Immunisation

“Immunisation is the most significant public health intervention in the last 200 years, providing a safe and efficient way to prevent the spread of many diseases that cause hospitalisation, serious ongoing health conditions and sometimes death.

Since the introduction of vaccination for children in Australia in 1932, deaths from vaccine-preventable diseases have fallen by 99 per cent, despite a threefold increase in the Australian population over that period. Worldwide, it has been estimated that immunisation programmes prevent approximately three million deaths each year.

Immunisation is critical for the health of children and the wider community. For immunisation to provide the greatest benefit, a sufficient number of people need to be vaccinated to halt the spread of bacteria and viruses that cause disease – a phenomenon called ‘herd immunity’. The proportion of the population that has to be immune to interrupt disease transmission differs for each vaccine preventable disease, but is around 90 per cent for most diseases. For a highly infectious disease like measles, this is up to 95 per cent of the population. This emphasises the need to stay vigilant and ensure high coverage rates are achieved, not only at the national level, but also at the local level.

In Australia, immunisation coverage rates for children are high, with over 90 per cent of children fully immunised at one, two and five years of age. This high rate of immunisation helps to maintain community immunity, especially for those who are too young to be immunised or those that are not able to be immunised for medical reasons. Without herd immunity, rare diseases will become common again, causing more illness and deaths.”

–  Australian Government- Department of Health Immunise Australia Program.

http://www.immunise.health.gov.au/internet/immunise/publishing.nsf/Content/introduction-ai

Diptheria:

• a vaccine preventable disease- an acute illness caused by Corynbacterium Diptheriae,
• toxins affect the respiratory tact, adrenal glands and myocardium,
• spread by droplets or direct contact with wounds,
• takes 2-5 days to show the disease.

Haemophilus Influenzae type B:

• Is a bacterium
• commonly found in the upper resp tract,
• infections can cause meningitis, epiglottitis, arthritis and pneumonia,
• takes 2-4 days to show infection,
• is a vaccine preventable disease.

Hep A:

• causes liver infections and damage,
• spread by foecal/oral route,
• the virus survives well on foods kept at room temp for several hours,
• plus through contaminated water,
• symptoms show about a month later- fever, lethargy, anorexia, nausea and vomiting, people can have dark urine, pale foeces, jaundice, itching and abdominal pain-
• is a vaccine preventable disease.

Hep B:

• Spread through sexual contact, household contact, intravenous drug use vertically ( from parent to child)- symptoms as per Hep A,
• most people recover from the acute infection but continue to harbour the disease.
• It is a vaccine preventable disease

HPV:

• the name of a group of viruses which cause warts, genital warts – precursors for cervical cancer,
• spread by skin to skin contact especially during sex, anyone who has ever had sex could have HPV- 80% of people have it by age 50
• Types 6, 11, 16 and 18 are vaccine preventable (types 16 and 18 linked with cervical cancer).
• Over 40 subtypes which can infect the genital area.
• Most of the time, it is a subclinical infection- only 1% of the time producing clinically significant lesions.
• Types 6 and 11 are responsible for 90% of genital warts
• 85% of anal cancers are HPV positive, 35% of oral HPV cancers are HPV positive, and this is increasing
• The vaccine is given in schools to 12- 13 y.o’s and as a catch up vaccine currently.
• There’s two vaccines – Gardasil ( quadrivalent- 6,11, 16 and 18)and cervarix

( 16 and 18).

• Australia was the first country to offer a mass vaccination program , initially to women
• The number of high grade cervical lesions in women under the age of 20 has already decreased by more than 2/3’s since the introduction of this program

Measles:

• A highly infectious disease caused by the Morbillivirus,
• the virus is droplet spread,
• symptoms take 10 – 14 days: rash, fever,cough, corhyza, conjunctivitis,
• complications include meningitis, pneumonia- sometimes fatal,
• is vaccine preventable.

Meningococcal:

• Is caused by the bacterium Neisseria meningitides,
• commonly found in the upper resptract- nose throat and trachea,droplet spread,
• takes 1- 10 days to show infection; fever,headache, meningism, rash.

Mumps

• Is a salivary gland infection caused by the Rubulavirus,
• the virus is droplet spread,
• takes a few weeks to show the infection,
• symptoms include swelling, fever, headache arthralgias,
• complications include infection to testicles ( infertility), ovaries, pancreas liver brain, hearing loss-
• is a vaccine preventable disease.

Pertussis ( Whooping Cough):

• Is cause by the bacteria Bordetella Pertussis,
• is highly infectious and most serious in babies-4 deaths of babies this year (2009)
• -are at greatest risk before getting there second booster,
• mum’s antibodies don’t provide adequate protection,
• droplet spread, can develop from URTI into a pertussis pneumonia,
• takes 7- 10 days to show disease,
• symptoms include cough and ‘whooping’ which can persist for months, complications include hypoxic encephalopathy,
• a booster is recommended for all adults planning a pregnancy.

The pertussis vax can now be given in the third trimester of pregnancy

Pneumococcal:

• cause by the bacterium S pneumoniae,
• some types are found in the upper resp tract,
• complications inc meningitis, sepsis, ear infections,
• most infections are vaccine preventable
• recommended for older aussie and ABTSI’s, plus you can immunize your child (Prevenar) at 2/12, 4/12, 6/12
• and those at risk get a 4^th jab at 12/12 and a pneumovax at 4 yrs.

Polio

• Is an acute illness following gastrointestinal infection by one of the three polioviruses,
• is spread through foecal oral route,
• can cause paralysis and meningitis,
• in 90% of cases the illness has no symptoms,
• if symptoms do occur they take 3 to 21 days to show and include headache, N&V, lethargy, back pain, paralysis, is a vaccine preventable disease.

Rotavirus:

• Is the most common form of severe gastro in kids causing half of all hospitalized cases,
• can be reinfected several times throughout your life,
• spread by foecal oral route, illness begins abruptly with N V & diarrhea- can lead to severe dehy,
• symptoms generally resolve within 3 to 7 days.
• Diarrhoea is one of the top two killers in kids less than 5 y.o worldwide- and rotavirus is the leading cause of diarrhoeal illness in kids worldwide.
• Kids are at a slightly increased risk of intersusseption in the week following the first dose of rotarix

Rubella. ( German Measles)

• caused by the Rubivirus,
• droplet spread,
• symptoms take 2-3/52 to show,
• symptoms are generally mild and may include a rash, lymphadenopathy, joint pain,
• complications are rare but include encephalitis,
• becoming infected in the first trimester leads to birth defects- deafness, blindness, heart defects,
• is a vaccine preventable disease,

Tetanus-

• is caused by the bacterium Clostridium tetani,
• spread from environment to open wounds,
• toxins enter nervous system causing muscle spasms, trismus (lockjaw), respiratory failure, death,
• tetanus is a vaccine preventable disease.

Varicella: ( Chickenpox)

• is a highly infectious virus,
• usually it is a mild infection but can be severe,
• symptoms take 10 – 21 days to show,
• the main symptom is a rash that turns into open wounds which crust over,
• complications include meningitis, encephalitis, shingles later in life,
• is a vaccine preventable disease

Modern vaccines provide high levels of protection.

Common side effectsof immunisations are pain at the injection site, fever and fussiness.

Vaccines have to pass rigorous safety standards in Australia before being approved by the Therapeutic Goods Administration. The approval process takes about ten years, and after release into the community there is regular review, there is regional and Australia wide surveillance systems- Rotashield was withdrawn from USA in 1998.

In the first year of life children normally get several diseases- ( coughs and colds, etc_ they also get several vaccines.