infectious disease

Editor: Justin Healey
ISBN 978 1 921507 17 5
Year 2010

Price: $20.95

  

Infectious Disease
Volume 307, Issues in Society

Infectious diseases are major causes of illness, disability and death in many parts of the world. The recent swine flu pandemic has shown just how vulnerable we all are to communicable diseases which are capable of being transmitted from one person to another, or from one species to another. This book examines the various types of communicable diseases affecting Australians and how they are kept under control. Topics include: outbreaks, epidemics and pandemics; symptoms and treatments for Australia’s major infectious diseases including the common cold, bacterial and viral infections, the various types of influenza, pneumonia, mosquito-borne infections, food-borne disease, hepatitis, HIV/AIDS and sexually transmitted infections. This book also looks at vaccine-preventable diseases and gives an overview of Australia’s immunisation policy.

Glossary; Fast Facts; Web Links; Index



fast facts
FAST FACTS from this volume
  • In Australia and similar developed countries, infectious diseases are not among the leading contributors to the burden of disease. With improved sanitation, the introduction of antibiotics and immunisation programs, the impact of infectious diseases on Australia’s health has reduced markedly over the last century.
  • The burden of infectious diseases continues to be significant in Australia. Infections and immunisations account for about 7% of all GP consultations. Almost 4% of deaths annually are attributed to infection and a similar percentage of hospitalisations in 2005-06 were for pneumonia, urinary tract infections and gastrointestinal infections. Also, the potential for serous outbreaks continues to present a challenge in public health and requires planning and constant vigilance.
  • Deaths from infectious diseases have declined dramatically since the early part of the last century. In 1922, they accounted for 15% of all deaths, but by 2005 they accounted for a little over 1%. In 2005, there were just over 1,700 infectious diseases deaths, a death rate of 7.8 per 100,000 (age-standardised). Septicaemia accounted for the largest proportion of these (1,053 deaths) and the next most common was viral hepatitis (162 deaths).
  • The infectious diseases group was a relatively small contributor to the burden of disease in 2003, accounting for 1.7% of the total burden). The highest infectious disease burden was for older people, particularly for those aged 75 years and over. Most of the burden (69%) was because of premature death rather than years lived with disability.
  • Over 87,000 hospitalisations in 2004-05 were attributed to infectious diseases, a figure that has remained fairly steady in recent years. Intestinal infectious diseases were the largest group (38%). The largest number of admissions were for children, particularly those aged under 5 years.
  • Communicable diseases are those diseases capable of being transmitted from one person to another, or from one species to another. Two major groups of communicable diseases are certain infectious and parasitic diseases and acute respiratory infections which includes influenza and pneumonia as well as other acute upper and lower respiratory infections. In 2005 these two groups accounted for 3.7% of all deaths in Australia (4,859 deaths). Influenza and pneumonia accounted for 62% (3,034) of these deaths. Death rates increased with age, and were greater for males than females in most age groups. In 2005-06, there were 96,138 hospital separations in Australia with a principal diagnosis of infectious and parasitic diseases.
  • Over 200 different viruses cause colds. They can be lurking anywhere people have been. The virus spreads quickly through coughing, sneezing and touching things with hands and tissues that others then touch. Recent research says that if you smoke, or hang around with people who smoke, you are more likely to catch more colds and they can last longer. Although it’s called a cold, being cold doesn’t cause colds.
  • In 2008 the total number of reported sexually transmissible infections (STIs) in Australia was around 70,000 – including HIV, the virus that can cause AIDS. The number may even be much higher as many people who have had unprotected sex haven’t been tested. STIs are particularly common among young people aged between 15 and 29 years who make up about three quarters of reported STIs.
  • An influenza pandemic is a disease outbreak that occurs when: a new strain of influenza virus emerges to which no-one is immune; the virus causes disease in humans; the virus is spread easily between humans.
  • In the absence of immunity, a new influenza strain could spread rapidly, causing epidemics or pandemics, infecting large numbers of people with possibly fatal results. A pandemic or worldwide outbreak of a new influenza virus has the potential to infect 25-30% of the world’s population. An influenza pandemic will be unlike any disaster we have experienced in recent times. It will arise quickly and may occur in several waves; lasting several months or more.
  • In the twentieth century, the world experienced three influenza pandemics: the Spanish flu (1918), the Asian flu (1957-58), and the Hong Kong flu (1968).
  • There are three main types of influenza virus: A, B and C. Type A strains of influenza virus can cause severe illness and are the only type to have caused human pandemics. The H5N1 strain (‘bird flu’) is a type A influenza virus. Type B strains cause sporadic human cases and small-scale outbreaks. Type C strains only rarely cause human infection and have not caused large outbreaks.
  • In general, influenza viruses are spread in two ways: respiratory droplets from an infected person’s coughs or sneezes (these droplets generally travel less than one metre); and touching contaminated surfaces (including hands) and then touching your mouth, nose or eyes.
  • There is little doubt that we are long overdue for another flu pandemic. It is 40 years since the last flu pandemic and history suggests that some time in the next few years we will experience another. The emergence of infections such as SARS, bird flu and swine flu underscores that mutation and change are facts of life, that microbes change in accord with alterations in their environment and in their host, and that our health is often a delicate balance between people, wild and domestic animals, and the microbial world.
  • Immunisation protects people against harmful infections before they come into contact with them in the community. Immunisation uses the body’s natural defence mechanism – the immune response – to build resistance to specific infections. Immunisation helps people stay healthy by preventing serious infections. The diseases which can be prevented by routine childhood immunisation are included in the National Immunisation Program (NIP) Schedule.
  • Medicines known as antivirals may have some effectiveness in preventing the development of infection in people exposed to the influenza virus. When used as a treatment, antivirals can reduce the duration of symptoms and illness.
  • A vaccine that provides protection against a pandemic virus can only be developed after the new virus strain appears, and therefore may take several months to produce.
  • The annual seasonal influenza vaccine protects against seasonal influenza viruses, but will not protect against a pandemic influenza strain. Seasonal flu vaccination can be administered to any person 6 months of age or over who wishes to reduce the likelihood of becoming ill with seasonal influenza. However, annual vaccination is recommended for people who are at increased risk of flu-related complications.