Quick questions on Prevention of non-infectious disease: HSC Biology Module 8

Education increases health literacy and changes behaviour. Effective programmes have clear messaging, repeated exposure, structural support (regulation, infrastructure) and target specific behaviours.

Screening tests asymptomatic people to detect disease early, when treatment is more effective and survival is higher.

Launched 1981 by Cancer Council Victoria with the Slip-Slop-Slap slogan; expanded to Slip-Slop-Slap-Seek-Slide. Targets skin cancer through sun protection. Backed by no-hat-no-play policies in schools, shade structures, and free sunscreen.

Tobacco cessation campaign with graphic warnings, plain packaging (2012), the Quitline, nicotine replacement subsidies on the PBS, and indoor smoking bans. Adult smoking rates fell from 35 percent in 1980 to under 11 percent in 2022.

Targets obesity, diabetes and cardiovascular disease through advertising on the harms of excess sugar and processed food. More mixed evidence on outcomes; obesity rates have continued to rise, suggesting education alone is insufficient.

Targets alcohol-related disease and trauma through warning labels, advertising restrictions and graphic campaigns.

Free biennial mammography for women aged 50 to 74. Detects ductal carcinoma in situ and small invasive cancers before they are palpable. Reduces breast cancer mortality by approximately 20 to 25 percent in regularly screened women.

Since 2017, replaced two-yearly Pap smears with five-yearly HPV testing from age 25. Combined with the HPV vaccine (introduced 2007), cervical cancer incidence has halved and Australia is on track to be the first country to effectively eliminate cervical cancer.

Free immunochemical faecal occult blood test (iFOBT) every two years for adults aged 50 to 74, mailed directly to homes. Detects adenomatous polyps and early bowel cancer. Has reduced bowel cancer mortality by approximately 15 to 20 percent in screened groups.

Within 48 hours of birth, blood is tested for over 25 conditions including phenylketonuria, congenital hypothyroidism and cystic fibrosis. Early detection allows dietary or hormonal intervention that prevents severe disability.

Not a formal national programme, but Cancer Council and GP-led skin checks identify melanoma early. Self-examination using the ABCDE rule (Asymmetry, Border, Colour, Diameter, Evolution) is taught widely.

Prospective parents' DNA is tested for recessive disease alleles - commonly cystic fibrosis, spinal muscular atrophy and fragile X (Medicare-subsidised in Australia since 2023). If both partners carry the same recessive allele, each child has a $\tfrac{1}{4}$ chance of being affected, and the couple can make informed reproductive choices.

During IVF, a few cells are biopsied from each early embryo and tested for the known disease allele. Only unaffected embryos are implanted, so a child who would have inherited the disorder is never conceived. PGD is used for serious single-gene disorders such as cystic fibrosis, Huntington's disease and beta-thalassaemia.

Combined first-trimester screening and non-invasive prenatal testing (NIPT) - which sequences fragments of fetal DNA in the mother's blood - detect chromosomal conditions such as trisomy 21 during pregnancy.

Rather than selecting embryos, gene therapy corrects the genome of an affected patient, usually by delivering a functional copy of the faulty gene inside a modified, harmless viral vector. Zolgensma delivers a working SMN1 gene to infants with spinal muscular atrophy; Luxturna treats an inherited form of blindness; gene-editing trials (CRISPR) are now curing some patients of sickle-cell disease and beta-thalassaemia. Gene therapy is the clearest "future direction for the cure" of single-gene disease.