Infectious Disease Flashcards
Emerging Infectious DIseases
outbreaks of previously unknown diseases or known diseases whose incidence in humans have increased or threatens to increase in the future
Re-emerging Infectious Diseases
diseases that have reappeared after a significant decline in incidence
ex) measles, mumps
What percentages of death worldwide each year are associated with ID?
25%
Since the 1970’s how many ID have been discovered and primarily what kind?
40 infectious diseases that are mostly viruses
Factors that contribute to emergence/re-emergence of ID
Human demographics and behavior (HIV)
Human suscpetibility to infection (transplants)
Technology and Industry
Economic development and land use
International travel
Microbial adaptation (resistance and mutations)
Climate/Weather
Changing ecosystems
Breakdown of public health measures
Poverty
Wildlife trade
War and Famine
Lack of political will
Intent to harm
Pathogens in animals spread to humans
Anti-vaccination
COVID-19
What is it? viral respiratory infection caused by coronavirus (SARS-CoV-2)
- single strand enveloped RNA virus
When do symptoms appear for COVID-19
within 2-14 days after exposure –> can be contagious in this time
Common Symptoms of COVID-19
fever, cough, SOB, fatigue, muscle aches, headache, loss of taste/smell,, sore throat, congestion, N/V/D
Risk Groups for COVID-19
older age (greater than 65 yo)
comorbidities
- OBESITY
- cancer
- CKD
- COPD
- immunocompromised
- CVD
- sickle cell
- T2DM
Demographics of COVID-19 Hospitalizations
- adults 20-44 accounted for 20% of hospitalizations
- blacks, native americans, hispanics were hospitalized at greater rates
Transmission of COVID-19
- spread by respiratory droplets
Incubation period for COVID-19
mean incubation was 5-6 days (range from 2-12 days)
Viral Shedding
ability to culture live virus
- mild to moderate infection: remains infectious no longer than 10 days after symptoms onset
- severe: remains infectious no longer than 20 days after symptoms onset
VIRAL RNA MAY BE DETECTED FOR LONGER PERIODS OF TIME DUE TO DEAD VIRUS –> PROBLEM WITH PCR TESTING
Stages of COVID-19 Disease Progression
Stage 1: Early Infection
- viral replication occurs
- Symptoms: mild, fever, cough
- Signs: lymphopenia
- Treat: antiviral
Stage 2: Pulmonary Phase
- Symptoms: SOB with/without hypoxia
- Signs: abnormal chest xray, transaminitis, low procalcitonin
Stage 3: Hyperinflammation Phase
- Symptoms: ARDS, SIRS/Shock, Cardiac Failure
- Signs: elevated inflammatory markers
- Treat: antiinflammtory
Evidence for Trials in COVID-19 Era
trials were desperate with:
- small sample size
- poor study design
- lack of control group
- rush to publication
- not peer reviewed and pre prints available
- personal experiences
Treatment of COVID-19 Guidelines
Critically Ill Patients (mechanical ventilation, organ dysfunction, sepsis) –> Dexamethasone 6 mg IV/PO for 10 days
Severe but not critically ill (SpO2 < 94% on room air) –> suggests Dexamethasone 6 mg IV/PO
Mild to Moderate (SpO2 > 94% not requiring supplemental oxygen) –> no glucocorticoids
Hospitalized adults with progressive severe or critical COVID-19 who have elevated inflammatory markers –> tocilizumab + Dexamethasone
- if tocilizumab is not available, suggests sarilumab
NO INHALED GLUCOCORTICOIDS
Clinical Trial: RECOVERY Trial
Equivalent Dosing to Dexamethasone 6 mg?
Methylprednisolone 32 mg
Prednisone 40 mg
Tocilizumab
FDA approved monoclonal antibody against the IL-6 receptor
- binds to both membrane bound and soluble IL-6R
benefits in patients with CRP > 7.5 mg/dL
Remdesivir (Veklury)
MOA: interferes with viral RNA dependent RNA polymerase –> inhibits viral replication
Initially developed for Ebola virus: failed
PK:
- IV only
- highly protein bound (no BBB access)
- CYP3A4 substrate
- t1/2: 0.84 - 1.04 hours
Side Effects:
- AST/ALT increase
- phlebitis
- constipation
- dyspepsia
- headache
- nausea
- extremity pain
What solubilizes Remedesivir in IV?
Sulfobutylether-beta cyclodextrin (SBECD)
Remdesivir 150 mg solution –> 9 grams
Remdesivir 150 mg powder –> 4.5 grams
Voriconazole 400 mg –> 6.4 grams
Remdesivir Place in Treatment for COVID-19
(Ambulatory or hospitalized) Mild to moderate at high risk for progression to severe disease –> suggests initiation within 7 days of symptoms onset
- Dosing: 200 mg on Day 1, 100 mg on Days 2 and 3
Patients on supplemental oxygen but no mechanical ventilation –> suggests treatment with 5 days compared to 10 days
Hospitalized patients with severe COVID-19 –> suggests use
NO USE WITH MECHANICAL VENTILATION
Clinical Trial: ACTT-1
Paxlovid Place in Treatment for COVID-19
Paxlovid: nirmatrelvir + Ritonavir
MOA: inhibits hepatic metabolism
Ambulatory patients with mild to moderate COVID-19 at high risk of progression to severe disease –> suggests initiation within 5 days of symptoms onset
- must screen for drug drug interactions due to Ritonavir (CYP3A4 and P-gP inhibitor)
Dosing:
- GFR > 60 mL/min: 300/100 mg every 12 hours for 5 days
- GFR < 60 mL/min: 150/100 mg every 12 hours for 5 days
- GFR < 30 mL/min: DO NOT USE
Monkeypox
- disease caused by monkeypox virus in Africa
- part of the same family as smallpox but is rarely fatal
- outbreak in Marion county in 2022-2023
Signs/Symptoms of Monkeypox
RASH
fever
chills
enlarged lymph nodes
pruritus
headache
malaise
myalgia