Chapter 11 - Infectious Diseases in Humans Flashcards
What is a disease?
Condition that causes the body to function less effectively. Diseases produce specific signs and symptoms
What is the difference between a sign and a symptom?
A sign can be observed/measured (e.g. rashes, fever, coughing, vomiting) while a symptoms can be described/felt (e.g. headaches, fatigue, nasuea)
What are the 2 types of diseases?
Infectious (transmissible) and non infectious diseases (cannot spread)
What are infectious diseases caused by?
Pathogens (disease causing organisms). (e.g. bacteria, viruses). Infactious diseases include influenza, HIV and pnuemococcal disease
What are non infectious diseases casued by?
Inherited /malnutition / lifestyle choices /environmental factors. (.g. excessive alcohol consumption may cause liver cirrhosis, exessive fats casue CHD)
How are infectious diseases spead?
1)Through droplets in the air
2) Direct contact
3) Contaminated food and water
How do droplets through the air spread ID?
When a person coughs/sneezes, numerous tiny respiratory droplets are expleed. Droplets contian pathogens and anyone within a close range may breathe in teh pahogens and become infected. People are advised to wear a mask and practice social distancing.
How does direct contact spread ID?
1) An infected person may infect another person by exchanging bodiy fluids during sexual intercourse. STI, HIV are examples.
2) Can also be transmitted when breastfeeding, e.g. heptitis B and syphillis
3) Infected perso comes into contact with mucous membrane or an uninfaected person
4) Infeceted person comes into contact with uninfeted person
How does contaminated food and water spread ID?
Food and water can be contaminated by pathogens such as bacteria known as cholrea. Happens when food and water are not properly handle/stored. TO prevent
- hygenic food prep/stoage
- good personal hygiene
- maintian clean water supply
- proper sewage treatment
What are the difference in structures between a virus and bacterial cell?
Bacterial cell:
- Cell wall
- DNA
- Cell membrane, cytoplasm, ribosome
Virus:
- Protein coat
- DNA or RNA
- No cell membrane, cytoplasm or ribosome
What is influenza?
Disease that attacks respiratory system that cna lead to pneumonia.
Cause: Influenza virus
Transmitted by: Droplets in ait/ when person touches object contaminated ith virus and touches face
Signs and symptopns:
- High fever, headache, stuffy nose, cough, sore throat, muscle aches
How to reduce transmission of influenza virus?
1) Influenza vaccination annually
2) Avoid coming into close contact with people who have flu
3) Cover mouth and nose with tissue when coughing or sneezeing and dispose the used tissue and wear a mask
4) Wash hands with soap and water with disinfectant
5) Avoid touching eyes, nose, mouth
60 Take antiviral drugs
What is the pneumococcal disease?
Cause: Pneumococcal bacteria aka streptococcus pneumoniae
Transmitted by: Mainly respiratory droplets
Signs and symptoms: Fever, headache, vomiting, cough , cehst pain, rapid breathing
Hwo to reduce transmission of pneumococcuc bacteria
1) Pneumococcal vaccine
2) Prevntive antibiotics
3) ANtibiotics prescribed b doctor
What is a vaccine?
A vaccine contains an agent tht resembles a pathogen and prevents infecious dieases by simulating white blood cells to quickly produce antibodies when the pathogens invade
How do vaccines work?
Substances that trigge prodution of antibodies are antigens. They stimulate out WBC to produce antibodies against thhem. Proteins on surface of pathogens are antigens (e.g. bacteria, viruses). When a vccine which conains an agaent that resembles a pathogen, enters the body, it stimulates the WBC to produce antibodies htat destroy pathogens. They are specific in action and antibodies that destory one typ eof pathogen will be ineffective against aanotehr typ eof pathogen.
