Cold truths from the world of virology

At the Research Matters Curiosity Shop people ask questions they’d like Ontario university researchers to answer. Recently, a visitor to the Shop asked: “Can we ever cure the common cold?” Research Matters tracked down Ana Sanchez, an infectious disease expert and instructor of medical microbiology at Brock University to get some answers.

Spoiler alert: It does not sound as though the facial tissue and cough medicine industries are in any danger.

Research Matters:    Why is it so hard to find a cure for the common cold?  
Ana Sanchez:    The first reason is because the disease is not caused by a single pathogen. There are more than 100 types of rhinoviruses that cause the symptoms we have come to know as the common cold. Then we have adenoviruses, coronaviruses and other groups that cause colds as well. Within each group, many variations can occur, providing different qualities to viruses, to which we must adapt and so our immune system can react appropriately . It would be a challenge to find a drug or vaccine that targets of them.

So, the diversity of the pathogens is, is the first challenge.

RM:     What else?
AS: Another challenge is that these viruses change a lot. They mutate. So even if we were to create a treatment it would be like a moving target.  It would be like the influenza, where we have to make new vaccines the time. Unless scientist find a special part of the virus molecule; a molecule that is common to an entire group and does not change much, the challenge will remain.

RM: Are viruses more challenging to treat than bacterial infections?
AS: For the longest time we were not able to create drugs to treat viral infections because scientists couldn’t identify a particular physiological aspect of a virus they could target. Bacteria are cells – living organisms with active metabolisms. They have membranes, cytoplasms, and nuclei we could decipher. We understand them better, which makes them easier to fight.

With viruses, we now know we’re not targeting live cells. Viruses are actually not “alive” although they carry a code for life. They don’t replicate by themselves, they don’t have metabolism.  They are the ultimate parasites and need to colonize a cell to do that, right?  So even when we may have drugs to inactivate viruses, because they live inside our cells, many time we end up damaging our own cells as well. As biotechnology advances, however, scientist are more able to conceive drugs or treatments to fight viruses off without causing too much damage to the patient.

Now, not viral infections are difficult to deal with. Some viruses, like hepatitis B are very stable, so it was possible to create a vaccine you can trust. It depends on the virus.

RM: Can scientists learn anything from the human immune system about curing colds?
AS: They could, but that’s really beside the fact. We get an infection, and our body successfully deals with it within a few days. We mount a strong cellular and antibody response and end up winning the battle.

But then we get another virus and another. There’s no end to the diversity of cold viruses.

RM: So, what’s the long-term prognosis for a cure?
AS: Curing the common cold is a terrible challenge. And remember that it is not really a severe disease. For most people, it is a nuisance. There’s a lot of people with the illness, but it’s not like influenza or other respiratory diseases that tend to be more serious. And even if there was a vaccine that worked for some cold viruses, it’s going to be hard to convince people that the vaccine works because they will get another cold from another virus and think, ‘Well this vaccine didn’t work well.’

RM: Is this just a never-ending battle, then?
AS: Each time there is a medical advance in virology – like the way we’re starting to better control HIV – we think we’re winning the battle against infectious agents. We have better drugs and people are living longer.  Then, boom, there’s something else.

Take Ebola. In the mid-1970s, Ebola became an issue for a period of time, and then we heard nothing for years. We thought maybe it was just a fluke. And then just comes back.

Of course, living a healthy life with good nutrition and good rest will improve your immune system to fight pathogens. And fighting pathogens (most of the time successfully) is something that we humans have been doing forever…

We are born with an immune system exactly because we need to fight these pathogens.  It’s there for a reason. But the other side is also always going to be there.

Tagged: Health, Stories

Share: Print

Leave Comments

Blog Posts

genetic barcodes

Barcoding life, one species ...

Sharon Oosthoek | May 2, 2016

Nobody knows for sure how many species exist. But scientists are certain we have identified only a fraction of the plants, animals and fungi on the planet — roughly 1.7 million species out of an estimated 10 to 20 million. "Most of the yet-to-be-identified species will be tinier life forms, but the numbers could even be larger," says University of Guelph biologist Paul Hebert. "That's just a best guess." Making an inventory of all life then would seem a Sisyphean task. But back in 2003, Hebert and his research team proposed a DNA tool for doing exactly that. At the same time, they made a convincing case for why we might want such an inventory: our species is accelerating the extinction rate of other species, and as Hebert puts it, "people take action when they know what is happening to life." Their argument was convincing enough to lead to the creation in 2010 of the International Barcode of Life (iBOL) project, an alliance representing 26 countries and headquartered at the University of Guelph.  Since then, affiliated researchers have collected from all over the world biological samples such as feathers, fur, blood and tiny bits of tissue. In 2015, they reached their goal inventorying half a million species. They have now set a ambitious target of identifying all species on the planet by 2040. As Hebert and his team originally envisioned, the tool the researchers are using to identify species is a short section of DNA from a standardized region of the genome, found in all living things. The sequence of the molecules that make up that chunk of DNA can be used to identify different species, in the same way a supermarket scanner uses the black stripes of the UPC barcode to identify purchases. As an added bonus, the DNA section is short enough to be sequenced quickly and cheaply, yet long enough to discriminate species. Fish out of water The tool has already been used to identify invasive species and the illegal sale of mislabelled endangered fish. While Hebert and his team are certainly on board with that, their ultimate vision has always been much loftier. "Each species is a book of life that describes how to reconstruct a robin or a blue jay or a monarch butterfly," says Hebert. "It's possible that by the end of the century, one-sixth of those books of life will not longer be with us. One of the objects of our work is to register all the species on the planet before they disappear." But this isn't just about creating an inventory. Rather it's about creating a digital Noah's ark. Along with the identifying section of DNA, the barcode project saves each species' entire genome — in other words, its complete set of DNA, representing instructions for building each species. That means the chemical pathways responsible for producing yet-to-be-discovered life-saving drugs will be preserved. "It's even possible that we might be able to reconstruct species," says Hebert. "Maybe humanity will decide it's sad living on a planet with few other species on it. It would be completely impossible to restore lost species if we don't have their DNA. "        

Creating community through cuisine

Emma Drake | April 27, 2016

Food is more than a meal; it can be intrinsic to a person’s identity. But for refugees, part of their identity is challenged when they settle in countries that don’t offer foods from home. “We share culture and richness through food,” says Valencia Gaspard, a PhD student in rural studies at the University of Guelph. “Food can be used to build communities and bring people together.” Valencia is part of a team of student studying the availability of ethnocultural foods in Toronto. They will be examining how these foods are used to manifest a culture through cuisine. “Keystone ingredients, such as camel’s milk or sesame oil have great importance to the meal,” she says. “Not being able to choose what you eat is dis-empowering.” read more »

Farmers get ahead of ...

Araina Bond | April 19, 2016

Anticipating Mother Nature has always been an important part of farming. Now farmers in Northeastern Ontario can make more informed decisions using real-time data about environmental conditions, thanks to Nipissing University researchers. The Nipissing team has created an online system called GeoVisage, which uses seven weather stations throughout Northern Ontario to collect data on microclimates. That includes air and soil temperature, relative humidity, wind speed, leaf wetness and photosynthetically active radiation — that is, sunlight plants can use for photosynthesis. read more »
quinoa plants

Quinoa puts down roots ...

Jessica Shapiro | April 14, 2016

Ancient Incas considered quinoa their most sacred food. Packed with protein, vitamins and amino acids, it gave them stamina, strength and energy needed for survival. No wonder NASA has researched growing quinoa on long journeys to outer space. Despite the seed's explosion in world popularity over the past few years, including a massive increase in demand throughout North America, almost no farmers outside the Andes Mountains in South America grow it. Issues related to quality, supply, cost and importation have encouraged scientists to experiment with cultivating the crop in Ontario. At the Trent University Sustainable Agriculture Experimental Farm, Mehdi Sharifi is working with his students to make organic quinoa production viable for Ontario farmers. read more »
Larissa Barelli waters plants

Fine tuning fungi’s ...

Sharon Oosthoek | April 8, 2016

Nobody takes revenge like Mother Nature. After all, she created entomopathogenic fungi — organisms that not only kill crop pests, but offer up nutrients in the insects' bodies to the plant. "It's a cool mechanism," says University of Brock PhD biotech student Larissa Barelli who studies evolution of these fungi. "Certain species can drill through the insect's cuticle, grow within it and eat it from the inside. They can also release toxins that kill the insect. The fungi then transfers nitrogen from the insect to the plant." read more »
More Blogs »