Search This Blog

Thursday, 15 November 2012

Cancer and Inflammation Pathway Found

A few years ago there was a very simple view of the relationship between the immune system and cancer. Immune cells, such as natural killer cells, had the capacity to destroy cancer cells in the laboratory. So they must do so inside the body, surely? The development of cancer was blamed on a failure of the immune system's surveillance - a failure to spot microtumours and dispatch them before they could take root.
Complementary therapists seized on this idea, reasoning that if you could boost up the immune system with a beautiful thought, a massage or a potion then you could reduce your chances of getting cancer - or even help the immune system attack fully-developed tumours.
But now a far more complicated picture is emerging. It is not a simple case of cancer cells bad and immune cells good.  We now know, for instance, that immune cells can sometimes help the cancer cells instead of attacking them.
Some recently-published research has demonstrated a new connection between cancer and immune cells. It has long been suspected that prolonged inflammation, for example in the stomach lining, might cause cancer but exact molecular mechanisms are hard to pin down. A team in Ohio has now discovered a link between immune cells, inflammation and a form of blood cancer. They were able to demonstrate this using a combination of mice and human leukaemia cells.
Immune cells communicate with other cells by releasing a range of chemicals, collectively know as cytokines or interleukins.  One of these, known as Interleukin-15, is released during inflammation. Inflammation is useful as a short term measure but if it becomes long term, you have an excess of Interleukin-15 in circulation.
The team has demonstrated that an excess of Interleukin-15 can stimulate a type of immune cell known as a large granular lymphocyte (LGL) to become malignant giving rise to a rare form of leukaemia.
Not content with this breakthrough, they managed to "turn off the pathway" and reverse the process - curing the mice of their LGL leukaemia.
So here we have a double success - demonstration of a molecular pathway whereby an immune chemical associated with inflammation can cause a specific cancer - and reversing the process.  
So if a complementary therapist tells you that something will “boost your immune system” proceed with caution. The immune system is not a simple device. It’s a vast collection of cells and complex chemicals, interacting in ways that we are only beginning to understand in detail.

Friday, 9 November 2012

Should 'Flu Vaccination be a Condition of Employment for Health Workers?

A recent editorial in the Canadian Medical Association Journal makes the case for mandatory flu vaccinations for health care workers.
There are a number of arguments for requiring health care workers to take up this vaccine.
Health workers in many settings tend to be exposed to flu sufferers during an epidemic and if they fall ill, services are likely to be impaired. Absence rates amongst NHS staff are high when compared to most other UK employment sectors, which puts a significant pressure on hard pressed hospital budgets.
Even more persuasive is the argument that health professionals are in contact with vulnerable patients and could infect them. Individuals sometimes argue that they do not need the flu vaccine because they "never get ill" or that, if they do get 'flu, they will stay at home. The Canadian article points out that flu can be infectious before symptoms appear. We also know that not all those infected with a virus exhibit obvious symptoms.
Age, pregnancy, injury, surgery and acute illness can all suppress the immune system. So imagine your vulnerable relative, entering a health care setting, minus a flu infection this winter. Would you want them cared for by an unvaccinated doctor or nurse?
There is a very strong argument that those who work in health and care settings should be required to have this vaccination.
Employers in the UK have traditionally been wary of imposing health-related rules on their employees. Smoking bans at work, for instance, were slow to take hold. Some would argue that imposing the requirement for vaccination would be discriminatory or an infringement of human rights.
A requirement on health workers would not be discriminatory if applied to all. It does not fall under any section of anti-discrimination law. As far as human rights are concerned, exemptions could be allowed in certain circumstances - if, for instance, someone had a religious objection to vaccination or was advised against it for medical reasons.
Otherwise there would seem to be nothing wrong in saying: It is a requirement of employment that all our staff are up to date with their vaccinations, including annual flu vaccine.
Make it part of the contract of employment when people join, so that new employees are clear that it is a requirement. Use peer pressure to encourage existing staff to comply. To prioritise employee rights over the safety of patients, would seem to be perverse logic.