EFFECTIVENESS OF SECOND DOSE PFIZER COVID-19; A CASE REPORT FROM WORKPLACE TRANSMISSION

Abstract

Coronavirus disease 2019 (Covid-19) is a zoonotic disease that outbreaks from Wuhan, China, leading to pandemic disease declared by WHO in March 2020¹. They transmitted by asymptomatic or symptomatic individuals via air droplets and airborne². Work-related transmission is one of the known patrons of the outbreaks³. Fortunately, the availability of effective vaccines potentially reduce viral load and suppress the transmission rate. Here we report workplace transmission cases protected against Covid-19 in those who completed the second dose of Pfizer COMIRNATY. Case 1, 33 years old health care worker Malay lady partially  vaccinated, acquired Covid 19 from parents living in the same household (House A). Case 2 is her husband completed two doses of vaccines remains negative for consecutive RT PCR testing. Both were asymptomatic. On further contact tracing among her co-workers, Case 3 to Case 7 were identified among close contact and were tested by RT PCR on the next day. Out of 5 cases, only Case 7 was positive. Cycle threshold (Ct) value for both Case 1 and Case 7 were, 21.6 respectively. Further history noted that the four cases (Case 3-6) have completed the second dose of Pfizer COMIRNATY more than two weeks apart. Close contact tracing for case 7, showed positive to her son but negative to her husband, who has completed two doses of Pfizer COMIRNATY more than two weeks apart. Figure 1 illustrated the cases transmission. In total, only one co-worker was infected with coronavirus. Based on the Israeli cohort study, that a single dose may provide an inadequate protection.⁴ This case illustrates that the importance of completed two doses Pfizer COVID-19 for protecting against Covid-19 infection. However, further wider study is required to offer adequate assessment on the vaccine effectives and infectiousness.