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Author Topic: Is TB (tuberculosis) returning to the UK and other western countries?  (Read 35211 times)

Offline Quantum_Vaccuum

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I have heard some rumors of Tuberculosis becoming immune to the vaccinations that are given to us today, is this true?
« Last Edit: 06/04/2008 16:08:41 by chris »


 

another_someone

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I have heard some rumors of Tuberculosis becoming immune to the vaccinations that are given to us today, is this true?

This is partly true.

As I understand it, tuberculosis vaccines were never 100% effective, but they have not become any less effective over time.

Some strains of TB have become resistant to antibiotics,  so those people who do become infected are now more difficult to treat.

There is the additional problem of a significant sub population who now have compromised immune systems (people who are suffering from AIDS, or people on immunosuppresents because they are recipients of transplanted organs).  For these people, even if they had received vaccines, the vaccines would be compromised because they rely on a properly functioning immune system.  This is the group of people who are presently at highest risk from TB.
 

Offline Quantum_Vaccuum

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As I understand it, tuberculosis vaccines were never 100% effective, but they have not become any less effective over time.

Some strains of TB have become resistant to antibiotics,  so those people who do become infected are now more difficult to treat.

Just clarification, is TB a bacteria or a virus?
 

another_someone

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Just clarification, is TB a bacteria or a virus?

Bacteria (which is why we have used antibiotics to treat it).
 

paul.fr

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Aren't the increased cases in the UK being blamed on migration? Or is this just media scare stories?
 

another_someone

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Aren't the increased cases in the UK being blamed on migration? Or is this just media scare stories?

I think there is en element of this.

Firstly, outside of the major risk groups (homosexuals, intravenous drug users, haemophiliacs), then next largest risk group for HIV itself are recent immigrants.

Secondly, immigrants from some areas of the world have not habitually been vaccinated against TB (or many other diseases for which vaccines are commonly administered during childhood in this country).

Thirdly, immigrants often live in more crowded conditions than the average native population (not necessarily more so than the most deprived of the native population, but typically more so than the average), and this provides a good breeding ground for many diseases, not least for TB.
 

Offline DoctorBeaver

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Another source is people returning from 3rd world countries who had not been priorly inocculated. This group has been increasing substantially with the advent of cheaper air travel & exotic holidays.
 

another_someone

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Another source is people returning from 3rd world countries who had not been priorly inocculated. This group has been increasing substantially with the advent of cheaper air travel & exotic holidays.

Although this is the case for many diseases, I thought it was less the case for TB.

Firstly, the level of takeup of inoculation for TB I believe is fairly high in this country.

Secondly, as I understand it (and maybe I will be corrected in my understanding), TB is not that easy to acquire (probably easier to acquire from drinking infected milk) - and for human to human contact would generally require a significant amount of time in close proximity with the infected person.
 

Offline DoctorBeaver

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Another source is people returning from 3rd world countries who had not been priorly inocculated. This group has been increasing substantially with the advent of cheaper air travel & exotic holidays.

Although this is the case for many diseases, I thought it was less the case for TB.

Firstly, the level of takeup of inoculation for TB I believe is fairly high in this country.

Secondly, as I understand it (and maybe I will be corrected in my understanding), TB is not that easy to acquire (probably easier to acquire from drinking infected milk) - and for human to human contact would generally require a significant amount of time in close proximity with the infected person.

That's not my understanding of the situation. I'll try to look into it further.
 

Offline iko

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Tuberculosis bacterial strains are becoming more and more resistant to standard chemotherapy.
Hygienic standards and social condition (poverty, malnutrition etc.) seem to make the real difference and allow the slow rise of these dreadful pathogens.
In the old days a drop of TB cases was observed either in vaccinated or unvaccinated populations, at the same rate, when health conditions had been simultaneously improved.

ikod
« Last Edit: 25/09/2007 22:17:39 by iko »
 

Offline Quantum_Vaccuum

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Although this is the case for many diseases, I thought it was less the case for TB.

Firstly, the level of takeup of inoculation for TB I believe is fairly high in this country.

Secondly, as I understand it (and maybe I will be corrected in my understanding), TB is not that easy to acquire (probably easier to acquire from drinking infected milk) - and for human to human contact would generally require a significant amount of time in close proximity with the infected person.


How could there be infected milk? Like the tuberculosis milk?
 

another_someone

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How could there be infected milk? Like the tuberculosis milk?

Cows can be infected by TB, and this can be passed on through their milk.  This used to be a problem in the 19th century, but now cattle with TB must be slaughtered (this caused a political turmoil recently as the government forced a Hindu sect to kill their sacred bull because it had TB), but most importantly, it was the mandatory pasteurisation of milk that stopped TB being passed on in milk.
 

Offline Quantum_Vaccuum

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is there any other "main" way that tuberculosis is passed around?
 

another_someone

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is there any other "main" way that tuberculosis is passed around?

The primary means that I am aware of these days is through breathing in aerosol droplets from an infected person, but this is not a very efficient way of transmitting the disease, which is why you need to be in close confinement with an infected person for a prolonged period of time (e.g. living in crowded conditions with an infected person).  Ofcourse, there are always the laws of probability, and you may easily catch the disease, or it might be very much more difficult.

The other problem is that even when you have caught the disease, you may be symptomless for many years, or may even live out your life with ever showing any symptoms of the disease, or may show symptoms in adulthood after having caught the disease as a child (again, the more stressful your environment, the more likely you are to display symptoms).  The long incubation time makes it impractical to manage the disease simply through quarantine measures.
 

Offline Quantum_Vaccuum

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o wow, that is really harsh conditions, how did the disease first strike? Like was it a mutant cow or something?
 

another_someone

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o wow, that is really harsh conditions, how did the disease first strike? Like was it a mutant cow or something?

There is still much debate as to whether the cows themselves can get it from badgers (the disease is rife amongst badgers).

It is a disease that has been with humans as far back as records go, and as far as I am aware nobody has yet done the research that might answer the question as to where in may have come from in the antiquity of time.
 

Offline iko

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Hi TBscaredfans,

I must add that bacteria infecting cows are different from those affecting human beings:  Mycobacterium bovis versus Mycobacterium tuberculosis. 


 

another_someone

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Hi TBscaredfans,

I must add that bacteria infecting cows are different from those affecting human beings:  Mycobacterium bovis versus Mycobacterium tuberculosis. 



But:

http://en.wikipedia.org/wiki/Mycobacterium_bovis
Quote
M. bovis is usually transmitted to humans via infected milk, although it can also spread via aerosol droplets. Actual infections in humans are rare, mostly due to pasteurisation killing any bacteria in infected milk; as well, cattle are randomly tested for the disease and immediately destroyed if infected. However, in areas of the developing world where pasteurisation is not routine, M. bovis is a relatively common cause of human tuberculosis.

So the distinction that M. Bovis is not infectious to humans does not exist - both forms do infect humans, but M.Bovis is now managed through pasteurised milk.
 

Offline iko

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Hi TBscaredfans,

I must add that bacteria infecting cows are different from those affecting human beings:  Mycobacterium bovis versus Mycobacterium tuberculosis. 



But:

http://en.wikipedia.org/wiki/Mycobacterium_bovis
Quote
M. bovis is usually transmitted to humans via infected milk, although it can also spread via aerosol droplets. Actual infections in humans are rare, mostly due to pasteurisation killing any bacteria in infected milk; as well, cattle are randomly tested for the disease and immediately destroyed if infected. However, in areas of the developing world where pasteurisation is not routine, M. bovis is a relatively common cause of human tuberculosis.

So the distinction that M. Bovis is not infectious to humans does not exist - both forms do infect humans, but M.Bovis is now managed through pasteurised milk.

Yes George,

my point tended to concentrate on human TB.
As you wrote, the infection from milk and bovines has almost disappeared.
Epidemiology of TB is now restricted to inter-human infections.
I think that our discussant, QV, meant TB infection in developed countries.
Mixing these two 'epidemics' is a bit confusing, in my opinion.

ikod
« Last Edit: 27/09/2007 17:13:25 by iko »
 

another_someone

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Yes George,

my point tended to concentrate on human TB.
As you wrote, the infection from milk and bovines has almost disappeared.
Epidemiology of TB is now restricted to inter-human infections.
I think that our discussant, QV, meant TB infection in developed countries.
Mixing these two 'epidemics' is a bit confusing, in my opinion.

ikod

I did say myself that bovine TB was a major cause in the 19th century, and not contemporary.

On the other hand, as Paul also mentioned, we do see TB in immigrants, and that could easily be from a country where bovine TB remains a risk.
 

Offline iko

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You're right as usual, George.

Now let me remind that: "Even dealing with TB, never forget vitamin D"
http://www.sciencedaily.com/releases/2007/05/070514140525.htm
from the Imperial College of London, 5/2007

Never mind, it is my duty around here!  ;D

ikod



Quackery...revisited in 2006!

This comes out crossing "cod liver oil" and Quackery on Google Images!



...Near the beginning of TB treatment in sanatoria, it became known that the sun helped to kill TB bacteria (see heliotherapy). When the Sun's UV rays hit human skin, vitamin D is produced. Naturally, when cod fish were found to be rich in vitamin D, it followed that their oil was sold as "liquid sunshine" (this was a real advertisement in the Valley Echo, March 1944). Cod Liver Oil is still used in "traditional" medicine today, and as an important dietary supplement, but no real evidence exists that it helps to cure tuberculosis.

http://www.lung.ca/tb/tbhistory/treatment/



...NO real evidence? Let's cross quickly "Tuberculosis and vitamin d" on PubMed database...




Toll-like receptor triggering of a vitamin D-mediated human antimicrobial response.


Liu PT, Stenger S, Li H et al.
In innate immune responses, activation of Toll-like receptors (TLRs) triggers direct antimicrobial activity against intracellular bacteria, which in murine, but not human, monocytes and macrophages is mediated principally by nitric oxide. We report here that TLR activation of human macrophages up-regulated expression of the vitamin D receptor and the vitamin D-1-hydroxylase genes, leading to induction of the antimicrobial peptide cathelicidin and killing of intracellular Mycobacterium tuberculosis. We also observed that sera from African-American individuals, known to have increased susceptibility to tuberculosis, had low 25-hydroxyvitamin D and were inefficient in supporting cathelicidin messenger RNA induction. These data support a link between TLRs and vitamin D-mediated innate immunity and suggest that differences in ability of human populations to produce vitamin D may contribute to susceptibility to microbial infection.
Science. 2006 Mar 24;311(5768):1770-3. Epub 2006 Feb 23.





The effect of vitamin D as supplementary treatment
 in patients with moderately advanced pulmonary tuberculous lesion.

Nursyam EW, Amin Z, Rumended CM.
Dept.Int.Med.University of Indonesia-dr.Cipto Mangunkusumo Hospital, Jakarta.

AIM: to compare the vitamin D group of pulmonary tuberculosis patients with a placebo group in terms of clinical improvement, nutritional status, sputum conversion, and radiological improvement. METHODS: sixty seven tuberculosis patient visiting the Pulmonary Clinic, of Cipto Mangunkusumo Hospital, Jakarta, from January 1st to August 31st, 2001 were included in this study. The subjects were randomised to receive vitamin D (0.25 mg/day) or placebo in a double blind method, during the 6th initial week of Tb treatment. The rate of sputum conversion, complete blood counts, blood chemistry as well as radiologic examination were evaluated. RESULTS: there were more male patients than females (39:28), 78.7% were in the productive age group, 71.6% had low nutritional status, 62.4% with low education level, and 67.2% with low income. One hundred percent of the vitamin D group and only 76.7% of the placebo group had sputum conversion. This difference is statistically significant (p=0.002). CONCLUSION: the sputum conversion had no correlation with the hemoglobin level, blood clotting time, calcium level, lymphocyte count, age, sex, and nutritional status. There were more subjects with radiological improvement in the vitamin D group.

Acta Med Indones. 2006 Jan-Mar;38(1):3-5.




Prevalence and associations of vitamin D deficiency in foreign-born persons with tuberculosis in London.

Ustianowski A, Shaffer R, Collin S, Wilkinson RJ, Davidson RN.
Dept.Infect.Trop.Med.- Northwick Park Hospital, Harrow, Middlesex HA1 3UJ, UK. ustianowski@doctors.org.uk

OBJECTIVES: The incidence of tuberculosis (TB) is high amongst foreign-born persons resident in developed countries. Vitamin D is important in the host defence against TB in vitro and deficiency may be an acquired risk factor for this disease. We aimed to determine the incidence and associations of vitamin D deficiency in TB patients diagnosed at an infectious diseases unit in London, UK. METHODS: Case-note analysis of 210 unselected patients diagnosed with TB who had plasma vitamin D (25(OH)D3) levels routinely measured. Prevalence of 25(OH)D3 deficiency and its relationship to ethnic origin, religion, site of TB, sex, age, duration in the UK, month of 25(OH)D3 estimation and TB diagnosis were determined. RESULTS: Of 210 patients 76% were 25(OH)D3 deficient and 56% had undetectable levels. 70/82 Indian, 24/28 East African Asian, 29/34 Somali, 14/19 Pakistani and Afghani, 16/22 Sri Lankan and 2/6 other African patients were deficient (with 58, 17, 23, 9, 6 and 1 having undetectable levels, respectively). Only 0/6 white Europeans and 1/8 Chinese/South East Asians had low plasma 25(OH)D3 levels. Muslims, Hindus and Sikhs all had equivalent rates of deficiency though Hindus were more likely to have undetectable levels (odds ratio 1.87, 95% CI 1.27-2.76). There was no significant association between 25(OH)D3 level and site of TB or duration of residence in the UK. There was no apparent seasonal variation in either TB diagnosis or 25(OH)D3 level. CONCLUSIONS: 25(OH)D3 deficiency commonly associates with TB among all ethnic groups apart from white Europeans, and Chinese/South East Asians. Our data support a lack of sunlight exposure and potentially a vegetarian diet as contributors to this deficiency.

J Infect. 2005 Jun;50(5):432-7.





Those nurses and doctors should be proud and rest in peace.
They gave cod liver oil to their TB patients for years
without any controlled study or scientific evidence,
wisely adopting the old "ex-adjuvantibus" criteria.
They did just the right thing to do in those days
when treatments available were unsatisfactory
and only some patients recovered completely.
Evidence is slowly coming out
more than fifty years later.


ikod



Before the availability of drugs that successfully cured the body of tubercular infections, a widely accepted treatment for non-pulmonary tuberculosis was sunbathing. The sun had sometimes been blamed for increased activity in tubercular infection of the lungs and was therefore not used to treat this form of tuberculosis. However, the Sun offered several curative properties to those suffering from other types of tuberculosis. Sun treatment was used in the treatment of tuberculosis of the glands, bones, joints, peritoneum, skin, eyes, genito-urinary tract, and others.

There were several reasons for the prescription of sun treatment to tuberculosis patients. First of all, the sun acts as a bactericide, killing the Tubercular bacillus organisms that cause the disease. Exposure to moderately hot temperatures for extended periods of time is sufficient to kill off these bacteria and clear up infections. Furthermore, ergosterol, present in the skin in converted by the sunís UV rays into vitamin D, which was thought to do further damage to the TB bacilli.
 
Sunlamps like the ones pictured here were often used to replace natural sunlight in sun-therapy, or "heliotherapy" for tuberculosis (ca. 1925).


      

http://home.tiscalinet.ch/biografien/images/koch.jpg
http://www.lung.ca/tb/images/061_sun_lamps.jpg
http://www.mmaonline.net/Publications/MNMed2005/November/Images/sun.gif






"Il sole dona la vita, il sole se la riprende" M.U. Dianzani 1975.
« Last Edit: 04/11/2007 10:35:50 by iko »
 

Offline Quantum_Vaccuum

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wait, let me get this right, so TB originated from badgers?
 

another_someone

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wait, let me get this right, so TB originated from badgers?

I don't think we actually know (I would not even be sure that cows, humans, and badgers, forms the entire list of species affected by TB).

Badgers are a risk to cows because they can move from field to field, so they can get infected by a cow in one field, and then pass the infection on to a cow in another field.  We don't know which got it first (or if they both got it from somewhere else).
 

Offline Quantum_Vaccuum

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so wouldn't other small mammals also be a big cause to TB?
 

another_someone

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so wouldn't other small mammals also be a big cause to TB?

There is no reason it should be limited to small mammals (although I suppose in the highly managed environments of Europe, small mammals tend to get around more); but as I said above, I don't actually know which other species are susceptible (although I did see reference to some variants of TB affecting voles).

One interesting issue is that the bacteria that causes TB is closely related to the bacteria that causes leprosy.

Reading background to this, I noticed:

http://en.wikipedia.org/wiki/Nontuberculous_mycobacteria
Quote
Over the past 25 years, there has been a dramatic increase in the number of NTM cases seen by clinicians across the United States and Canada.

The correct name of NTM is "nontuberculous mycobacteria." There is no such bacteria called "nontuberculosis microbacteria."

Mycobacteria are a family of small, rod-shaped bacilli that can be classified into 3 main groups for the purpose of diagnosis and treatment:

  • Mycobacterium tuberculosis complex which can cause tuberculosis: M. tuberculosis, M. bovis, M. africanum, , M. microti and M. canetti.
  • M. leprae which causes Hansen's disease or leprosy.
  • Nontuberculous mycobacteria (NTM) are all the other mycobacteria which can cause pulmonary disease resembling tuberculosis, lymphadenitis, skin disease, or disseminated disease. Pulmonary NTM infections include: MAC (mycobacterium avian complex), which includes M. avium and M. intracellulare; faster-growing M. abscessus, M. chelonae, and M. fortuitum; and less common strains such as M. kansasii and M. xenopi.

Unlike TB and leprosy, which are primarily spread by human-to-human contact, NTM is believed to be contracted from the environment, hence its alternative label, "environmental bacteria." NTM is believed to exist naturally in soil and water.
« Last Edit: 29/09/2007 14:49:52 by another_someone »
 

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