Malaria and Tick borne Illness: Schoenwald (exam 4) Flashcards
Malaria:
- Vector?
- how many forms are there?
- **Mosquito borne-Anopholes (female)
- **5 forms of protozoa-Plasmodium falciparum, vivax, ovale, or malariae-recently human infection with knowlesi
Malaria:
- how many infections/year worldwide?
- MC regions in the world?
- 350-500 million infections/year worldwide, approx. 1 million deaths
- Central and South America, India and Africa high incidence
Malaria:
- risk to travelers?
- epidemiology? (2018 cases)
- Dependent on area of travel and activity
- About 2000 cases annually in US–>Mostly in returning travelers
2018 cases:
- -228 million cases worldwide-transmission in Africa, Asia, Central and South America
- -93% from sub-Saharan Africa
- -Southeast Asia next at 3%
- -85% of all cases from Africa and India
- *405,000 deaths
malaria zones:
-Chloroquine-resisitant?
- subsaharan africa
- -areas of resistance to chloroquine have risen in the last few decades (dark regions on the map are chloroquine-resistant)
-central america, mexico, and parts of south america are the few places left that are chloroquine-sensitive**
Malaria transmission:
-MC mech. of transmission?
- Mosquito=MC*
- transfusion
- Organ transplantation
- Needle sharing
- Mother to fetus
Types of Malaria:
-5 recognized types of Plasmodium:
- Plasmodium falciparum–>most common in Africa 99.7% of cases
- Plasmodium vivax
- India and South America- Plasmodium ovale
- Plasmodium malariae
- Plasmodium knowlesi
- newly recognized in humans in 2014
- primarily in Southeast Asia-Malaysia
Malaria Life cycle
It takes the mosquito vector and the parasite, it makes it to the RBC’s in the end, but it’s housed in the liver first. Once it breaks out of the liver cell, it infects the blood stream (erythrocytes)
-there are different maturation phases
- immature= ring phase
- gametocytes (look like bananas in the RBC’s)= the mature form
- if the mosquito comes along and bites an infected person, the uninfected mosquito gets the gameocytes, and the cycle starts inside the mosquito
Take home message:
- Mosquito is the vector
- liver phases
- RBC phases (more mature infection)
Schoenwald’s take home message regarding malaria life cycle:
Take home message:
- Mosquito is the vector
- liver phases
- RBC phases (more mature infection)
Malaria–> prevention?
- Insect Repellent
- Anopheles mosquito nocturnal feeders
- Mosquito netting
- Permethrin containing clothes, tents, and other equipment (clothing lines that manufacture w/ permethrin– kind of a sticky material)
- Malaria chemoprophylaxis
(notes: anopheles come out at night but DON’T rely on that– so sleeping in mosquito nets may help and insect repelent)
Medications for Malaria Chemoprophylaxis (prevention side):
-**Chloroquine is standard! resistance issues? (where is it primarily used?)
- Used primarily for Central America (it’s not used as much anymore due to resistance)
- Generally well tolerated
- Weekly dosing through 4 weeks after return (start them 1 week prior to their travel leave)
-Note: chloroquine and Atovaquone are the MC used preventative meds
Medications for Malaria Chemoprophylaxis. (*Prevention side): list example medication
- *Atovaquone/Proguanil (Malarone)
- -**NO resistance to date
- -Very well tolerated
- -Daily dosing to continue through 7 days after return
Other Medications that can be used for Malaria Chemoprophylaxis: list 4
- doxycycline
- mefloquine (Lariam)
- Primaquine
- Tafenoquine(Arakoda, Krintafel)
Medications used for Malaria Chemoprophylaxis: doxycycline: --resistance? -tolerated? -dosing?
- Very little reported resistance
- Generally well tolerated-caution **sun sensitivity!
- Daily dosing to continue 30 days after return
(isn’t always the best med since it’s generally sunny areas)
Medications used for Malaria Chemoprophylaxis: Mefloquine (Lariam): -resistance? -S/E? -Dosing?
- Some resistance- primarily in Cambodia, Laos and Burma
- **Higher rate of side effects!! ie depression, confusion, night terrors, hallucinations
- Weekly dosing to continue through 4 weeks after return
- the only FDA med approved in pregnancy for tx of malaria
Medications used for Malaria Chemoprophylaxis: Primaquine: -used for? -Dosing? -what should you check for in the Pt?
Primaquine:
-Used for prophylaxis and antirelapse therapy (P vivax)
- Daily dosing to continue for 7 days after return
- **Check for G6PD-deficiency prior to administration-fatal hemolysis
(use this med in addition to another agent like Larium, but used for Pts who are traveling in areas with high incidence of P vivax)
Medications used for Malaria Chemoprophylaxis: Tafenoquine(Arakoda, Krintafel) -describe this agent -DO NOT give in pts with \_\_\_\_\_\_ -Dosing?
- Newest agent
- **Do not give in G6PD deficiency
- Start daily for 3 days prior to travel then weekly thru 1 week after return
(note: this one has different dosing)
Malaria: Signs and Symptoms
Usually cyclical:
- Fever
- Chills
- Headache
- Myalgias
Severe Cases:
- Seizures
- Confusion
- Renal failure
- Acute respiratory distress syndrome
- Coma
- Death
Diagnostic tools/Lab testing: Malaria
- what part of the hx is the most important?
- what is the *Gold standard test for Malaria?
-*Travel hx is very important part of diagnosing
Laboratory testing:
- -*Blood smears= Gold standard test!
- -It’s the MOST sensitive
- -It Determines species of malaria
- -Able to estimate percent parasitemia
- -*Best if done during episode of fever
Other diagnostic tools/labs for Malaria:
-rapid diagnostic tests?
Rapid diagnostic tests:
- Immunochromatographic methodology
- Detect malaria antigens
Limitations:
- -Cannot speciate
- -Less sensitive
- -Need to be confirmed by microscopy
- -Can stay positive for weeks beyond treatment
-*PCR–> More sensitive. And Referenced lab based
Malaria: tx?
-In the US what is gold standard?
In US:
**Atovaquone/Proquanil standard–>4 tablets po q day x 3 days
(preventative dosing is different than tx dosing!!)
Malaria and Pregnancy:
- infection potentially more ______ in pregnancy
- high rate of _____
severe
- -High rate of premature births, spontaneous abortions and stillbirth
- -Pregnant women should avoid travel to malaria zones
What are the 2 meds that are approved for malaria prophylaxis in pregnancy?
Chloroquine or Mefloquine
Which med is CONTRAINDICATED in pregnant Pts for malaria prophylaxis?
doxycycline**
Dengue Fever:
-is a _____ borne virus
mosquito
Dengue Fever:
- how many strains of this virus?
- Present in which areas?
4
-Present in Asia, Central and South America, Africa
Dengue Fever:
- Sx?
- tx? (what should be avoided)
- “bone break fever”
- Fatigue, fever, extreme muscle and body aches
- NO treatment
- Tx is supportive-AVOID Nsaids (because this can be a hemolytic/hemorrhagic fever)
West Nile Virus:
- vector?
- incubation period?
- Sx?
- Culex mosquito
- 3-14 day incubation
- Sx include: headache, mental status changes, fever, body aches, sometimes rash (about 1 in 150 infected develop serious illness) meningitis, flaccid paralysis unique
West Nile Virus:
- diagnosis with ____
- tx is?
- serologies IgG and IgM in blood or spinal fluid
- Treatment is supportive
West Nile Virus incidence:
- 2017
- 2018
2017: midwestern states had issues
2018:
2019:
2020: not much in the nation
Lyme Disease:
-caused by ____
- spirochete Borrelia burgdorferi
- Tick Ixodes ricinus “deer tick”
Lyme Disease:
-caused by ____
- spirochete Borrelia burgdorferi (=bacteria)
- Tick Ixodes ricinus “deer tick” (tick borne)
Lyme Disease:
- Sx? (*characteristic sx?)
- infection can spread to?
- incubation period?
Sx: Can cause dermatologic, rheumatologic, neurologic or cardiac abnormalities
- *Characteristic rash- erythema migrans- within 30 days of exposure
- Infection can spread to other parts of body
-Incubation 3-32 days
Tick Ex’s:
- female deer tick
- female dog tick
States at risk for Lyme disease
- northeastern part of US
- upper mid west
- west coast
Lyme Disease:
- Sx? (*characteristic sx?)
- infection can spread to?
- incubation period?
Sx: Can cause dermatologic, rheumatologic, neurologic or cardiac abnormalities
- *Characteristic rash- erythema migrans (“bullseye rash at site of tick bite)–occurs within 30 days of exposure
- Infection can spread to other parts of body
-Incubation 3-32 days
Stages Of Lyme:
how many stages?
3
Lyme Disease: Stage 1
- describe this stage
- what is present in 75% of Pts?
- Sx?
- Early infection
- Erythema migrans present (75%)
- Fever, myalgias, fatigue
Lyme Disease: Stage 2
Conduction abnormalities (5% some sort of AV block
Lyme Disease: stage 3
- describe this stage
- Sx?
Persistent infection, arthritis type symptoms, usually not previously treated
Lyme disease:
-diagnosis?
- Hx of exposure to ticks paramount
- Serologic testing often negative in 1st few weeks of infection–> ELISA followed by Western blot
Lyme Disease:
- tx in adults?
- tx in children <8 yrs of age?
-Doxycycline 100 mg po bid x 21 days
-amoxicillin in pregnant women
-Children <8 years of age:
Amoxicillin 50 mg/kg/day divided into 3 doses (q 8 hour dosing) x 14-21 days
Babesia:
- Vector?
- Sx?
- Carried by tick Ixodes scapularis
- Sx include: hemolytic anemia with fatigue, body aches, fever (may be abscent), splenomegaly and hepatomegaly
Babesia:
____ cross formation in RBC
maltese
-note: dogs can get babesia, they can get a hemolytic anemia, and require transfusions. It can be transferred from dogs to humans via a bite. this is a rare infection)
Babesia: tx?
- *Atovaquone 750 mg po bid and **Azithromycin 500-1000 mg daily x 7-10 days
(note: combo tx)
Spotted Fever:
- organism?
- vectors?
- in southeastern US?
- Rickettsia
- Tick or flea borne
- Worldwide occurence
- Rocky Mountain Spotted fever in southeastern US
Incidence in US RMSP
(rocky mountain fever)
- isnt really in our area even though it says Rocky mountain
- MC in southeastern US
Babesia:
Diagnosis?
- PCR
- Acute and convalescent sera
Babesia: Tx?
- Doxycycline 100 mg po bid x 14 days
- Doxycycline for kids and pregnant women (chloramphenicol also a consideration in pregnancy)
Babesia: Tx?
- Doxycycline 100 mg po bid x 14 days
- Doxycycline for kids and pregnant women with rickettsia (chloramphenicol also a consideration in pregnancy)
Anaplasma and Ehrlichia is a ____ ____ illness
tick borne
-**Morulae (inclusions in WBC)
Colorado Tick fever:
- organism?
- primary locations?
- viral
- Primarily in CO and ID
Morulae=
think Anaplasma!!!
Colorado Tick fever:
- type of infection?
- primary locations?
- viral**
- Primarily in CO and ID
Colorado tick fever:
- Sx?
- tx?
- Fever, rash, headache, **pain behind eyes, **low platelets
- Self limiting
- tx= Supportive care
Zika Virus review:
- Virus type?
- hx?
- diagnostic testing?
- tx?
- *flavi virus (same as west nile and yellow fever))
- knowing travel hx is good!!
- Sx:
- testing: PCR
- NO tx!
Zika virus:
- florida?
- South American/Caribbean outbreak?
-FL was having endemic cases for zika (and lot’s in texas)
- Outbreak about 5 years ago, now scattered cases only
- -Vaccines in development with one showing good results in Rhesus monkeys. -Studies are small.
Yellow Fever:
-tx?
- None
- Symptomatic care only-avoid NSAIDS as increase risk of hemorrhage
Yellow fever in Africa:
-middle region of africa requires vaccination (considered a yellow-fever zone)
Yellow Fever in South America:
- upper portion of south america (Brazil has had a HUGE outbreak in the last 4 years)
- brazil has caused a yellow-fever vaccine shortage
Yellow Fever:
-progression of disease?
Progression of disease= jaundice, hemorrhagic symptoms, shock, multi-organ failure—*death in up to 50% of these cases
(note: high death rate)
Zika Virus:
-CDC recommendations?
- HISTORICAL-CDC recommendation (Oct 9, 2016) men should wait 6 months to have intercourse after being in a Zika area
- Most current recommendation is from Aug 2018 and recommends 3 months of abstinence after travel in Zika zone
Zika Virus:
-What is the main risk?
In pregnancy!!! can cause Congenital birth defects–> ie Microcephaly (smaller cranial cavity)
Yellow Fever:
-vaccine?
- MUST have YF certificate to administer
- Live virus Vaccine should be AVOIDED in pregnancy
- and Precaution in age >60!!–> can cause Yellow Fever vaccine associated viscerotropic disease (YFV-AVD) (which is yellow fever-like symptoms following the vaccine that can cause death)
