The goal of this observational study is to evaluate the protective effect of immunebarrier on secondary infection after COVID-19 (coronavirus disease 2019) vaccination orCOVID-19 virus Omicron B A. 5.2 strain infection by dynamically monitoring the COVID-19antibody titer, cellular immune function and the occurrence of secondary infection ofhealthy participants, mainly medical staff in our hospital, to understand the crossprotective effect of COVID-19 antibody on different variants of Omicron, and explore thebest time to use COVID-19 vaccine to strengthen immunity after Omicron mutant infection.
This study is a single center, prospective, non-intervention study. It is planned to
recruit 300 medical and nursing participants, administrative and logistics participants
or other participants who can cooperate with the follow-up for 48 weeks to voluntarily
join the group.
Participants will be investigated about the vaccination history of COVID-19 vaccine,
whether they have ever been infected with COVID-19, the time of initial infection with
COVID-19, and following clinical symptoms.The COVID-19 antibody titer of peripheral blood
will be used for baseline.
The participants will be divided into positive group and negative group according to the
COVID-19 antibody titer results,then they wii be followed up for 48 weeks.If the
participants have no symptoms related to COVID-19 infection, COVID-19 antibody and
COVID-19 nucleic acid will be tested every 4-8 weeks according to the epidemic situation
(the specific visit time is initially set as 0 week, 6 ± 2 weeks, 12 ± 4 weeks, 20 ± 4
weeks, 28 ± 4 weeks, 36 ± 4 weeks, 48 ± 4 weeks). There will be about 7 visits in total,
according to the epidemic situation and the time of secondary infection of the
participants). If the nucleic acid turns to be positive, we will consider it as the
asymptomatic infection, then we will collect nasal/pharyngeal swabs for gene sequencing
of virus strains, and terminate the study.
If the participants get fever, fatigue, sore throat, cough, nasal congestion, runny nose,
muscle soreness or headache and other symptoms related to COVID-19 infection during the
study period, they need to test the COVID-19 antigen or COVID-19 nucleic acid within 48
hours. If it is positive, we will collect nasal/pharyngeal swabs for gene sequencing of
virus strains, and terminate the study in advance.
Inclusion Criteria:
1. No age limit, no gender limit;
2. Medical staff, administrative and logistics staff who work in the Third Affiliated
Hospital of Sun Yat-Sen University or other participants who can cooperate with the
follow-up for 48 weeks;
3. The participants need to be sure whether they have ever been infected with COVID-19,
and need to be clearly remember the time when they first infected with COVID-19.
Exclusion Criteria:
1. Have the following serious respiratory diseases: such as asthma, bronchiectasis,
chronic obstructive pulmonary disease, pulmonary interstitial disease, tuberculosis
and other respiratory diseases that may interfere with symptom observation;
2. Those with other serious diseases or disease history that affect immune function,
including but not limited to uncontrolled and unresectable malignant
tumors,hematological diseases, cachexia, active bleeding, severe malnutrition,
mental diseases, autoimmune diseases, HIV, etc.
3. Those who have long-term assignment plans and cannot return to the hospital
regularly for follow-up.
The Third Affiliated Hospital of Sun Yat-sen University
Guangzhou, Guangdong, China
Investigator: Liang Bing Lin, MD
Contact: 13924129928
lamikin@126.com
Not Provided