Not all viruses mutate so readily. The virus sticks to the upper respiratory tract, where the body does not treat it like a threat. A study published in the New England Journal of Medicine found that it would take more than years for even half of your antibodies to disappear after a measles or a mumps infection. The same study found similar results for Epstein-Barr virus, which causes mono. That same study found that it takes around 50 years to lose half of our chickenpox antibodies, and 11 years to lose half of our tetanus antibodies.
That means that without a booster shot, you could theoretically become infected with one of these diseases as an adult. And in those cases, the immune system would be at full capacity again and again because of the reinfections. Bacteria and viruses tend to be symmetrical with a repetitive pattern of proteins across their surfaces. One theory suggests that we mount a larger and longer-lasting immune response to more repetitive-looking pathogens.
For example, the antibodies we produce against variola, the highly repetitively-structured smallpox virus , last a lifetime. So, will immunity to the new coronavirus — whether that comes from infection or a vaccine — be as long-lived as our immunity to smallpox, or will we need a new vaccine every year? All the evidence both from natural infections and from vaccine trials suggest that most people are making neutralizing antibodies, the variety which prevents viruses from entering our cells, Jenkins said.
Isobel Whitcomb is a contributing writer for Live Science and covers the environment, animals and health. She studied biology at Scripps College in Claremont, California while working in two different labs, and completing a fellowship at Crater Lake National Park.
She lives in Brooklyn, where you can find her riding her bike or running in Prospect Park. Find Isobel on Twitter IsobelWhitcomb.
A version of this article was originally published at Live Science and has been republished here with permission. Live Science can be found on Twitter LiveScience. Influenza, for example, has eight distinct segments to its genome, increasing its ability to form new combinations that can include elements of avian flu, swine flu and human flu.
It's these recombined versions of the flu that have the potential to cross over and actually spread through a new host. And as the flu spreads, its list of available hosts spreads as well. Until five years ago, for example, dogs were not susceptible to influenza, said Dr. But the flu has since spread to canines through horses.
The kind of virus likely to thrive is also a function of its environment, he said. A virus that quickly kills its host as it spreads is more likely to thrive in densely populated areas where it can out-compete other viruses, but would die out when the supply of new hosts is in short supply, he said.
Conversely, a virus that incubates in the host for weeks and spreads slowly is more likely to thrive in animals like migratory birds, he said. Human populations have grown over the past few centuries, and in recent decades, the demand for pork and chicken has soared. That has led to the proliferation of large, dense farms with thousands of animals.
Waltner-Toews said those result in a number of factors that boost transmission of viruses such as influenza:. Science FAQ: How viruses mutate More than people have died in Mexico as a result of an outbreak of swine flu, a strain of the influenza virus that normally targets pigs but has occasionally mutated enough to infect and spread in humans.
Just as our immune systems kill off one version of the virus, another emerges that our immune systems don't recognize. Not all viruses mutate so readily. For example, the polio virus can't easily change its genome, Jenkins said.
That's why we've been so successful at almost eradicating it. The virus sticks to the upper respiratory tract, where the body does not treat it like a threat. In a preprint study meaning it hasn't been peer reviewed yet published in the database MedRxiv , 10 out of patients who had mild symptoms recovered from COVID without developing detectable antibodies. A study published in the New England Journal of Medicine found that it would take more than years for even half of your antibodies to disappear after a measles or a mumps infection.
The same study found similar results for Epstein-Barr virus, which causes mono. Still, antibody responses don't always last a lifetime.
That same study found that it takes around 50 years to lose half of our chickenpox antibodies, and 11 years to lose half of our tetanus antibodies. That means that without a booster shot, you could theoretically become infected with one of these diseases as an adult. Scientists still aren't sure why we maintain our antibody responses longer for some diseases compared with others. It's possible that some of these more common diseases, such as chickenpox and mono, actually are reinfecting us more frequently than we realize, but that the antibodies we do have crush the infection before we notice, Jenkins said.
And in those cases, the immune system would be at full capacity again and again because of the reinfections. In contrast, "with tetanus, we're probably very rarely getting exposed, we're not stepping on a [dirty] nail very often. Related: Do rusty nails really give you tetanus? Those events might be quite rare, but because the virus replicates in an exponential way, even a rare event has a certain probability of occurring.
Do vaccines for viruses need to be updated when variants arise? Is that true with all viruses? Some people are trying to develop a universal influenza vaccine, to try to target the antibody generation toward a part of the molecule that cannot change without making the molecule not work anymore. But I think the evidence is that the variants are not escaping the vaccine dramatically. And of course, that also depends how quickly we can get this vaccination round to complete—how many different variants are going to emerge by the time most people are vaccinated.
The coronavirus definitely is not going to be like that. But if it does become endemic and it circulates in the population all the time, then there is a chance that a slightly different virus might emerge and we may need a booster. Another question is, as people become immune thanks to vaccinations, is that going to be a strong pressure on the virus? Variants may emerge because people are immune to the old virus. Taylor McNeil can be reached at taylor. Skip to main content.
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