Emerging and reemerging infectious diseases Flashcards
What are emerging infecitous diseases?
outbreaks of previously unknown diseases or
known diseases whose incidence in humans has
significantly increased in the past two decades.
What are reemerging infecitous diseases?
known diseases that have reappeared after a significant
decline in incidence
What plays a role in emergence or reemergence of infectious diseases?
Human demographics and behavior
technology and industry
economic development and land use
international travel and commerce
microbial adaptation and change
breakdown of public health measures
climate change
Worldwide more than _________ people are affected each
year by measles with ________ deaths globally.
20 million and 164000 deaths
What is lyme disease?
emerging bacterial disease transmitted by deer ticks
What is XDR-TB
extensively drugresistant tuberculosis
________ people in the world is infected with dormant TB bacteria
One in three
What happens if first-line TB drugs are misused?
multi-drug-resistant TB (MDR-TB) can develop = need for second-line TB drugs (more expensvie and risky)
What is SARS
Severe acute respiratory illness caused by a coronavirus (SARS-CoV) first reported in Asia in Feb2003
Every year ___________ children worldwide die from
vaccine-preventable diseases before they reach
age 5.
1.4 million
What is the cause of measles
caused by measles virus (paramyxovirus of genus Morbillivirus) rubeola virus which is caused by respiratory droplets or airborne transmissions (contagious for 4 days before onset of rash until abt 4 days after onset) (incubation period is 8 to 12 days)
no cure, runs it’s course in 7-10 days
What is mump?
caused paramyxovirus which is spread through contact with respiratory secretions, saliva, or fomites (incubation is 14-21 days, contagius for 1-7 days and up 9 after swelling)
- causing inflammation and swelling of 1 or both parotid glands
What is the MMR vaccine
measles, mumps, rubella
What is rubella
aka german measles or 3 day measles, caused by rubella virus, spread through respiratory droplets, airborne transmission and from pregnant women to fetuses
(incubation after exposure is 14-31, pt is contagious from 1 wk before eruption ofrash until 1 week after onset)
(spraodic epidemics r often on college campuses)
what happens if a prego women get rubella?
may cause congenital rubella syndrome
What is whooping cough?
caused by bordetella pertussis (which releases toxin that leads to necrosis of mucosa), spread by contact with respiratory droplets
- 3 stages: highly contagius catarrhal stage when child seems to ahve common cold, paroxysmal stage when cough becomes violent, ending in high-pitched inspiratory whoop, often follwoed by vomiting of thick mucus, convalescent stage when cough gradually diminishes
What is the DTP vaccine
diphtheria, tetanus, pertussis vaccine
What is diphtheria?
caused by Corynebacterium Diptheria, primarily spread by respiratory droplets; transmission by fomites is rare
- necrosis of mucous membrane in respiraotry
produces a toxin that coats the nose, throat or airway that may hinder breathing and swallow
in bloodstream toxin can cause damge to heart, kidne and nervous ststem
up t o50% of pt w/o treatment die
- diagnosis is based on throat culture for C. diphetheriae and antibodies in serum
treatment - antibiotics and diphtheria antitoxins
What is tetanus?
caused by Clostridium tetani, bacteria is found in contaminated soil and animal excrement and enter the body via wound
(incubation is 3-21 days, onset commonly occuring at abt 8 days)
produces toxin that affects the nervous system
what is the chickenpox?
caused by the varicella-zoster (human perpes virus 3 (HHV-3) virus, spread through direct cotnact, droplet transmission and airborne transmission
- systemic disease w/ superficial cutaneous lesions that begin as red macules that progress to papules and finally become vesicles
- first on face or trunk and then spread to face or trunk
- pt experiecne fever, malaise and anorexia
- lesions continue to erupt for 3-4 days and cause intense itching
- recovery in 2 wks, leaving the person with lifetime immunity
- complication include secondary bacterial infection, viral pneumonia, conjunctival ulcers and Reye syndrome
How many chickenpox cases globally?
60 mill
How long is a person with chicken pox contagious?
48 hours before the initial rash occurs until all blisters have burst and crusted over
What is Haemophilus influenzae type b (Hib)
a bacterium that causes diseases including meningitis and pneumonia (lives in human respiratory tract- found in 90% of healthy ppl)
How many Hib cases and death yrly
8 million cases occur, causing 371,000 deaths
among young children
What is poliomyelitis?
caused by polio virus, transmitted by person to person contact or by contact with infectious saliva or feces
what r the 2 types of polio?
nonparalytic polio and paralytic polio.
Polio is asymptomatic in approximately __% of cases
95
What is another type of nonparalytic polio?
nonparalytic aspectic meningitis
What is Steptococcus pneumoniae?
causes meningitis and upper + lower respiratory disease (kills approx 1 mill children yrlr globallym found in 1/2 population) and is transmitted by respiratory droplets
What is MRSA?
Methicillin resistant strains of Staphylo-coccus aureis
- began showing up in hospitals, jails, crowded living quarters and other comunity environments
- aggressive skin and soft tissue infection (can be mistake for spider bites but lesions quickly develop into abscess and cellulitis)
- can cause pneumonia, bone infections and septicemia
- occasionally toxic and resitant straisn of MRSA have been termed flesh eating bacteria
- leading cause of surgical wound infection is hospials bc easily transmitted and survive fr a long time nearly anywhere
What is VRE?
Vancomycin-resistant Enterococcus
- growing problems in chronic care facilites and hospitals bc there r only few antiotics that can be sued to treat VRE
What are CRE?
- carbapenem-resistant Enterobacteriaceane
- difficult to treat bc they have high levels of resistance to even last reosort antibiotics
- more comonly occur among pt who r receiving treatment for other infections
What is acinetobacter baumannii?
- multidrig- resistant bacterium
- capable of causing infection and death
- escpecially in those with compromised immune systems frail elderly, chronically hospitalized
- introduced to NOrth America by troops returining to Canaada from Middle East
How to diagnose and treat chickenpox?
diagnose - history of exposure, presence of cutaneous eruptoins, visualize VZV when culture of vesicular fluid is examined microscopically, after infeciotn, antibodies r found i nserum
treat - palliative treatment, cool bicarbonate of soda baths, cornstarch dusting or application of calamine lotion (helps control scratching that can lead to secondary infection and scarrig), administration of acetaminophen for fever and pain (no aspririn bc risk fo Reye syndrome)
s/s of diphtheria?
- early s/s include low-grade fever and sore throat
- dysphagia
- cough
- hoarseness
- chills
- fever
- swollen regional lymph nodes
- foul breath
- cyanosis
- grayish patches of thick mucous membrane (known as pseudomembrane or false membrane) composed of bacteria, inflammatory cells, dead tissue and fibrin, surrounded by inflammation, swelling that can interfere w/ airway function, impairing swallowing and speech
- otitis media
- pneumonia
- myocarditis
- paralysis
how to diagnose and treat mumps?
diagnose - history of exposure, clinical picture that includes swelling of parotid glands, asses for tederness of testes, serum amylase is often elevated, nwe polynerase chain reaction (PCR) test
treatm - acetaminophen, warm or cold compress r applied for pain, soft or liquid diet to minimize discomfort when eating, scrotal support
diagnose and treat whooping cough?
diagnose - bacteiral studies of nasopharyngeal mucus for pertussis bacillus, PCR test, elevated WBC count
treatment - erythromucin, increase fluid intake, nutritious diet, quiet and rest, observe for respirotory distress and other complication (bronchopneumonia, convulsion, hemorrhages)
diagnose and treat measles?
diagnose - history of exposure and clinical picture, rash and presence of Koplike spot on oral mucosa
treat - acetaminophen is given to treat fever, tepid sponge baths, protect pt eyes from bright light, antibiotics if secondary infections
What is subacute sclerosing panencephalitis?
- rare infectious condiont of CNS, one of 3 forms of encephalitis occuring secondary to measles virus, evolves after reactivation of dormant measles virus
- causes atrophy of cortical areas of brain, demyelination of nerves or ventricular dilation
- s/s merge w/ insidious onset and r identified by progressive motor and mentla orintellectual deterioriration including personality changes and neurologica detrioration sunsequently reslting in severdementia, seiures, blindness and vere
- pt r usually 5-20 w/ measles 2-10 prior
- CSD show elevated gamma globulin levels
- no cure so supportive, inculding drug therapy for seizure control
- duration is several yrs w/ progressive deterioration of CNS (pt is usually nonresponsive and unable to care for themsleves)
What is congenital rubella syndrome?
- transferred to fetus during first trimester of pregnancy, variety of congentical deformities r seen in 25% of births
s/s of measles
cough, coryza, conjunctivitis, photophobia, fever, red, blotchy rash starting behind ear, hairline, forehead and then progressing down body (before eruption of rash, Koplike spots can be detected on oral mucosa as tiny white spots on red background)
s/s of mumps
tenderness in neck in front of and below ear in region of parotid glands pain on swallowing
rash
headache
muscle aches
low-grade fever
loss of appetite
earache that is aggravated by chewing mump orchitis in miles = sterility is complicaiton
s/s of rubella
children has rose- colored, slightly elevated rash that appears first on face and head and then progresses downward, low-gradefever, tenderness and enlargement of lymph nodes, transient arthritis, myocarditis and hemorrhagic manifestiation
diagnose and treat rubella
- diagnose w/ hisotry of exposure, clinical picutre, throat culture for rubella and serologic studies to detect antibodies
- treatment consists of supportive measures, including administration of mild analgesic for fever and joint pain
