[Quantum_Vaccuum (OP)]

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

[another_someone]

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.

[Quantum_Vaccuum (OP)]

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]

Just clarification, is TB a bacteria or a virus?

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

[paul.fr]

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

[another_someone]

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.

[DoctorBeaver]

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]

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.

[DoctorBeaver]

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.

[iko]

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

[Quantum_Vaccuum (OP)]

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]

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.

[Quantum_Vaccuum (OP)]

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

[another_someone]

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.

[Quantum_Vaccuum (OP)]

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

[another_someone]

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.

[iko]

Hi TBscaredfans,

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

from:   http://en.wikipedia.org/wiki/Tuberculosis

[another_someone]

Hi TBscaredfans,

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

from:   http://en.wikipedia.org/wiki/Tuberculosis

But:

http://en.wikipedia.org/wiki/Mycobacterium_bovis

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.

[iko]

Hi TBscaredfans,

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

from:   http://en.wikipedia.org/wiki/Tuberculosis

But:

http://en.wikipedia.org/wiki/Mycobacterium_bovis

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

[another_someone]

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.