COVID-19: Epidemiology and pathophysiology: Difference between revisions

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==Transmission==
==Transmission==
 
[[File:Ro example.png|thumb|Ro Example]]
* [[COVID-19]]: R0 = 2.2 - 4.2
** Where R0 = expected number of secondary cases produced by a single typical infection in a susceptible population (basic reproductive rate)
** R0 for seasonal flu ~ 1.3
** R0 for pandemic flu ~ 1.5-1.8
* Incubation: 5 days (median); range of 2-14 days
* Serial interval duration = 7.5 days
** Serial interval refers to the time from illness onset in successive cases in a transmission chain


==Incubation Period==
==Incubation Period==

Revision as of 10:34, 11 April 2020

Virology

  • Coronaviruses are common human pathogens
    • Cause the common cold
    • In epidemics, cause up to one-third of community-acquired upper respiratory tract infections in adults; and may cause diarrhea in infants and children
  • SARS-CoV-2 is a novel coronavirus (a new strain not previously identified in humans)
    • Likely primary source = bats
    • It is a betacoronavirus in the same subgenus as the severe acute respiratory syndrome (SARS) virus. Middle East respiratory syndrome (MERS) virus is another, more distantly related, betacoronavirus. Like the SARS coronavirus, SARS-CoV-2 uses angiotensin-converting enzyme 2 [ACE2] for cell entry
  • Surface survival time of SARS-CoV-2:
    • stainless steel: persists for 3 hours (or longer)
    • underscores the importance of environmental cleaning / disinfection
      • cleaning gets rid of the proteins that would interfere with a disinfectants effectiveness
    • Note: studied in a simulated lab environment. Lab virions not covered in protein and mucus and other things that would mimic real life and that could prolong survival

Origins

Geographic Distribution

Pathophysiology


Risk Factors

  • Older age
  • Underlying conditions (lung disease, Renal Failure, Malignancy, heart disease, diabetes)


NOT Risk Factors

Transmission

Ro Example
  • COVID-19: R0 = 2.2 - 4.2
    • Where R0 = expected number of secondary cases produced by a single typical infection in a susceptible population (basic reproductive rate)
    • R0 for seasonal flu ~ 1.3
    • R0 for pandemic flu ~ 1.5-1.8
  • Incubation: 5 days (median); range of 2-14 days
  • Serial interval duration = 7.5 days
    • Serial interval refers to the time from illness onset in successive cases in a transmission chain

Incubation Period

Infectious Period

See Also

COVID-19 Pages

References

  1. Xu Z, Shi L, Wang Y et al. Pathological findings of COVID-19 associated with acute respiratory distress syndrome. The Lancet Respiratory Medicine. 2020;8(4):420-422. doi:10.1016/s2213-2600(20)30076-x