Doc Alan
2nd May 2013, 22:27
There are already health checklists for travel to and from the Philippines, and threads on various vaccines.
I don’t expect this thread to have a large number of views or responses, but hopefully it explains a little to those who are interested :smile:.
Our immune system is a defence mechanism which should protect the body not only against pathogens ( harmful bugs ) but also cancer cells. It can fail ( genetic, age, or illness ), over-react ( asthma ), or react inappropriately against normal cells ( auto-immune diseases like rheumatoid, thyroid / liver or type 1 diabetes ).
All normal people have INNATE immunity which is an immediate but not a specific response. We also develop ADAPTIVE immunity - antibodies are produced by plasma cells ( derived from B lymphocytes ), and T lymphocytes mount a “ cell-mediated “ response.
ACTIVE immunity is acquired by natural disease ( insufficient to kill the patient ) or vaccination. Vaccine types may be :-
A. Live attenuated ( weakened ) forms of viruses include the MMR ( measles, mumps and rubella ); or bacteria such as BCG for TB.
B. Inactivated – such as the ‘flu jab.
C. Detoxified toxins produced by a bug, such as for tetanus.
D. Extracts – such as pneumococcal vaccine, or from recombinant DNA ( hepatitis B ).
Of course there are “ contra-indications “ to vaccines, such as known hypersensitivity, weakened immune system, and pregnancy ; and side effects have to be considered before INFORMED consent is given.
PASSIVE immunity – gives immediate protection using plasma from immune individuals – preferably human immunoglobulins.
A. “ Normal “ ( pooled ) immunoglobulin is prepared from pools of at least 1000 donations of human plasma, for use in limited circumstances.
B. Disease-specific immunoglobulins are also prepared from pooled plasma of selected human donors with high levels of the antibody required – such as following exposure of an unimmunised individual to rabies. Rhesus-negative mothers may be given anti-D immunoglobulin.
Our knowledge of immunology is constantly improving. The immune system is complicated – a double-edged sword in that it efficiently rids the body of pathogens, cancer cells, and “ foreign “ agents … until it develops fault(s) or weakens with age.
Vaccination policies also change – to keep pace with mutating viruses like ‘flu and changing disease risks ; new knowledge and vaccine types ; and vary between countries reflecting disease patterns. Important diseases like dengue, malaria and HIV/AIDS STILL don’t have widely available vaccines, while tuberculosis needs a more effective one than BCG.
I don’t expect this thread to have a large number of views or responses, but hopefully it explains a little to those who are interested :smile:.
Our immune system is a defence mechanism which should protect the body not only against pathogens ( harmful bugs ) but also cancer cells. It can fail ( genetic, age, or illness ), over-react ( asthma ), or react inappropriately against normal cells ( auto-immune diseases like rheumatoid, thyroid / liver or type 1 diabetes ).
All normal people have INNATE immunity which is an immediate but not a specific response. We also develop ADAPTIVE immunity - antibodies are produced by plasma cells ( derived from B lymphocytes ), and T lymphocytes mount a “ cell-mediated “ response.
ACTIVE immunity is acquired by natural disease ( insufficient to kill the patient ) or vaccination. Vaccine types may be :-
A. Live attenuated ( weakened ) forms of viruses include the MMR ( measles, mumps and rubella ); or bacteria such as BCG for TB.
B. Inactivated – such as the ‘flu jab.
C. Detoxified toxins produced by a bug, such as for tetanus.
D. Extracts – such as pneumococcal vaccine, or from recombinant DNA ( hepatitis B ).
Of course there are “ contra-indications “ to vaccines, such as known hypersensitivity, weakened immune system, and pregnancy ; and side effects have to be considered before INFORMED consent is given.
PASSIVE immunity – gives immediate protection using plasma from immune individuals – preferably human immunoglobulins.
A. “ Normal “ ( pooled ) immunoglobulin is prepared from pools of at least 1000 donations of human plasma, for use in limited circumstances.
B. Disease-specific immunoglobulins are also prepared from pooled plasma of selected human donors with high levels of the antibody required – such as following exposure of an unimmunised individual to rabies. Rhesus-negative mothers may be given anti-D immunoglobulin.
Our knowledge of immunology is constantly improving. The immune system is complicated – a double-edged sword in that it efficiently rids the body of pathogens, cancer cells, and “ foreign “ agents … until it develops fault(s) or weakens with age.
Vaccination policies also change – to keep pace with mutating viruses like ‘flu and changing disease risks ; new knowledge and vaccine types ; and vary between countries reflecting disease patterns. Important diseases like dengue, malaria and HIV/AIDS STILL don’t have widely available vaccines, while tuberculosis needs a more effective one than BCG.