Mycobacterium avium paratuberculosis (MAP)

[Aldous]

While continuing my own research on tuberculosis over the years and in spite of some people encouraging me to neglect the problem because of their shoot the messenger attitude, I was surprised to find some articles and books published 70 to 100 years ago that claim that almost 100% of the population become infected with TB sometime in their lifetimes.
Some references can be found here:
http://sciliterature.50webs.com/TB2.htm

Also, a long time ago, I noticed that in TB reports, white people would usually be at the bottom of the list on race and ethnic groups (lower rates among whites). I found some articles that claim that tuberculosis began to increase in Europe starting in the 1400s, reached a peak in the 1700s and gradually declined after this. Tuberculosis was relatively rare outside of Europe prior to the 1800s. This resulted in European decendants developing a higher resistance to TB because of natural selection.

Its also known that genetics is a big factor in your resistance to TB. Before the bacteria was discovered that caused tuberculosis, some people thought it was inherited. Active tuberculosis tends to run in some families because of their lower resistance to TB. What's inherited is your ability to resist the disease from the TB.

I think this is useful information. If most of us had recent ancestors that were infected with TB (tubercle bacillus), and you don't have any family history of active tuberculosis then you probably inherited a high resistance to TB and there's a good chance you will never get any disease from it if you get infected with it as long as your immune system can keep it in check.

I also found some references that say that 10-15 million people in the US have latent tuberculosis right now. Some TB reports from the CDC say that up to 13 million people in the US have latent tuberculosis. This is about 4% of the population. I figured that if this group of people are spread throughout the US more or less evenly (more would be in more crowded areas), then most likely we all come into contact with people who have tuberculosis now and then, in spite of the wrong assumption that wherever you go there is no TB there. I use to assume this and I think most people assume this, too. Latent TB isn't contagious and even if you had brief contact with someone who had active TB in public, chances are you won't become infeccted with it. To become infected with TB, you need close contact with someone who has active TB for a long period of time, typically every day.

[Aldous]

Remove the s and the link works.
http://sciliterature.50webs.com/TB2.htm

[Aldous]

Why are there pathogenic Mycobacterium species, that cause tuberculosis, leprosy, etc.? I found some articles about experiments where they infected amoebae with various Mycobacterium species including M. tuberculosis and thought the pathogenic species must have evolved from bacteria like these. Its known that some Mycobacterium species can act as parasites and/or endosymbionts with amoebae. I found this article later. TB and leprosy involve infection of macrophages.
https://en.wikipedia.org/wiki/Macrophage

An interesting feature of many mycobacterial species is their ability to survive inside amoebae, leading to the classification of mycobacteria as ‘amoeba-resistant micro-organisms' (Greub & Raoult, 2004). The mechanisms used by macrophages and amoebae for phagocytosis, phagolysosome formation and digestion of intracellular bacteria are very similar (Allen & Dawidowicz, 1990a, b; Brown & Barker, 1999; Greub & Raoult, 2004; Winiecka-Krusnell & Linder, 2001). Reciprocally, the strategies employed by bacteria to escape destruction by macrophages or amoebae are also similar. This supports the theory that an evolutionary selection for survival in environmental protozoa has enabled intracellular pathogenic bacteria to develop the capacities necessary for survival in macrophages (Brown & Barker, 1999; Steinert et al., 1998; Winiecka-Krusnell & Linder, 2001). In this context, it is interesting that passage through amoebae can enhance the virulence of pathogenic intracellular bacteria and that there exists a correlation between the virulence of mycobacterial species and survival in amoebae (Cirillo et al., 1997).

https://www.microbiologyresearch.org...mic1512403.pdf

[Aldous]

Years ago, I found an old article that discussed the possibility of measles, the flu and diptheria to cause latent TB to turn active. Later, I found some other articles that mention other diseases, too, such as pertussis. Also, being infected with both HIV and TB increases the risk that the TB will turn active and the HIV infection turns into AIDS faster. The BCG vaccine for TB is used in a lot of countries, but not in the USA. Its not 100% effective, but measles, flu, diphtheria, etc. vaccines are highly effective. Preventing active TB seems to be another good reason to make sure you're vaccinated against measles, flu and diphtheria. In the summer of 2020 when I found out that the MMR vaccine provided protection against COVID, the next day I went to the pharmacy and got the first dose of the MMR vaccine and then got the second dose a month later. MMR = measles mumps rubella


This is interesting, activation of latent TB by COVID.

Activation of tuberculosis in recovered COVID-19 patients: a case report

In these two cases, the authors observed the development of active TB after a period of COVID recovery. Two patients who were admitted to the hospital complained mainly, among other symptoms, of fever and a continuous cough after a period of COVID-19 recovery.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9949802/

[Aldous]

A long time ago I found an old article that said that some people don't become infected with TB even after repeated exposure to it. I tried to find it again, but couldn't find it. I found two more recent articles that seemed to say that, but they were vague on that. I found this recently which appears to say this.

Intriguingly, complete resistance to infection is observed in some individuals (termed resisters) after intense, continuing M. tuberculosis exposure.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6170664/
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“Infection resisters” are broadly defined as individuals who despite significant exposure to Mycobacterium tuberculosis remain persistently unreactive to conventional detection assays, suggesting that they remain uninfected or rapidly clear their infection early on following exposure

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6774050/
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Infection free “resisters” among household contacts of adult pulmonary tuberculosis
https://journals.plos.org/plosone/ar...l.pone.0218034

[Aldous]

Mycobacterium marinum

I found this recently. I read about Mycobacterium marinum before. It can infect your skin and doesn't spread to the rest of your body because it can't grow at your body temperature. It often infects cold blooded animals, ie. fish and reptiles. It can make you test positive to the TB skin test. Also, if you get the BCG vaccine you will test positive, too. The BCG vaccine isn't used in the USA. M. marinum is used in TB research.

How to identify and avoid catching fish TB, Tuberculosis Mycobacterium marinum
https://www.youtube.com/watch?v=RW_U4tvtO5k

I found this years ago:

A reactive tuberculin skin test in Anne Arundel County is more likely to represent M. marinum infection than tuberculous infection.

https://pubmed.ncbi.nlm.nih.gov/8544670/

M. marinum is in the phylogenetic tree shown in figure 1 (middle figure) here:
https://journals.plos.org/plosntds/a...l.pntd.0002544
https://od.lk/s/OV8xOTU4ODcyMDdf/MycoTree.png

[Aldous]

I read in one book that TB survives outside the body for about a half a year. Another book I read says TB survives under optimum conditions for a year or more. Looks like they didn't have much success here:

Attempts to revive Mycobacterium tuberculosis from 300-year-old human mummies
https://academic.oup.com/femsle/article/283/1/54/547701

[Aldous]

According to this book, dead TB can cause tuberculosis. There's also a lot of information in the book about the effect of sunlight on bacteria. I read in at least one place that about a hundred years ago, you could go into major cities, collect dust in public places and find TB in the dust. TB could also be found in the dirt and dust in the streets and street sweepers had high rates of TB.

Fate of Tubercle Bacilli Outside the Animal Body
by C. R. Briscoe
https://tinyurl.com/c9bk2jhk
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Here you can see a lot of paper patents you had to search before they put everything on computer databases. There were some patents going back to the 1800's and there was a lot of dust on the patents. I had an idea that there might be TB in the hundred year old dust. It would be dead by now, but if TB was in it then it might cause tuberculosis in anyone who searched these patents regularly. Two patent searchers told me they had TB skin tests and tested negative. One of them got the skin test after he had a chest x-ray after being hit by a car and the other one got a TB skin test once a year because he did counselling in a hospital.

https://www.flickr.com/photos/62345920@N00