How we define “recovered” and what we know about the virus go hand in hand.
The outbreak of Covid-19 posed several questions in the context of infection and recovery, which remained open due to the lack of knowledge and familiarity with the virus. The treatment of recovered Covid-19 patients varies between different countries, and also between the first and second wave, depending on the accumulated knowledge about the virus.
During the first wave of Covid-19 — when familiarity with the virus was brief — patients were deemed recovered and released from isolation or hospitalization after receiving negative results to PCR tests. After the first wave, many countries changed the criteria for “recovery” from negative test results to set time periods of isolation ordered as of symptom onset.
Many countries are now considering issuing “immunization / recovery certificates” to return recovered Covid-19 patients to routine.
First wave of Covid-19 (January 2020 – April 2020)
On January 12, due to the spread of the virus, the World Health Organization recommended to confirm a case negative if a patient receives two negative PCR test results within 24 hours and has no symptoms. This recommendation, based on experience with previous viruses, has been adopted in most countries.
Asia
- Taiwan: Three negative PCR tests were required.
- India: Two negative PCR tests were required in 24 hours.
- Singapore: Two negative PCR tests were required 24 hours apart, and a follow-up test two weeks later.
In other asian countries, improvement in clinical symptoms was required:
- Hong Kong: Recovery status was defined as clinical stability for 48 hours, and two negative PCR tests 24 hours apart. One week after discharge, recovered patients were required to perform a respiratory function test.
- China: Two negative PCR tests, normal body temperature for three days, and no respiratory problems were required for a patient to be deemed recovered.
- South Korea: Two negative PCR tests 24 hours apart, and the improvement of clinical symptoms were required for a patient to be deemed recovered.
USA
At least one week after the onset of symptoms: Two negative PCR tests were required 24 hours apart, as well as normal body temperature for three days and improvement in breathing symptoms. In practice, the process was not fully performed due to lack of tests.
Europe
- Sweden: Patients were deemed recovered following a negative PCR test and no symptoms for 14 days, without medical treatment.
- Spain: Patients are deemed recovered after two negative PCR tests 24 hours apart.
In other countries, improvement in clinical symptoms was more meaningful than PCR test results:
- Germany: Patients were deemed recovered 14 days from the onset of symptoms, provided no shortness of breath or pneumonia developed. There is no reference to PCR tests to define recovery.
- Denmark: Patients were deemed recovered 48 hours after the symptoms disappear, no PCR test is needed.
- Austria: Patients were required to perform two negative PCR tests, and be without symptoms for 48 hours. Patients in home isolation were required to be asymptomatic for 48 hours, and consult a doctor.
After the first wave period (May 2020 – Today)
In May 2020, the World Health Organization updated its recommendations for defining Covid-19 recovered patients. The criteria now depend on symptoms, without requiring negative PCR tests.
- Symptomatic patients are deemed recovered if, 10 days after the onset of symptoms, they experience 3 days without symptoms.
- Asymptomatic patients are deemed recovered 10 days after a positive test result.
While may countries continue to use the PCR test method to rule out carriers of the virus, many have changed the criteria for recovery from the “test method” to the “symptom method”.
Israel: A verified patient will be considered recovered if 10 days have passed since the day the positive test was performed, provided that the last three days were asymptomatic. This definition implies that a symptomatic or asymptomatic patient will be defined as “recovered” no earlier than 10 days after being diagnosed. Those who are in high risk groups will be defined as recovered after 20 days from the date of the positive test, provided that the last three days have been asymptomatic.
In Asia, some countries the criteria have not changed.
China: Two negative tests are required 24 hours apart, followed by isolation in rehabilitation centers to perform further tests until discharge and return to routine.
Russia: Two negative tests are required within 24 hours.
India: The criteria have changed — 10 days after the onset of symptoms, tests are still performed for specific cases.
South Africa: The symptom method has been adopted, and release from isolation/hospitalization is possible 14 days after clinical stability (if no resuscitation was required), or 14 days after the onset of symptoms.
UK: All patients are required to perform a negative PCR test in addition to the absence of symptoms.
USA: The World Health Organization’s recommendation has been adopted, and the definition of “recovery” is determined by the absence of symptoms.
Attitudes towards recovered patients around the world
During the first wave period, no different attitudes took place, and no changes were made to the rights of the recovered patients.
In Hong Kong, Taiwan, Japan and South Korea — There are no restrictions or special rights after recovering from Covid-19, and all citizens are required to follow the guidelines.
In China — After recovery, the patient is required to stay in home isolation for an additional 14 days, monitor symptoms and get comprehensive tests at the hospital. Tracking is done by an app.
In Austria, Sweden, the UK and Spain — There are no restrictions of rights for recovered patients, all citizens are required to follow the guidelines.
In the USA — Recovered patients are required to stay in home isolation for seven days after the negative tests.
In October 2020 — following studies and cases around the world — patients exposed to the virus had to isolate again, in case of a second exposure to the virus.
Immune certificates
Germany, Italy, Chile, the United Kingdom, the United States, Madrid and Estonia consider issuing certificates to recovered patients, which would allow them to return to routine without restrictions.
The World Health Organization has opposed issuing virus “immunity” certificates for recovering people. The certificates are issued based on a serological test for antibodies, confirming that the recovered patients are immune or at low risk of re-infection with Covid-19.
The reasons for opposing this process are:
- Uncertainty in the context of long-term immunity
- Unknown reliability of the serological test determining immunity, possible errors, ethical reasons (privacy, stigma, possible forgeries)
- Violation of liberties and individual rights
References:
- Characteristics of recovered COVID-19 patients with recurrent positive RT-PCR findings in Wuhan, China: a retrospective study, Tie-Jun Shui, Chao Li, Hong-bing Liu, Xiaohua Chen and Bi-ke Zhang. 13.10.2020
- Criteria for releasing COVID-19 patients from Isolation, World Health Organization, 17.06.2020.
- Discontinuation of Transmission-Based Precautions and Disposition of Patients with COVID-19 in Healthcare Settings (Interim Guidance), CDC, 10.08.2020.
- Duration of Isolation and Precautions for Adults with COVID-19, CDC, 19.10.2020.
- Immunity certification for COVID-19: ethical considerations, World Health Organization, 01.12.2020.
- The need for improved discharge criteria for hospitalized patients with COVID-19—implications for patients in long-term care facilities, Shirley Sze, Daniel Pan, Caroline M L Williams, Joseph Barker, Jatinder S Minhas, Chris J Miller, Julian W Tang, Iain B Squire, Manish Pareek. 19.09.2020.
- Definition of a new recovery – in accordance with the Public Health Ordinance – Guidelines of the Chief Physician, Ministry of Labor and Welfare, 01.10.2020.
- World policy regarding recovering people from Corona, Corona Information and National Information Center for the Campaign, 22.04.2020.