Tag: public health

Healthy Diets Reduce COVID Risk

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A study based on self-reported app data showed that people who eat a high quality, gut friendly diet are less likely to develop COVID-19 or become severely ill. Those eating poorer quality diets are more at risk, especially if they live in a more socioeconomically deprived area.

The study, presented in GUT, analysed data from almost 600 000 ZOE COVID Study app contributors. Participants completed a survey about the food they ate before the pandemic, in February 2020, making it the largest study in this space. 19% of these contributors contracted COVID-19.

People with the highest quality diet were around 10% less likely to develop COVID than those with the lowest quality diet, and 40% less likely to fall severely ill.

This is the first longitudinal study of diet and COVID and the first to show that a healthy diet cuts the chances of developing the disease in the first place.

Instead of looking at specific foods, the survey aimed to broadly capture people’s diets. A ‘diet quality score’ reflected the overall merit of each person’s diet. Diets with high quality scores were found to contain plant-based foods such as fruits, vegetables and whole grains, as well as oily fish, less processed foods and refined carbohydrates. A low diet quality score is associated with diets high in ultra processed foods and low amounts of plant based foods.

The researchers found that people who ate the highest quality diet were around 10% less likely to develop COVID-19 than those with the least nutritious diet and 40% less likely to become severely ill if they developed COVID.

The link between diet quality and COVID risk persisted after accounting for all potential confounding factors such as age and BMI. Mask-wearing habits and population density were also considered.

The effect of diet was amplified by individual life situations, with people living in low-income neighbourhoods with the lowest quality diet being around 25% more at risk from COVID than people in more affluent communities eating the same kind of diet.

Based on these results, the researchers estimate that nearly a quarter of COVID cases could have been prevented if these differences in diet quality and socioeconomic status had not existed. The study also showed that improved access to better food is an important public health consideration.

Dr Sarah Berry, study co-lead and Reader in nutritional sciences at the School of Life Course Sciences said: “For the first time we’ve been able to show that a healthier diet can cut the chances of developing COVID, especially for people living in the more deprived areas. Access to healthier food is important to everyone in society, but our findings tell us that helping those living in more deprived areas to eat more healthily could have the biggest public health benefits.”

Professor Tim Spector, professor of genetic epidemiology at the School of Life Course Sciences, said: “These findings chime with recent results from our landmark PREDICT study, showing that people who eat higher quality diets (with low levels of ultra-processed foods) have a healthier collection of microbes in their guts, which is linked to better health. You don’t have to go vegan, but getting more diverse plants on your plate is a great way to boost the health of your gut microbiome, improve your immunity and overall health, and potentially reduce your risk from COVID.”

Source: Kings College London

Supermarket Layout Change Encourages Healthy Food Purchases

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A study into food purchasing behaviours shows that placing fruit and vegetables near store entrances and removing confectionery and other unhealthy products from checkouts and the end of nearby aisles prompts customers to make healthier food purchases.

The study, led by Dr Christina Vogel, Principal Research Fellow in Public Health Nutrition and Janis Baird, Professor of Public Health and Epidemiology at the University’s MRC Lifecourse Epidemiology Centre, was conducted in partnership with the national supermarket chain Iceland Foods Ltd. The trial took place in a number of Iceland stores in England, monitoring store sales as well as dietary patterns of sample customers.

The results showed confectionery sales decreased throughout the store while fruit and vegetable sales increased when non-food items and water were placed at checkouts and at the end of the opposite aisles, and an expanded fruit and vegetable section was repositioned near the store entrance. Beneficial effects were also observed for household fruit and vegetable purchasing and individual dietary quality. The findings are presented in the open-access journal PLOS Medicine.

Discussing the results of the study Dr Vogel said “Altering the layouts of supermarkets could help people make healthier food choices and shift population diet towards the government’s dietary recommendations. The findings of our study suggest that a healthier store layout could lead to nearly 10 000 extra portions of fruit and vegetables and approximately 1500 fewer portions of confectionery being sold on a weekly basis in each store.”

This research is more comprehensive than previous studies testing whether placement strategies can promote healthier food purchasing which have been limited in scope, for example including only a single location (ie at checkouts) or placing healthy and unhealthy products together. This study further aimed to reduce exposure of customers to calorie opportunities by placing non-food items at checkout and aisle-ends opposite and measuring effects on store sales, purchasing patterns on customer loyalty cards and the diets of more than one household member.

Matt Downes, Head of Format Development at Iceland, said:   “We have been pleased to support this long-term study and the evaluation of how product placement in supermarkets can affect the diets of our customers. We know that childhood obesity is a growing issue and the retail industry has its part to play in tackling this. We hope that the outcomes of the study provide insights for the wider retail industry and policy makers about the impact of store merchandising on purchasing decisions.”

Prof Baird added “These results provide novel evidence to suggest that the intended UK government ban on prominent placement of unhealthy foods across retail outlets could be beneficial for population diet, and that effects may be further enhanced if requirements for a produce section near supermarket entrances were incorporated into the regulation.”

Source: University of Southampton

Low-level Air Pollution Still Linked to Higher Mortality

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Long-term exposure to air pollution appears to still be linked to higher mortality despite the existence of air quality standards that restrict levels of pollution, suggests a study published online in The BMJ today.

Previous studies have found an association between long term exposure to outdoor air pollution such as those in the form of fine particles in the air (known as particulate matter or PM2.5) and nitrogen dioxide (NO2) and illness or mortality.

While air pollution concentrations have fallen substantially in Europe since the 1990s, it is unclear whether there still is a link between pollution and ill health or death at pollution levels under permitted levels.

Therefore, researchers set out to determine if there was an association between low levels of air pollution concentrations and natural and cause-specific deaths.

Low-level air pollution was defined as concentrations below current limits set by the European Union, US Environmental Protection Agency and the World Health Organization (WHO).

The researchers analysed data on eight groups of people within six European countries. Their study recruited participants in the 1990s or 2000s. Of the 325 367 participants who were followed up over an almost 20-year period, around 14.5% (47 131 people) died during the study period.

An increase of 5 µg/m3 (a concentration measure of particulate matter) in particulate matter (PM2.5) was associated with a 13% increase in natural deaths while the corresponding figure for a 10 µg/m3 increase in nitrogen dioxide was 8.6%. Associations with PM2.5 and NO2 were largely independent of each other.

Moreover, even at low to very low concentrations, associations with PM2.5, NO2, and black carbon remained significant. For people exposed to pollution levels below the US standard of 12 µg/m3, an increase of 5 µg/m3 in PM2.5 was associated with a 29.6% increase in natural deaths. People exposed to NO2at less than half the current EU standard of 40 µg/m3, a 10 µg/m3 increase in NO2 was associated with a 9.9% increase in natural deaths.

The study also has some limitations, the researchers said, such as the fact that it focused on exposure in 2010 which was towards the end of the follow-up period for most participants and, given falling air pollution, this measure might not exactly reflect the concentrations experienced during follow-up.

However, this was a large study from multiple European groups of people with detailed information provided. As such, the authors concluded: “Our study contributes to the evidence that outdoor air pollution is associated with mortality even at levels below the current European and North American standards and WHO guideline values.

“These findings are therefore an important contribution to the debate about revision of air quality limits, guidelines and standards, and future assessments by the Global Burden of Disease [study].”

Source: The BMJ

August Poll Results; 18-34s Upbeat on Vaccines

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To date, nearly 12 600 000 vaccinations have been administered in South Africa, with 23.66% of the adult population now fully vaccinated. Quicknews’ August poll revealed that 44% of site visitors felt that the government’s COVID vaccine rollout was “Acceptable”, while 51% felt it was either “Poor” or “Very Poor”. Only 5% rated it “Good” or “Very Good”.

The Department of Health’s COVID-19 and Vaccine Social Listening Report finds that the demand for vaccination had increased, with around 250 000 daily jabs, fuelled by a surge by the recent eligibility of the 18 – 34 age group. The report highlights include:

  • Social media conversations are more positive about the vaccine rollout with improved services, such as free transport and pop-up vaccination sites. Barriers to vaccination seem now to be more of an issue than vaccine hesitancy. It is noticeable that most anti-vax videos originated from other countries (especially the US), while most pro-vax are local (eg celebrating being vaccinated).
  • While vaccination is met with eagerness and discussion among the 18 – 34 age group, they also still appear to be the most vaccine-resistant age group, believing themselves to be healthy and not needing a vaccine. Discussion over whether vaccines should be mandatory is ongoing, eg to go to concerts, with some disinformation suggesting that it is already happening, and a sign of control by the state.
  • There has been increasing media coverage supportive to vaccines. The Department of Health’s vaccine demand acceleration plan has been met positively, as well as favourable coverage of the FDA’s full approval of the Pfizer vaccine. 
  • However, there are some negative views of the government’s vaccine prioritisation, and is seen as neglecting basic services such as sanitation and public transport. 
  • A WhatsApp survey run by Praekelt.org suggests that 90% of 4,000 people who had been vaccinated are willing to encourage others to do so. People reportedly have more rational concerns about vaccines (efficacy, side effects, developed so quickly, reports of deaths) and not the wilder conspiracy theories (eg tracking devices, depopulation).
  • Disinformation and problematic statements such as those from Rev Kenneth Meshoe vaccine-resistant statements and support for anti-vaxxers Dr Susan Vosloo and Prof Tim Noakes have undermined vaccine trust.
  • There is some debate over preferences over currently available vaccines or those that may be available later, eg Astra Zeneca, Sinovac. Confusion on reports that J&J second dose might be required and other booster shots.
  • The report notes some anti-vaccination sentiment in the Muslim community, with messages circulated that vaccines are haram (forbidden by Sharia law), though most Muslim authorities produce responsible evidence-based views.

Source: SA Coronavirus Portal

Added Potassium Salt Substitute Greatly Cuts CVD Risk

Source: Pixabay CC0

Replacing table salt with a low-sodium, added potassium ‘salt substitute’ significantly reduces rates of stroke, heart attack and death, one of the largest dietary intervention studies ever conducted.

Presented at the European Society of Cardiology Congress in Paris, and simultaneously published in the New England Journal of Medicine, the results also showed that there were no harmful effects from the salt substitute, such as hyperkalaemia.

High sodium intake and low potassium intake are widespread. Both are linked to hypertension and increased risks of stroke, heart disease and premature death. Using a salt substitute – where part of the sodium chloride is replaced with potassium chloride – addresses both problems at once. Salt substitutes are known to lower blood pressure but their effects on heart disease, stroke, and death were unclear, until now.

Lead researcher, Professor Bruce Neal of The George Institute for Global Health, said that the benefit could prevent millions of early deaths with the widespread adoption of salt substitutes.

“Almost everyone in the world eats more salt than they should.  Switching to a salt substitute is something that everyone could do if salt substitutes were on the supermarket shelves,’’ he said.

“Better still, while salt substitutes are a bit more expensive than regular salt, they’re still very low-cost – just a few dollars a year to make the switch.”

“As well as showing clear benefits for important health outcomes, our study also allays concerns about possible risks.  We saw no indication of any harm from the added potassium in the salt substitute.  Certainly, patients with serious kidney disease should not use salt substitutes, but they need to keep away from regular salt as well,” added Professor Neal.

The Salt Substitute and Stroke Study enrolled 21 000 adults with either a history of stroke or poorly controlled blood pressure from 600 villages in rural areas of China from 2014 to 2015.

Participants in intervention villages were provided enough salt substitute to cover all household cooking and food preservation requirements – a daily amount of 20g per person. Those in the other villages continued using regular salt.

Over five years’ average follow up, more than 3000 participants had a stroke. Use of salt substitute reduced stroke risk by 14 percent, total cardiovascular events (strokes and heart attacks combined) by 13 percent and premature death by 12 percent.

Professor Neal said that as salt substitutes are relatively cheap (US$1.62 per kg vs US$1.08 per kg for regular salt in China), they are likely very cost effective.

“Last year, a modelling study done for China suggested that about 400 000 premature deaths might be prevented each year by national uptake of salt substitute. Our results now confirm this. If salt was switched for salt substitute worldwide, there would be several million premature deaths prevented every year,” he said.    

“This is quite simply the single most worthwhile piece of research I’ve ever been involved with. Switching table salt to salt substitute is a highly feasible and low-cost opportunity to have a massive global health benefit.”

As a result of the study, George Institute researchers are calling for salt manufacturers to embrace salt substitution, the promotion of salt substitutes by governments, and the use of substitute salt by consumers.

Source: George Institute for Global Health

Govt Switches COVID Focus to Vaccine Access and Hesitancy

Image by Quicknews

As the official COVID death toll in South Africa passes the 80 000 mark, the Department of Health is now shifting focus to addressing flagging vaccine demand.

The department said this will include making access easier, such as vaccinating at shops or places of work.

Another change would be providing transportation to vaccine sites to help those in underprivileged areas. One option being looked into is the introduction of home vaccinations and ‘pop-up’ sites in rural areas where travel is harder to come by and at busy commercial areas such as shopping centres.

The government also hopes for assistance from the religious sector, with the possibility of churches offering vaccines on a Sunday. Mosques, synagogues and other places of worship would also offer a ‘familiar environment’ where people feel comfortable receiving a vaccine.

Public awareness
Social media will be heavily employed for vaccine promotion, and could incude online influencers and ambassadors to encourage vaccination.
This could extend to identifying ‘apolitical’ vaccine champions relevant to the target group who have also great influence, such as celebrities and traditional leaders.

A number of awareness initiatives are being considered, including making use of channels such as social media and teachers to provide information to young people and counteract misinformation, as well as more traditional media efforts such as radio slots and signage.

Vaccine skepticism high in men
Department of Health Deputy director-general Dr Nicholas Crisp, pointed out that South Africa has a particular problem with men not wanting to be vaccinated.

“This is not good,” Dr Crisp said. “It means that men are going to end up very sick and in hospital, and we don’t want that to happen just before Christmas.”

An Africa Centres for Disease Control and Prevention (ACDC) study found that 66% of men in South Africa were sceptical about vaccine safety compared to 74% of women.

Mandatory vaccinations on the cards
Health minister Dr Joe Phaahla warned of a very long road ahead as new cases continue to spike.

The ministerial advisory committee on COVID is now discussing the possibility of mandatory vaccination for certain groups of people, which could include healthcare workers and those professions spending time indoors with other people, according to the Sunday Times.

Scientists and health activists told the paper that the right to refuse a vaccine is outweighed by the health hazard of the pandemic.

The country would then be able to reopen and operate in a way as close as possible to the pre-COVID era, said leading vaccinologist Professor Shabir Madhi.

“In these settings, if people choose not to be vaccinated, they should be compelled to undergo testing every three or four days at their own expense,” he said.

While vaccinations don’t confer complete COVID protection, it is still significant, and more impactful if a greater proportion are vaccinated, Prof Madhi said.

Source: BusinessTech

Another COVID-scale Pandemic in 59 Years ‘Statistically Likely’

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A new study based on 400 years of historical records asserts that extreme pandemic events such as COVID are more common than believed.

The Duke University study, published in Proceedings of the National Academy of Sciences, used records of past outbreaks to estimate the intensity of those events and the yearly probability of them recurring.

It found the probability of a pandemic with similar impact to COVID is about 2% in any year, meaning that someone born in the year 2000 by now would have about a 38% chance of experiencing one. That probability is only increasing, highlighting the need to adjust perceptions of pandemic risks and expectations for preparedness, the researchers said.

“The most important takeaway is that large pandemics like COVID and the Spanish flu are relatively likely,” said study co-author William Pan, PhD, associate professor of global environmental health at Duke. The understanding that pandemics are not so rare should raise the priority of future prevention and control efforts, he said.

The study employed new statistical methods to measure the scale and frequency of disease outbreaks for which there was no immediate medical intervention over the past four centuries. Their analysis, including deadly pathogens including plague, smallpox, cholera, typhus and novel influenza viruses, found pandemics occurred with great variability in the past. But they also identified patterns that allowed them to describe the probabilities of similar-scale events happening again.

In the case of a pandemic like the Spanish flu, which killed more than 30 million people between 1918 and 1920, the probability of a pandemic of similar magnitude occurring ranged from 0.3% to 1.9% per year over the time period studied. Taken together, it is statistically likely that such a massive pandemic would occur within the next 400 years.

However, the data also show that the risk of intense outbreaks is increasing rapidly. Based on the increasing rate at which novel pathogens such as SARS-CoV-2 have broken loose in human populations in the past 50 years, the study estimates that the probability of novel disease outbreaks will likely triple in the next few decades.

With this increased risk factor, the researchers estimate that a COVID-scale pandemic is likely within a span of 59 years (by the year 2090), a result they write is “much lower than intuitively expected.” Although not included in the paper, they also calculated the probability of a pandemic capable of eliminating all human life, finding it statistically likely within the next 12 000 years. 

That does not mean it will be 59 years before the next COVID-like pandemic, nor that the Spanish flu for another 300 years. Such events are equally probable in any year during the span, said Duke University Professor Gabriel Katul, another of the paper’s authors.

“When a 100-year flood occurs today, one may erroneously presume that one can afford to wait another 100 years before experiencing another such event. This impression is false. One can get another 100-year flood the next year,” explained Prof Katul.

Dr Pan noted that population growth, changes in food systems, environmental degradation and more frequent contact between humans and disease-harboring animals all may be significant factors for increasing frequency of pandemics. However, he stresses that the statistical techniques are not to explain the pandemics.

However, he hopes the study will spark deeper exploration of the factors that may be making devastating pandemics more likely – and how to counteract them.

“This points to the importance of early response to disease outbreaks and building capacity for pandemic surveillance at the local and global scales, as well as for setting a research agenda for understanding why large outbreaks are becoming more common,” Dr Pan said.

Source: Duke University

Cervical Cancer Rates Falling Worldwide

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Cervical cancer incidence and mortality rates are holding steady or falling in most countries across the globe, according to a new analysis. Each country’s socioeconomic development level, cervical cancer screening use, and human papillomavirus (HPV) vaccination rates affect the rates. The findings are published online in CANCER.

Cervical cancer can be potentially prevented through screening for and treatment of precancerous lesions and through HPV vaccination. A team led by Mingjuan Jin, PhD, of the Zhejiang University School of Medicine in China, examined information on 31 countries released by the International Agency for Research on Cancer.

The analysis found that cervical cancer incidence and mortality rates were lower in more socioeconomically developed countries. Also, both past and predicted trends appear to be stable or decreasing in most countries, especially in those with effective cervical cancer screening and HPV vaccination programs.

Over the past decade, 12 countries had stable cervical cancer incidence rates, while rates fell in 14 and rose in five. Twelve countries had stable mortality rates from cervical cancer, with falling rates in 18 and only one had an increased rate.

The researchers predicted that for 27 countries, most are expected to have stable or decreasing trends over the next 15 years. Ten of the 27 countries are predicted to have stable incidence rates, nine to have decreasing rates, and eight to have increasing rates. Mortality rates are predicted to be stable in 16, decreasing in 10 and one to have an increasing rate.

“Effective cervical cancer screening programs and HPV vaccination should be further popularized to increase their coverage and ultimately decrease cervical cancer’s short-, mid-, and long-term burden,” said Dr Jin.

Source: Wiley Online

Attaining Herd Immunity for COVID Now Unlikely

Image by Quicknews

In an article published in the South African Medical Journal, Shabir Madhi, Professor of Vaccinology at Wits, argues that COVID variants have made the initial goal of attaining herd immunity no longer feasible, even for well-resourced countries. However, vaccine protection against severe COVID seems a more realistic path to normalcy.

In low and middle income countries (LMICs), the official COVID case estimates are likely grossly underestimated, Prof Madhi writes, due to a lack of testing coverage. Even in South Africa, the true number of COVID cases is likely in the region of 10 times the 2.39 million recorded through testing. The true number of COVID-related deaths in India is also estimated as 3.4–3.9 million, again 10 times the official count, and in South Africa it is likely three times the official  figure of 70 388 in July 2021.

While New Zealand researchers have suggested that COVID eradication is feasible, it is likely a very long term goal if at all attainable. The herd immunity goal can be considered with the equation (p1 = 1 – 1/R0), where p1 is the proportion of immune individuals who will also no longer transmit the virus, and R0 is the reproduction rate, ie the number of susceptible individuals a single infected person can further infect. However, this ignores key aspects of the virus.

The problem is that the proportion of people that would need to be immunised to achieve herd immunity was initially calculated at 67%, based on an assumed R0 of 3, derived from the Wuhan strain’s R0 of 2.5 to 4. However, the Delta variant has an R0 of 6, meaning that to reach herd immunity, 84% of the population would need to be vaccinated. In South Africa, this would be 100% of the population aged over 12.

The emergence of SARS-CoV-2 variants, especially the Beta variant with the E484K mutation, showed that existing vaccine protection, including the Pfizer variant, can be degraded to an extent.

Studies have strongly suggested that neutralising and antibody titers are associated with mild to moderate COVID protection, while protection from severe COVID may be mediated by T-cell immunity.

Real world data showed that in Israel, with a world best immunisation of 61.6% using the Pfizer vaccine which produces the greatest antibody response, herd immunity appeared to be successful until an outbreak of the more transmissible Delta variant combined with waning vaccine effectiveness. 

However, in the UK, excess death data showed that, even with a resurgence of cases caused by the Delta variant, there was a significant decoupling of deaths from cases. This points to the effectiveness of vaccines in preventing severe illness, as opposed to reaching herd immunity.

Vaccine rollouts have therefore not interrupted COVID transmission. Prof Madhi concludes that, based on an estimated R0 of 6 for the Delta variant, “it is unlikely that any country could have a sustainable strategy for durable high level of protection against infection by the delta variant. Mutations of the SARS-CoV-2 genome are likely to continue resulting in enhanced transmissibility, infectiousness and resistance to neutralising activity.”

He observes that the “UK approach seemingly concedes that the goal of herd immunity, even in a highly resourced setting, is unattainable.”

He adds that aspiring to reach herd immunity by wealthy countries comes at the cost of exacerbating vaccine inequality, which he says “is immoral.”
Antibody dynamics modelling suggests that a booster would be required every 2–3 years to protect against severe COVID, and every 6–9 months to protect against moderate disease. This is a challenging goal, and likely unattainable for most LMICs, especially given the slow rate of vaccination in those settings.

Source: South African Medical Journal

A Look Back at Mkhize’s Tenure as Health Minister

Image by Hush Naidoo from Unsplash
Image by Hush Naidoo from Unsplash

With Dr Joseph Phaahla being promoted from his position as Deputy Health Minister to replace the embattle, Dr Zweli Mkhize, Spotlight reviews Dr Mkhize’s tenure, writing that the very reason he was brought in to that post — to roll out National Health Insurance — would likely suffer a considerable setback as a result of his exit.

His appointment as South Africa’s Minister of Health in May 2019 came as a surprise for some. As one of the ANC’s top officials, the health portfolio seemed a meagre choice in the pre-COVID days.

However, Mkhize’s seniority signalled that health was being given high priority in the new administration. Theoretically, his greater political clout meant he would have a better chance of bringing much-needed reforms to provincial healthcare systems. Spotlight were also “cautiously hopeful that Mkhize’s firmer hand would help better organise and direct the National Health Department and the various national health entities.”

A string of procurement scandals during his time as KwaZulu-Natal’s Premier was cause for concern but was not direct evidence that he was corrupt.

The Digital Vibes scandal had the side effect of making Mkhize anathema to the very project he was originally brought in for, implementing National Health Insurance.

Even with Mkhize gone, the ANC will have a hard time convincing the public that we will not see more such looting once NHI is implemented. There has, after all, been little willingness from ANC members in Parliament to engage seriously with people’s concerns about the proposed NHI structure and governance arrangements set out in the NHI Bill.

Mkhize tackled COVID from a scientific standpoint, which is fortunate for the nation considering the anti-scientific stance of the former Minister of Health Dr Manto Tshabalala-Msimang. However, the decision not to use AstraZeneca vaccines remains contentious. Meanwhile, a purge of scientists, starting with Professor Glenda Gray, let Mkhize surround himself with allies, according to Spotlight.

However, entering the third wave with vaccinations lagging so far behind was a governance disaster possibly even worse than the Digital Vibes scandal.

From an outside perspective, the past two years have not seen great progress in the department, despite some competent individuals, with infighting, under-capacity and most seriously, poor management. The procurement department

Source: Spotlight