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Why Flu Vaccines Don’t Work as Well in the Elderly





Flu Shot

The flu vaccine isn’t as effective in older populations. A new study has found B-cell changes as we age may be to blame. (Credit: JPC-PROD /

The adage that “the older you are, the wiser you get” doesn’t always apply to our immune systems. Despite being exposed to a lifetime’s worth of illnesses, immune systems in the elderly are worse at fighting stealthy, shape-shifting viruses like the flu.

Why aging decreases our immune system’s abilities has been a mystery to researchers. But a new study published in Cell Host & Microbe finds that our infection-battling B-cells become blunted with age, making us less equipped to fight off the flu and other illnesses in our advanced years. And because most vaccines rely on a B-cell response to work, the finding may explain why the influenza vaccine is less effective in this population.

New Mutations, Old Tools

A research team compared how B-cells and antibodies from younger adults (ages 22 to 64) and elderly adults (ages 71 to 89) responded to vaccines for recent flu strains. The B-cells of younger people were good at recognizing mutations of the virus and producing protective antibodies. But the older people’s B-cells were less adept at fighting the rapidly changing influenza virus. Their B-cells were stagnant and the antibodies they produced were less diverse and less potent than the younger people’s.

“[Their B-cells] are ‘stuck in the past.’ The influenza viruses mutate and evolve with time, but with age, our B-cells can no longer keep up,” said senior study author Patrick Wilson, a researcher at the University of Chicago. “They don’t have quite the right tool to fight it.”

Our immune systems learn from exposure, and B-cells play a major role in the immunity process. With the help of other cells in the immune system, B-cells churn out antibodies when we get sick or receive an immunization. Antibodies are Y-shaped proteins that bind to harmful invaders and mark them for destruction. Once the infection is cleared, a type of record-keeping B-cell, known as memory B-cells, remain in the bloodstream and stand ready to produce antibodies if the threat is encountered again.

As we age, something hampers our immune system’s ability to produce ever-stronger antibodies in response to infections. As a result, older people are relying on mostly memory B-cells to make antibodies from long-past immune responses that are ill-equipped to squash rapidly evolving pathogens like the flu virus.

Immune Imprinting

While new flu strains threw the elderly participant’s B-cells for a loop, they were very proficient at combatting mutations of the virus that circulated during their childhoods. Young people’s B-cells, however, struggled when faced with older strains of the flu.

Although each person’s timeline is different, the strength of our immune response diminishes over time once we hit a certain age. The researchers observed that participants between 50 and 70-years-old had intermediate declines in their influenza-fighting power, with steeper drops typical after age 70.

That’s why vaccines are so necessary for the elderly. But because the ever-changing flu virus is capable of outsmarting young and old immune systems alike, even a well-matched vaccine may only reduce the chances of illness by 40 to 60 percent in the general population. Effective rates are typically less for the elderly, but Wilson stressed that “not as effective” does not mean “not at all effective.”

“Vaccination still helps even if not as effective with age,” he said. “With vaccination, the duration and severity of illness will be reduced, which is extremely important for older people as the severity of infection is already much worse.”

As the research community toils toward a universal flu vaccine that would provide lifetime immunity, there have been advancements in the interim. New high-dose flu vaccines for older adults are now available and can unleash more protective antibodies.


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Globe Climate: Canada’s resource reckoning is coming





Good afternoon, and welcome to Globe Climate, a newsletter about climate change, environment and resources in Canada.

This afternoon, the Alberta government announced that it is restoring a coal mining policy it revoked last spring. At the time, the move provoked a widespread public backlash detailed by The Globe. The original decision, which opened up more than 1.4 million hectares to exploration, was made without public consultation. Premier Jason Kenney previously defended the changes.

Lots more on coal and Canada’s resources industry in this week’s newsletter edition.

Now, let’s catch you up on other news.

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‘Incredibly destructive’: Canada’s Prairies to see devastating impact of climate change





As the climate continues to warm at an alarming rate, experts warn if dramatic steps to mitigate global warming are not taken, the effects in Canada’s Prairie region will be devastating to the country’s agriculture sector.

According to Environment and Climate Change Canada, the country is warming, on average, about double the global rate.

Scientists with the National Oceanic and Atmospheric Administration in the U.S. recently found 2020 was earth’s second-hottest year on record, with the average land and ocean surface temperature across the globe at 0.98 of a degree C above the 20th-century average.

However, the agency found the northern hemisphere saw its hottest year on record, at 1.28 degrees C above the average.

“(In Canada) we are looking at about 6.4C degrees of warming this century, which isn’t much less than one degree per decade, which is just a terrifying rate of warming,” Darrin Qualman, the director of climate crisis policy and action at the National Farmer’s Union said.

Qualman said there is “massive change coming” to Canada’s Prairies, which will be “incredibly destructive.”

“It’s not going too far to say that if we made that happen, parts of the Prairies wouldn’t be farmable anymore,” he said.

According to the federal government, in 2018 Canada’s agriculture and agri-food system generated $143 billion, accounting for 7.4 per cent of the country’s GDP.

The sector employed 2.3 million people in 2018. The majority of the 64.2 million hectares of farmland in Canada is concentrated in the Prairies and in southern Ontario.

The effects of climate change are already being felt on the ground in the Prairies, Qualman said, adding that the NFU has already heard from farmers complaining of “challenging weather.”

“People are sharing pictures of flattened crops and buildings, et cetera, that have been damaged,” he said. “And we’re still at the beginning of this.”

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Insect-based dog food aims to cut your pet’s carbon pawprint





Meat has an enormous carbon footprint, with livestock liable for about 15 per cent of worldwide emissions, as we have beforehand mentioned on this e-newsletter. That is prompted specialists to suggest consuming much less meat for sustainability (and well being) causes.

However what about your pet? One research discovered that the methane and nitrous oxide emissions generated by canine and cat meals within the U.S. alone had been equal to about 64 million tonnes of CO2, or roughly the quantity produced by 13.6 million automobiles. And it might be getting worse, with a development towards feeding pets “human-grade” meat.

That is prompted some pet meals makers to look to lower-carbon protein sources — together with bugs.

Research present that producing insect-based meals requires far much less feed, land and water and generates far fewer greenhouse fuel emissions per kilogram than meats comparable to beef, pork or rooster.

That is one of many causes increasingly more pet meals containing insect protein are hitting the market. Purina, a model owned by multinational Nestlé, launched a line of canine and cat meals containing black soldier fly larvae in Switzerland in November.

In Canada, Montreal-based Wilder Harrier began promoting canine treats made with cricket protein in 2015 and pet food made with black soldier fly larvae in 2019. It plans to broaden to launch a line of insect-based cat treats later this yr and cat meals in 2022 due to “a ton of demand,” mentioned firm co-founder Philippe Poirier.

Wilder Harrier initially labored with animal nutritionists on insect-based merchandise to unravel a unique downside — specifically, the founders’ canines had allergy symptoms to frequent meats utilized in canine meals. Poirier mentioned now about half its prospects hunt down the product due to their pets’ allergy symptoms and about half for environmental causes.

Dr. Cailin Heinze, a U.S.-based veterinary nutritionist licensed by the American School of Veterinary Vitamin, has written concerning the environmental influence of pet meals. She mentioned we’re typically “not as involved as we probably ought to [be]” concerning the environmental footprint of pets.

Alternatively, she famous that the longer-term influence of newer diets, comparable to vegan meals and people containing bugs, hasn’t been nicely examined in comparison with conventional pet meals.

Maria Cattai de Godoy, an assistant professor of animal sciences on the College of Illinois who research novel proteins for pet meals (together with bugs, yeast and plant-based substances), mentioned such substances are rigorously examined to find out their security and diet earlier than being added to pet meals. 

“This can be a very extremely regulated trade,” she mentioned, however admitted it is also evolving.

Relating to bugs, she mentioned constructive information “reveals promise in direction of utilizing them increasingly more in pet meals.” Insect-based proteins have additionally earned the endorsement of the British Veterinary Affiliation, which says some insect-based meals could also be higher for pets than prime steak.

However Godoy famous that there isn’t any one-size-fits-all resolution, and pet homeowners ought to take into consideration the wants of their very own particular person pet and analysis whether or not a specific weight loss plan can be appropriate.

She mentioned that other than the kind of protein, issues like packaging and manufacturing strategies may also make a distinction. For instance, utilizing meat byproducts that may in any other case turn into waste would not drive elevated meat manufacturing the identical approach as utilizing human-grade meat.

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