Unit 9: Diseases and Disorders:

UNIT 9: DISEASES AND DISORDERS: An infection occurs when living agents enter tissue, multiply there and damage the tissue. The General causative agents for disease include: 1. 2. 3. 4.

5. 6. 7. bacteria viruses fungus Rickettsia protozoan arthropods (acting as vectors) vermiform (various invertebrate worms)

STAPHYLOCCOCCAL INFECTIONS: (bacteria) Staphyloccocci are spherical gram positive bacteria about .5 to 1.5 miccrometers in diameter. They tend to form in irregular clusters like grapes Staphylococcus aureus is the most pathogenic of the staphylococci (forms golden yellow colonies, almost all pathogenic and produces coagulase for blood

clotting) S. Aureus common problem in hospital s due to being carried on the skin of patients, visitors and the danger of infection of surgical wounds or skin breaks is high . S. aureus is difficult to treat and is very resistant to many antibiotics..mainly due to resistance to penicillinase.

S aureous often enters the body via natural openings in the skin barrier, hair follicles ect, if through mouth (food poisoning) Antibiotics do not penetrate abscesses well, thus making the infection more difficult to treat, often draining pus from abscess is one of the first steps of treatmenttreat with penicillin or erythromycin. Staph infections on newborns includes

impetigo (vesicles on the skin rupture and crust over), or scalded skin syndrome ( lesions on the nose and mouth, then bright red area appears, within 48 hr the skin of palms and soles peels off in sheet when touchedserious illness) 30 to 50% health adults carry staph in their nose and 20% carry staph on their skin.. and the human immune system is good at combating staph infections ( most susceptible include infants, elderly drug users and immune impaired)

scalded skin syndrome The boils that Job scraped with broken pottery (Job 2:7-8) could only have been caused by staph STREPTOCCOCAL INFECTION: including flesh-eating bacteria

Streptococci are gram positive spherical bacteria with cells growing in chains. They are facultative anaerobes Many are nonpathogenic and occupy the mouth, gastrointestinal tract and upper respiratory systems. Some Streptococci are responsible for skin

infections and secrete several enzymes including hemolysins (damages RBCs) Impetigo is one disease caused by Strep infections (symptoms include: superficial skin infection, isolated pustules( round elevations full of pus) that become crusted and rupture Impetigo is one disease caused by Strep infections Strep also causes scarlet fever,

infections of the throat Steptococcus pneumonia most common cause of bacterial pneumoniaand also the cause of flesh-eating bacteria (necrotizing fasciitis ) S. pneumonia is highly resistant and emits an enzyme able to destroy the fascia, or tissue that binds skin to muscle at a rate of an inch an hourabout 1500-2000 cases in USA per year with fatality rate of 30% in otherwise healthy adults. necrotizing fasciitis

Jim Henson from muppets died of this bacteria in 1990 from a splinter cut on his finger (duration from time of splinter to death6 weeks)

PSEUDOMONADS (bacteria) Aerobic gram negative rods, widespread in soil and water, able to survive in any moist environment. Cause otitis externa (swimmers ear) Pseudomonas dermatitis causes rash outbreaks and is associated with swimming pools

Pseudomonas aeruginosa common and serious opportunistic pathogen in burn patients (esp 2nd and 3rd degrees), it is carried on flowers or plants sent by well-wishers, thus reason hospitals do not permit these patients to receive flowers. Treatment with antibiotics gentamicin and carbenicillin, (Silver sulfadiazine used in burn victims)

WARTS: viral Caused by Viruses that stimulate an uncontrolled but benign growth of skin cells, they can be transmitted from one person to another by contact. Medical treatment includes applying extremely cold liquid nitrogen to them, drying them with electric current, or burning them off with acid. Some skin or cervical cancers

associated with this papillomarivius. SMALL POX (VARIOLA VIRUS) During middle ages 80% of population expected to contract small pox Two basic forms of this disease: variola major (mortality rate 20%), and variola minor (mortality rate 1%) Transmission and progression is via respiratory route, the virus infect many internal organs before eventually moving

into the blood (viremia)this leads to infection of the skin and the production of more recognizable symptoms ( virus in epidermal layers causes skin lesions that house the virus) . Rameses V (1156B.C.) showed evidence of small pox rash,

Pocahontas (1617) died of small pox Last outbreak in the USA was in 1947, routine vaccinations for small pox were discontinued in the United States in 1971 when it was deemed that the vaccination posed a greater threat that did contracting Ali Maow Maalin

HERPES SIMPLEX: (VIRUS) Greek meaning to creep both types of herpes simplex viruses may spread to the brain and cause herpes encephalitis, type 2 = 70% mortality if untreated

About 90% of the population of the United States has been infected with the herpes simplex virus initial infection usually during infancy, and often subclinical. About 15% of the cases develop lesions known as cold sores or fever blisters (usually occurring in oral or nasal mucous membranes) these lesions heal and the infection subsides but recur when the infection strengthens again ( due to hormonal, emotional stress or drop in immune

system) Between recurrences, herpes simplex type 1 viruses are latent in the trigeminal nerve ganglia communication between the face and the central nervous system. Herpes simplex 2 virus is transmitted via sexual contact (lesions appear after incubation period of 1 week and cause a burning sensation, after which vesicles appear) urination can be painful, and walking

uncomfortable. ( vesicles heal in a couple of weeks and contain the virus)( location of vesicles in female: external genitals, males: base of penis) Herpes simplex 2 has latent periods and active periodsvarying per personit can cross placental barriers and affect fetusbirth is via c section to prevent spread of disease to baby if the disease has not spread thru

placenta There is no cure for genital herpes, however Acyclovir can be administered topically or orally. Shakespeare wrote of this unsightly curse in Romeo and Juliet: Oer ladies lips, who straight on kisses dream/Which oft the angry Mab with blisters plagues,/Because their breaths with sweetmeats tainted

are MEASLES (RUBEOLA VIRUS) Extremely contagious disease that spread by the respiratory route. Person with measles is infectious before symptoms appear, thus quarantines not effective Humans are the only reservoir for measles, although monkeys are also

susceptible. Law requires immunization for schoolvaccines being 95% effective. Development and progression of rubeola begins in the upper respiratory systemincubation period of 10-12 days, symptoms develop including sore throat, headache, and cough, followed by a papular rash appearing on the skin, lesions of the

oral cavity include Koplik spots ( tiny red patches with central white specks (helpful for diagnostics) on the oral mucosa opposite the molars Measles is extremely dangerous disease, especially in very young or elderly. (1 in 3000 cases fatal in infants, complications such as encephalitis occur, if at all, about a week after the rash appears) and can cause severe birth defects if an expecting mother contracts german measles SCABIES: arthropod

Infection of the human skin caused by the mite Sarcoptes scabiei, a parasitic arthropod. The disease is most common among school children and is also found in adults sometimes occurring as a nosocomial infection. The fingers, wrist, and elbows are the most

frequent sites of infection. The mite burrow into the skin and fill the tunnel with their eggs and feces. The eggs hatch, and new mites mature, mate and lay more eggs, perpetuating the life cycle.

Symptoms are the result of hypersensitivity reactions to the mites, and first occur 2 to 6 weeks after the initial infection. main symptom is itching especially when the skin is warm (ex in bed at night), a red raised lesions (erythematous papules) develop, which may become infected with bacteria through scratching. Diagnosis is made by examination of the skin with a 10X hand lens to id burrows, sometimes the mites can be picked out with a needle for microscopic examination. Treatment is by a topical application of gamma

benzene hexachloride (kwell) , with bedding and other personal objects sanitized. CUTANEOUS MYCOSES: (fungal) ringworms and athletes foot Fungi that colonized the hair, nails and outer layer of the epidermis are called dermatophytes and their infection are called dermatomycoses.

Dermatophytes grow on the karatin present in those locations, causing ringworms ( most being asymptomatic and removed for cosmetic reasons, named from Greek time period who believed the infection to be caused by worms) Dogs and cats are frequently infected with ringworms, as well as humans, if ring worms are in the groin region it is called jock itch, if on the feet it is

athletes foot Treatment is of a variety of topical medications including: miconazole, or clotrimazole, or with oral medication such as griseofulvin. Ring worms Athletes foot

CANDIDIASIS: Fungi The infection of the mouth with the fungi Candida albicans, which is not affected by antibacterial drugs, and will sometimes overgrow the mucosal

tissue when normal bacterial flora are suppressed. Newborns infants, whose normal flora have not yet established are often afflicted with candidiasis of the oral cavity called thrush Elderly, diabetics, and cancer patients can be afflicted with candida in the mucosal tissues of the vaginitis. Treatment is usually with a topical application of miconazole, clotrimazole, or nystiatin. Thrush CONTATGIOUS CONJUNCTIVITIS: pinkeye

bacteria Caused by Hemophilus aegytius, and is transmitted by hand contact or by flies. Treatment topical application of antibiotics (vary)

BACTERIAL MENINGITIS: An inflammation of the meninges caused by gram negative bacteria. Most patients suffering from any type of meningitis complain of headache and have symptoms of nausea and vomiting, convulsions and coma accompany the infection in many cases. Mortality rate varies with pathogen but is generally high for an infectious

disease todaymany survivors suffer from various neurological damage. Meningitis caused by different types of pathogens (viruses, bacteria, fungi, protozoan) There are 3 major types of bacterial meningitis: 1. 2. 3. meningococcal meningitis: caused by

Neisseria meningitides mortality rate 27% pneumococcal meningitis caused by Streptococcus pneumonia mortality rate 11% Hemophilus influenza mortality rate 43% most common Diagnosis is via analysis of cerebral spinal fluid and blood. Treatment is though a strengic regime of various antibiotics including Rifampin, penicillin and ampicillin

TETANUS: bacteria Causitive agent is Clostridium tetani, an obligate, anaerobic,endospore-forming, gram positive rod that is common in soil contaminated with animal feces. Symptoms are caused by an extremely potent neurotoxin (tetanospasmin) that is released upon the dath and lysis of the growing bacteria.( potent enough that the amount of toxin in the ink of one . could kill 30 people)

In normal muscle operations, one muscle contracts and the opposing muscle relaxes This neurotoxin blocks the relaxation pathway so that both the muscles contract, resulting in characteristic muscle spasms (if in the jaw lock jaw)

Mode of transmission is improperly cleaned deep puncture wounds, especially those with little or no bleeding, immunization is 100% effective and boosters of every 10 years maintains immunity..(DPT: diphtheria, pertussis, tetanus) Recovery does not confer immunity, an d about 560,000 babies die each year in Asia and Africa because their umbilical cords are cut with filthy instruments or the stump is packed with dirt. Tetanus

BOTULISM: Bacteria Caused by Clostridium botulinum, an obligately anaerobic, endospore-forming, gram-positive rod that is found in soil and many freshwater sediments. Ingesting the endospore usually does no harm, however in anaerobic environments, ex sealed cans, the microorganisms produces an exotoxin that is highly potent. Persons suffering from botulism undergo progressive flaccid paralysis for 1-10 days and

may die from respiratory and cardiac failure. Symptoms include nausea, but no fever, varying neurological safe) , difficulty swallowing ,general weakness, blurred Recovery does not confer immunity First described 1800s with blood sausage (blood and ground meat tied in pig stomach and incubated)

Botulin toxin not formed in foods with acidity below ph 4.7 ( ex tomatoes Mortality rate 25 to 40% Treatment relies heavily on supportive care,

antibiotics of no use because toxin is preformed Diagnosis by inoculation of mice with samples from patients serum, stool, or vomitus LEPROSY: BACTERIA Causitive agent Mycobacterium leprae, an acid-fast rod, with an optimum growth temperature of 30 C first isolated and identified about

1870. Sometimes called Hansens disease (avoid term leprosy) Two main forms: 1. 2. tuberculoid (neural) form characterized by regions of skin that have lost sensation and are surrounded by a boreer of nodules. Recovery sometimes

spontaneously lepromatous (progressive) form: skin cells are infected and disfiguring nodules form all over bodymucous membrane of nose affected, deformation of hand into clawed form and necrosis of tissue Both forms are spread by transfer of bacteria from lesions or inanimate objects exposed to lesion discharge Patients can be made noncommunicable

within 4-5 days by administration of sulfone drugs National leprosy hospital in Carville Lousiana reports about 200 cases a year. No vaccine for leprosy currently exists POLIOMYELITIS: Virus

Causitive agent: poliomyelitis virus Best known as a cause of paralysis, however, only about 10% of infected people develop identifiable symptoms, and the paralytic form probably affects less that 1% of those infected. Symptoms often asymptomatic or mild and may include headache, sore throat, fever and nausea. Humans only known natural host Primary mode of transmission is ingestion of water that is contaminated with feces containing virus

Occurrence more often in summer months in temperate regions Predilection sites: tonsils, lymph nodes of neck and ileum Diagnosis based on isolation of virus from feces and throat secretions Preventives: Salk vaccine and Sabin vaccine (more common in USA, less expensive and oral medication of orange flavored medicine)

RABIES: virus An acute infectious disease that usually results in fatal encephalitis. Causative agent is rabies virus (rhabdovirus) with a characteristic bullet shape Mode of transmission: bite of an infected animal, even the lick of such an animal can transmit the virus Bats probably transmit the disease among

themselves via inhalation of virus in guano ( documented cases of aerosol transmission to human who spelunker) Initially the virus multiplies in skeletal muscles and connective tissue then enters the peripheral nerves to the central nervous system where it causes encephalitis Symptoms: spasms of muscles of mouth and pharynx when liquid is swallowed, later stages just the sight of water causes spasms

(hydrophobia), final stages result from extensive damage to the nerve cells of the brain and spinal cord.Death inevitable 1. 2. 2 forms of the disease furious rabies: dogs highly excitable and

snap at anything within reach Dumb (paralytic) rabies: common in cats, only minimal excitability Treatment: Pasteur treatment (14-21 inoculations) and more recent human diploid cell vaccine (HDCV) (5-6 inoculations) Carriers: skunks 46%, bats 19%, foxes 10%, raccoons 10%,domestic animals 6%, dogs 6%.seldom in rabbits, squirrels or mice AFRICAN TRYPANOSOMIASIS: protozoan

Causes African sleeping sickness.. Causative agent Trypanosoma brucei gambiense, a flagellate that is injected by the bite of the tsetse fly (arthropod vector) Predilection site: blood

Symptoms: decreased physical activity and mental acuity, if untreated, the host enters a coma and death is inevitable. Treatment: drugs only affective when central nervous system is not affected,, drugs kill 99% but the remaining 1% becomes immune and multiply in the blood, new antibiotics are used and 99% are killed and the 1% become immune and rebuild the numbersmaking this a difficult condition to treat. NAEGLERIA FOWLERI: protozoan (amoeba)

A protozoan known to cause neurological disease. Symptoms: flu-like and death within one weak Etiology: the spore enters a broken mucous membrane, usually oral or nasal and the protozoan migrates to the brain where it

causes encephalitis like conditions and death. Most common victims are children who swim in ponds or streams. Only a few cases per year are reported, bur fatality rate is nearly 100% ANTHRAX: Bacteria

Common names include splenic fever, mrrian ( biblical term for anthrax), and charbon to name a few Anthrax is an acute infectious febrile disease of virtually all animals caused by Bacillus anthracis and is generally septicemia in nature but may be localized. Clinically characterized in a very short course (10-12 hrs) Generally appears in late spring and summer It is an aerobic, encapsulated rod, gram positive, not acid fast and oxygen is necessary for sporulation. Vegetative form is easy to kill with disinfectant, 12oF also kills this bacteria

Mode of transmission is: ingestion, inhalation, biting insect, Incubation period 1-14 days usually 36Prognosis: unfavorable Symptoms: increased pulse rate (rapid but weak), temp 104F, spleen enlarged, edema of lungs, Post mortal findings: rigor mortis is incomplete or completely absent 3 types of Anthrax:

1. 2. 3. cutaneous anthrax: characterized as pustular infection of skin, danger of septicemia Inhalation anthrax: endospores are inhaled, high fever, difficulty breathing and chest pain, septicemia and high mortality rate

Ingestion anthrax: ingest endospores and enters gastrointestinal tract KURU AND MAD COW DISEASE: Kuru occurs in isolated groups of cannibals who eat brains.

TAPEWORMS: Often asymptomatic Includes Taenia saginata: beef tapeworm, infestations begin with the consumption of undercooked beef, pork, or fish, adult worms can live in the intestines for up to 25 years and reach lengths of 6 meters (18 feet) Symptoms abdominal discomfort, psychological distress, when several feet pass through anus, flatulence

Drug of choice to eliminate the infection is niclosamide NEMATODES: Round worm infections including the following: 1. pinworms: Enterobius vermicularis. Which migrates out anus of human host to lay eggs, causing local itchingtreat entire house with

pyrantel pamoate, or mebendazole contraction is oral fecal generally children putting dirty fingers in mouth. 1. hookworms: Necator americanus. Attaches to intestinal wall and feeds on blood and tissue, can lead to anemia, or craving

unusual food such as soil or laundry starch, contact is bare skin in soil, treat with mebendazole. 1. 2. Ascariasis: Ascaris lumbricoidescan

grow up to one foot in length, live in intestinal tract and often diagnosed when adult worm emerge from anus, may be coughed up and swallowed allowing for migration to throat, lungs, or abdominal cavity. Effectively treated with mebendazole

CHINESE RESTRANT DISEASE: bacterial Aka Monosodium glutamate (MSG) which can cause chest pain, burning sensations, and feeling that your face is blowing up like a balloon.

The effects depend on how much MSG and vary from person to person but is a reminder that MSG is manufactured by Corynebacterium glutamicum, a cousin to the diphtheria germ TUBERCULOSIS: bacteria A

chronic bacterial disease caused by Mycrobacterium tuberculosis, characterized clinically by wasting of the body and granulomatous tubuncles. Often called white death, it is referred to in the BibleIt was the plague of the pharaohs Mode

of transmission: picked up by injection, inhalation, wound contamination Etiology: it is a slender, rod shaped obligate aerobe, stains gram positive, is acid fast, moderate resistance to heat, may stay alive

under moderate conditions 2-4 years Symptoms: gradual lose of weight , coughing, apnea, partial loss of appetite, unusual signs or symptoms depending on where the lesion is located, if body has enough resistance to the first tubercle, it may become walled off by scar tissue and never do any other damage to the body or spread further ( occurred with Marie Currie) Prognosis: unfavorable Incubation time: not definite time

By law cattle must me branded on the left jaw with a T to indicate TB positive animals and a reactor tag is placed in left ear ( red tag) Charles Dickens character David Copperfield died of tuberculosis. Well known personalities that suffered from TB included: King Tut, Edgar Allan Poe, Chopin, Robert Louis Stevenson, Adolph Hitler, Nelson Mandela

Treatment: today various drugs are used to treat TB including streptomycin, isoniazid (INH) and rifampin Charles Dickens character David Copperfield died of tuberculosis.

Well known personalities that suffered from TB included: King Tut, Edgar Allan Poe, Chopin, Robert Louis Stevenson, Adolph Hitler, Nelson Mandela YELLOW FEVER: arthropod borne virus Historically important because it was

the first such virus discovered and provide the first conformation that an insect could transmit a virus. The virus is injected into the skin by the mosquito ( Aedes aegypti is the vector) Symptoms: fever, chills, headache, backache, nausea, jaundice Treatment: none Incubation period: 4-18 days Vaccine: good for 6 years DENGI: virus Acute

but rarely fatal viral disease transmitted by the mosquito Aedes aegypti. Sometimes called breakbone fever, characterized by acutely high fever ,followed by a rash 2-4 days later (mainly on trunk, never on palms of hands or soles of feet) Generally will occur between Sept and November No specific treatment against the virus HOT VIRUS;


1967 3 factory workers became nauseated and began to vomit. Diarrhea set in eyes became severely bloodshot and a painful rash occurred ( due to blood clotting in thousands of capillaries), their throats became so raw they could not swallow and had to be fed intravenously

within 10 days they began vomiting and defecating bloodblood and Marburg virus gush in all directions If the virus lands on another human, the horrid cycle of infection begins again, killing about 25% of the people infected very lethal virus (only 3 documented outbreaks 1967,1976,1990

The virus looked like a short piece of yarn ( thus called filovirus) unlike the spherical shape of most viruses. Many scientist believe that this was an emerging virus ( one that had jumped into a new animal species. reason it was uncommonly deadly and the new host has never been exposed to the virus, and the hosts immune system has no

defense against the virus. both Marburg,and Ebola are Biosafety level 4 agents, kept under constant negative air pressure to ensure no escape of the virus as compared to HIV with is only a level 2 virus Ebola (river in Zaire)

First appearance 1976 (325 of 358 dead), kills 90% of its victims, it can attack and amplify itself in virtually any body tissue except bone and perhaps skeletal muscle. Characterized by seering headache, fever and muscle pain, then the bleeding starts (internal hemorrhaging and the bodys clotting factors begin, organs such as liver and spleen are transformed into hardened masses of coagulated blood and tissue, kidneys become so clogged with blood that they cease to function, blood flows into lungs, stomach and intestines death soon follows often

from shock , heart failure or lung congestion Ebola does in 10 days what it takes AIDs ten years to do it is a filovirus( shaped like a question mark), transmitted by air, but luckily not easily transmitted from human to human through casual contacthospitals where greatest miniepidemics occur. Antibodies have been collected and used to treat victims of hot virus diseases.

The blood of one nun, a survivor of Ebola, was repeatedly tapped for its Ebola antibodieswhen injected into a person during the early stages of Ebola fever, it sometimes proved beneficial CHAGAS: protozoan A protozoan disease of the cardiovascular system Causitive agent is Trypanosoma cruzi

, a flagellated protozoan Affects 40 to 50% of population in rural areas of S. America Reservoir include rodents, opossums, and armadillos Arthropod vector is the reduviid bug (kissing bug)that bites humans or animals around the lips the wound is scratched and the trypanosome enters the would Most damage is due to inflammation around

the wound but the nervous system can be affected ( loss of involuntary muscle contraction in esophagus and gastrointestinal tract Treatment is difficult in chronic progressive stage Nifurtimix drug of choice for treatmentno cure Some believe that Charles Darwin contracted chagas

on his voyage on the H.M.S. beagle He was known to have been bitten by the kissing bug MALARIA: protozoan Characterized by chills, fever and often vomiting and severe headache Causitive agent is Plasmodium falciparum, carried by the mosquito vector Anopheles

The sporozoite enters the bloodstream of bitten human within 30 minutes of bite, reproducing and moving to the bloodstream where it causes RBCs to rupture and the release of the mature merozoites.fever reaches 104F, sweating begins, fever subsides and patient feels normal until cycle begins again ( if 1% RBC infected then over 100,000,000,000 parasites in circula Treatment

is with quinine, or quinine derived antibioticsno effective control of malaria in sight LYME DISEASE: spirochete Named after location identified

(Lyme Connecticut) Number 1 tic-borne disease in USA Causitive agent is the spirochete Borrelia burgdorferi and the vector being a tic Ixodes pacificus Symptoms usually a rash appearing near bite site that expands out to about 15 cm ( bullseye appearance) followed by flu like

symptoms.if untreated the heart can become affected (possible requiring a pacemaker) and neurological symptoms can occur (face paralysis, meningitis, encephalitis) other symptoms include chills, headache, and muscle pain Treat with antibiotics but the later diagnosed the more difficult the treatment ROCKY MOUNTAIN SPOTTED FEVER: rickettsia The

number 2 tic-borne disease in USA This rickettsia is a parasitic Tick borne disease that is passed form one generation of ticks to another through their eggs (transovarian passage) Causitive agent is Rickettsia rickettsia , major tic vectors are Dermacentor andersoni (west) and D. variabilis (east) Symptoms:

About one week after bite a rash appears (often on palms and soles...which does not occur with viral rashes) resulting in leakage of blood into surrounding tissues, fever and headache follow,, death in about 3% cases Treat with Antibiotics such as testracycline and chloramphenicol very effective TICK PARALYSIS Called

ascending flaccid paralysis Possibly due to a toxin in the tic saliva, usually affects children Incubation period is 4-7 days, most cases in May and June Host wakes up paralyzed removal of tic results in full recoverylike a miracle Severity of case is according to how close to the brain the tic isdeath is rare Causitve agent: Dermacentor andersoni WHOOPING COUGH: bacteria

Causitive agent Bordetella pertussis, a small, nonmotile, gram negative coccobacillus, it is an obligate aerobe. The organisms does not invade tissues, but rather attaches to the cilia in the trachea and impedes their action, allowing mucus to accumulate. It primarily affects children and is quite severe Symptoms:

initial stage (catarrhal stage) similar to common cold, the paraoxysmal stage is characterized with persistent coughs so violent that it can break ribs, gasping for air between coughs causes a whooping sound, and occurs several times a day for 1-6 weeks. The Covalescence stage may last for months. This is a very long duration for a

respiratory infection, symptoms include high white blood cell count with diagnosis made from cultured throat swabs. Transmission is by inhaling pathogens expelled by coughing of infected patient Mild case requires no specific treatment Severe cases are treated with Tetracyclines and chloramphenicol..but only render the patient uncontagious Vaccines exist but have considerable

safety concerns (3.2 in 1 million result in neurological damage) INFLUENZA: virus Caused one of the worst plagues ever to afflict humankind in 1918 (Spanish flu also called Swine flu 40 million dead within months).It is pandemic So desperate the situation that Chicago police arrested people for

sneezing in public and San Francisco required people to wear surgical masks over their mouths and noses in pubic violators were arrested 1957 and 1968 had milder epidemics but Virologist are scared that before long another superflu will emerge saying we are already overdue Influenza does keep reemerging

(reason for flu shot each year)( only AIDS virus mutates faster that the Influenza virusboth being classified as RNA viruses) If the same flu strain appeared each year we would develop an immunity to it thus it mutates by changing its viral coat ever so slightly under a microscope it looks like a pasta

salad with twists of macaroni entwined with one another ( 8 twisted segments in all) Mutation is due to its ability to enter humans, pigs and ducks ( thriving in the digestive tract and allowing a mixing and blending of different strains.what emerges is a new strain each year) If the recombinant strain that is made

is capable of infecting and causing illness in humans, a new pandemic looms over the horizon Solution: keep ducks and pigs and humans away from one another as much as possible If different strains are not given the opportunity to co-infect a host, no superflu can emerge

However in Asian countries: hens are hung in cages above pigs, which feed on the hen droppings, the pig feces are used to fertilize fish ponds where ducks swim drink and release their waste the last few flu strains have been Hong Kong flu, Shanghai flu and Singapore flu Luckily there has been no epidemic strain since 1968. HANTAVIRUS: 1950s It was known as Korean hemorrhagic fever, later renamed

hemorrhagic fever with renal syndrome Was first discovered in the lung tissue of its natural host, the striped field mouse, in which it causes no illness Kidney involvement seemed to be a hallmark of the disease. When rats were tested in Baltimore, Philadelphia, New Orleans, New York and San Francisco the Seoul Korea Hantavirus turned up everywhere

(1980 due to importing goods) The American variety of hantavirus is a more deadly and silent killer, taking its toll unnoticed until late 1980s. It has been confirmed in cases of hypertension and chronic kidney failure at a frequency 5X greater than the general public. 1993 a hot hantavirus struck a Navajo

reservation in New Mexico a Navajo Indian passed away 5 days after his bride to be died both suffered mild flulike symptoms, then suffered severe respiratory distress Over a dozen more cases followed. One patient sat up in bed in the morning talking and eating breakfast was on a respirator by afternoon and was dead that night. Prevention: Control of rodent

population, wear mask when doing spring cleaning in garages or attics if mouse droppings are present.birds possible are carriers of hanta as well Treatment: poor but a vaccine against certain strains does exist PLAGUE: BACTERIAL Also called Black Death due to the characteristic blackish areas of skin caused by hemorrhages

14th century total population in Europe died of Plague Causitive agent is Yersinia pestis, a gram negative rod shaped bacteria transmitted from one rat to another by the rat flea Xenopsylla cheopis Is endemic in wild rodents especially ground squirrels, prairie dogs and chipmunks with the number of plague cases reported in the USA increasing

If the host dies, the rat flea seeks a replacementanother rodent or a human Virulence is due to the ability of the bacteria to survive and proliferate inside phagocytic cells rather than being destroyed. Symptoms: lymph nodes in groin and armpit become enlarged (swellings called buboes reason for name

bubonic plague), fever develops mortality rate 50-75% if untreated death within one week Particular danger is if the bacteria enters the blood and lungs (pneumonic plague) mortality rate 100%, even today this disease can rarely be controlled if not identified within 12-15 hours of onset of fever.death usually within 3 days high likelihood of airborne infections from

infected person Diagnosis is by a fluorescent-antibody testno vaccines are available except for persons likely to come in contact with infected fleas Prevention: control rat-based population via sanitation IN CONCLUSION: A wise man should consider that health is the greatest of human blessings, and learn how by his own thought to derive benefit from his illness Hippocrates

Fifty million people drink unfiltered water in America. Not surprisingly, waterborne microbes such as rotavirus, the worlds leading cause of diarrhea continue to infect, sicken and kill. Each year thousands of people die in the USA from infections by the familiar foodborne bacteria, salmonella and shigella.

Tuberculosis and AIDs are also on the rise in the USA, Canada and Europe. Jet travel has brought the human population(all 6 million +) together. It creates a melting pot for pathogens and for disease transmission. The extremely virulent viruses emerging from the rain forests (Ebola, Marburg, Lassa) are no longer isolated from the population.

The resurgence of tuberculosis has reminded us that diseases once vanquished can return with a vengeance To this point we have been blessed. The most common yet potentially dangerous bacterial infections (Step and Staph)remain susceptible to at least one antibiotic (vancomycin) and the most virulent or most lethal

infections (Ebola, AIDS, and Marburg) are not easily transmitted. But what if common pathogens become resistant to all antibiotics? What if AIDS or Ebola become airborne and easily spread as the flue or common cold?

Given the conditions that exist today, it is a scary thought. There is little doubt that the fourth horsemanpestilence has saddled up and is charging at us. The fight against pathogens is never over. To quote one epidemiologist We are

all in it together AND THE BATTLE CONTINUES!!!!!!

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    EDGE + HSCSD = ECSD EDGE + GPRS = E-GPRS 3G réseaux cellulaires / Master RSD Transport de données sans fil (voix, multimédia, autres) à haut débit sur la même connexion Possibilité de roaming au niveau mondial, et donc compatibilité...
  • London event - November 16th 2015 Older Men

    London event - November 16th 2015 Older Men

    Innisfree Allotments Project London event - November 16th 2015 Many of tenants live on low incomes- growing their own food helps with a limited budget People work at their own pace -some relapse back to depression or drinking, but the...
  • Psychology 3450W: Experimental Psychology Fall, 2019 Professor Delamater

    Psychology 3450W: Experimental Psychology Fall, 2019 Professor Delamater

    A socioeconomically matched group of children were identified who scored well enough on their pre-test indicating that they were ineligible for the Head Start program. BUT, the investigators monitored reading scores in 1st and 3rd grades, but matched the two...