Chapter 13: Immunity and Infection By: Samantha Galloway, Gloria Martinez, Xavier Gonzales, Harrison Crowl, & Maria Bolanos

The Chain of Infection Infections: are caused by outside pathogens Transmitted by one person to another in steps. Step 1: Pathogen lives in its natural reservoir. Step 2: The pathogen has to exit the reservoir to transmit the infection. Direct transmission pathogens are passed on from person to person without intermediary. Indirect transmission the pathogens are transmitted by animals. Step 3: After being transmitted the pathogen has to find a way to enter the hosts body. The pathogens that have direct contact can a systemic infection. Once the pathogen is in the host it is matter variety of factors if the pathogen will infect the host or not.

The Bodies Defense System Physical and Chemical Barriers Skin Mucous membranes Body openings and the fluids that cover them are rich in antibodies and enzymes that breakdown and kill many microorganisms

The Immune System Immunological Defenders Different type of white blood cells Neutrophils- one type of blood cell that travels in the blood stream to areas of invasion attacking ingestion pathogens. Macrophages – “big eaters” take up the stations in the tissue as they act as scavengers devouring the pathogens. Natural Killing Cells- directly destroy virus-infected cells that have turned out cancerous. Dendritic Cells- reside in tissues, eat pathogens and activate lymphocytes

Epidemics and Pandemics Rapidly spreading disease/ health concern Pandemics Wide spread epidemic West Nile Virus Severe Acute Respiratory Syndrome (SARS) Rotavirus Escherichia Coli Hantavirus Ebola

Chlamydia Most common bacterial infection More prevalent in women Increases risk of HIV Causes PID in women No early symptoms Symptoms: Men: Painful urination; watery discharge; pain in testicles. Women: Painful urination; pain and bleeding with intercourse; increased vaginal discharge Treatment: Easily treatable with antibiotics

Gonorrhea Causes PID in women and arthritis, eye infections and rashes. Symptoms: Men: Discharge from penis; painful urination Women: No symptoms Treatment: Easily treatable with antibiotics

Pelvic Inflammatory Disease (PID) Occurs when women infected with chlamydia or gonorrhea do not receive medical aid Requires hospitalization 25% of women still experience long term affects Symptoms: Chills; pelvic pain; vomiting; fever Treatment: Antibiotics and then hospitalization

Human Papillomavirus (HPV) Most common STD Causes genital warts and genital cancers Highly contagious Incurable Vaccines available Symptoms: Genital warts Treatment: Treatment focuses on removal of warts

Genital Herpes Two types: HSV1 and HSV2 HSV1: HSV2 Symptoms: Occurs in childhood Easily fought off by immune system HSV2 Sexually transmitted Incurable Affects newborns 90% of people with HSV2 show no symptoms Symptoms: Lesions; swollen lymph nodes Treatment: No cure, but antibiotics lessen outbreaks

Hepatitis B (HBV) Inflammation of liver Fatal Transmitted through body fluids Effective vaccine Symptoms: Most never have symptoms Nausea, vomiting, chills, jaundice Treatment: None

Syphilis Once deadly Easily treated Infected develop a large ulcer called chancre Chancres have large amounts of bacteria Contagious Symptoms: Flu-like; rash If not treated leads to blindness; dementia; death

Other STDs Other STDs: Trich: BV: Crabs: Treatments: Trichomoniasis (Trich) Bacterial Vaginosis (BV) Pubic lice and scabies (crabs) Trich: Requires moist conditions Foul smelling discharge from vagina Increased risk of HIV BV: Fishy odor from vagina Crabs: Highly contagious Treatments: All of the above are easily treated with antibiotics