How do people become infected with pinworms?
by ingesting eggs or contacting contaminated bedding, food, or other items
Where do pinworms hatch? Where do they mature?
- hatch: in the small intestine
- mature: in the large intestine
Where are infections more common?
Worldwide, infections are most common in school or preschool age children
How many people are infected?
approximately 40 million
What happens at night if you have worms?
- At night, female worms exit the anus and lay eggs
- leads to intense itching and sometimes infection in the anal area
- sleep is often interrupted
How are pinworms found?
- may be spotted upon inspection of the anal area
- a sample is often collected by pressing a piece of tape to the skin around the anus
What are the medications for pinworms?
- over the counter medication Reese's Pinworm Medication
- oral medications will kill pinworms
How do you prevent pinworms?
- washing hands
- keeping fingernails short and clean
- cleaning bedsheets
How do humans become infected with hookworm?
hookworm larvae penetrate the skin, usually through the bottom of the foot
Where do hookworms move in the body?
move to the lungs, enter airways and are swallowed
Where do hookworms develop into adults?
the small intestine
How do hookworms stay in the small intestine?
the attach themselves to the lining of the small intestine with hooks
How many eggs do females lay a day? Where do they go?
- they lay thousands of eggs each day
- the eggs pass through the feces
What are the symptoms of hookworm?
- irritation at the site of skin penetration
- later, mild diarrhea/cramps
- anemic (not enough blood) from all the worms' bloodsucking
How long can hookworms live in the human body?
up to 10 years
What are the medications for hookworms?
- oral medications: more than 99% effective if given twice a day for 3 days
- problem is, its still common, because poor areas get the worms, and can't afford the medication
- Mebendazole is one of 3 medications used in humans
How do you prevent Hookworm?
- wearing shoes
- limiting swimming and washing in untreated water
How many people are infected worldwide with hookworm?
- over 900 million people
- occurs in poor countries
- infection is very rare in us
- mostly in tropical and sub tropical regions
How do people become infected with Guinea worm disease?
by drinking contaminated water
What happens afte guinea worms mate?
males die and females move throughout the body
How big can guinea worms get?
- inside the body, the can grow up to 3 feet
- biggest roundworm
Where do the guinea worms end up?
- near the surface of the skin
- usually the lower legs
- they can cause swelling and painful blistering sores
Where does Guinea Worm occur? how many are infected each year?
- only in africa
- about 100,000 people infected each year
What do sufferers of the worm blisters do which is bad?
to soothe burning, sufferers tend to go to water where blisters burst, allowing the worms to emerge and release millions of larvae
How can Guinea Worms be removed?
can be surgically removed over many weeks by winding it around a small stick and pulling it out a tiny bit at a time
How are humans infected with Ascaris?
after swallowing eggs from the soil that gets on the hands
Where do young ascaris worms go?
- they leave the intestines and travel through the body to the lungs
- the worms go up air passages to the mouth, are swallowed then return to the intestines to grow
Who usually gets ascaris?
usually a childrens disease in the US but a high % of adults in many other countries are infected with it
How big is the ascaris worm?
- second largest round worm
- ranges from a few inches to a foot long
How many eggs can the females lay? Where do they lay them?
Females can lay as many as 200,000 eggs in the intestines of the host
What are the symptoms of people with ascaris?
mild stomach pains and diarrhea
What can ascaris worms cause in the lungs?
What can ascaris worms cause in the intestines?
violent abdominal pain
How many people worldwide are infected with ascaris?
and estimated 650 million
Are there drugs for ascaris?
drugs are available to easily rid a person of ascaris
What will reduce your risk of infection?
good sanitary conditions
How do people develop Elephantitis?
when bitten by an infected mosquito
What do the elephantitis larvae do once they get into the body?
- they spread through the bloodstream (often for years)
- as they accumulate, they block circulation and cause fluid to build up in surrounding tissues
What are the signs of infection of elephantits?
escessively enlarged arms, legs, genitalia, and breasts
Explain the common antibiotic for elephantitis?
the common antibiotic doxycycline might be effective in treating lymphatic filariasis.
What happens to the elephantitis parasites when you take doxycycline?
- the parasites responsible for elephantitis have a population of symbiotic bacteria, wolbachia that live inside the worm and help it digest.
- when the symbiotic bacteria are killled by the doxycycline, the worm is killed as well
How many people does elephantitis worm currently affect?
120 million people
Where are people infected with elephantitis?
- 73 countries throughout the tropics and subtropics of Asia, Africa, India, and parts of central and south america
- no reported cases in US
Can you be cured from elephantitis?
recovery is possible and surgery sometimes helps but any elephantits that develops is permanent
What is Loa Loa?
African Eye Worm Disease
How do people become infected with loa loa??
- they can become infected with the larvae after being bitten by an infected mango fly
- --->another mango fly can bite a human, get the disease and give it to another person
Where do the loa loa worms go as adults?
- the worms move throughout the body causing painful swelling
- the worms often appear arount the eye where they can be easily seen
How long can adult loa loa worms live in the body
at least 15 years
Are there any drugs to kill the adult loa loa worm?
- no but they can be easily removed by a minor surgery
- --->surgery isnt affordable where it occurs, africa
Where does Loa Loa occur?
it is confined to the rainforest and swamp areas of west africa
How do people contract Trichinosis?
- eating raw or undercooked meat with cysts
- usually pork
what are cysts? what happens to them in the body?
- enclosure that the worm is in. hard.
- hatches in the intestines and the worms grow to adults
Where do the adult trichinosis worms go?
- they invade muscles including the tounge, heart, and diaphram
- can also go to the lungs and brain
What are the symptoms of trichinosis?
- abdominal pain
- muscle pain
- all of these when chewing, breathing, or using large muscles
Is there treatment for Trichinosis?
- no treatment if the wroms have invaded the muscles
- albendazole can be used if worms are still in the intestine
How do you prevent Trichinosis
- meat tested by the USDA is safe
- eating wild animals puts a person at risk
How many cases of trichinosis are reported each year in the US?
What are other names for flatworms?
How many people are at risk for schistosomiasis?
1/2 a billion people
How many people are infected with schistosomiasis?
1/4 of a billion people
What is schistosomiasis? What are schistosomes?
- schistosomiasis: the disease
- schistosomes: the fluke that causes the disease
Where are schistosomes found?
in fresh water
Where do schistosomes go in freshwater?
What happens after reproduction of schistosomes occurs in the snail?
larvae swim about seeking skin to burrow through
What happens once the schistosomes are under a humans skin?
- the larvae migrate eventually through the blood to the linings of either the intestine, bladder, heart, and/or liver
- in the linings they reproduce sexually and the females lay eggs
Why are schistosomes unique flukes?
they are dioecious, which means the male individuals wrap around the females
What happens after the female schistosomes lay eggs in the body
if the females are able to lay eggs, the eggs pass into the space of the intestine or bladder and are passed into a water body where they hatch and go to infect more snails
Is it common for the schistosome eggs to not make it out of the body?
yes, it happens in many cases
What happens if the schistosome eggs dont make it out of the body?
- they circulate the body
- sometimes the eggs have spines (for tearing through the linings of the intestine)
- --->this makes the eggs very dangerous as the circulate
What may the immune system try to do when the schistosomes invade?
may attempt to fight them, just making matters worse
What is the treatment for schistosomes?
- schistosomiasis is so unusual that there is only one drug
- praziquantel is widely in use
What is the effect if drugs (praziquantel)
- drug regiments result in curing the infection in 60-98% of cases and reduce egg burden in the remainder.
- dead eggs may continue to shed for months, but the treatment should slow/stop egg laying and granuloma formation
What are tapeworms?
- parasites of the vertebrae digestive tract
- anything with a vertabrae can get them
How many species of tapeworm are known?
What do tapeworms require?
almost all tapeworms require at least two hosts with a definitive host and an intermediate host
***explain the definitive and intermediate host deal with tapeworms
- the intermediate host is where it first goes, and it can be a vertebrate or an invertebrate
- --->an example is a cow
- the definitive host is where the worm resides and grows and must be an invertebrate
- --->an example is a human
- human eats the cow with the worm in it
Where is tapeworm most common?
where livestock such as cattle and pigs are raised in areas where human feces are not disposed of in a sanitary manner
What is another common source for tapeworm besides livestock?
certain species of freshwater fish
Where do tapeworm infections mostly occur in people?
infections tend to occur more frequently in areas of the world where the people regularly eat raw or undercooked beef, pork, and fish
****How are humans infected with tapeworm? what type of host can they become?
humans can become intermediate hosts by consuming shelled larvae in contaminated food
What may tapeworms do in an evolutionary unfamiliar environment?
they may encyst in inappropriate locations such as the brain which is often fatal
What part of the tapeworm actually attatches to the intestine lining
- the scolex
- you need to see this in your feces before you know you are cured of tapeworm
What is the other part of the tapeworm following the scolex?
- these can grow back if broken and keep growing making the tapeworm longer
What are the symptoms of tapeworm?
- abdominal pain
- loss of appetite
What has happened in some cases of tapeworm?
- they have multiplied and spread to other body organs
- ---> if this happens, overall health of the person may deteriorate rapidly because tapeworms that are no longer restricted to the intestine can cause damage to tissues and organs
What are the observed symptoms when tapeworm infection has moved beyond the intestines?
- neurological symptoms such as numbness or tingling of the face
- double vision
Are tapeworms male or female?
What is the medication for tapeworm?
- the doc may advise niclosamide (Niclocide)
- this drug is extremely effective as it is capable of destroying tapeworms rapidly, thus, people taking Niclocide tablets are likely to get rid of tapeworms within a short period of time
What are segmented worms?
earthworms and leeches... those types
What are leeches?
parasites that suck blood
What were the use of leeches in ancient times?
- leeches were used to treat everything from headaches to ear infections to hemorrhoids
- historians think Egyptians used leech therapy 3,500 years ago
- the treatments slowed and stopped and returned again in the middle ages and the 1800s
How are leeches used today?
- leeches are routinely used to drain blood from swollen faces, limbs and digits after reconstructive surgery
- they are especially useful when reattaching small parts that contain many blood vessels like ears where blood clots can easily from in veins that normal drain blood from tissues