Microbiology & Parasitology in Nursing: Infection Control, Epidemiology, and Disease Prevention

Microbiology

The study of microorganisms, including bacteria, viruses, fungi, and parasites, and their effects on humans.

Pathophysiology

The study of the functional changes that occur in the body as a result of a disease or medical condition.

Antimicrobial resistance

The ability of microorganisms to withstand the effects of medications that once killed them or inhibited their growth.

Healthcare-acquired infections

Infections that patients acquire while receiving treatment for medical or surgical conditions.

Fungal infections

Infections caused by fungi, which can be more complex due to their unique characteristics compared to bacteria.

Gram stain

A laboratory technique used to differentiate bacterial species into two groups based on the characteristics of their cell walls.

Gram-positive

Bacteria that retain the crystal violet stain used in the Gram staining procedure, appearing purple under a microscope.

Gram-negative

Bacteria that do not retain the crystal violet stain used in the Gram staining procedure, appearing pink under a microscope.

Human microbiome

The collection of microorganisms living in and on the human body, playing a crucial role in health and disease.

Infectious disease

Diseases caused by pathogenic microorganisms, such as bacteria, viruses, parasites, or fungi.

Epidemiology

The study of determinants, occurrence, and distribution of health and disease in a defined population.

Health technology assessment

The systematic evaluation of the properties and effects of health technology, including its direct and intended effects.

Surveillance and control

The ongoing systematic collection, analysis, and interpretation of health data for planning, implementation, and evaluation of public health practice.

Risk, screening, and prevention

Strategies aimed at reducing the likelihood of disease occurrence through early detection and intervention.

Infection

The replication of organisms in host tissue, which may cause disease.

Carrier

An individual with no overt disease who harbors infectious organisms.

Dissemination

The spread of the organism in the environment.

Epidemiologic triad

A model that describes the interaction of host, agent, and environment in the spread of infection.

Equilibrium state

A condition where the interactions among host, agent, and environment are balanced, indicating health.

Teeter totter model

A visual representation of the balance between host, agent, and environment in relation to health and disease.

Patient management

The process of planning and providing care to patients based on their individual health needs.

Infection control

Procedures and practices aimed at preventing the spread of infections in healthcare settings.

Disease transmission

The process by which an infectious agent is spread from a reservoir to a susceptible host.

Epidemiologist

Deciphers connection between the agent, host, and environment in disease transmission.

Imbalance towards the Agent

The agent having more ability to cause a disease in humans, exemplified by the 2021 coronavirus.

Imbalance towards the Host

The increased susceptibility of individuals to diseases, illustrated by the H1N1 flu virus.

Chain of Infection

A series of events that enable microorganisms to cause infections in a person.

Types of Carriers

Different classifications of individuals who can transmit diseases.

Convalescent Carrier

Individuals who have recovered from illness but can still transmit the disease.

Healthy Carrier

Sub-clinical cases that remain well during the infection stage and never develop symptoms.

Active Carrier

An infected individual who can transmit the disease.

Incubating Carrier

Individuals who can transmit the agent during the incubation period before clinical illness begins.

Communicable Diseases

Diseases transmitted from one person or animal to another, directly or indirectly.

Sporadic Diseases

Diseases that occur infrequently and irregularly within a population in a specific geographic area.

Epidemic Diseases

A sudden increase in the number of cases of a disease in a specific region over a short period.

Endemic Diseases

Diseases consistently present in a population or geographic area, with fluctuating cases over time.

H1N1 Flu Virus

An RNA virus that mutates frequently, requiring annual changes to the flu vaccine.

Transmission

Occurs when an agent leaves its reservoir or host through a portal of exit and enters a susceptible host.

Direct Contact

A mode of transmission where diseases are spread through physical interaction.

Vectors

Organisms, like mosquitoes, that transmit diseases such as malaria.

Contaminated Surfaces

Surfaces that can harbor pathogens and facilitate disease transmission.

Preventive Measures

Specific actions like isolation, masks, and hygiene practices required to control disease spread.

Environmental Factors

Conditions that can influence the emergence of epidemic diseases.

Immunization

A public health strategy to control sporadic diseases.

Public Health Programs

Initiatives that can prevent the reemergence of sporadic diseases.

Incidence

Depends on factors like environment, population immunity, and pathogen virulence.

Pandemic Diseases

Occurring in epidemic proportions across multiple countries, often worldwide.

HIV/AIDS, TB, Malaria

Collectively cause more than 300M illnesses and more than 5M deaths per year.

Common Modes of HIV Transmission

1. Sexual contact 2. Transfusion 3. Contaminated needles 4. Perinatal transmission.

Primary Prevention

Measures aimed at a susceptible population to prevent a disease from ever occurring.

Secondary Prevention

Emphasizes early disease detection in healthy-appearing individuals with subclinical forms of the disease.

Tertiary Prevention

Targets both clinical and outcome stages of a disease to reduce severity and associated sequelae.

Primordial Prevention

Risk factor reduction targeting the entire population, focusing on social and environmental conditions.

Quaternary Prevention

Action taken to protect individuals from medical interventions that are likely to cause more harm than good.

Example of Primary Prevention

Common activities include limiting risk exposure or increasing immunity of individuals at risk.

Example of Secondary Prevention

Papanicolaou (Pap) smear aimed to diagnose cervical cancer in its subclinical state.

Example of Tertiary Prevention

Rehabilitation efforts implemented in symptomatic patients to mitigate disease severity.

Example of Primordial Prevention

Improving access to safe sidewalks in urban neighborhoods to promote physical activity.

Example of Quaternary Prevention

Identifying patients at risk of overmedicalization and suggesting ethically acceptable interventions.

Mortality from 1918 Spanish flu pandemic

Over 20 million people were killed.

Target population for Primary Prevention

Healthy individuals.

Target population for Secondary Prevention

Healthy-appearing individuals with subclinical forms of the disease.

Target population for Tertiary Prevention

Symptomatic patients.

Target population for Primordial Prevention

Entire population.

Target population for Quaternary Prevention

Patients with illness but without the disease.

Role of Nursing and Allied Health

Proper communication to provide appropriate levels of prevention to the general public and patients.

Importance of Education for School Staff

Educating staff on the importance of providing prevention as an aspect of caring for students.