COVID-19 can symptomatically and asymptomatically affect patients. Asymptomatic cases have become a particular concern for public health in the COVID-19 pandemic. One of the simple tests for COVID-19 is the complete blood count that can predict systemic inflammation and disease severity. The description of laboratory tests in asymptomatic COVID-19 patients is rarely reported. This study aimed to compare the laboratory test results of both symptomatic and asymptomatic COVID-19 employees of the Muhammadiyah University General Hospital of Malang. Data were taken from medical records. Diagnoses of COVID-19 were confirmed by nasopharynx-oropharynx PCR swab. Patient characteristics included age, gender, and values of hemoglobin, leukocytes, neutrophils, lymphocytes, platelets, NLR and CRP from two different groups: symptomatic and asymptomatic infected employees. There were 104 COVID-19 infected employees at the hospital from April 2020 to February 2021. Female infected employees (52.9%) were more numerous male infected employees. Employees aged 21-30 years accounted for 53.84% of the total cases. The numbers of symptomatic and asymptomatic employees were 10 employees (9.6%) and 94 employees (90.4%), respectively. There was a significant difference between the symptomatic and asymptomatic groups in the numbers of lymphocytes (p = 0.03) and CRP (p = 0.046). There were no significant differences in the other laboratory results. Lymphopenia and increased CRP numbers more often occurred in the symptomatic group compared to the asymptomatic group. Therefore, these parameters can be an indicator for predicting disease severity. However, further research is needed with a bigger sample. Keywords: COVID-19, symptomatic, asymptomatic, Muhammadiyah University General Hospital of Malang

Almost two years since becoming a global threat, the whole world is still looking for the best way to reduce the rate of transmission of COVID-19. One of the ways to deal with COVID-19 is to increase immunity by stimulating antibodies in the community. Antibody-mediated humoral responses are critical to prevent viral infections. Antibodies can also be formed through natural processes when someone is infected by SARS-Cov2 or through vaccination programs. In this study, collective blood samples were taken to examine IgG spike receptor binding domains (IgG S-RBD) between two groups: COVID-19 survivors (n = 50) and health workers who were vaccinated twice with the Sinovac vaccine (n = 50). There were no significant differences in antibody levels between the previous COVID-19 infection group and the health workers groups (p = 0.8). 50% (n = 6) of the health workers who were aged 30-39 had excellent titer antibody levels, as did 50% (n=7) of the COVID-19 survivors group who were in their 30s. Further research is needed to decide the perfect time for booster shots. Keywords: COVID-19, titer antibody, IgG S-RBD, Sinovac