M6 Flashcards
According to CDC, It is the spread of microorganisms from the infected stool of one person into the mouth of another; may occur via fecal contamination of food or water supply, or by hand-to-mouth transmission following inadequate hand washing after touching contaminated items.
Fecal Oral Route
Many pathogens that cause ____________ follow a “fecal-oral” route because they exit the source host in feces, are carried on inadequately washed hands to a vehicle such as food, water, or utensil, and enter a new host through the mouth.
gastroenteritis
The parasite ________ is transmitted orally by ingestion of food, water or vegetables contaminated by the feces that contain the infective stages of the parasite. A person infected with this will develop Amebiasis.
Entamoeba histolytica (cyst)
The bacteria ________ is spread by the fecal-oral route, which means it is shed in the stool of a host and enters the mouth of the next host by some means. Both humans and animals are infected by it.
Salmonella
It occurs through skin-to-skin contact, kissing, and sexual intercourse. Direct contact also refers to contact with soil or vegetation harboring infectious organisms.
Direct Contact
Mononucleosis is also known as?
Kissing Disease
TRUE or FALSE
infectious mononucleosis (“kissing disease”) and gonorrhea are spread from person to person by direct contact. Hookworm is spread by direct contact with contaminated soil.
True
Infectious mononucleosis, “mono,” “kissing disease,” and glandular fever are all terms popularly used for the very common infection typically caused by the ________, but other viruses can also cause the disease.
Epstein-Barr virus (EBV)
are these diseases spread through Direct or Inderect contact?
Chicken pox, common cold, conjunctivitis (Pink Eye), Hepatitis A and B, herpes simplex (cold sores), influenza, measles, mononucleosis, Fifth disease, pertussis, adeno/rhino viruses, Neisseria meningitidis and mycoplasma pneumoniae.
Direct contact
True or False?
Disease transmission can be prevented through frequent and thorough hand washing which is the best method to prevent disease transmission.
True
TRUE or FALSE
Irregular disinfection of frequently touched surfaces such as doorknobs, handles, handrails, restroom surfaces, medical instruments, computer keyboards, phones, office supplies and children’s toys are also good precautionary measures.
False; It shoud be regular
TRUE or FALSE
Using barriers such as gloves, masks or condoms can help avoid the spread of germs. Many infections can be prevented by keeping healthy with attention to good personal hygiene.
True
TRUE or FALSE
Diseases cannot be transmitted by a mechanical or biological vector, an animal (typically an arthropod) that carries the disease from one host to another.
False, It can
________ is facilitated by a mechanical vector, an animal that carries a pathogen from one host to another without being infected itself.
Mechanical transmission
TRUE or FALSE
a fly may land on fecal matter and later transmit bacteria from the feces to food that it lands on; a human eating the food may then become infected by the bacteria, resulting in a case of diarrhea or dysentery.
TRUE
Disease that results from an infection transmitted to humans and other animals by blood-feeding anthropods, such as mosquitoes, ticks, and fleas.
Vector borne
Examples of vector-borne diseases include, EXCEPT:
1. Dengue fever
2. Chicken pox
3. West Nile Virus
4. Lyme disease
5. Malaria
Chicken pox
TRUE or FALSE
Transmission over distances greater than one meter or 3 feet is called airborne transmission
True
Dust and fine particles known as ________, which can float in the air, can carry pathogens and facilitate the airborne transmission of disease.
aerosols
dust particles are the dominant mode of transmission of ________ to humans. It is found in mouse feces, urine, and saliva, but when these substances dry, they can disintegrate into fine particles that can become airborne when disturbed; inhalation of these particles can lead to a serious and sometimes fatal respiratory infection.
Hantavirus
When an individual coughs or sneezes, small droplets of mucus that may contain pathogens are ejected. This leads to ________.
direct droplet transmission
TRUE or FALSE
A wide variety of diseases are transmitted by droplets, including influenza and many forms of pneumonia.
True
Examples of Airborne Diseases, EXCEPT:
1. Tuberculosis
2. Lyme disease
3. measles
4. chickenpox
5. disseminated herpes zoster.
lyme disease
TRUE or FALSE
some diseases can have more than 1 mode of transmission, such as Chicken pox which is spread through direct contact and airborne. You have to consider the case-to-case basis of every patient.
True
also known as chronic diseases, are not passed from person to person. They are of long duration and generally slow progression.
Non-Communicable Disease (NCD)
These are Different Types of NCD’s, EXCEPT:
1. Cardiovascular Disease
2. Cancer
3. Respiratory Disease
4. Type 2 Diabetes
5. Pneumonia
6. Other NCDs
Pneumonia
TRUE or FALSE
NCDs account for 80% of all deaths globally.
False; It only accounts for 70% of deaths
A disease caused by a microorganism and therefore potentially infinitely transferable to new individuals
INFECTIOUS DISEASE
TRUE or FALSE
An infectious diseases may or may not be communicable, example of it is a disease caused by toxins from food poisoning or infection caused by toxins in the environment, such as tetanus.
TRUE
An infectious disease that is contagious and which can be transmitted from one source to another by infectious bacteria or viral organisms.
COMMUNICABLE DISEASE
A very communicable disease capable of spreading rapidly from one person to another by contact or close proximity
CONTAGIOUS DISEASE
Often referred to as a chronic disease, typically characterized by long term durations and slow progression. These diseases are combination of genetic, environmental, behavioral, and lifestyle factors.
eg., CVD, Cancer, Chronic respiratory diseases (COPD; asthma; interstitial lung diseases like sarcoidosis, idiopathic lung fibrosis, asbestosis, hypersensitivty pneumonitis) ; Obesity; Neurological diseases; Mental health disorders; Musculoskeletal disorders; Chronic kidney diseases
NON-COMMUNICABLE DISEASE-
ability of the agent to invade and multiply (to produce infection; the minimum number of particles or agents required to establish infection in 50- of a group of hosts of the same species (ID50 = infective dose – the estimated number of organisms or virus particles required to produce infection in 50% of normal adult humans exposed by a given route) ; depends on the following factors:
1. Viability
2. Portal of entry
3. Susceptibility of the host
4. Susceptible tissues
5. Body defense of the host
INFECTIVITY
capacity of an agent to induce/ cause/ produce disease which is clinically apparent in an infected host
PATHOGENICITY
ability of an agent to produce serious illness, measured in terms of fatality (Mnemonic: MaEL : abiLLLity to produce serious iLLness ; measured in terms of fataLLLity)
VIRULENCE
the ability of an agent to induce immunity, or to stimulate the host to produce defense mechanism; capacity to induce an immune reaction
IMMUNOGENECITY
ability to combine with products or effectors of the immune response
ANTIGENICITY
ability of the organisms to enter the host tissues, multiple and spread further
INVASIVESNESS
- A causative or etiologic agent
- A reservoir or source of the causative agent
- A mode of escape fr the reservoir (exit pathway/portal of exit)
- A mode of transmission fr the reservoir to the potential new host
- A mode of entry into the new host (portal of entry)
- A susceptible host
The Epidemiologic Chain
A. Interruption in any stage of the chain, disease will not develop
B. The reservoir and source are identical when transfer is direct from reservoir to host
C.Period of communicability – refers to the time durig which an infectious agent can be transmitted directly or indirectly fr an infected person to another person, from an infected animal to humas, or from an infected person to animals.
D. Span of time during which the organism escape fr the body
E. The period of communicability varies inversely with the degree of communicability
The Epidemiologic Chain
Stages in the natural history of disease and levels of prevention
Stages of Infection
Stages of Infection
Primary prevention: intended to reduce new occurrences (level of prevention) ; Exposure
Stage of susceptibility
Stages of Infection
Secondary prevention: intended to reduce duration and severity (level of prevention) ; Incubation period; Pathologic changes
Stage of subclinical disease
Stages of Infection
Tertiary prevention: intended to reduce complications and disabilities (level of prevention); Time of diagnosis
Stage of clinical disease
Stages of Infection
fourth stage?
Stage of recovery, disability or death
Level of Prevention
- immunization; hand hygiene; health education
Primary prevention
Level of Prevention
screening tests and early detection; laboratory tests
Secondary prevention
Level of Prevention
treatment and management; rehabilitation; preventing recurrence
Tertiary prevention
initial infection causing the illness
Primary infection
opportunistic pathogen has weakened the host immune system; typically caused by another pathogen or the same pathogen reactivating or re-infecting the host
Secondary infection
point in time when a pathogen enters the host
Exposure moment
point in time between when a person is exposed to a pathogen (such as virus or bacteria) and when they start showing symptoms of the infection
Incubation period
it refers to the time between infection and the appearance of symptoms or signs of infection in a person who has already been exposed to the pathogen; the pathogen may be present in the body, but is not actively causing symptoms, and the individual is not symptomatic; clinically silent inside the body without any noticeable illness in host before suddenly causing severe illness and acute infection
Latent period
period during which an individual is recovering from an illness or infection; it starts after the acute phase of illness when symptoms begin to improve; an individual is still in the process of regaining their health and strength
Convalescence period
it refers to the duration during which an individual is in the process of returning to their normal state of health after experiencing an illness; it signifies the complete return to a normal state of health
Recovery period
measure of the rate of speed a microorganism multiply ; the time it takes for a population of microorganisms to double in number during exponential growth.
Generation time
refers to the initial and typically the most intense stage of the infection when the pathogen is actively replicating and causing noticeable symptoms in the infected individual
Acute phase of infection
refers to the stage of the disease in which the infection persists in the body over an extended period, typically for months or even years. The chronic phase may have milder or intermittent symptoms or even be asymptomatic (unlike in acute phase where symptoms are often intense and noticeable)
Chronic phase of infection
Is a process of infection that begins when an agent leaves its reservoir through portal or exit and is conveyed by mode of transmission then enters through an appropriate portal of entry to infect a susceptible host
Chain of Infection aka Epidemiologic Chain
Is a process in which a favorable condition is required for microorganism to spread or transfer from resevoir to a susceptible host
Chain of Infection aka Epidemiologic Chain
Infectious (Causative) agent
Reservoir
Exit pathway
Means/Mode of transmission
Entry pathway
Susceptible host
COMPONENTS of the CHAIN of REACTION
Disease-causing microbes such as virus, bacteria, fungus, protozoa, and rickettsia
Infectious agent
Source or habitat of the agent of infection or place where the microbe could grow, survive & multiply which could be in humans, animals, food, water, soil or equipment
Reservoir
the route through which the infectious agent leaves the reservoir
Exit pathway / Portal of Exit
A way or manner wherein an infectious agent can leave the reservoir host which could be through secretions & exudates (blood, feces, or urine); common mode of exit: break in the skin, nose, mouth, anus
Exit pathway / Portal of Exit
Through airborne, direct (touching or kissing) or indirect contact (via contaminated objects or fomites), droplets (coughing or sneezing) , vector (insect, arthropod or animal) and vehicle (flood, water or drugs)
Means of transmission (can either be direct or indirect )
The way an infectious agent enters a host, which include body orifices, mucous membranes, and breaks in the skin
Entry pathway
Elderly, NB babies, Immunocompromised patients, unvaccinated,critically ill patients, malnourished patients, etc
Susceptible host (someone who is prone to infection/vulnerable due to a weakened immune system)
Categories of Infectious Diseases by Transmission Route
spread through respiratory droplets, like the flu or common cold.
Respiratory Infections
Categories of Infectious Diseases by Transmission Route
are diseases that are transmitted from an infected animal or human to another person or through a bite of a vector (like mosquitoes, ticks, flies or snails). Diseases like Malaria, Dengue fever, Lyme disease, Sleeping Sickness, Schistosomiasis
Vector-Borne Diseases
Categories of Infectious Diseases by Transmission Route
contracted through contaminated food or water, like cholera and salmonellosis
Foodborne and Waterborne Infections
Categories of Infectious Diseases by Transmission Route
spread through sexual contact, including HIV, syphilis and gonorrhea
Sexually Transmitted Infections (STIs)
Categories of Infectious Diseases by Transmission Route
Water contaminated with germs, chemicals, or toxins can lead to waterborne illness if you drink it, breathe it in, or it touches your skin, eyes, ears, or other mucous membranes
Water-borne diseases
Categories of Infectious Diseases by Transmission Route
Cryptosporidiosis (Cryptosporidium)
Cyclosporiasis (Cyclospora spp.)
Escherichia coli O157:H7 Infection
Giardiasis (Giardia)
Harmful Algal Blooms (HABs)
Hot Tub Rash (Pseudomonas Dermatitis/Folliculitis)
Legionellosis (Legionella)
these are?
Water-borne diseases
Categories of Infectious Diseases by Transmission Route
- sometimes called ‘water-scarce’ diseases because they are a problem if water supply is limited. They includefungal skin diseases such as ringworm, ophthalmic diseases (diseases of the eye) such as trachoma and conjunctivitis, and infections caused or carried by lice, mites, fleas or ticks.
Water-washed diseases
Categories of Infectious Diseases by Transmission Route
illnesses caused by microscopic organisms, like viruses and bacteria, that are ingested through contaminated water or by coming in contact with feces. If every person on the planet was able to practice safe sanitation and hygiene and have access to clean water, these diseases would not exist. Some common water-related illnesses arediarrhea, giardiasis, dysentery, typhoid fever, E.Coli infection, and salmonellosis
Water-based diseases
Categories of Infectious Diseases by Transmission Route
Transmission is via insects (lay eggs) harboring in water. Examples are Dengue fever, Malaria.
Water-related diseases
- Contact Transmission
- Droplet Transmisison
- Airborne Transmission
- Vector Transmission/Arthropod-borne
- Ingestion
- Direct inoculation
- Transplacental
These are?
Mode of transmission
Mode of transmission
(Direct or Indirect via contaminated articles)
Contact Transmission
Mode of transmission
in contact with mucous membrane directly or indirectly through sneezing, coughing, talking (Influenza, Meningitis)
Droplet Transmisison
Mode of transmission
(chicken pox/Varicella, PTB and measles)
Airborne Transmission
Mode of transmission
(Malaria, Dengue fever. Lyme disease, Zika virus, Chikungunya, Rocky Mountain spotted fever )
Vector Transmission/Arthropod-borne
Isolation or Quarantine?
separates the sick people with contagious disease from people who are not sick
Isolation
Isolation or Quarantine?
aims to separate and restrict the movement of people who have been exposed to a contagious disease to watch and see if they become sick. Quarantine helps to limit the spread of communicable disease
Quarantine
- Strict Isolation - eg., chicken pox, rabies
- Respiratory Isolation – eg., influenza, tuberculosis
- Protective Isolation – eg., patients with leukemia
- Enteric precautions – eg., patients with dysentery, hepatitis
- Wound and skin precautions – eg., herpes, impetigo, ringworm
- Blood precautions – eg., HBV, HIV/AIDS
these are?
Categories of Isolation
- Hand hygiene.
- Use of personal protective equipment (e.g., gloves, masks, eyewear).
- Respiratory hygiene / cough etiquette.
- Sharps safety (engineering and work practice controls).
- Safe injection practices (i.e., aseptic technique for parenteral medications).
- Sterile instruments and devices.
- Clean and disinfected environmental surfaces.
These are?
Standard Precautions (as per CDC)
are the second tier of basic infection control and are to be used in addition toStandard Precautionsfor patients who may be infected or colonized with certain infectious agents for which additional precautions are needed to prevent infection transmission.
Transmission-Based Precautions
Transmission-Based Precautions
use it for for patients with known or suspected infections that represent an increased risk for contact transmission
Contact precaution
Transmission-Based Precautions
use it for patients known or suspected to be infected with pathogens transmitted by respiratory droplets that are generated by a patient who is coughing, sneezing, or talking.
Droplet precaution
Transmission-Based Precautions
Use it for patients known or suspected to be infected with pathogens transmitted by the airborne route (e.g., tuberculosis, measles, chickenpox, disseminated herpes zoster).
Airborne Precautions
