Caused by parasite › Transmitted by mosquito › Once injected into the human, the parasite grows...

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Transcript of Caused by parasite › Transmitted by mosquito › Once injected into the human, the parasite grows...

Caused by parasite› Transmitted by mosquito

› Once injected into the human, the parasite grows and multiples first in the liver and then the red blood cells.

Symptoms appear 7-10 days after infection

Patient will experience:› Fever, chills,

sweats, headaches, nausea, body aches, general malaise

About 1,500 cases reported every year in the U.S.› From travelers and/or immigrants› Malaria considered eradicated from U.S. in

1950’s. 3.3 billion people diagnosed worldwide

› Thrives in tropical and subtropical areas.

Multicelled organisms Contain polysaccharide – chitin Reproductive structures – spores Cause disease by interfering with

normal organ structure and function or by inflammation or allergy

Most pathogenic fungi are molds› Mold common in soil, air, water, dust

› Aspergillus mold is most common

Recent multistate fungal meningitis outbreak…

Picture: (CNN, 2012)

Inflammation of the protective membranes that cover the brain and spinal cord.

Many different types: fungal meningitis is NOT contagious but still serious.

Symptoms include:› Fever, headache, and stiff neck

Normally does not cause disease, but takes advantage of a weakened immune system› “opportunistic”

› Ex: Athlete’s foot fungal skin infection Infects about 10% of US population Topical creams prevent new growth, but don’t kill

fungi already there Often comes back

Prevention

Ex: Candida yeast infection› White or yellow curd-like patches

(colonies)› Thrives in moist & warm environments:

Mouth/throat, Digestive tract/anus, penis, vagina

› 75% of women will get a vaginal yeast infection in their lifetime.

Prions (Pree – ons) = Proteinaceous Infectious particles

Mutated prions cause:› Mad Cow Disease in cows and› Variant Creutzfeld-Jakob Disease (vCJD) in

people

An infectious agent composed only of protein

All known prion diseases affect the structure of the brain or other neural tissues by inducing abnormal folding of normal cellular proteins in the brain

Usually progresses rapidly and are currently untreatable and fatal

Prions can jump from one species to another, but easier among same species.› “Species barrier” somewhat protective› Cow by-products fed to other cows› In cows: Bovine Spongiform Encephalopathy

Symptoms› Loss of coordination› Dementia› Brain full of holes (sponge)› Death

Mad cow disease 1st identified in 1980s in Britain

217 people from 11 countries have contracted or died from vCJD to date (CDC)

› 170 in United Kingdom› 25 in France› 3 in U.S. – believed exposed in UK in 1980s

CDC: “The risk of getting mad cow disease from eating beef from European cattle is about 1 in 10 billion” (10/2003)

CDC: “The risk to human health from BSE in the United States is extremely low” (2007)

While the risk is small, it takes 10-20 years from infection to the onset of disease – so who really knows the risk??

USDA budget for 2007: cut back on cattle testing

Less than ½ of 1% (0.006) tested!

Public health control measures to keep infected meat out of the human food chain.› No downer cows (12/2003)› No cows fed to cows (1997)› Prohibition of certain cow parts in the

human food supply (2006) Ground beef a source?