Background: Dentists, safeguarding against contagious diseases, face infection risks. The study aimed to assess
post-COVID immunity, quantification of salivary biomarkers for prognostication, and immune surveillance. Materials and methods: A cross-sectional study were done on 91 working Iraqi dentists from June to August 2022. The dual IgG s1 &n, and IgA s1 &n specific to COVID-19 were measured byELISA-specific kits from serum and saliva. From randomly selected 36 out of 91participants CD4 and subtypes TH1 and TH2 were counted by flow cytometry from fresh whole peripheral blood. Results: All CD4, Th1, and Th2 percentage levels were reduced as a whole if compared to known normal value, and Th2 elevated and inhibited the level of Th1 in all study individuals. All cells were significantly associated with a positive history of COVID-19 infection whereas the CD4 was significantly related to the Pfizer type of vaccine, loss of both sense and recovery time within 15 days. A positive correlation was found between CD4 and Th2 and CD4 with IgG n in serum; this antibody was highly significant with positive COVID-19 infection higher than that of serum IgG s1. Noticeably, the IgA (s+n) in serum was associated with a positive history of infection and could be detected in individuals with a duration of the last infection >1-2 years and last vaccine duration > 6- 12 months.

Conclusion: A low percentage level of CD4 and an imbalanceTh1/Th2 ratio made the recovered individual more
susceptible to re-infection but the significantly high percentage of specific COVID antibodies followed one time of infection or booster vaccine dose gave their protection.
Keywords: Post covid-19, CD4, Th1 and Th2,IgG, IgA.