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.