Anti-Spike Antibody Responses to Covid-19 Vaccine 3 Doses in Health Care Workers Working in Acute Care Hospital in Myanmar

Background The health care workers are prone to COVID-19 infection as they are working in front line; thus, they are in priority groups for vaccination. This study aimed to assess the level of anti-Spike antibody 2 weeks after 3 doses of COVID-19 vaccine among health care workers (HCW). Methods A cross-sectional descriptive study was conducted in July 2022 among health care workers (HCW) who received COVID-19 vaccine 3 doses. Data were collected by using standardized forms and analysis was done. Results A total of 42 HCW were included; the mean anti-Spike antibody level was 3734.19 U/mL. Female had higher anti-Spike antibody level than male, 4857.67 U/mL and 3427.78 U/mL respectively. HCW with diabetes mellitus had significantly higher anti-Spike antibody level 6740.00 U/mL than those without diabetes mellitus 2884.00 U/mL. Anti-Spike antibody level in smokers (3376.42 U/mL) was lower than that of non-smoker (3845.99 U/mL). HCW with history of COVID-19 infection had higher anti-Spike antibody level (4013.79 U/mL) than that of those without infection (3524.48 U/mL); those with history of COVID-19 infection in fourth wave (The Omicron outbreak; 6 months ago) had higher antibody level (4013.79 U/mL) than that of those with history of infection in third wave only (The Delta outbreak; one year ago) (3524.48 U/mL). HCW who got vaccinated in the afternoon had higher antibody level (4350.77 U/mL) than who got in the morning (2912.07 U/mL). Negative relation was detected between time from last vaccination to anti-Spike protein antibody level though it was not statistically significant. Significant predictors for anti-Spike antibody level on univariable analysis were BMI and presence of diabetes. Conclusions Anti-Spike antibody level was significantly related with BMI and diabetes mellitus; those with high BMI and diabetes mellitus had higher level of antibody. Anti-Spike antibody level was relatively higher in female; non-smokers; those with COVID-19 infection particularly in fourth wave (The Omicron infection); those with shorter duration from last vaccination; and those who got vaccination in the afternoon although it was not significant statistically.