SEXUALLY TRANSMITTED DISEASES

 

Bacteria  

     Gonorrhea—Neisseria gonorrhoeae—painful urination & discharge in males; often fewer symptoms in females

     Syphilis—Treponema pallidum—disease occurs in 3 stages—1st sore at point of entry; 2nd rash over skin & mucous membranes; 3rd lesions called gummas 

     Chlamydia infection--Chlamydia trachomatis—few immediate symptoms but can cause damage & scarring to internal reproductive organs of females

 

Viruses

     AIDS—HIV (human immunodeficiency virus)—loss of immune system function—can be transmitted by contact with infected blood or other body fluids, often but not necessarily by sexual contact

     Genital herpes—Herpes sjmplex virus type 2—recurring outbreaks of painful blisters on genitals

     Hepatitis B—chronic infection which may be spread by sexual transmission and other ways such as exposure to infected blood—liver damage, may be chronic

     Cervical cancer—HPV (human papilloma virus)—genital warts which sometimes lead to development of cervical & uterine cancer

 

Protozoa

     TrichomoniasisTrichomonas vaginalisvaginitis with purulent discharge in females; often no symptoms in males

 

AIRBORNE DISEASES

 

Bacteria

     Streptococcal pharyngitis (strep throat) & scarlet fever—Streptococcus pyogenes—high fever, sore throat, also rash if scarlet fever

     Tuberculosis—Mycobacterium tuberculosis—usually lung infection, sometimes bone or other tissue

     Legionnaires’ disease—Legionella pneumophila—severe pneumonia

     Pneumococcal pneumonia—Streptococcus pneumoniae--pneumonia

     Diphtheria—Corynebacterium diphtheriae—respiratory infection may result in formation of membrane composed of fibrin & dead cells that may block larynx & pharynx; heart affected by toxin

     Pertussis (whooping cough)—Bordatella pertussis--very severe cough that lasts for weeks

     Bacterial meningitis—Haemophilus influenzae, Neisseria meningitides, Streptococcus pneumonaie are common causative agents—infection of brain & spinal cord—often progresses rapidly and can be fatal

 

Viruses

     Colds—mostly coronaviruses & rhinoviruses    

     Influenza—respiratory symptoms, fever, aches

     Chicken pox—varicella-zoster, a herpes virus—vesicles on skin with itching but not pain—may recur later in life after lying dormant in nerve cells and is then called shingles—in this case vesicles occur but also severe pain in affected area

     Measles—fever & skin rash but may lead to complications such as enchphalitis

     German measles (rubella)—similar to measles but much milder disease—big danger is damage to fetus during pregnancy

     Mumps—inflammation & swelling of parotid glands

     Smallpox—variola virus—severe purulent lesions on skin but death due to damage to internal organs—has been eliminated as naturally occurring disease but concern over possibility of use in germ warfare

     Hantavirus pulmonary syndrome—severe pneumonia with fluid collecting in lungs—inhalation from droppings of infected rodents

     Viral pneumonia—respiratory syncytial virus (RSV) is most frequent cause

 

Fungi

     Histoplasmosis—Histoplasma capsulatuminhalation of spores, begins in lungs but may spread to almost any internal organ—often associated with bird droppings

     BlastomycosisBlastomyces dermatidisinhalation & lung involvement but may also cause skin lesions with abscesses & tissue destruction

     CoccidiodomycosisCoccidiodes immitis—begins with lungs but may spread to other organs

     Cryptococcosis—begins in lungs due to inhalation of spores—may spread to other internal organs including brain

 

FOODBORNE & WATERBORNE DISEASES

 

Bacterial food poisoningstoxin is already present when food is consumed

     Staphylococcal food poisoning—some strains of Staphylococus aureus—violent vomiting & diarrhea but relatively short-lived

     Botulism—Clostridium botulinumneurotcxin that blocks transmission of nerve impulses to skeletal muscle causing flaccid paralysis

 

Bacterial infectionsliving bacteria in body cause the trouble

     Salmonellosis—Salmonella—fever, nausea, diarrhea—usually lasts for several days—often associated with raw poultry

     Typhoid fever—Salmonella typhi—high fever & headache, diarrhea later in disease—can be fatal

     Campylobacter infections—fever, cramping, pain, diarrhea

     Helicobacter infections—Helicobacter pylori—cause of most stomach ulcers

     Cholera—Vibrio cholerae—violent vomiting & diarrhea with extreme fluid loss

     Vibrio parahaemolyticus—milder GI upset (but still bad) usually associated with shellfish

     Travelers’ diarrhea—strains of Escherichia coli that produce enterotoxin

     Shigellosis—Shigella species—bacillary dysentery

     ListeriosisListeria monocytogenes—mild flulike illness in most but can cause severe damage to fetus or miscarriage

 

Viruses

     Polio—headache, sore throat, fever, paralysis in small percentage of cases

     Rotavirus diarrhea—really bad “stomach virus”

     Norwalk gastroenteritis—regular “stomach virus” but still miserable

     Hepatitis A—nausea & diarrhea, liver is affected but not as severely as in hepatitis B

     Mononucleosis—Epstein-Barr virus—fever, sore throat, enlarged lymph nodes & spleen—spread in saliva

 

Protozoa

     Amoebic dysentery—Entamoeba histolyticadiarrhea & damage to intestinal wall—may be associated with produce such as lettuce

     GiardiasisGiardia lambliaprolonged diarrheal disease—often associated with drinking water from outdoor sources such as streams & ponds

     Tocxoplasmosis—can be contracted from undercooked meat or by inhalation & ingestion of oocysts from cat feces—damage to fetus

    

ARTHROPOD-BORNE DISEASES

 

Bacteria

     Plague—Yersinia pestisspread by fleas that have bitten infected rodents—can also be inhaled (pneumonic plague)

     Rocky Mountain spotted fever—Rickettsia rickettsii—most common in southeaster US—spreaed by tick bites—fever, rash and sometimes dadmage to internal organs—can be fatal

     Lyme disease—Borrelia burgdorferichronic infection of joints & occasionally heart—spread by deer tick

 

Viruses

     Yellow fever—spread by bite of Aeges aegypti mosquito—chills, fever, headache, nausea vomiting, liver damage causes jaundice & sometimes death

     Dengue fever—transmitted by same mosquito—fever & extremely severe muscle & joint pain (breakbone fever)

     West Nile fever—only recently occurring in US—fever, sometimes encephalitis that can be fatal, particularly in the elderly—spread by mosquitos

 

Protozoa

     Malaria—Plasmodium  species—spread by bite of Anopheles mosquito—chills & fever, anemia

     Chagas’ disease—Trypanosoma cruzispread by “kissing” bugs—damage to heart muscle or nerves that supply colon or esophagus

     African sleeping sickness—Trypanosoma brucei gambienseflagellates enter by bite of tsetse fly, migrate to cerebrospinal fluid—cause coma-like condition

 

DIRECT CONTACT

 

Bacteria

     Tetanus—Clostridium tetani—anaerobe that may establish an infection in puncture wounds & produce a toxin that leads to severe convulsions

     Gas gangrene—Clostridium perfringens—wound infection causes spreading necrosis of tissue; often fatal without proper treatment

     Stpahylococcal infections

     Tularemia—Francisella tularensisulcer at infection site—enlarged lymph nodes which often drain pus—can also be inhaled & this form may be fatal

     Anthrax—Bacillus anthracis—cutaneous form causes nasty ulcer; inhalation form highly fatal lung infection; GI form follows ngestion & is highly fatal also

     Brucellosis

     Pseudomonas infections

     Leprosy—Mycobacterium lepraerequires prolonged close contact for transmission—areas of skin lose sensation, nodules form—deformation of hands & face

 

Viruses

     Rabies—transmitted in saliva of infected animal (or person)—fatal encephalitis

     Warts—papilloma viruses—unlike genital warts, these are relatively harmless

 

Fungi

     Ringworm & other dermatomycosesMicrosporum, Trichophyton, Epidermophyton species

     Candidiasis—Candida albicans—causes infections of mucous membrane of vagina (vaginitis) or mouth (thrush)—usually occurs when bacteria in area are suppressed by antibiotics and normal flora fungi flourish