Mr. Ramos
Health and Disease
Introduction to Health & Diseases
Health is the state of one’s body. Good health and bad health
Disease is anything that can lead to bad health. Diseases in humans are caused by viruses,
bacteria, fungi, plants, protists, human genetics, & chemicals.
Public HealthPublic health is the science that deals with
protecting and improving the health of people in a community.
How to helpTeaching people about disease & preventionProviding clean waterVaccinationFood & Drug safetyPromoting healthy habitsBlood Screening
Infectious DiseasesInfectious diseases can spread from one
organism to another.The organisms that cause infectious
diseases are called pathogens. A parasite is any organism that lives on or
in an organism and harms it. Some pathogens can release toxins to
harm. Toxins are poisons.
Infectious Diseases: VirusesViruses are tiny nonliving pathogens.
They can have DNA or RNAContain a protein coatThey are intracellular parasitesTheir life cycle can be lytic or lysogenicExamples: HIV, Flu, Ebola, Herpes, Rabies,
Dengue
Virus Life Cycle: Lytic & Lysogenic
Infectious Diseases: InfluenzaFlu is short for influenza. The flu is caused by an RNA type virus.Spread: sneezing, coughing, saliva. Symptoms: fever, headaches, sore throat,
coughing, severe body aches, and more. Treatment: plenty of rest, drinking water &
electrolyte beverages, pain and fever medication, antiviral medication.
Antibiotics are not needed.The flu constantl
y mutates, so you need a flu shot
each year
Infectious Diseases: HIV HIV stands for Human Immunodeficiency Virus HIV destroys the human immune system and leads to Acquired
Immune Deficiency Syndrome (AIDS). HIV is an RNA virus. Spread: sex, blood, semen, breast milk, sharing needles. Target: White Blood Cells (Helper T Cells) Symptoms: fever, swollen lymph nodes, headaches, diarrhea,
rash, cough, and many more. Some people are asymptomatic. Treatment: Cocktail of Antiretroviral drugs (no cure for HIV).
Infectious Diseases: HIVThe best and cheapest way to know if
someone has HIV is to check their blood for HIV antibodies.
ELISA is a blood test used to determine HIV antibodies.
Infectious Diseases: ParasitesDisease Parasite Spread BySleeping Sickness Trypanosoma brucei Bite of an infected
tsetse flyAmoebic dysentery Entamoeba histolytica Water or food
contaminated by body wastes or untreated sewage
Malaria Plasmodium vivax Bite of an infected Anopheles mosquito
Roundworm Ascaris lumbricoides Roundworm eggs that are consumed in contaminated food
Pinworm Enterobius vermicularis
Pinworm eggs that are consumed in contaminated food
Infectious Diseases: Chlamydia & Gonorrhea Chlamydia and Gonorrhea are caused by
bacteria. Chlamydia is caused by the bacterium
Chlamydia trachomatis.Gonorrhea is caused by the bacterium
Neisseria gonorrhoeae.Spread: they are sexually transmitted
infectionsTreatment: Antibiotics (people can be
cured)
Bacterial Gene Transfer: ConjugationBacteria can exchange information through
a process called conjugation. Conjugation is a way to transfer information
sexually (remember that bacteria reproduce asexually).
“Male” bacteria have are F+. They have a plasmid and a sex pilus.
“Female” bacteria are F-. They don’t have a plasmid or sex pilus.
Preventing Infectious DiseasesThree important ways to prevent infectious
diseases:Stay away from sick peopleGet vaccinatedPractice good hygiene
A vaccine is a weak or deactivated organism that is placed in the body to trigger an immune response.
Noninfectious DiseasesNoninfectious diseases are not spread from
one organism to another. Some noninfectious diseases are genetic,
so they can be passed down from parent to offspring.
Examples: Cystic fibrosis, Huntington’s disease, Sickle-cell anemia, Hemophilia, Diabetes, Cancer.
Noninfectious DiseasesEnvironment factors & one’s behavior can
increase the likelihood for developing these disease.
Drinking too much alcohol can cause liver cancer.
Eating too much sugar can cause diabetes.
Chemicals & polluted air, such as asbestos may cause lung problems.