Day: November 27, 2023

Half Dose of COVID Booster Yields Similar Immune Response to Full One

Photo by Gustavo Fring on Pexels

Reducing the dose of a widely used COVID booster vaccine produces a similar immune response in adults to a full-dose with fewer side effects, according to a new study published in The Lancet Regional Health – Western Pacific. The research found that a half dose of a Pfizer COVID booster vaccine elicited a non-inferior immune response to a full dose in Mongolian adults who previously had AstraZeneca or Sinopharm COVID shots. But it found half-dose boosting may be less effective in adults primed with the Sputnik V COVID vaccine. 

The research, led by Murdoch Children’s Research Institute (MCRI) and the National Centre for Communicable Diseases in Mongolia, is part of an international clinical trial investigating the different COVID booster shot approaches to help guide future vaccination strategies. 

The first batch of findings, and involving 601 participants over 18 years old from Mongolia, reports on the initial responses seen 28-days after vaccination. The study is the first of its kind to assess and compare COVID-19 vaccines widely used in low- and middle-income countries.

MCRI Professor Kim Mulholland, who also sits on the WHO SAGE committee, said the study found that fractional doses elicited an immune response that was non-inferior to a full dose with fewer side effects and was less costly.

“Fractional dosing may improve COVID booster acceptability and uptake and reduce the per-dose cost of COVID-19 booster programs,” he said. “Policymakers and immunisation advisory committees can draw upon this data to make flexible boosting schedules decisions.”

The study found that participants receiving a half dose reported fewer local reactions than those receiving full doses (60% versus 72%) including less pain and tenderness. They also reported fewer systemic reactions (25% vs 32%) including less fevers, vomiting, diarrhoea and headaches. 

The cohort will be followed up at six and 12 months with the data to answer key questions on other aspects of the immune response including the rate of waning and breakthrough infections. 

Source: Murdoch Children’s Hospital

Europe’s Heat-related Deaths in 2022 may Exceed 70 000

Photo by Ketut Subiyanto

The burden of heat-related mortality during the summer of 2022 in Europe may have exceeded 70 000 deaths according to a study led by the Barcelona Institute for Global Health (ISGlobal). The authors of the study, published in The Lancet Regional Health – Europe, revised upwards initial estimates of the mortality associated with record temperatures in 2022 on the European continent.

In an earlier study, the same team used epidemiological models applied to weekly temperature and mortality data in 823 regions in 35 European countries and estimated the number of heat-related premature deaths in 2022 to be 62 862. In that study, the authors acknowledged that the use of weekly data would be expected to underestimate heat-related mortality, and pointed out that daily time-series data are required to accurately estimate the impact of high temperatures on mortality.

The objective of the new study was to develop a theoretical framework that could quantify the errors inherent to aggregated data, such as weekly and monthly temperature and mortality time-series. Models based on temporally aggregated data are useful because the data are available in real-time, allowing analysis of the health hazard within a few days. The researchers aggregated daily temperatures and mortality records from 147 regions in 16 European countries. They then analysed and compared the estimates of heat- and cold-related mortality by different levels of aggregation: daily, weekly, 2-weekly and monthly.

Analysis revealed differences in epidemiological estimates according to the time scale of aggregation. In particular, it was found that weekly, 2-weekly and monthly models underestimated the effects of heat and cold as compared to the daily model, and that the degree of underestimation increased with the length of the aggregation period. Specifically, for the period 1998–2004, the daily model estimated an annual cold and heat-related mortality of 290 104 and 39 434 premature deaths, respectively, while the weekly model underestimated these numbers by 8.56% and 21.56%, respectively.

“It is important to note that the differences were very small during periods of extreme cold and heat, such as the summer of 2003, when the underestimation by the weekly data model was only 4.62%,” explains Joan Ballester Claramunt, the ISGlobal researcher who leads the European Research Council’s EARLY-ADAPT project.

The team used this theoretical framework to revise the mortality burden attributed to the record temperatures experienced in 2022 in their earlier study. According to the calculations made using the new methodological approach, that study underestimated the heat-related mortality by 10.28%, which would mean that the actual heat-related mortality burden in 2022, estimated using the daily data model, was 70,066 deaths, and not 62,862 deaths as originally estimated.

Weekly data to analyse short-term effects of temperatures

“In general, we do not find models based on monthly aggregated data useful for estimating the short-term effects of ambient temperatures,” explains Ballester. “However, models based on weekly data do offer sufficient precision in mortality estimates to be useful in real-time practice in epidemiological surveillance and to inform public policies such as, for example, the activation of emergency plans for reducing the impact of heat waves and cold spells.”

It is an advantage in this area of research to be able to use weekly data since investigators often encounter bureaucratic obstacles that make it difficult or impossible to design large-scale epidemiological studies based on daily data. According to Ballester, when daily data is not available, the use of weekly data, which are easily accessible for Europe in real time, is a solution that can offer “a good approximation of the estimates obtained using the daily data model.”

Source: Barcelona Institute for Global Health (ISGlobal)

A New Intervention for Male Urinary Tract Symptoms

Urinary incontinence. Credit: Scientific Animations CC4.0

A new intervention for men with urinary problems trialled across GP practices has shown a sustained reduction in symptoms. Findings from the University of Bristol-led Treating Urinary Symptoms in Men in Primary Healthcare (TRIUMPH) study, involving over 1000 participants and 30 GP practices, have been published in the BMJ. The study was funded by the National Institute for Health and Care Research (NIHR).

The severity and prevalence of lower urinary tract symptoms [LUTS] in men increases with age (up to 30% in men over 65 years), with greater numbers likely to be affected as the population ages. Symptoms can have a substantial impact on quality of life but can also influenced by lifestyle factors.

Current therapies recommended by NICE (National Institute for Health and Care Excellence) include bladder training, controlling fluid intake and lifestyle advice. However, there is a lack of evidence on their effectiveness, and provision by GP practices varies.

Bristol Medical School researchers sought to trial whether a new intervention, comprising a healthcare professional consultation and an information booklet providing conservative and lifestyle guidance, could be more effective than usual care.

Study findings

The team recruited 1077 adult men, each suffering with troublesome urinary tract symptoms between June 2018 and August 2019. Participants were split with 524 in the intervention arm and 553 in the usual care arm. Participants in the intervention arm were directed to relevant sections of the booklet by general practice nurses/healthcare assistants or research nurses following urinary symptom assessment, with subsequent contacts over 12 weeks to ask how the participant was managing.

Overall, the study’s findings showed a range of troublesome urinary tract symptoms improved over 12 months in a population of men with moderate symptom severity, using a standardised booklet and manualised approach to symptom management. Analyses of symptoms in each trial arm found the intervention achieved a greater reduction in symptoms than usual care, and that the difference was maintained in the longer term

Consultant Urologist, Professor Marcus Drake, the study’s Chief Investigator, said: “The assessment of male lower urinary tract symptoms and use of conservative treatments in primary care are inconsistent. Until now, there was limited evidence that conservative treatments are effective, despite their recommendation in national guidelines. The TRIUMPH study aimed to address this need in primary care.

“Implementation of this intervention as management in primary care, has the potential to improve care and reduce drug prescriptions. Our study also found the intervention can be delivered by practice nurses or healthcare assistants rather than GPs.”

Dr Jon Rees, GP Partner at Tyntesfield Medical Group, and Chair of the Primary Care Urology Society, added: “In primary care we have often traditionally relied upon pharmaceutical management for men with bothersome urinary symptoms – the TRIUMPH study emphasises the importance of discussing conservative measures with all of these patients – for some men, this will be all that is required, for others these measures can act as an adjunct to any medication prescribed.

“Many men will prefer to avoid long-term medication, so an understanding of the potential benefits of the interventions used in the study is a vital part of the toolkit for any clinician managing these patients.”

Professor Matthew Ridd, at University of Bristol, said: “This is a ‘bread-and-butter’ problem seen by GPs every day and it is great to now have evidence for something other than tablets. It has the additional advantage that it can be done by a practice nurse, freeing up GP time.”

Source: University of Bristol

Ultra-processed Foods Linked to Mouth, Throat and Oesophagus Cancer Risk

Photo by Patrick Fore on Unsplash

Eating more ultra-processed foods (UPFs) may be associated with a higher risk of developing cancers of the upper aerodigestive tract (ie, the mouth, throat and oesophagus), according to a new study in the European Journal of Nutrition. The authors of this study, led by the University of Bristol and the International Agency for Research on Cancer (IARC), say that obesity associated with the consumption of UPFs may not be the only factor to blame.

Several studies have identified an association between UPF consumption and cancer, including a recent study which looked at the association between UPFs and 34 different cancers in the largest cohort study in Europe, the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, which followed 450 111 adults who for approximately 14 years.

As more evidence emerges about the associations between eating UPFs and adverse health outcomes, researchers from the Bristol Medical School and IARC wanted to explore this further.

Since many UPFs have an unhealthy nutritional profile, the team sought to establish whether the association between UPF consumption and head and neck cancer and oesophageal adenocarcinoma in EPIC could be explained by an increase in body fat.

Results from the team’s analyses showed that eating 10% more UPFs is associated with a 23% higher risk of head and neck cancer and a 24% higher risk of oesophageal adenocarcinoma in EPIC.

Increased body fat only explained a small proportion of the statistical association between UPF consumption and the risk of these upper-aerodigestive tract cancers.

Fernanda Morales-Berstein, a Wellcome Trust PhD student at the University of Bristol and the study’s lead author, explained: “UPFs have been associated with excess weight and increased body fat in several observational studies. This makes sense, as they are generally tasty, convenient and cheap, favouring the consumption of large portions and an excessive number of calories. However, it was interesting that in our study the link between eating UPFs and upper-aerodigestive tract cancer didn’t seem to be greatly explained by body mass index and waist-to-hip ratio.”

The authors suggest that other mechanisms could explain the association.

For example, additives including emulsifiers and artificial sweeteners which have been previously associated with disease risk, and contaminants from food packaging and the manufacturing process, may partly explain the link between UPF consumption and upper-aerodigestive tract cancer in this study.

Fernanda Morales-Berstein and colleagues did caution that the associations between UPF consumption and upper-aerodigestive tract cancers found in the study could be affected by certain types of bias.

This would explain why they found evidence of an association between higher UPF consumption and increased risk of accidental deaths, which is highly unlikely to be causal.

Inge Huybrechts, Team head of the Lifestyle exposures and interventions team at IARC, added: “Cohorts with long-term dietary follow-up intake assessments, considering also contemporary consumption habits, are needed to replicate these study’s findings, as the EPIC dietary data were collected in the 1990s, when the consumption of UPFs was still relatively low. As such associations may potentially be stronger in cohorts including recent dietary follow-up assessments.”

Further research is needed to identify other mechanisms, such as food additives and contaminants, which may explain the links observed.

However, based on the finding that body fat did not greatly explain the link between UPF consumption and upper-aerodigestive tract cancer risk in this study, Fernanda Morales-Berstein, suggested: “Focussing solely on weight loss treatment, such as semaglutide, is unlikely to greatly contribute to the prevention of upper-aerodigestive tract cancers related to eating UPFs.”

Source: University of Bristol

WHO Requests Information on Respiratory Illness Cluster in Northern China

The World Health Organization (WHO) noted an upsurge of unidentified pneumonia-like respiratory illnesses among children in Northern China, and asked China for more information. This is significant as previous outbreaks of severe respiratory illnesses have started out in this fashion, but such WHO requests for more information on disease clusters are routine as part of its monitoring. No “unusual or novel pathogens” have been found, according to China, which attributed it to an increase in multiple pathogens and the lifting of COVID restrictions.

Earlier this month, China’s National Health Commission reported a nationwide increase in respiratory disease incidence, mostly among children. This increase was attributed to lifting of COVID restrictions and the arrival of the cold season, and due to circulating known pathogens including Mycoplasma pneumonia and RSV, which are known to affect children more than adults.

On 22 November 2023, the WHO identified media and ProMED reports about clusters of undiagnosed pneumonia in children’s hospitals in Beijing, Liaoning and other places in China. The WHO requested from China additional epidemiologic and clinical information, as well as lab results from these cases and data about recent trends in circulating respiratory pathogens.

The WHO held a teleconference with Chinese health authorities and received data indicating an increase in outpatient consultations and hospital admissions of children due to Mycoplasma pneumoniae pneumonia since May, and RSV, adenovirus and influenza virus since October. Some of these increases are earlier in the season than usual, but not unexpected given the lifting of COVID restrictions, as similarly experienced in other countries. No changes in the disease presentation were reported by the Chinese health authorities, who said no unusual or novel pathogens or unusual clinical presentations had been detected, but only the general increase in respiratory illnesses by known pathogens. Local hospitals had not been overloaded by new cases.

Risk assessment

In the current outbreak of respiratory illness, the reported symptoms are common to several respiratory diseases and, as of now, at the present time, Chinese surveillance and hospital systems report that the clinical manifestations are caused by known pathogens in circulation. M. pneumoniae is a common respiratory pathogen and a common cause of paediatric pneumonia, and is readily treated with antibiotics.

China has stepped up its influenza-like illness (ILI) and severe acute respiratory infections (SARI) sentinel surveillance system since mid-October, including for M. pneumoniae.

There is limited detailed information available to fully characterize the overall risk of these reported cases of respiratory illness in children. However, due to the arrival of the winter season, the increasing trend in respiratory illnesses is expected; co-circulation of respiratory viruses may increase burden on health care facilities.

According to surveillance data reported to WHO’s FluNet and published by the National Influenza Centre in China, ILI was above usual levels for this time of year and increasing in the northern provinces. Influenza detections were predominantly A(H3N2) and B/Victoria lineage viruses.

WHO advice

The WHO advice was for people in China to take measures against respiratory illnesses, including vaccines, masking and social distancing. It also does not recommend any specific measures for travellers to China.

Source: WHO