Infectious Diseases Flashcards
Define Viruses
Viruses are small pathogens with a bit of genetic material (DNA or RNA, but not both) enclosed in a protein coat. They can’t reproduce independently and need to invade a living cell (plant or animal) to make copies of themselves. This invasion can harm or destroy the infected cell.
What is Filoviruses?
Filoviruses are virus types that resemble threads and are extremely lethal.
What is Hepatitis Viruses?
Hepatitis viruses cause various forms of liver infection, ranging from mild to life-threatening.
What is Herpes Viruses?
Herpes viruses establish permanent residence in cells and periodically cause flare-ups of symptoms.
What is Influenza Viruses?
Influenza viruses cause the flu and can change their outer protein coats dramatically, making individuals resistant to one strain susceptible to a new one.
What is Noroviruses?
Noroviruses, part of the calicivirus family, cause gastroenteritis in people.
What is Papillomaviruses?
Papillomaviruses may cause few symptoms in women and men but are associated with a rise in cervical cancer among younger women.
What is Retroviruses?
Retroviruses replicate their genetic material in a backward (retro) sequence compared to other viruses. The human immunodeficiency virus (HIV) is a retrovirus that causes acquired immune deficiency syndrome (AIDS).
What is Rhinoviruses and Adenoviruses?
Rhinoviruses and adenoviruses infect mucous membranes, leading to upper respiratory tract infections and colds.
What is Slow Viruses?
Slow viruses may not show early symptoms but can lead to fatal illnesses within a few years.
Can Antibiotics treat viruses?
Antibiotics are drugs that inhibit or kill bacteria and have no effect on viruses.
How do you treat viruses?
Antiviral drugs can’t completely eradicate a viral infection but can reduce its severity and duration. They are most effective when taken before an infection develops or in its early stages.
What is bacteria?
Bacteria are single-celled organisms with a firm cell wall and a flexible cell membrane enclosing cytoplasm. They possess all the genetic information (DNA) required for replication within a structure known as a chromosome.
Abundance of Bacteria
Bacteria are the most abundant microorganisms, and they can be either helpful or harmful. Many do not cause diseases and serve important roles in the body.
What is Friendly Bacteria?
Some bacteria, known as friendly bacteria, aid in digestion and perform essential functions in the body. However, even friendly bacteria can become problematic, leading to conditions like acne, urinary tract infections, and vaginal infections.
What is Harmful Bacteria?
Bacteria that harm the body do so by releasing enzymes that digest body cells or toxins that cause specific diseases, such as diphtheria or toxic shock syndrome.
What are Antibodies?
In response to bacterial invasion, the body produces antibodies, which are special proteins that attack and neutralize the bacteria.
What are examples of Bacterial Diseases?
Examples of bacterial diseases include tuberculosis, tetanus, gonorrhea, scarlet fever, and diphtheria.
What are Antibiotics (in relation to bacteria)?
Antibiotics are drugs that can kill bacteria without harming the body’s own cells. They work against specific types of bacteria.
How can you identify bacteria?
Specific bacterial strains can be identified through tests of blood, pus, sputum, urine, or stool samples.
Define Fungi
Fungi are eukaryotic organisms that vary in shape and size. They can be single-celled (yeasts) or form long chains of cells (moulds or mushrooms).
Describe Reproduction in Fungi
Fungi reproduce by releasing spores or by growing threadlike fibres.
Describe fungi Nutrient Absorption
Fungi lack chlorophyll and, therefore, do not make their own food from sunlight. Instead, they absorb nutrients from organic material, including human tissue.
Describe Uses of Fungi
Fungi can be beneficial as they produce natural compounds used in antibiotics, help bread rise, and contribute to beer brewing. They also play a role in breaking down dead plants and animals.
Describe fungi as a nuisance
Fungi can be a nuisance to humans by releasing enzymes that digest cells, leading to issues like athlete’s foot and infections in hair-covered areas like the scalp, beard, groin, and external ear canals.
What is Antifungal Treatment?
The treatment for fungal infections typically involves antifungal drugs.
What is Protozoa?
Protozoa are single-celled, microscopic animals that release enzymes and toxins capable of destroying cells or interfering with their function.
Protozoa- What is malaria?
Malaria is a serious and sometimes fatal disease caused by a parasite that commonly infects a certain type of mosquito which feeds on humans. People who get malaria are typically very sick with high fevers, shaking chills, and flu-like illness.
Protozoa- What is Amoebic Dysentery?
Protozoa can also cause amoebic dysentery, affecting many people worldwide. Treatment typically involves medical care, blood or fluid replacement, and drugs targeting the specific protozoan.
What is Giardiasis?
Giardiasis is the most common protozoa-caused disease in Canada, caused by microorganisms in human and animal feces. It’s a threat in places like daycare centers and among campers and hikers who drink contaminated water.
What are Giardiasis Symptoms?
Symptoms of giardiasis include nausea, lack of appetite, gas, diarrhea, fatigue, abdominal cramps, and bloating. While many recover without treatment, some may experience recurring attacks over many years.
What is the treatment for Giardiasis?
Giardiasis can be life-threatening, especially in small children and the elderly who are prone to severe dehydration from diarrhea. Treatment typically involves antibiotics.
What are Helminths?
Helminths are small parasitic worms that attack specific tissues or organs, competing with the host for nutrients.
What is Schistosomiasis?
Schistosomiasis is a major worldwide health problem caused by a parasitic worm that burrows through the skin and enters the circulatory system.
What are Tapeworms?
Infection with a tapeworm, another type of helminth, can occur from consuming undercooked beef, pork, or fish containing larval forms of the tapeworm.
Describe Transmission of Helminths
Helminths can be transmitted through various means, such as skin penetration or ingestion of contaminated food.
Describe Treatment of Helminthic Diseases
Helminthic diseases are typically treated with appropriate medications designed to target and eliminate the parasitic worms.
Define Reservoir
A reservoir is a place where any infectious agent can live, grow, and multiply. Reservoirs can include animals or insects, people, food, or water.
What are types of reservoirs?
Reservoirs can take various forms, such as animals, insects, humans, food, or water. They serve as sources where infectious agents can persist and proliferate.
Describe Animals and Disease Transmission
House pets, livestock, and wild animals have the potential to transmit diseases to humans. They can act as carriers of various infectious agents.
Describe Insects and Disease Transmission
Insects play a significant role in the transmission of diseases.
Houseflies can spread diseases like dysentery, diarrhea, typhoid fever, or trachoma.
Mosquitoes, ticks, mites, fleas, and lice can transmit diseases like malaria, yellow fever, encephalitis, dengue fever, and Lyme disease.
Describe Food-borne Illnesses
Every year, food-borne illnesses affect many Canadians, sometimes leading to fatal consequences. These illnesses are often caused by consuming contaminated food.
What role does bacteria play in food-borne illnesses?
Bacteria are responsible for approximately two-thirds of food-borne infections, making them a significant source of these illnesses.
What is E. coli?
Escherichia coli (E. coli) infections are a notable public health concern worldwide. Thousands of suspected cases of E. coli infection due to undercooked or inadequately washed food are reported annually. Symptoms can range from mild to severe diarrhea, sometimes with no blood to high levels of blood in the stools.
What is Pathogen Transmission by People?
Pathogens can be transmitted by people through various means, including the air, touch, or sexual contact. It’s important to be aware of these routes to prevent infection.
How do you prevent airborne transmission?
To avoid infection, stay out of the range of anyone who is coughing, sniffling, or sneezing, as these actions can release pathogens into the air.
How do you prevent contact transmission?
Prevent contact transmission by not sharing food or dishes with others. Carefully wash your dishes, utensils, and hands to reduce the risk of pathogen transmission.
How do you prevent sexual transmission?
To prevent sexual transmission of pathogens, it’s essential to abstain from sex or make self-protective decisions about sexual partners. Safe sex practices and awareness are crucial in this context.
What is Pathogen Transmission?
Microorganisms cannot move on their own and require a mode of transmission to go from a reservoir to a host. Direct and indirect human contact offers opportunities for disease-producing organisms to be transmitted
What is Vector-Borne Transmission?
When an insect or animal transmits a disease to a human, it is known as vector-borne transmission. This can play a significant role in the spread of infectious diseases.
Modes of Pathogen Transmission (5)
Direct Contact, Indirect Contact, Droplet transmission, Airborne transmission, and Common vehicle transmission
What is Direct Contact transmission?
Involves body surface to body surface contact, such as through blood-borne or sexual contact.
What is Indirect Contact transmission?
Occurs when a susceptible host contacts objects or hands that are contaminated, often via items like TV remotes, computer keyboards, or eating utensils.
