TB Infection Control

Hi Hal,

Thanks for this. Of course, open air treatment is reminiscent of TB treatment, and that is discussed in the AJPH article. There is little evidence that the fresh air per se, its humidity, temperature, etc., had any effect, but sunlight certainly does, from a Vitamin D perspective. There is a growing literature base on the powerful effects of Vit D on the immune system. So, the benefits of sanatoria were several - separation of infectious patients from the general population and maximum Vit D stimulation, regardless of temperature. They exposed children almost naked to lots of sunlight in winter. It is unclear whether the strict bed rest routine was helpful in closing cavities, another goal of sun therapy for TB.

For pandemic flu, Vit D stimulation would also be helpful. In fact, a couple of virologists attempted to attribute the sparing effect of the VA UV study to the UV stimulation of Vit D on those wards - ignoring the low penetration of UV-C compared to sunlight. Separation should also be good for flu, but I doubt that there was any other true therapeutic benefit other than Vit D, which should not be underestimated.

Thanks,
Ed

Hi Ed,

Thanks for your comments.

What are your thoughts on temperatures? Temperature seems to me to be potentially an important factor. Since many of the field hospitals described in the AJPH article were erected in the fall and winter, presumably temperatures were quite low, far lower than in modern housing and healthcare facilities. In my own lifetime I have seen a significant rise in the target temperatures for residential settings, perhaps as much as 8 degrees C. As I said, I have not looked for scholarly work on the effect of temperature, but I thought you or other members might have a view that summarizes what is known today.

Thanks,
Hal

I don't know much about temperature and infectious diseases. I think that there are two issues: the effect on the host and the effect on the organism. In C.S. Cox’s book, The Aerobiological Pathways of Microorganisms (1987), there were specific experiments at Porton Down (the Centre for Applied Microbiology & Research) on temperature effects (independent of humidity) on the viability of a variety of airborne test organisms in their Goldberg drum. I don't remember any details and am in Cancun for the IUATLD meeting without the book at hand. Paul also has the book and may remember.

The effects on the host revolve around the effects of temperature on infection or disease - ie, was your grandmother right about not getting a chill, wearing a hat, etc.? Does cold exposure predispose to the common cold? I believe there is some evidence that viruses residing in exposed parts - nose, etc, may activate/progress with exposure, but I don't know that literature. There may be literature on ambient temperature and immune responses, but if so, I am unaware of it.

I am sure there is nothing in the TB literature associating temperature with disease. However, I am aware of ...

I don't know much about temperature and infectious diseases. I think that there are two issues: the effect on the host and the effect on the organism. In C.S. Cox’s book, The Aerobiological Pathways of Microorganisms (1987), there were specific experiments at Porton Down (the Centre for Applied Microbiology & Research) on temperature effects (independent of humidity) on the viability of a variety of airborne test organisms in their Goldberg drum. I don't remember any details and am in Cancun for the IUATLD meeting without the book at hand. Paul also has the book and may remember.

The effects on the host revolve around the effects of temperature on infection or disease - ie, was your grandmother right about not getting a chill, wearing a hat, etc.? Does cold exposure predispose to the common cold? I believe there is some evidence that viruses residing in exposed parts - nose, etc, may activate/progress with exposure, but I don't know that literature. There may be literature on ambient temperature and immune responses, but if so, I am unaware of it.

I am sure there is nothing in the TB literature associating temperature with disease. However, I am aware of at least one paper on altitude and TB, trying to adjust for socioeconomic status:

"Altitude: a determinant for tuberculosis in Kenya?"
Mansoer JR, Kibuga DK, Borgdorff MW
Int J Tuberc Lung Dis. 1999 Feb;3(2):156-61
http://www.ncbi.nlm.nih.gov/pubmed/10091883

Hi,
Interesting thoughts. On this topic there is the article "Exposure to cold and respiratory tract infections", from INT J TUBERC LUNG DIS 2007; 11(9):938–943.
It seems our grandma was right (at least on this ...)
Please find abstract below.

There was a recent (early 2009)similar Lancet article if my memory is not playing me tricks, but I don't have access to this journal.

BTW: how to upload docs for the community ? Do I need to contact Sophie Beauvais (searched procedure on the website but no guidance found), and if yes how ?

QUOTE:
There is a constant increase in hospitalizations and mortality during winter months; cardiovascular diseases as well as respiratory infections are responsible for a large proportion of this added morbidity and mortality. Exposure to cold has often been associated with increased incidence
and severity of respiratory tract infections. The
data available suggest that exposure to cold, either
through exposure to low environmental temperatures or during induced hypothermia, increases the risk of developing upper and lower respiratory tract infections and dying from them; in addition, the longer the duration of exposure the higher the risk of infection. Although not all studies agree, most of the ...

Hi,
Interesting thoughts. On this topic there is the article "Exposure to cold and respiratory tract infections", from INT J TUBERC LUNG DIS 2007; 11(9):938–943.
It seems our grandma was right (at least on this ...)
Please find abstract below.

There was a recent (early 2009)similar Lancet article if my memory is not playing me tricks, but I don't have access to this journal.

BTW: how to upload docs for the community ? Do I need to contact Sophie Beauvais (searched procedure on the website but no guidance found), and if yes how ?

QUOTE:
There is a constant increase in hospitalizations and mortality during winter months; cardiovascular diseases as well as respiratory infections are responsible for a large proportion of this added morbidity and mortality. Exposure to cold has often been associated with increased incidence
and severity of respiratory tract infections. The
data available suggest that exposure to cold, either
through exposure to low environmental temperatures or during induced hypothermia, increases the risk of developing upper and lower respiratory tract infections and dying from them; in addition, the longer the duration of exposure the higher the risk of infection. Although not all studies agree, most of the available evidence from laboratory
and clinical studies suggests that inhaled cold air,
cooling of the body surface and cold stress induced by lowering the core body temperature cause pathophysiological responses such as vasoconstriction in the respiratory tract mucosa and suppression of immune responses, which are responsible for increased susceptibility to infections.
The general public and public health authorities
should therefore keep this in mind and take appropriate measures to prevent increases in morbidity and mortality during winter due to respiratory infections.