2. Extended learning Outcome
By the end of this course you will be able to:
Discuss COVID-19 mode of disease transmission
Discuss COVID-19 incubation period
Discuss COVID-19 case definition
Discuss COVID-19 prevention
3. Background
• The world is responding to an outbreak of respiratory disease
caused by a novel (new) coronavirus that was first detected in
China
• Currently been detected in 90 locations internationally,
including in the United States.
The virus has been named “SARS-CoV-2” a NEW VIRUS NEVER
SEEN BEFORE IN HUMAN and the disease it causes has been
named “coronavirus disease 2019” (abbreviated “COVID-19”).
4. Important Terminology
Imported cases
Only indicates locations where all cases have been acquired outside the
location of reporting.
Local transmission
Indicates locations where the source of infection is within the
reporting location.
Community transmission
Is evidenced by, the inability to relate confirmed cases through chains
of transmission for a large number of cases, or by increasing positive
tests through routine screening of sentinel samples.
5. Important Terminology
Under investigation
Indicates locations where type of transmission has not been
determined for any cases.
Interrupted transmission
Indicates locations where interruption of transmission has been
demonstrated
6. Mode of Transmission
• The virus is thought to spread mainly from person-to-
person.
Between people who are in close contact with one another
(within about 6 feet).
• Through respiratory droplets produced when an infected
person coughs or sneezes.
These droplets can land in the mouths or noses or eyes of
people who are nearby or possibly be inhaled into the
lungs.
7. Incubation Period
Based on data from the first cases in Wuhan and
investigations conducted by the China CDC and local CDCs,
the incubation time could be generally within 3 to 7 days
(median 5.1 days, similar to SARS and up to 2 weeks as the
longest time from infection to symptoms was 12.5 days.
10. Clinical Presentation
• Risk factors for severe illness are not yet clear, although older
patients and those with chronic medical conditions may be at
higher risk for severe illness.
• Most reported cases have occurred in adults (median age 59
years).
• Approximately one-third to one-half of reported patients had
underlying medical comorbidities, including diabetes,
hypertension & cardiovascular disease
11. Suspected Case
1. A patient with acute respiratory illness (fever and at least one
sign/symptom of respiratory disease (e.g., cough, shortness of
breath),
AND with NO other etiology that fully explains the clinical
presentation
AND a history of travel to or residence in a country/area or
territory reporting local transmission (See situation report) of
COVID-19 disease during the 14 days prior to symptom onset.
12. Suspected Case
2. A patient with any acute respiratory illness
AND having been in contact with a confirmed or probable
COVID-19 case in the last 14 days prior to onset of symptoms
13. Suspected Case
3. A patient with severe acute respiratory infection (fever and at
least one sign/symptom of respiratory disease (e.g., cough,
shortness breath)
AND requiring hospitalization
AND with no other etiology that fully explains the clinical
presentation.
14. Confirm Case
A person with laboratory confirmation of COVID-19 infection,
irrespective of clinical signs and symptoms.
15. Collection of Specimens for Laboratory Diagnosis
Collect specimens from both the upper respiratory tract (
nasopharyngeal and oropharyngeal) and lower respiratory
tract(Expectorated sputum, endotracheal aspirate, Broncho alveolar
lavage) for nCOV testing by RT-PCR or Gene-Expert. Clinicians may
elect to collect only LRT samples when these are readily available (for
example in mechanically ventilated patients).
Approved Antigen Rapid Diagnostic Test (RDT) would be the first
diagnostic test for suspected COVID-19 patients in health care
facilities. Only suspected patients with negative RDT will proceed to
have RT-PCR testing if required