̽��ֱ�� of Cambridge - vaccination

Birth by C-section more than doubles odds of measles vaccine failure

jg533 — Mon, 13 May 2024 09:01:04 +0000

A study by the ̽��ֱ�� of Cambridge, UK, and Fudan ̽��ֱ��, China, has found that a single dose of the measles jab is up to 2.6 times more likely to be completely ineffective in children born by C-section, compared to those born naturally.

Failure of the vaccine means that the child’s immune system does not produce antibodies to fight against measles infection, so they remain susceptible to the disease.

A second measles jab was found to induce a robust immunity against measles in C-section children.

Measles is a highly infectious disease, and even low vaccine failure rates can significantly increase the risk of an outbreak.

A potential reason for this effect is linked to the development of the infant’s gut microbiome – the vast collection of microbes that naturally live inside the gut. Other studies have shown that vaginal birth transfers a greater variety of microbes from mother to baby, which can boost the immune system.

“We’ve discovered that the way we’re born - either by C-section or natural birth - has long-term consequences on our immunity to diseases as we grow up,” said Professor Henrik Salje in the ̽��ֱ�� of Cambridge’s Department of Genetics, joint senior author of the report.

He added: “We know that a lot of children don't end up having their second measles jab, which is dangerous for them as individuals and for the wider population.

“Infants born by C-section are the ones we really want to be following up to make sure they get their second measles jab, because their first jab is much more likely to fail.”

̽��ֱ��results are published today in the journal Nature Microbiology.

At least 95% of the population needs to be fully vaccinated to keep measles under control but the UK is well below this, despite the Measles, Mumps and Rubella (MMR) vaccine being available through the NHS Routine Childhood Immunisation Programme.

An increasing number of women around the world are choosing to give birth by caesarean section: in the UK a third of all births are by C-section, in Brazil and Turkey over half of all children are born this way.

“With a C-section birth, children aren’t exposed to the mother’s microbiome in the same way as with a vaginal birth. We think this means they take longer to catch up in developing their gut microbiome, and with it, the ability of the immune system to be primed by vaccines against diseases including measles,” said Salje.

To get their results, the researchers used data from previous studies of over 1,500 children in Hunan, China, which included blood samples taken every few weeks from birth to the age of 12. This allowed them to see how levels of measles antibodies in the blood change over the first few years of life, including following vaccination.

They found that 12% of children born via caesarean section had no immune response to their first measles vaccination, as compared to 5% of children born by vaginal delivery. This means that many of the children born by C-section did still mount an immune response following their first vaccination.

Two doses of the measles jab are needed for the body to mount a long-lasting immune response and protect against measles. According to the World Health Organisation, in 2022 only 83% of the world's children had received one dose of measles vaccine by their first birthday – the lowest since 2008.

Salje said: “Vaccine hesitancy is really problematic, and measles is top of the list of diseases we’re worried about because it’s so infectious.”

Measles is one of the world’s most contagious diseases, spread by coughs and sneezes. It starts with cold-like symptoms and a rash, and can lead to serious complications including blindness, seizures, and death.

Before the measles vaccine was introduced in 1963, there were major measles epidemics every few years causing an estimated 2.6 million deaths each year.

̽��ֱ��research was funded by the National Natural Science Foundation of China.

Reference

Wang, W et al: ‘Dynamics of measles immunity from birth and following vaccination.’ Nature Microbiology, 13 May 2024. DOI: 10.1038/s41564-024-01694-x

Researchers say it is vital that children born by caesarean section receive two doses of the measles vaccine for robust protection against the disease.

CHBD / E+ / Getty Images

Very sick 5 year old little boy fighting measles infection, boy is laying in bed under the blanket with an agonizing expression, boy is covered with rash caused by virus.

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

Significant gaps in COVID-19 vaccine uptake may have led to over 7,000 hospitalisations and deaths

cjb250 — Mon, 15 Jan 2024 23:30:03 +0000

̽��ֱ��findings, published today in ̽��ֱ��Lancet, suggest that more than 7,000 hospitalisations and deaths might have been averted in summer 2022 if the UK had had better vaccine coverage.

With COVID-19 cases on the rise and a new variant strain recently identified, this research provides a timely insight into vaccine uptake and hesitancy and could inform policy-makers.

̽��ֱ��research relied on secure access to anonymised health data for everyone in all four nations of the UK, an advance which has only become possible during the pandemic.

Co-author Angela Wood, Professor of Health Data Science at the Victor Phillip Dahdaleh Heart & Lung Research Institute, ̽��ֱ�� of Cambridge and Associate Director of the British Heart Foundation Data Science Centre said: “This is the first epidemiological study to use individual-level anonymised health data covering the entire UK population. We have created a detailed, UK-wide picture of who is under-vaccinated against COVID-19 and the associated risks of under-vaccination.

“These results can be used to help create health policy and public health interventions to improve vaccine uptake. This approach could be extended to many other areas of medicine with great potential for new discoveries in the understanding and treatment of disease.”

Early COVID-19 vaccine rollout began strongly in the UK, with over 90% of the population over the age of 12 vaccinated with at least one dose by January 2022. However, rates of subsequent booster doses across the UK were not fully understood until now.

Scientists from England, Scotland, Northern Ireland and Wales – led by Health Data Research UK (HDR UK) and the ̽��ֱ�� of Edinburgh – studied securely-held, routinely collected NHS data from everyone over five years of age during 1 June to 30 September 2022. All data was de-identified and available only to approved researchers.

Data from across the four countries was then pooled and harmonised, a feat that was not possible until now. People were grouped by vaccine status, with under-vaccination defined as not having had all doses of a vaccine for which that a person was eligible.

̽��ֱ��findings reveal that the proportion of people who were under-vaccinated on 1 June 2022 ranged between one third and one half of the population – 45.7% for England, 49.8% for Northern Ireland, 34.2% for Scotland and 32.8% Wales.

Mathematical modelling indicated that 7,180 hospitalisations and deaths out of around 40,400 severe COVID-19 outcomes during four months in summer 2022 might have been averted, if the UK population was fully vaccinated.

Under-vaccination was related to significantly more hospitalisations and deaths across all age groups studied, with under-vaccinated people over 75 more than twice as likely to have a severe COVID-19 outcome than those who were fully protected.

̽��ֱ��highest rates of under-vaccination were found in younger people, men, people in areas of higher deprivation, and people of non-white ethnicity.

Researchers say the study – the largest ever study carried out in the UK – also ushers in a new era for UK science by overcoming challenges in uniting NHS data that is gathered and stored in different ways between devolved nations.

Professor Cathie Sudlow, Chief Scientist at Health Data Research UK and Director of the British Heart Foundation (BHF) Data Science Centre, said: “ ̽��ֱ��infrastructure now exists to make full use of the potential of routinely collected data in the NHS across the four nations of the UK. We believe that we could and should extend these approaches to many other areas of medicine, such as cancer, heart disease and diabetes to search for better understanding, prevention and treatment of disease."

Professor Sir Aziz Sheikh, Director of the Usher Institute at the ̽��ֱ�� of Edinburgh, HDR UK Research Director and study co-lead, said: “Large-scale data studies have been critical to pandemic management, allowing scientists to make policy-relevant findings at speed. COVID-19 vaccines save lives. As new variants emerge, this study will help to pinpoint groups of our society and areas of the country where public health campaigns should be focused and tailored for those communities.”

Reference
HDR UK COALESCE Consortium. Undervaccination and severe COVID-19 outcomes: meta-analysis of national cohort studies in England, Northern Ireland, Scotland, and Wales. Lancet; 16 Jan 2024; DOI: 10.1016/S0140-6736(23)02467-4

Adapted from a release from HDR-UK

Between a third and a half of the populations of the four UK nations had not had the recommended number of COVID vaccinations and boosters by summer 2022, according to the first research study to look at COVID-19 vaccine coverage of the entire UK population.

These results can be used to help create health policy and public health interventions to improve vaccine uptake

Angela Wood

KoldoyChris (Getty Images)

Girl being injected with COVID-19 vaccine

Yes

‘Ageing’ immune cell levels could predict how well we respond to vaccines

cjb250 — Tue, 27 Jun 2023 09:00:30 +0000

During the COVID-19 pandemic, it has become clear that some patients are better protected by vaccination than others. Many studies have shown that SARS-CoV-2 vaccines are less effective in people with weakened immune systems, but also that this effect is not uniform.

Vaccination involves priming the immune system to look for – and get rid of – invading pathogens, such as viruses and bacteria. In part, this involves stimulating the production of antibodies uniquely programmed to identify a particular invader. These antibodies are themselves produced by a type of immune cell known as a B cell.

One specific subset of B cells is known as age-associated B cells (ABCs). While, on average, less than one in 20 of a healthy individual’s B cells is an ABC, the proportion gradually increases as we get older. ̽��ֱ��reasons for this increase are not yet fully understood, but may include previous infections. Certain people with weakened immune systems accumulate ABCs still faster.

A team from the Medical Research Council (MRC) Toxicology Unit at the ̽��ֱ�� of Cambridge, led by Dr James Thaventhiran, examined ABCs from two very different patient groups – one comprised of people with an inherited condition that impairs the activity of their immune systems and a second group comprised of cancer patients taking immunotherapy drugs – as well as from healthy individuals.

Emily Horner, from Thaventhiran’s lab, explained the aim of this research: “By looking at patients’ B cells, we hoped to learn how we could stratify vulnerable patients – in other words, work out whether some patients were at greater risk from infection, even after vaccination, than others.”

̽��ֱ��researchers measured the relative proportion of ABCs compared to healthy B cells, and used a technique known as single cell RNA sequencing to look in detail at the activity of cells. They also teamed up with Dr Nicholas Matheson, from the Cambridge Institute of Therapeutic Immunology and Infectious Disease, to test how these factors influenced the ability of a vaccinated individual’s immune system to neutralise live SARS-CoV-2 virus.

Dr Juan Carlos Yam-Puc, also from the MRC Toxicology Unit, said: “What we found, much to our surprise, was that the age-associated B cells in these very different groups looked the same. ̽��ֱ��key difference was in the amount of these cells – the greater the proportion of ABCs in an individual’s blood, the less effective that individual was post-vaccination at neutralising the virus.”

This could help explain the variability seen within particular patient groups in responses to the vaccine: people with fewer ABCs are likely to respond better to vaccines.

Although the researchers examined ABCs in the context of responses to the SARS-CoV-2 vaccine, they believe that this phenomenon will almost certainly apply more widely, for example to the annual influenza vaccine.

Dr Pehuén Pereyra Gerber, who performed the experiments with live SARS-CoV-2 virus in Matheson’s lab, added: “Looking at blood levels of ABCs could tell us that person A should respond well to a vaccine, while person B might need a stronger vaccine or to be prioritised to receive a booster.”

Thaventhiran added: “Ultimately, this research could lead to the development of a clinical test to predict vaccine efficacy for immunodeficient patients, and for the population more generally.”

̽��ֱ��research was funded by the Medical Research Council, the Medical Research Foundation, and ̽��ֱ��Evelyn Trust.

Reference
Yam-Puc, JC et al. Age-Associated B cells predict impaired humoral immunity after COVID-19 vaccination in patients receiving immune checkpoint blockade. Nat Comms; 27 June 2023; DOI: 10.1038/s41467-023-38810-0

Cambridge scientists have identified a signature in the blood that could help predict how well an individual will respond to vaccines. ̽��ֱ��discovery, published today in Nature Communications, may explain why, even among vulnerable patient groups, some individuals have better responses to vaccines than others.

By looking at patients’ B cells, we hoped to learn how we could stratify vulnerable patients – in other words, work out whether some patients were at greater risk from infection, even after vaccination, than others

Emily Horner

Ed Us

Vaccination

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

Licence type:

Public Domain

Patients with SARS-CoV-2 Delta variant were more likely to be admitted to hospital compared to patients with Alpha variant

sc604 — Tue, 31 Aug 2021 09:29:45 +0000

In a new study published in ̽��ֱ��Lancet Infectious Diseases, researchers at Public Health England and the MRC Biostatistics Unit, ̽��ֱ�� of Cambridge, found that the estimated risk of hospital admission was two times higher for individuals diagnosed with the Delta variant of the SARS-CoV-2 virus, compared to those with the Alpha variant, after adjusting for differences in age, sex, ethnicity, deprivation, region of residence, date of positive test and vaccination status. When broadening the scope to look at the risk of either hospital admission or emergency care attendance, the risk was 1.45 times higher for Delta than Alpha.

This is the largest study to date to report on the risk of hospitalisation outcomes for cases with the Delta compared to the Alpha variant, using 43,338 Alpha and Delta cases confirmed through whole-genome sequencing who tested positive for COVID-19 between 29th March and 23rd May 2021. It is crucial to note that most of the Alpha and Delta cases in the study were unvaccinated or only partially vaccinated: 74% were unvaccinated, 24% were partially vaccinated, and only 2% were fully vaccinated. ̽��ֱ��results from this study therefore primarily tell us about the risk of hospital admission for those who are unvaccinated or partially vaccinated. Given the small number of hospitalised vaccinated cases, it has not been possible to estimate reliably if the hospitalisation risk differed between Delta and Alpha cases who had been fully vaccinated.

̽��ֱ��Delta variant is now the most common SARS-CoV-2 lineage in several higher-income and lower-income countries on all continents, currently accounting for more than 99% of new cases in England [2]. ̽��ֱ��evidence provided in this study therefore has implications for healthcare practice, planning and response in countries with ongoing or future Delta variant outbreaks, particularly in unvaccinated or partially vaccinated populations. As previous studies have shown Delta and Alpha spread more rapidly than previous variants [2–4], the combination of faster transmission and the current study’s finding of higher risk of severe disease requiring hospital admission in unvaccinated populations implies a more severe burden on healthcare of Delta outbreaks than of Alpha epidemics.

Previous studies have shown the available COVID-19 vaccines are highly effective against symptomatic infections with the Alpha variant [5], and are effective against symptomatic infections with the Delta variant, particularly after a full vaccination cycle with two doses [6,7]. For those who despite vaccination become infected, the vaccination protects against admission to hospital [8].

Dr Anne Presanis, Senior Statistician at the MRC Biostatistics Unit said:

"Our analysis highlights that in the absence of vaccination, any Delta outbreaks will impose a greater burden on healthcare than an Alpha epidemic. Getting fully vaccinated is crucial for reducing an individual’s risk of symptomatic infection with Delta in the first place, and, importantly, of reducing a Delta patient’s risk of severe illness and hospital admission.”

Dr Gavin Dabrera, Consultant Epidemiologist at Public Health England, said:

“This study confirms previous findings that people infected with Delta are significantly more likely to require hospitalisation than those with Alpha, although most cases included in the analysis were unvaccinated.

We already know that vaccination offers excellent protection against Delta and as this variant accounts for over 99% of COVID-19 cases in the UK, it is vital that those who have not received two doses of vaccine do so as soon as possible.

It is still important that if you have COVID-19 symptoms, stay home and get a PCR test as soon as possible.”

Reference:
Katherine A Twohig et al. 'Hospital admission and emergency care attendance risk for SARS-CoV-2 delta (B.1.617.2) compared with alpha (B.1.1.7) variants of concern: a cohort study.' ̽��ֱ��Lancet Infectious Diseases (2021). DOI: 10.1016/S1473-3099(21)00475-8

Largest study to date analysing more than 40,000 COVID-19 cases finds a two-fold increased risk of hospitalisation from delta versus alpha variant infections.

Getting fully vaccinated is crucial for reducing an individual’s risk of symptomatic infection with Delta in the first place, and, importantly, of reducing a Delta patient’s risk of severe illness and hospital admission

Anne Presanis

Steven Cornfield via Unsplash

Patient receives Covid-19 vaccine

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

Cost and scale of field trials for bovine TB vaccine may make them unfeasible

cjb250 — Thu, 07 Jun 2018 10:50:07 +0000

Instead, the researchers suggest that the scale and cost of estimating the effect of a vaccine on transmission could be dramatically reduced by using smaller, less expensive experiments in controlled settings – using as few as 200 animals.

Bovine TB is an infectious disease that affects livestock and wildlife in many parts of the world. In the UK, it is largely spread between infected cattle; badgers are also involved, transmitting to and receiving infection from cattle. Culls to keep badger populations small and reduce the likelihood of infecting cattle have proven controversial both with the public and among scientists.

̽��ֱ��UK has a policy of ‘test and slaughter’ using the tuberculin test and slaughter of infected animals. A vaccine (BCG) exists, but can cause some vaccinated cattle to test positive falsely. As such, the vaccine is currently illegal in Europe. Researchers are trying to develop a so-called ‘DIVA test’ (‘Differentiates Infected from Vaccinated Animals’) that minimises the number of false positives, but none are yet licensed for use in the UK.

̽��ֱ��European Union has said it would consider relaxing its laws against bovine TB vaccination if the UK government were able to prove that a vaccine is effective on farms. Any field trials would need to follow requirements set by the European Food Safety Authority (EFSA).

In research published today, a team of researchers led by the ̽��ֱ�� of Cambridge has shown using mathematical modelling that satisfying two key EFSA requirements would have profound implications for the likely benefits and necessary scale of any field trials.

̽��ֱ��first of these requirements is that vaccination must be used only as a supplement, rather than replacement, to the existing test-and-slaughter policy. But use of vaccination as a supplement means that a successful vaccine which reduces the overall burden and transmission of disease may nonetheless provide only limited benefit for farmers – false positives could still result in animals being slaughtered and restrictions being placed on a farm.

̽��ֱ��second of the EFSA requirements is that field trials must demonstrate the impact of vaccination on transmission rather than just protecting individual animals.

̽��ֱ��team’s models suggest that a three year trial with 100 herds should provide sufficient to demonstrate that vaccination protects individual cattle. Such a trial would be viable within the UK. However, demonstrating the impact on vaccination on transmission would be almost impossible because the spread of bovine TB in the UK is slow and unpredictable.

If BCG were to be licensed for use in cattle in the UK, vaccination would be at the discretion of individual farmers. Farmers would have to bear the costs of vaccination and testing, as well as the period of time under restrictions if animals test positive. This means that they would be less interested in the benefit to individual cattle and more interested in the benefits at the herd level. Herd immunity is such that, even if the vaccine is not 100% effective in every individual animal, the vaccine has an overall protective effect on the herd.

Trying to demonstrate an economic benefit for farmers would prove challenging. Using their models, the researchers show that herd-level effectiveness would be exceptionally difficult to estimate from partially-vaccinated herds, requiring a sample size in excess of 2,000 herds. ̽��ֱ��number of herds required could be reduced by a ‘three arm design’ that includes fully-vaccinated, partially-vaccinated and unvaccinated control herds; however, such a design would still require around 500 fully-vaccinated herds and controls – presenting potential logistical and financial barriers – yet would still have a high risk of failure.

Instead, the researchers propose a natural transmission experiment involving housing a mixture of vaccinated and unvaccinated cattle with a number of infected cattle. Such an experiment, they argue, could provide robust evaluation of both the efficacy and mode of action of vaccination using as few as 200 animals. This would help screen any prospective vaccines before larger, more expensive and otherwise riskier trials in the field.

“We already know that the BCG vaccine has the potential to protect cattle from bovine TB infection,” says Dr Andrew Conlan from the Department of Veterinary Medicine at the ̽��ֱ�� of Cambridge, the study’s first author. “Our results highlight the enormous scale of trials that would be necessary to evaluate BCG alongside continuing testing in the field.

“Such trials would be hugely expensive, and it isn’t even clear whether enough farms could be recruited. This scale could be dramatically reduced by using smaller scale natural transmission studies.”

Based on current knowledge of the likely efficacy of BCG, the researchers say their models do not predict a substantial benefit of vaccination at the herd level when used as a supplement to ongoing test-and-slaughter. Ruling out the use of vaccination as a replacement, rather than a supplement, to test-and-slaughter will inevitably limit the effectiveness and perceived benefits for farmers.

“If we could consider replacing test-and-slaughter with vaccination, then the economics becomes much more attractive, particularly those in lower income countries,” says Professor James Wood, Head of Cambridge’s Department of Veterinary Medicine. “Then, we would no longer need to carry out expensive testing, but could instead rely on passive surveillance through the slaughterhouses.”

̽��ֱ��study was funded by the UK Department for Environment, Food and Rural Affairs (Defra) and the Alborada Trust

Reference
Conlan, AJK, et al. ̽��ֱ��intractable challenge of evaluating cattle vaccination as a control for bovine Tuberculosis. eLife; 5 June 2018; DOI: 10.7554/eLife.27694.001

Field trials for a vaccine to protect cattle against bovine tuberculosis (bovine TB) would need to involve 500 herds – potentially as many as 75,000-100,000 cattle – to demonstrate cost effectiveness for farmers, concludes a study published today in the journal eLife.

Our results highlight the enormous scale of trials that would be necessary to evaluate BCG alongside continuing testing in the field. Such trials would be hugely expensive, and it isn’t even clear whether enough farms could be recruited

Andrew Conlan

Knarrhultpia

Curious cows

Researcher Profile: Dr Andrew Conlan

It may seem surprising to find a physicist in the Department of Veterinary Medicine, but this was how Dr Andrew Conlan began his career at the ̽��ֱ�� of Edinburgh. He is now an applied mathematician and statistician at in Cambridge’s Disease Dynamics Unit, engaged in work which he describes as “intensively multi-disciplinary”, requiring him to work within multiple environments with medics, veterinarians, farmers, policymakers – and even school children.

Andrew’s research sets out to use mathematics to predict the spread of infectious disease within populations and provide evidence to inform policy on the control of infectious diseases in humans and animals. His work centres around controlling the spread of diseases such as bovine TB and human diseases including, measles, whooping cough, scarlet fever, norovirus and meningitis.

“Policy decisions on the control of infectious diseases often have to be made quickly based on limited information and data,” he says. “I believe that government policy on infectious disease control should be based on evidence and good science.”

Although much of his research is office-based, involving analysing data, writing computational models and occasionally pen-and-paper work, he also does a lot of work with schools, working with pupils on research projects and delivering lessons on disease transmission.

“I’ve been involved in running citizen science projects for many years now, which have led to several peer reviewed papers on how social contact networks in schools could be useful to predict the spread of infectious disease,” he explains (while, ironically, nursing a cold picked up from his son, who had in turn picked it up at nursery). “I dreamed it up over a tea break with my colleague Ken Eames. At the time very little work had been down on contact patterns in school age children as they are a potentially vulnerable population that is difficult to access. We thought that getting them to do the research themselves and take ownership would be a way to address it – and it worked!”

Yes

Licence type:

Public Domain

Final biomedical trial on captive chimpanzees is first oral Ebola vaccine for saving wild apes

fpjl2 — Thu, 09 Mar 2017 12:06:41 +0000

̽��ֱ��results from the final biomedical research trial on captive chimpanzees for the foreseeable future have been published today in the journal Scientific Reports.

̽��ֱ��trial was of a vaccination for Ebola: the first orally administered vaccine for any disease developed specifically for the purpose of conserving wild apes.

In addition to poaching and forest loss, diseases such as Ebola and anthrax have devastated wild ape populations. Ebola alone is estimated to have killed one third of the world’s wild gorillas over the last three decades.

Now, new findings have shown an effective oral vaccine for Ebola in chimpanzees, and that the captive animals involved in the trial exhibited very few signs of stress as a result. Researchers say the work demonstrates a model that could be harnessed for other diseases and ape species in the wild.

However, after decades using chimpanzees to test vaccines destined for humans, changes in the law have seen enforced retirement of captive populations and the closing of chimpanzee research facilities in the US – the last developed country where biomedical testing on chimpanzees was legal.

In what researchers describe as a “horrible irony”, they say these reforms – a victory for long-standing campaigns by animal welfare groups – will ultimately prove detrimental to chimpanzees and gorillas in the wild, as any vaccination for wild animals must be tested in captivity first to ensure its safety.

Consequently, the promising new vaccine model may never progress to the point where it can be used to inoculate endangered wild apes, say the research team from the universities of Cambridge, UK, and Thomas Jefferson and Louisiana, US.

“In 2014 the world was gripped by fears of an Ebola virus pandemic. Yet few people realise that Ebola has already inflicted pandemic scale mortality on our closest relatives,” says lead researcher Dr Peter Walsh from the ̽��ֱ�� of Cambridge.

“African apes are also threatened by naturally occurring pathogens like anthrax, and the increasing overspill of human pathogens such as measles. A glimmer of hope lies in the fact that many of the disease threats are now vaccine preventable.

“We have developed a very promising tool for inoculating ape species against the myriad deadly diseases they face in the wild, but continued progress relies on access to a small number of captive animals.

“This may be the final vaccine trial on captive chimpanzees: a serious setback for efforts to protect our closest relatives from the pathogens that push them ever closer to extinction in the wild.”

Previous attempts to vaccinate wild apes have resorted to administering individual animals with hypodermic darts – a laborious task feasible for only a small number of apes habituated to human approach. By contrast, oral vaccines encased in appealingly edible baits could be distributed across wild ape territories to inoculate large numbers over longer periods.

Such an approach has already proved successful in other species: almost eliminating fox rabies (and the consequent need to cull foxes) across continental Europe.

̽��ֱ��latest study was carried out with ten chimpanzees in one of the last remaining chimpanzee research facilities in the US in New Iberia, Louisiana. Six received the oral vaccine, while four were injected as a control group.

All the animals displayed a robust immunity without side effects after 28 days – when the trial was terminated due to new Endangered Species Act regulations banning biomedical research on chimpanzees.

Throughout the trial, scientists closely monitored animal behaviour and physiology for signs of severe stress. Other than very minor weight loss (2% of body mass), they say that signs of trauma were “entirely absent”.

“Some pressure groups argue that all research on captive chimpanzees is tantamount to torture, not just because of procedures but also due to confinement,” says Walsh.

“Enclosures and animal care are now of a very high standard, with chimpanzees housed in large social spaces. ̽��ֱ��modest traces of stress we detected during our trial were akin to the values observed in college students anticipating exams.”

Captive chimpanzee trials are technically still legal in the US in instances that benefit the species. However, Walsh says that the limited funds available for conservation research makes it unviable for biomedical facilities to retain populations, while zoos and sanctuaries are either “ideologically opposed” or unwilling to risk any public backlash from testing.

Further work to enhance the vaccine, such as ensuring effectiveness after exposure to high tropical forest temperatures, may now never get done due to the closure of captive chimpanzee facilities.

“In an ideal world, there would be no need for captive chimpanzees,” says Walsh. “But this is not an ideal world. It is a world where diseases such as Ebola, along with rampant commercial poaching and habitat loss, are major contributors to rapidly declining wild ape populations.

“Oral vaccines offer a real opportunity to slow this decline. ̽��ֱ��major ethical debt we owe is not to a few captive animals, but to the survival of an entire species we are destroying in the wild: our closest relatives.”

Oral vaccine offers hope for ape species ravaged by Ebola and other diseases, as it can be widely dispersed to save more wild animals. However, scientists say recent law changes on captive chimpanzee testing may stop the conservation work in its tracks.

This may be the final vaccine trial on captive chimpanzees: a serious setback for efforts to protect our closest relatives from the pathogens that push them ever closer to extinction in the wild

Peter Walsh

Matthias Schnell

One of the captive chimpanzees in the research trial receiving the oral Ebola vaccination

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

Vaccination uptake among Traveller communities significantly lower than in general population

cjb250 — Sun, 18 Sep 2016 23:01:33 +0000

In a study published today in the Journal of Public Health, researchers from the Primary Care Unit at Cambridge examined records at a General Practice in the East of England to compare uptake of vaccination with the Traveller and non-Traveller communities.

For the majority of vaccines – including the MMR, rotavirus and combined Tetanus, diphtheria, polio and pertussis vaccines – only around five out of ten eligible children in the Traveller community had completed the relevant vaccination schedule, compared to nine out of ten children in the non-Traveller community.

Substantial health inequalities exist between the Traveller and general population, with the life expectancy of Travellers being 10-12 years lower than non-Traveller equivalents. Several studies have shown that there is lower vaccine uptake in Traveller children but this is the first study to present recent, accurate data in the UK.

̽��ֱ��findings show that this community is at risk of vaccine-preventable diseases. Ireland, Scotland and Wales and pockets of England are implementing strategies to improve vaccination coverage in the general population, but there is no national strategy in place in England to target Traveller, Gypsy and Roma communities.

̽��ֱ��2011 census recorded just under 58,000 Gypsies and Irish Travellers in England and Wales; however, the true number is more likely to be between 150,000 and 300,000, as many Travellers do not identify their ethnicity due to fear of discrimination.

“There is clearly much work needed to improve uptake of vaccinations among the Traveller community,” says Kathryn Dixon, a student doctor at the School of Clinical Medicine, ̽��ֱ�� of Cambridge. “Vaccinations are incredibly important to help protect children from potentially serious diseases, and we need to work with the Traveller communities to promote better understanding and appreciation of the long-term benefits.”

Literacy levels within the Traveller community can be low, meaning that information often spreads by word-of-mouth, according to the authors. This can lead to a rapid change in vaccine uptake if one person in the community hears something good or bad about vaccination from, for example, another Traveller site.

It was estimated in 2006 that around one in ten Travellers live in the East of England.

“There have been cases in the past of Travellers being refused healthcare by GPs, but the practice involved has made a particular effort to engage with the local Traveller communities,” explains Dr Tanya Blumenfeld, Senior Clinical Tutor at the ̽��ֱ��. “This could mean that vaccination rates elsewhere are even lower. We need to better understand the barriers that limit vaccination coverage and so help reduce the health inequalities that currently exist.”

Reference
Dixon, KC, Mullis, R, and Blumenfeld, T. Vaccine uptake in the Irish Travelling community: An audit of general practice records. Journal of Public Health; 19 Sept 206; DOI: 10.1093/pubmed/fdw088

Traveller communities have significantly lower uptake of vaccinations compared to the general population, suggesting that more work needs to be done to promote understanding and appreciation of the benefits of vaccination among this population, according to researchers at the ̽��ֱ�� of Cambridge.

Vaccinations are incredibly important to help protect children from potentially serious diseases, and we need to work with the Traveller communities to promote better understanding and appreciation of the long-term benefits

Kathryn Dixon

̽��ֱ��Advocacy Project

dale farm portaits 003

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

Licence type:

Attribution-Noncommercial-ShareAlike

Opinion: How your body clock helps determine whether you’ll get ill or not

Anonymous — Wed, 17 Aug 2016 10:55:31 +0000

From vitamin C and echinacea to warm clothes and antibacterial soap, there’s no shortage of ideas about how to prevent and manage colds and flu. Unfortunately, many of these are not based on solid scientific evidence. In fact, medical researchers are only starting to unravel the range of factors that affect our susceptibility to getting an infection. Now we have discovered that our body clock plays an important role – making us more prone to get infected at certain times of the day.

It is perhaps easy to forget that we have co-evolved on this planet with micro-organisms, including bacteria, which may be either beneficial or harmful to us. Similarly, viruses cannot copy themselves without help from our cells. Without us, they simply wouldn’t exist.

So what happens when a virus encounters a cell? First, it has to get in through a protective barrier called the cell membrane. Then it has to hijack the interior of the “host” cell to subvert it and divert all resources to copy itself millions of times. Once an army of identical clones is formed, it breaks out of the cell, usually destroying it in the process. Imagine millions of these new viruses then being able to do exactly the same to other cells nearby. ̽��ֱ��cycle goes on, with often rapid amplification of the virus through a tissue, and then through the body.

That’s if the virus had it all its own way … But there is always a battle in play between invading organisms and our bodies. Our immune system counteracts the invading organisms and will invoke mechanisms to stop the virus entering, replicating and spreading. This defence system works at the level of individual cells in the body, but also in specialised tissues of the body that are designed to mount a response to such invasions.

It now turns out that our body clock is also an important gatekeeper of virus infections. ̽��ֱ��body clock is an amazing piece of evolutionary biology. It’s thought that most organisms on our planet have a biological clock that keeps track of the 24-hour day. It can do this by orchestrating chemical reactions and genetic switches that rhythmically control thousands of genes in cells in the cell – turning about 15% of all genes on and off across the day and night.

Timely experiment

So why might viruses care about our body clock? Since our cells are miniature factories, making things that the virus must have to copy itself, the virus is less likely to succeed when the production line is shut down. This is what we tested in the laboratory, by infecting cells and mice at different times of the day. We found that viruses are less able to infect in the late afternoon. In contrast, in the early morning, our cells are hives of biosynthetic activity, at least from the virus’s viewpoint. So, if a virus tries to take over a cell in the early day, it is far more likely to succeed, and spread faster, than if it encounters a rather less favourable climate in the evening.

Perhaps even more interestingly, when the clockwork is disrupted, viruses are more prolific at taking over cells and tissues. Such “clock misalignment” can happen when we do shift work, get jet lagged, or experience the phenomenon of “social jet lag”, which is caused by changes in our sleep schedule on our days off. Therefore, it’s important to know about these interactions because it will undoubtedly help us to find ways to ensure better health for ourselves. For example, since we know shift workers are more likely to get infections, it might be a good idea to give them flu vaccinations.

Perhaps nightclub germs aren’t so threatening after all. *sax/Flickr, CC BY-SA

Knowing about the clock and viruses could also help us to design better public health measures to combat virus spread. You could imagine that during a pandemic limiting exposure during the early daytime could be a small but important intervention to try to prevent viral infection from taking hold. Indeed, a recent study by a team at the ̽��ֱ�� of Birmingham showed that vaccinating people against flu in the morning is more effective than in the evening. This principle could be the same for many unrelated viruses.

̽��ֱ��research could also help us crack a longstanding enigma – why do virus infections like flu happen more commonly in the winter months? It turns out that the very same molecular switch – called Bmal1 – that goes up and down in the day and night also changes according to the seasons, going up in the summer and down in the winter. When we artificially lower Bmal1 levels in mice and cells, the virus is able to infect more. As occurs on a daily basis, the waxing and waning of Bmal1 in our bodies could be a reason why we’re less likely to cope with viruses like flu in the winter.

So, if you’re desperate to avoid catching a flu virus that’s been going around the office, rather than trying to boost your immune system with various vitamins, you may want to try to simply work from home in the mornings.

Akhilesh Reddy, Wellcome Trust Senior Fellow in Clinical Sciences at the Department of Clinical Neurosciences, ̽��ֱ�� of Cambridge

This article was originally published on ̽��ֱ��Conversation. Read the original article.

̽��ֱ��opinions expressed in this article are those of the individual author(s) and do not represent the views of the ̽��ֱ�� of Cambridge.

Akhilesh Reddy (Department of Clinical Neurosciences) discusses how circadian rhythms can affect whether you get the flu.

Claus Rebler

Sick

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

For image use please see separate credits above.

Yes

Licence type:

Attribution-ShareAlike