Believers of old folk wisdom now have scientific evidence to support the idea that cold weather or drafts makes people more susceptible to the common cold.
Yale News is reporting that a team of Yale researchers have published a report that lower temperature in the nasal cavity diminishes the body's immune response, reducing the ability to ward off rhinovirus.
They found that the innate immune response to the rhinovirus is impaired at the lower body temperature compared to the core body temperature. The reason for the impairment is the lower production of Type I Interferon in the cooler nasal cavities. Type I Interferon is a signaling agent to signal the body's antiviral immune responses. With reduced immune response the rhinovirus is more able to establish a foot hold.
"The study also strongly suggested that the varying temperatures influenced the immune response, rather than the virus itself" said study senior author and Yale professor of immunobiology Akiko Iwasaki.
The study abstract (paywalled) at the Proceedings of the National Academy of Sciences explains that rhinovirus, the most frequent cause of the common cold, replicate better at the cooler temperatures (33°C) found in the nasal cavity than at lung temperature (37°C), but previously the underlying mechanisms for this difference were not known. The principal discovery is the reduced interferon signaling at cooler nasal temperatures.
One would think that the Asian tradition of wearing surgical masks when they have a cold might be more effective if worn before they catch a cold.
(Score: 3, Informative) by Joe on Saturday January 10 2015, @08:43PM
I don't think that it is very likely that rhinoviruses benefit humans. Human rhinoviruses are too diverse to provide protection against other rhinoviruses (which is why you don't just get the cold once and have lifelong immunity) and it is unlikely that responses against rhinovirus antigens would provide cross-protection to other pathogens.
Viruses can carry information from other viruses through sloppy replication (recombination or packaging segments) or even whole viruses (Sputnik virophage can be packaged inside of Mamavirus).
Lack of knowledge in a field can sometimes be an asset. Outsiders can question basic assumptions that are "known" to be true or bring new insight to stale ideas.
- Joe
Sputnik virophage
https://en.wikipedia.org/wiki/Sputnik_virophage [wikipedia.org]
https://www.ncbi.nlm.nih.gov/pubmed/18690211 [nih.gov]
(Score: 2) by buswolley on Saturday January 10 2015, @09:09PM
Thanks for the response.
Are rhinoviruses particularly 'diverse' because they are particularly good at "carrying information from other viruses through sloppy replication"? If so, then my hpothesis migh have some life in it ;)
subicular junctures
(Score: 2) by Joe on Saturday January 10 2015, @09:44PM
If you stick with the technical definition of symbiotic (which includes parasitism), then I would say that your hypothesis is 100% correct due to the diversity and specificity of human rhinoviruses.
Rhinoviruses are positive RNA viruses, so they have a high mutation rate and can undergo recombination readily. This means that they change rapidly, which makes it difficult for the immune system to recognize the virus. Furthermore, the conserved parts of the virus that don't change as much are inaccessible to antibodies. All this adds up to a large family (~100 serotypes) that do the same things (conserved function) but look very different on the superficial level (which is what antibodies recognize).
- Joe