Infectious Disease Flashcards
Contact transmission: 2 types
direct contact:
indirect contact:
Name some diseases associated.
direct contact: HIV/ AIDS, Hepatitis, mono, staph, salmonella, giardia
indirect contact: contaminated inanimate objects or spread of respiratory droplets
Airborne transmission
Evaporated droplets capable of surviving long periods of time outside body.
Only a few diseases are capable:
TB
Varicella (chicken pox)
Rubeola (measles)
Enteric (fecal-oral) transmission:
organisms are found in feces.
Ingesting contaminated food or water.
Vector-borne transmission:
intermediate carrier (vector) such as a flea or mosquito transfers the organism.
Droplet transmission
Droplets don’t travel far.
Influenza, rubella (German measles), strep pneumonia, RSV, SARS (severe acute respiratory syndrome)
chain of infection:
Infectious agent reservoir or host portal of exit mode of transmission portal of entry susceptible host.
What is vertical transmission?
mother to fetus
May occur through the placenta
May occur during the birth process
Examples: HIV, rubella, herpes.
primary therapy for HIV infection includes 3 types of antiretroviral agents:
(And examples of each)
- protease inhibitors (PIs), atazanavir (Reyataz), ritonavir (Norvir), fosamprenavir (Lexiva), darunavir (Prezista), saquinavir (Invirase); nucleoside reverse
- transcriptase inhibitors (NRTIs), such as emtricitabine + efavirenz + tenofovir (Atripla), abacavir + zidovudine + lamivudine (Trizivir), lamivudine (Epivir), lamivudine + zidovudine (Combivir); nonnucleoside reverse
- Transcriptase inhibitors (NNRTIs), such as nevirapine (Viramune) and efavirenz (Sustiva)
Type A hepatitis
Causes, risk factors
Infectious or short-incubation hepatitis
On the rise in people with HIV infection.
No chronic form
Highly contagious
Usually transmitted by the fecal-oral route, commonly within institutions or families. Ingestion of contaminated food, milk, or water. Outbreaks of this type are often traced to ingestion of seafood from polluted water.
Type B hepatitis
Causes and risk factors
Serum or long-incubation hepatitis
Increasing among HIV-positive individuals.
Considered to be an STI because of the high incidence and rate of transmission by this route. Routine screening of donor blood for hepatitis B (HBsAg) has decreased the incidence of posttransfusion related cases but transmission via needles shared by drug users remains a major problem
Transmitted by the direct exchange of contaminated blood as well as by contact with contaminated human secretions and stools. Transmission also occurs through perinatal transmission.
Type C hepatitis
Causes and risks
Accounts for about 20% of all viral hepatitis cases
Type C hepatitis is a blood-borne illness transmitted primarily via sharing of needles by I.V. drug users, through unsanitary tattooing, and through blood transfusions. People with chronic hepatitis C are considered infectious.
Type D (delta hepatitis) Causes and risk factors
Confined to people who are frequently exposed to blood and blood products, such as I.V. drug users and hemophiliacs. It’s transmitted parenterally and less commonly, sexually.
Occurs only in those who have acute or a chronic episode of hepatitis B. Requires the presence of HBsAg.
Depends on the double-shelled type B virus to replicate. For this reason, type D infection can’t outlast a type B infection.
What is fulminant hepatitis?
Life-threatening.
Can happen in all types of hepatitis.
Develops in about 1% of patients.
Causes liver failure with encephalopathy, progresses to coma and commonly leads to death within two weeks.
(Can also be caused by high doses of acetaminophen or other medications)
Primary liver cancer may develop after infection with which kinds of hepatitis?
Hepatitis B or C
What illnesses can also occur as complications of hepatitis?
Pancreatitis, cirrhosis, myocarditis, pneumonia, aplastic anemia, transverse myelitis, peripheral neuropathy
Symptoms are similar for the different types of hepatitis.
What are some signs and symptoms in the prodromal stage?
Fatigue, anorexia, headache, arthralgia, myalgia, photophobia and N/V. Fever.
What are signs and symptoms of the clinical jaundice stage of hepatitis? (Occurs after prodromal stage)
1 to 5 days before the onset of clinical jaundice, dark urine and clay colored stool.
Clinical jaundice: pruritus, Abdominal pain, indigestion anorexia jaundice which can last for 1 to 2 weeks.
Rash or hives. Palpation reveals abdominal tenderness in RUQ, enlarged and tender liver possibly splenomegaly and cervical adenopathy.
Recovery phase of hepatitis
Generally lasts from 2 to 12 weeks. Sometimes longer with hep B C or E.
Symptoms are decreasing or have subsided. Decrease in liver enlargement.
Diagnostic tests for the different hepatitis types:
hepatitis profile is routinely performed. This study identifies antibodies specific to the causative virus, establishing the type of hepatitis:
Type A: Detection of an antibody to hepatitis A virus confirms the diagnosis.
Type B: The presence of HBsAg and hepatitis B antibodies confirms the diagnosis.
Type C: Diagnosis depends on serologic testing for the specific antibody 1 or more months after the onset of acute illness. Until then, the diagnosis is principally established by obtaining negative test results for hepatitis A, B, and D.
Type D: Detection of intrahepatic delta antigens or immunoglobulin (Ig) M antidelta antigens in acute disease (or IgM and IgG in chronic disease) establishes the diagnosis.
Type E: Detection of hepatitis E antigens supports the diagnosis; however, the diagnosis may also consist of ruling out hepatitis C.
Type G: Detection of hepatitis G ribonucleic acid supports the diagnosis. Serologic assays are being developed.
Liver biopsy is performed if chronic hepatitis is suspected.
Hep A treatment / prevention
Persons believed to have been exposed to hepatitis A virus and the household contacts of patients with confirmed cases should be treated with standard immunoglobulin.
Travelers planning to visit areas known to harbor such viruses should receive hepatitis A vaccine.
Hep B treatment/ prevention
Hepatitis B immunoglobulin and hepatitis B vaccine are given to individuals exposed to blood or body secretions of infected individuals.
The immunoglobulin is effective but very expensive.
In addition to its administration as part of the routine childhood immunization schedule, hepatitis B vaccine is now recommended for everyone.
Hep c treatment
There is no vaccine against hepatitis C, but it is usually treated with interferon alpha-2b (Intron A) and the more recently Food and Drug Administration–approved peginterferon alpha-2a (Pegasys).
General nursing interventions for hepatitis
Patient is advised to rest and combat anorexia by eating small, high-calorie, high-protein meals. (Protein intake should be reduced if signs of precomalethargy, confusion, mental changes—develop.)
With acute viral hepatitis, hospitalization usually is required only for patients with severe symptoms or complications.
Parenteral nutrition may be required for persistent vomiting.
Antiemetics (trimethobenzamide [Tigan] or benzquinamide) may be given to relieve N/V.
For severe pruritus, the cholestyramine resin (Questran), which sequesters bile salts, may be given.
Explain that the liver takes 3 weeks to regenerate and up to 4 months to return to normal functioning.
Advise patient to avoid contact sports until the liver returns to its normal size.
Instruct the patient to check with the physician before performing any strenuous activity.
Infectious Mononucleosis
Standard Precautions
Caused by the Epstein-Barr virus (EBV), a member of the herpes group.
Usually young adults and children, but some cases are so mild that the infection is overlooked.
SX: fever, sore throat, and cervical lymphadenopathy. It may also cause hepatic dysfunction
The prognosis is excellent, major complications are uncommon.
Blood/ Labs for mononucleosis?
increased lymphocyte and monocyte counts, development and persistence of heterophile antibodies.
Circulating B cells spread the infection throughout reticular endothelial system, which includes the liver, spleen, and peripheral lymph nodes. Infection of B lymphocytes produces a humoral and cellular response to the virus. The T-lymphocyte response is essential in controlling the infection because this response determines the clinical expression of viral infection. A rapid and efficient T-cell response results in control of the infection and lifelong suppression of EBV, whereas an ineffective T-cell response may lead to excessive and uncontrolled B-cell proliferation, resulting in B-lymphocyte malignancies.
Nursing interventions for mononucleosis
During the acute illness, stress the need for bed rest. Warn the patient to avoid excessive activity, which could lead to splenic rupture. If the patient is a student, explain that undertaking less demanding school assignments and seeing friends are fine, but he or she should avoid long, difficult projects until after recovery.
Patients should avoid exposing other people to their affected body secretions because virus remains viable for months after the initial infection
Staphylococcal scalded skin syndrome (SSSS)
Causes:
Contact Precautions
severe skin disorder
epidermal erythema, peeling, and necrosis that give the skin a scalded appearance.
Most prevalent in infants ages 1 to 3 months but may develop in children younger than age 5 years. Rarely, this disorder may affect adults undergoing immunosuppressant therapy.
most children recover fully; however, the mortality rate for adults with SSSS secondary to toxigenic Staphylococcus aureus in the blood is more than 60%.
Transmission usually from asymptomatic carrier. Predisposing factors may include impaired immunity and renal insufficiency, which are present to some extent in the normal neonate because of immature development of these systems.
Symptoms of Staphylococcal scalded skin syndrome
3 stages
- Erythema: Erythema becomes visible usually around the mouth and other orifices; may spread in widening circles over the entire body surface.
- Exfoliation (24 to 48 hours later): With the more common, localized form of the disease, superficial erosions and minimal crusting occur, usually around body orifices, and may spread to exposed skin areas. With the more severe form of SSSS, large, flaccid bullae erupt and may spread to cover extensive body areas. When they rupture, these bullae expose sections of tender, oozing, denuded skin. Intact lesions may not be found because the bullae are fragile; only the erosions may be visible. At first, the patient with this disorder may appear to be sunburned or to have scarlet fever, but inspection of the mouth shows the lack the oral lesions characteristic of scarlet fever.
- Desquamation: In this final stage, affected areas dry up & powdery scales form. Sheets of epidermis shed, and the skin appears reddish in 5 to 7 days. Residual scarring is rare.
During initial disease stages, palpation of affected areas results in Nikolsky sign (sloughing of the skin when friction is applied). Bullae are so fragile that minimal palpation produces tender, red, moist areas.
Treatment of Staphylococcal scalded skin syndrome
systemic antibiotic to treat originating infection.
Cloxacillin (a penicillinase-resistant antistaphylococcal antibiotic) is the drug of choice and is used to prevent secondary infection.
In severe cases, fluid and electrolyte replacement measures are also instituted to maintain balance.
Nursing considerations for Staphylococcal scalded skin syndrome
Maintain skin integrity. Use strict aseptic technique to preclude secondary infection, especially during the exfoliation stage (because of open lesions). To prevent friction and sloughing of the skin, leave affected areas uncovered or loosely covered. Place cotton between severely affected fingers and toes to prevent webbing.
Administer warm baths & soaks during the recovery period. Gently debride exfoliated areas.
Isolation
What order does a nurse remove PPE
Always remove gloves first.
Face shield or goggles- touch only straps or strings.
Gown- untie waist, then neck, then pull gown forward toward wrists,turning it inside out.
What kind of mask is used for airborne precautions?
N-95 respirator
Should gloves or cuffs be on the outside
Glove should cover the cuffs of the gown sleeves
Chlamydia is a common cause of which two problems?
Pelvic inflammatory disease
Infertility
Common symptoms of viral hepatitis
ARTHRALGIA
Other symptoms: lethargy, flulike sx, anorexia, N/V, abdominal pain, gi problems, fever.
Normal urine output
30ml/ hour
