Modern Service Public Health Practice consists of three parts:

(1)  The competent discharge of statutory functions such as communicable disease control and child protection and the discharge of duties under relevant legislation on public health matters eg AIDS, Port Health etc.


(2)  Providing Health Authorities/Boards with independent medical and epidemiological advice on how to review, plan, manage and evaluate healthcare services in order to meet a population's health needs.


(3)  Preventing disease and promoting good health on a wide canvas by working with other disciplines and multiple organisations; including local authority departments of social services, housing, environmental health and education, voluntary organisations and non-governmental organisations, private industry and individual members of the public.

  Public Health Service Departments are headed by a Director of Public Health. These individuals will have spent five or six years at medical school, will have done at least three years clinical medicine (and often much, much more); have spent five further years in higher specialist training in Public Health Medicine before their appointment as a DPH.

  Public Health Medicine is officially defined as:

"The art and science of preventing disease and promoting health through the organised efforts of society".

  All this is quite a challenge and a formidable responsibility. Of course, fortunately, we do not work alone. We manage a department of medical, nursing and other professional and administrative staff. We also work with many other professionals both within and without the NHS to promote and assist in improving health. Health improvements will only come from a wider combined push on improving NHS services and tackling the wider determinants of ill health like poverty, education and housing.

  Our core business combines medical management with the science of epidemiology. Unlike other doctors we don't generally see patients on a one-to-one basis. Our patients are the 500,000 or so people who live in our area. However, just like other doctors we:

—  make a diagnosis;

—  recommend treatment (usually develop a service or introduce a new one);

—  check that the treatment/service is working.

THE SCIENCE OF PUBLIC HEALTH MEDICINE

  Doctoring for a population, make up of a large number of people, needs some different skills than for the usual one to one doctor-patient relationship. Epidemiology and statistics are key to making a population diagnosis and evaluating the effectiveness of health services and non-health service interventions. Epidemiology is the study of the distribution of disease in populations. We generally look at:

who is most likely to suffer from a certain health problem (person);

where will a health problem be most prevalent (place);

when is it most likely to occur (time).

  We also study and try to identify the likely cause or causes of a disease or health problem (netiology).

  Looking at the:

effectiveness of health care interventions is also a frequent pastime (patient outcome).

  In these ways we can find out what the major health problems are for our area, their likely causes and design effective strategies to prevent or cure health problems. If neither of these is possible then services to care for people with chronic disease are needed.

  This approach is best explained by looking at some examples:

WHO

  People who are poor are more likely to die prematurely from heart disease and stroke than more affluent people. In contrast, more affluent women are more likely to get breast cancer.

  People from Asian subcontinent are more likely to suffer from heart disease and TB and people from Africa and the Caribbean are more likely to suffer from diabetes and hypertension.

WHERE

  Teenage pregnancy is much more common in some local areas. Children living in urban areas are more likely to be admitted to hospital with chest infections. Cryptosporidium infection and Salmonella Typhimurium DT 104 food poisoning are associated with private water supplies and farming in rural areas respectively.

WHEN

  Flu and childhood chest infections are more common in the winter whilst certain gastrointestinal diseases are more common in the summer eg Salmonella Typhimurium DT 104 and E. Coli 0157.

  Looking back in time, many diseases are on the decrease like heart disease, cervical cancer and tuberculosis. Some diseases or health problems are on the increase such as HIV, malignant skin cancer and teenage pregnancy. Treatments change this pattern eg less people now die of AIDS—more live long term with HIV or combination therapies.

WHEN

  The definitive causes of diseases and health problems need to be evaluated by thorough research which connects cause and effect. A good example here is Sir Richard Doll's sentinel work, which showed that smoking caused lung cancer.

  Deaths and serious injury from road traffic accidents are high in county areas compared with elsewhere. Human error is a causative factor in over 90 per cent of all road accidents.

  High levels of sulphur dioxide air pollution in London in the early 50s clearly contributed to increasing the death rate. This was known as "Winter Smog". The deaths were largely due to chest and heart disease.

EFFECTIVENESS

  Knowing a lot about the diseases which afflict local people is little help to them unless we can put in place effective health services and/or other interventions which will combat these health problems. The increasing enthusiasm for evidence-based clinical practice will do much to contribute to this goal. Research studies can help clinicians convert good intentions into treatments with proven benefit. A particularly good example of this is the ISIS II trial of thrombolytic drugs (clot busters) and asprin. These drugs combined dramatically improve survival after a heart attack. A Duty study showed that influenza vaccination halved the incidence of influenza in the elderly.

THE ART OF PUBLIC HEALTH MEDICINE

  Science is all very well in Public Health but it isn't worth doing unless we can persuade health care and other professionals to do things differently. Therein lies a key skill and personal attribute which is essential for all Directors of Public Health and their staff. Therein also lies a source of unpopularity. Other professionals and opinion leaders can understandably resent our perpetual enthusiasm for changing what they do. In striving to influence others we spend a lot of my time talking to them in meetings or one to one.

COMBINING THE SCIENCE WITH THE ART

  Sometimes a solution with a scientific basis is not what people want. It is often important to combine a rational model of decision making with the views and convictions of key stakeholders and the public. There are an infinite number of health problems on which we could focus our attentions. We choose which issues to focus on according to two parameters:

(1)  The size of a health problem paired with an effective intervention to alleviate it (the science).

(2)  The degree of stakeholder and public support for a change (the art).

IN CONCLUSION

  The FPHM/ADPH believe that my population focus on health adds an important perspective to that gained through one to one patient contracts. This contribution is delivered through a continuation of skills which include: medical, epidemiological, management, sociological and psychological.

  We hope we have fired your enthusiasm to improve health and health services through the organised efforts of society and brought to your attention the role that our organisations can play in that regard.