Infectious Disease Control

Syllabus reference: Investigate procedures to prevent disease spread, including:
- Hygiene practices
- Quarantine
- Vaccination (passive and active immunity)
- Public health campaigns
- Pesticide use
- Genetic engineering
Learning intention: Describe the use of prevention methods in reducing infection spread.

Essential for preventing the spread of infections.
Examples of personal hygiene practices:
- Regular hand washing, teeth brushing, body cleaning, and clothes washing.
- Coughing and sneezing into the elbow.
- Avoiding sharing food and drinks.
- Using PPE (masks, gloves) when necessary.
Safe food practices:
- Disinfecting and sterilizing utensils and food preparation areas.
- Storing food in tightly sealed containers.
- Cooking meat to high temperatures to kill bacteria.
- Washing fruits and vegetables before consuming.
- Using separate cutting boards and utensils for raw and cooked foods.

Governed by federal, state, and territory laws and regulations.
Aim to protect the public, ensure healthcare safety and quality, and regulate the health sector.
Safe Drinking Water Act:
- Federal legislation regulating drinking water quality.
- Ensures safe and clean drinking water for the public.
Management of sewage and waste: Essential for public health and environmental protection.
Protection of the Environment Operations Act 1997 (NSW):
- Regulates waste disposal and pollution control.

Focused on preventing the introduction and spread of communicable diseases.
Quarantine Act 1908: Primarily governed quarantine measures before the pandemic.
Biosecurity Act 2015: Modernized framework for managing biosecurity risks.
Role of quarantine: Minimize the risk of exotic pests and diseases entering Australia to protect native flora, fauna, agricultural industries, the environment, and health.

Australia has strict animal quarantine practices.
Department of Agriculture, Water and the Environment (DAWE) oversees animal importation.
Rigorous process for importing pets:
- Obtaining an import permit from DAWE with specific conditions.
- Eligibility criteria based on species, health status, and country of origin.
- Certification by an approved veterinarian that animals are free from diseases and parasites.
- Quarantine inspection by biosecurity officers on arrival.
- Post-entry quarantine may be required, varying by species and country of origin.

Officers responsible for inspecting goods, cargo, and travelers entering Australia.
Enforce regulations related to importation, exportation, and prevention of illegal activities.
International arrival process:
- Passengers go through customs and immigration clearance.
- Present travel documents, arrival card, and brief interview with an immigration officer.
- Travelers declare items such as goods exceeding duty-free limits, cash over $10,000$ , and restricted items.

Generally less strict than international quarantine.
Implemented in response to biosecurity concerns or disease outbreaks.
Restrictions on the movement of certain fruits and vegetables to prevent pest introduction.
Fruit fly exclusion zone:
- Located in South Australia, Northern Victoria, and Southern New South Wales.
- Prevents infestation of the Queensland fruit fly.
- Fruit disposal bins at borders.
- Traps placed at the borders of the zone.

Contain a dead or weakened strain of a viral, fungal, or bacterial pathogen.
Induce a mild immune response, assisting the adaptive immune system in producing antibodies.
Body responds faster to fighting infection if previously vaccinated.
Most vaccinations require booster shots for secondary exposure and more antibodies.
Example: HB vaccination given at birth, then booster shots at 6 weeks, 4 months, and 6 months.
Immunity can be lost over time, especially without natural exposure.

Two phases of the body's immune reaction to a pathogen.
Involve immune cells and antibody production.
Primary immune response:
- Occurs when the immune system encounters a pathogen for the first time.
- Antibodies circulate in the bloodstream, binding to the pathogen.
- Characterized by a slow and gradual increase in antibody levels.
Secondary immune response:
- Occurs when the same pathogen infects the body again.
- Memory B and T cells recognize antigens quickly, initiating a faster response.
- Memory B cells differentiate into plasma cells, producing a large quantity of antibodies.
- Memory T cells are activated to coordinate the immune response.
- Results in quicker and stronger antibody production.
- Antibody levels peak faster, leading to more efficient pathogen elimination.
Illustrates the adaptive nature of the immune system.

Two ways the body acquires protection against infectious diseases.
Active immunity:
- Active natural immunity: Acquired when the immune system produces its own immune response after exposure to a pathogen.
- Artificial active immunity: Achieved through vaccination.
- Example: Vaccines for measles, mumps, rubella, or influenza.
- Usually long-lasting; memory cells provide rapid immune response upon re-exposure.
Passive immunity:
- Acquired when a person receives antibodies or immune components produced by another individual or organism.
- Natural passive immunity: Antibodies transferred from mother to infant through breastfeeding or across the placenta.
- Artificial passive immunity: Administration of pre-formed antibodies or immune components through injection of immune serum or monoclonal antibody therapy.
- Temporary, providing immediate but short-term protection.
- Antibodies gradually decline over time; no immunological memory develops.

Vital in raising awareness, promoting preventative measures, and encouraging behavior change.
Involve a combination of educational, informational, and behavioral change strategies.
Specific focus varies based on the nature of the infectious disease.
COVID-19 public health campaigns:
- Informed the public about spread, signs, and symptoms of COVID.
- Explained restrictive measures such as quarantining.
- Implemented a free vaccination program.
- Used the Service New South Wales mobile app for check-ins and contact tracing.
- Effective in reducing the incidence and prevalence of COVID-19.

Focused on controlling the spread of infectious diseases carried by vectors (mosquitoes, ticks, arthropods).
Pesticides reduce vector populations and interrupt disease transmission.
Includes various chemicals designed to control pests.
Mosquitoes as vectors for diseases like malaria, dengue fever, Zika virus, and West Nile virus.
Insecticides used to treat breeding sites and control mosquito populations.
Insecticide-treated bed nets and indoor residual spraying reduce adult mosquito populations.
DDT (dichloro-diphenyl-trichloroethane):
- A synthetic pesticide effective in controlling insect vectors, particularly mosquitoes.
- Played a significant role in malaria control efforts.
- Restrictions due to environmental and health concerns.
Aerial spraying: Often used to control insect pests damaging crops (caterpillars, aphids, beetles) and fungal diseases (rusts, molds).