variety of global HIV strains. The investigational vaccine regimen consisted of four injections over a year of Ad26.Mos4.HIV, with the mosaic immunogens delivered by a common-cold virus (adenovirus serotype 26, or Ad26). The final two vaccinations were accompanied by a bivalent (two-component) HIV envelope protein formulation, combining clade C gp140 and mosaic gp140 envelope proteins, adjuvanted by aluminium phosphate to boost immune responses. All study vaccinations were completed in October 2022.

In early studies, this vaccine combination induced strong antibody and T-cell responses and protected monkeys exposed to SIV, the simian cousin of HIV. The vaccines however failed to stimulate production of broadly neutralising antibodies (bNAbs) that disable multiple HIV variants, according to aidsmap. In that study, the vaccine conferred a 25.2% effectiveness in protection, but not the 50% necessary for an effective vaccine.

In its scheduled data review, the DSMB determined there were no safety issues with the experimental vaccine regimen. However, the number of HIV infections were equivalent between the vaccine and placebo arms of the study. During the clinical trial, all participants were offered comprehensive HIV prevention tools, including pre-exposure prophylaxis, or PrEP. Study staff ensured that participants who acquired HIV during the trial were promptly referred for medical care and treatment. Participants are being notified of the findings, and further analyses of the study data are planned.

The Mosaico findings track with developments in the Phase 2b ‘Imbokodo’ (HPX2008/HVTN 705) clinical trial, which was testing a similar HIV vaccine regimen in young women in sub-Saharan Africa. A DSMB determined in 2021 that the experimental vaccine regimen in that study was also safe but ineffective in protecting against HIV acquisition.

Source: NIH/National Institute of Allergy and Infectious Diseases

Categories : VaccinesTags :

Mucosal Vaccines Could be the Next Step Against Respiratory Viruses

On By ModernMedia
Image by Arek Socha from Pixabay

Vaccines that provide long-lasting protection against influenza, coronaviruses and respiratory syncytial virus (RSV) have proved exceptionally difficult to develop. In a new review article in Cell Host & Microbe, NIH researchers explore the challenges and outline approaches to improved vaccines and describe a promising path forward: mucosal vaccines.

Unlike the respiratory viruses that cause measles, mumps and rubella — for which vaccination or recovery from illness provides decades-long protection against future infection – flu, RSV, SARS-CoV-2 and “common cold” coronaviruses share several characteristics that enable them to cause repeated re-infections. These include very short incubation periods, rapid host-to-host transmission and replication in the nasal mucosa rather than throughout the body. This last feature – non-systemic replication – means these viruses do not stimulate the full force of the adaptive immune response, which typically takes a week or more to mount.

A next generation of improved vaccines for mucosa-replicating viruses will require advances in understanding on several fronts, the authors say. For instance, more must be learned about interactions between flu viruses, coronaviruses and RSV and the components of the immune response that operate largely or exclusively in the upper respiratory system. Over time, these interactions have evolved and led to “immune tolerance,” wherein the human host tolerates transient, limited infections by viruses that are generally non-lethal to avoid the destructive consequences of an all-out immune system attack.

The authors note that mucosal immunisation appears to be an optimal route of vaccination for the viruses of interest, when feasible. However, to develop useful mucosal vaccines, significant knowledge gaps must be filled including finding ideal vaccine formulations; determining dosage size, frequency and timing; and developing techniques for overcoming immune tolerance.

Source: NIH/National Institute of Allergy and Infectious Diseases

Categories : COVID VaccinesTags :

Increase in Global Willingness to Accept COVID Vaccines

On By ModernMedia
Vaccine injection
Image source: NCI on Unsplash

Global COVID vaccine acceptance increased from 75.2% in 2021 to 79.1% in 2022, according to a new survey of 23 countries accounting for more than 60% of the world’s population, published today in Nature Medicine. It was not all good news, though: vaccine hesitancy increased in eight countries including South Africa, and nearly one in eight vaccinated respondents were hesitant about receiving a booster dose.

This third annual study reveals a wide variability between countries and suggests a need to tailor communication strategies to effectively address vaccine hesitancy.

“The pandemic is not over, and authorities must urgently address vaccine hesitancy and resistance as part of their COVID prevention and mitigation strategy,” says CUNY Graduate School of Public Health and Health Policy (CUNY SPH) Senior Scholar Jeffrey V. Lazarus. “But to do so effectively, policymakers need solid data on vaccine hesitancy trends and drivers.”

To provide these data, an international collaboration led by Lazarus and CUNY SPH Dean Ayman El-Mohandes performed a series of surveys starting in 2020 in 23 countries which were impacted significantly by the pandemic, including the United States as well as South Africa and Brazil.

Of the 23 000 respondents (1000 per country surveyed), 79.1% were willing to accept vaccination, up 5.2% from June 2021. The willingness of parents to vaccinate their children also increased slightly, from 67.6% in 2021 to 69.5% in 2022. However, eight countries saw an increase in hesitancy (from 1.0% in the UK to 21.1% in South Africa). Worryingly, almost one in eight (12.1%) vaccinated respondents were hesitant about booster doses, and booster hesitancy was higher among the 18–29 age groups.

“We must remain vigilant in tracking this data, containing COVID variants and addressing hesitancy, which may challenge future routine COVID immunisation programs,” says Dean El-Mohandes, the study’s senior author.

The survey also provides new information on COVID treatments received. Globally, ivermectin was used as frequently as other approved medications, despite the fact that it is not recommended by the WHO or other agencies to prevent or treat COVID  

Also of note, almost 40% of respondents reported paying less attention to new COVID information than before, and there was less support for vaccine mandates. 

In some countries, vaccine hesitancy was associated with being female (for example in China, Poland, Russia), having no university degree (in France, Poland, South Africa, Sweden, or the US), or lower income (in Canada, Germany, Turkey or the UK). Also, the profile of people paying less attention to the pandemic varied between countries.

“Our results show that public health strategies to enhance booster coverage will need to be more sophisticated and adaptable for each setting and target population,” says Lazarus, also head of the Health Systems Research Group at ISGlobal. “Strategies to enhance vaccine acceptance should include messages that emphasise compassion over fear and use trusted messengers, particularly healthcare workers.”

The data provided by these surveys may offer insight to policymakers and public health officials in addressing COVID vaccine hesitancy. The study follows on the heels of a global consensus statement on ending COVID as a public health threat that Lazarus, El-Mohandes and 364 co-authors from 112 countries published in Nature in November.

Source: CUNY SPH

Categories : VaccinesTags :

Antibody Discovery Suggests a Possible New Vaccine for Strep A

On By ModernMedia
Streptococcus pyrogenese bound to human neutrophil
Streptococcus pyogenese bound to a human neutrophil. Credit: National Institute of Allergy and Infectious Diseases, National Institutes of Health

Researchers at Lund University in Sweden have discovered an antibody that could potentially protect against Strep A infection, as well as a rare form of antibody binding, that leads to an effective immune response against bacteria. The discovery could explain why so many Group A strep vaccines have failed.

The results are published in EMBO Molecular Medicine.

Group A streptococci have several ways in which they evade the body’s immune system and, when they infect us, can cause both common throat infections (strep throat), scarlet fever, sepsis, swine pox and skin infections. So far, antibiotics work against these bacteria, but should they become resistant, they will pose a major public health threat.

One strategy that the scientific community uses to find new ways of fighting bacterial infections is to create target-seeking antibodies. First, the antibodies that the body’s immune system produces in the event of an infection are mapped, and then their effect on the immune system is studied. In this way, antibodies can be identified that can be used both for preventive treatment and for treatment during an ongoing infection. It is a difficult process, though, with many attempts to develop antibody-based treatments against Strep A ending in failure.

The current study shows an unexpected way that antibodies interact with group A streptococci and, more specifically, how they hook onto the probably most important bacterial protein, the M protein, on the cell surface.

“We found that it happens in a way that has never been described before. Normally, an antibody binds via one of its two Y arms to its target protein at a single site, regardless of which of the two arms is used for binding. But what we have seen- and this is vital information – is that the two Y arms can recognise and hook on to two different places on the same target protein,” explains study author Pontus Nordenfelt.

This means that the two arms of the antibody – which are identical – can bind to two different sites on a target protein. It turns out that it is precisely this type of binding that is required for effective protection, and since it is probably rare, the researchers believe, it could explain why so many vaccine attempts have been unsuccessful. It could also be a reason why the bacteria manage to escape the immune system.

It has long been known that the streptococcal bacteria’s M protein is of great importance for how disease occurs and develops in the body. Finding an antibody that attaches to this protein, thereby flagging it up to the immune system, can prevent the bacteria from infecting the body’s cells. Since we know that the human body can fight the infection, such antibodies exist, but it is hard to locate them.

The researchers therefore focused on examining antibodies in patients who had recovered from group A streptococcal infection. They managed to identify three so-called monoclonal antibodies from a patient who recovered from a Strep A infection. Monoclonal antibodies are identical copies of each other, and in this case target a single protein (the M protein) of the group A streptococci. The researchers then investigated in animal studies whether it is possible to use the antibodies to strengthen the immune system in its fight against group A streptococcus. It turned out that the antibody with the newly discovered binding mechanism produced a strong immune response against the bacteria. The researchers have now applied for a patent based on the findings in the article, and will continue to study the antibody.

“This opens up possibilities where previous vaccine attempts have failed and means that the monoclonal antibody we used has the potential to protect against infection,” concludes study author Wael Bahnan.

Source: Lund University

Categories : Substance Use VaccinesTags :

To Fight the Opioid Epidemic, Researchers Create a Vaccine that Blocks Fentanyl

On By ModernMedia
Photo by Pharmacy Images on Unsplash

Researchers have developed a vaccine that blocks fentanyl’s to enter the brain, thus eliminating the dangerous synthetic opioid’s “high”. The breakthrough discovery, reported in the journal Pharmaceutics, could have major implications for the rampant problem of opioid addiction by becoming a relapse prevention agent for people trying to quit using opioids.

While Opioid Use Disorder (OUD) is treatable, studies estimate that 80% of those dependent on the drug suffer a relapse. Fentanyl is 50 times stronger than heroin and 100 times stronger than morphine. Consumption of about 2mg of fentanyl (the size of two grains of rice) is likely to be fatal depending on bodyweight. Current treatments for OUD are methadone, buprenorphine and naltrexone. Naloxone is given in opioid overdose situations and can temporarily reverse the effects of the opioids.

“We believe these findings could have a significant impact on a very serious problem plaguing society for years – opioid misuse. Our vaccine is able to generate anti-fentanyl antibodies that bind to the consumed fentanyl and prevent it from entering the brain, allowing it to be eliminated out of the body via the kidneys. Thus, the individual will not feel the euphoric effects and can ‘get back on the wagon’ to sobriety,” said lead author Colin Haile, a research associate professor of psychology at University of Houston.

No any adverse side effects from the vaccine were observed in trial animals. The team plans to start manufacturing clinical-grade vaccine in the coming months with clinical trials in humans planned soon.

Fentanyl is an especially dangerous threat because it is often added to street drugs like cocaine, methamphetamine and other opioids, such as oxycodone and hydrocodone/acetaminophen pills, and even to counterfeit benzodiazepines like Xanax. These counterfeit drugs laced with fentanyl add to the amount of fentanyl overdoses in individuals who do not ordinarily consume opioids.

“The anti-fentanyl antibodies were specific to fentanyl and a fentanyl derivative and did not cross-react with other opioids, such as morphine. That means a vaccinated person would still be able to be treated for pain relief with other opioids,” said Haile.

The vaccine tested contains an adjuvant derived from E. coli named dmLT. An adjuvant molecule boosts the immune system’s response to vaccines, a critical component for the effectiveness of anti-addiction vaccines.

Therese Kosten, professor of psychology and director of the Developmental, Cognitive & Behavioral Neuroscience program at UH, calls the new vaccine a potential “game changer.”

“Fentanyl use and overdose is a particular treatment challenge that is not adequately addressed with current medications because of its pharmacodynamics and managing acute overdose with the short-acting naloxone is not appropriately effective as multiple doses of naloxone are often needed to reverse fentanyl’s fatal effects,” said Kosten, senior author of the study.

Source: University of Houston

Categories : Cardiovascular Disease VaccinesTags :

Flu Vaccine Reduces Early Mortality in HF Patients

On By ModernMedia

In a study published in The Lancet Global Health, an international team of researchers has found that influenza vaccines greatly reduce both pneumonia and cardiovascular complications in people with heart failure.

“If you have heart failure, you should get your flu shot because it can save your life – that is what we found in this study,” said the study’s principal investigator Mark Loeb. “It is underappreciated that influenza vaccine can save people from cardiovascular death.”

The study showed that over the entire year the influenza vaccine reduced pneumonia by 40% and hospitalisation by 15% in patients with HF. During influenza season in autumn and winter, the influenza vaccine reduced deaths by 20% in these patients.

Data gathered during flu season also showed the vaccine helped protect against cardiovascular complications, such as heart attacks and strokes.

Trial investigators tracked more than 5000 patients with HF in 10 countries across Africa, Asia and the Middle East, where few people have regular influenza vaccination. They received either an influenza vaccine or a placebo annually between June 2015 and November 2021.

While the flu has long been associated with an increased risk of life-threatening cardiovascular events, Loeb said that people with heart failure are already vulnerable to poor health outcomes. Patients with the condition have a 50% chance of dying within five years, while 20% are hospitalised for cardiovascular complications every year.

“Importantly, we looked at low and middle-income countries where 80 per cent of cardiovascular disease occurs and where flu vaccination rates are low.”

Salim Yusuf, executive director of PHRI and an author of the study said: “The flu shot should be part of the standard practise in people with heart failure given how simple, inexpensive and safe it is. Avoiding one sixth of deaths from heart disease and preventing hospitalizations makes it very cost effective and that can have an important public health and clinical impact.”

The study from McMaster University and partners marks the first clinical trial of the flu vaccine’s effectiveness in patients with HF.

Source: McMaster University