Vector Borne Disease
"Vector-borne disease" is the term used to describe an illness caused by an infectious microbe that is transmitted to people by blood-sucking arthropods.
Arthropods: Insects or arachnids that most commonly serve as vectors include blood sucking insects such as:
The term “vector” refers to any arthropod that transmits a disease through feeding activity. |
http://www.azdhs.gov/phs/oids/vector/diseases.htm
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Yellow Fever
Cause: The Yellow Fever is caused by an Aedes aegypti mosquito. This type of mosquito breeds even in the cleanest waters and thrives near human habitations. Both humans and monkeys are the most affected by this disease. When an infected mosquito bites either a human or monkey, the virus enters and circulated throughout the blood stream, then settles in the salivary glands. Mosquitoes transmit the virus back and forth between monkeys, humans or both. Up to 50 percent of people with the more severe form of yellow fever die of the disease.
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Places most affected: This is most common in areas of South America and Africa, affecting travelers and residents to that area.
Symptoms: During the first three to six days after you've contracted yellow fever — the incubation period — you won't experience any signs or symptoms. After this, the virus enters an acute phase and then, in some cases, a toxic phase that can be life-threatening.
Symptoms: During the first three to six days after you've contracted yellow fever — the incubation period — you won't experience any signs or symptoms. After this, the virus enters an acute phase and then, in some cases, a toxic phase that can be life-threatening.
Acute Phase: Once the yellow fever virus enters the acute phase, you may experience signs and symptoms including:
These signs and symptoms usually improve and are gone within several days.
Treatment: There's no specific treatment for yellow fever. But getting a yellow fever vaccine before traveling to an area in which the virus is known to exist can protect you from the disease. |
Toxic phase: Although signs and symptoms may disappear for a day or two following the acute phase, some people with acute yellow fever then enter a toxic phase. During the toxic phase, acute signs and symptoms return and more-severe and life-threatening ones appear. These can include:
The toxic phase of yellow fever can be fatal. |
Typhus
Causes: Typhus is a bacterial disease spread by lice or fleas. Without treatment, death may occur in 10 - 60% of patients with epidemic typhus. Patients over age 60 have the highest risk of death. Patients who receive treatment quickly should completely recover. Less than 2% of untreated patients with murine typhus may die. Prompt antibiotic treatment will cure nearly all patients. There are two types of bacteria, Rickettsia typhi or Rickettsia prowazekii. |
Rickettsia typhi causes murine or endemic typhus.
Symptoms: of murine or endemic typhus may include:
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Rickettsia prowazekii causes epidemic typhus. It is spread by lice.
Brill-Zinsser disease is a mild form of typhus. It occurs when the bacteria re-activates in a person who was previously infected. It is more common in the elderly. Symptoms: of epidemic typhus may include:
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Treatment includes antibiotics such as:
- Doxycycline
- Tetracycline
- Chloramphenicol (less common)
western equine encephalitis
Western Equine Encephalitis is a form of encephalitis that is contracted though the contact of living hosts. It was first isolated in California, 1930, from the brain of a horse with encephalitis. It's a large cause of encephalitis in the western parts of Canada and the U.S. WEE affects humans and horses, but can live in many types of mosquitoes, birds, and other species of mammals.
Symptoms
Are often unapparent, or mild unspecified illnesses.
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Treatment
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Eastern Equine Encephalitis (EEE)
Also called sleeping sickness, EEE is transmitted to humans by the bite of an infected mosquito. It is very rare in the US, with only an average of 6 six cases reported each year. Overall, only about 4-5% of human EEEV infections result in EEE. EEE is one of the most severe mosquito-transmitted diseases in the United States with approximately 33% mortality and significant brain damage in most survivors. That means that a third of people with EEE will die.
Symptoms: It takes 4-10 days after bite of an infected mosquito to develop symptoms, but some will be asymptomatic (will not develop symptoms).
EEEV infection can result in one of two types of illness, systemic or encephalitic.
Symptoms: It takes 4-10 days after bite of an infected mosquito to develop symptoms, but some will be asymptomatic (will not develop symptoms).
EEEV infection can result in one of two types of illness, systemic or encephalitic.
Systemic symptoms:
Abrupt onset characterized by:
This lasts 1-2 weeks, and the infected can make a full recovery if there is no central nervous system involvement. |
Encephalitic symptoms:
Symptoms of the encephalitis form has an abrupt onset in infants, and in children adults presents a few days after the systemic symptoms disappear.
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Treatment: There is no vacine or specific treatment for EEE. The syptoms are managed as best as the doctors can.
Picture source: http://upload.wikimedia.org/wikipedia/commons/0/00/Eastern_equine_encephalitis.jpg
Picture source: http://upload.wikimedia.org/wikipedia/commons/0/00/Eastern_equine_encephalitis.jpg
malaria
Malaria is a parasitic disease carried and transmitted by mosquitoes. Malaria kills about 1,000,000 people a year annually. It thrives in warm weather and is most prevalent in tropic and subtropic areas. Malaria became widely recognized in Greece around the 4th century BCE. All the clinical symptoms associated with malaria are caused by the asexual erythrocytic or blood stage parasites.
Treatment
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Lyme disease
Lyme disease is the most common tick-borne illness in North America and Europe, spread by Dear ticks when they feed. You are more likely to get Lyme disease if you spend time in a grassy/heavily wooded area, like you can see from the picture to the right.
Symptoms - Skin, joints, and nervous system are affected most often.
Early symptoms- (Within a month)
Later symptoms- (In some, several weeks or months after you have been infected)
Least Common symptoms- Several weeks after infection SOME develop)
Treatment: Antibiotics! Early illness is usually treated with medicines taken by mouth, for example, doxycycline (Vibramycin), amoxicillin (Amoxil), orcefuroxime axetil (Ceftin).
Anti-biotics will usually resolve rash within one or two weeks. Later illness may require intravenous drugs like ceftriaxone and penicillin G.
Unfortunately, there is no vaccine.
Risk Map source: http://media.npr.org/assets/img/2012/02/01/lyme_disease_risk_map_credit_maria-diuk-wasser-yale-school-of-public-health1_custom-c45208236e6cb18e67bebcfde2dc942fc434f6c2-s6-c30.jpg
Symptoms - Skin, joints, and nervous system are affected most often.
Early symptoms- (Within a month)
- Rash: A small red bump may appear at tick the tick bite, but this doesn't necessarily indicate Lyme. However, in cases of Lyme disease, the redness may expand and leave a bulls eye mark around the bite with a red ring surrounding a clear area. This rash is called Erythema migrans.
- Flue like symptoms: Fever, chills, fatigue, body aches and headache.
Later symptoms- (In some, several weeks or months after you have been infected)
- Joint pain: Severe joint pain, swelling. Knees will especially be affected, but pain can shift from joint to joint.
- Neurological problems: Weeks, months, or even years later you may experience an inflammation of the membranes surrounding your brain (meningitis) temporary paralysis of one side of your face ( Bell’s palsy), numbness or weakness in your limbs, and impaired muscle movement.
Least Common symptoms- Several weeks after infection SOME develop)
- Heart problems
- Eye inflammation
- Liver inflammation (hepatitis)
- Severe fatigue
Treatment: Antibiotics! Early illness is usually treated with medicines taken by mouth, for example, doxycycline (Vibramycin), amoxicillin (Amoxil), orcefuroxime axetil (Ceftin).
Anti-biotics will usually resolve rash within one or two weeks. Later illness may require intravenous drugs like ceftriaxone and penicillin G.
Unfortunately, there is no vaccine.
Risk Map source: http://media.npr.org/assets/img/2012/02/01/lyme_disease_risk_map_credit_maria-diuk-wasser-yale-school-of-public-health1_custom-c45208236e6cb18e67bebcfde2dc942fc434f6c2-s6-c30.jpg