ABSTRACT
OBJECTIVE@#To investigate whether Omicron BA.1 breakthrough infection after receiving the SARS-CoV-2 vaccine could create a strong immunity barrier.@*METHODS@#Blood samples were collected at two different time points from 124 Omicron BA.1 breakthrough infected patients and 124 controls matched for age, gender, and vaccination profile. Live virus-neutralizing antibodies against five SARS-CoV-2 variants, including WT, Gamma, Beta, Delta, and Omicron BA.1, and T-lymphocyte lymphocyte counts in both groups were measured and statistically analyzed.@*RESULTS@#The neutralizing antibody titers against five different variants of SARS-CoV-2 were significantly increased in the vaccinated population infected with the Omicron BA.1 variant at 3 months after infection, but mainly increased the antibody level against the WT strain, and the antibody against the Omicron strain was the lowest. The neutralizing antibody level decreased rapidly 6 months after infection. The T-lymphocyte cell counts of patients with mild and moderate disease recovered at 3 months and completely returned to the normal state at 6 months.@*CONCLUSION@#Omicron BA.1 breakthrough infection mainly evoked humoral immune memory in the original strain after vaccination and hardly produced neutralizing antibodies specific to Omicron BA.1. Neutralizing antibodies against the different strains declined rapidly and showed features similar to those of influenza. Thus, T-lymphocytes may play an important role in recovery.
Subject(s)
Humans , Antibodies, Neutralizing , Prospective Studies , SARS-CoV-2 , Breakthrough Infections , COVID-19 Vaccines , COVID-19 , T-Lymphocytes , China/epidemiology , Antibodies, ViralABSTRACT
The pertussis surveillance system has been established since 2009 in Tianjin, and continuously improved over the past 10 years. This system determines the definition and classification of pertussis, establishes simple and feasible sampling methods and laboratory detection methods in clinical practice, standardizes the report management of pertussis cases and the treatment of epidemic situations. After the implementation of the surveillance system, the number of reported pertussis cases increased from 26 in 2009 to 802 in 2017, the number of diagnosed cases increased from 19 in 2009 to 662 in 2017, the reported incidence rate of pertussis increased from 0.16/100 000 in 2009 to 4.28/100 000 in 2017, and the number of medical institutions of reporting perutssis cases increased from 2 in 2009 to 53 in 2017. The specimen collection rate of the reported cases reached up to 93.66%. These results show that the sensitivity of pertussis surveillance has been improved and show that the data from the surveillance system may reflect more precisely the epidemical characteristics of perutssis in Tianjin.
Subject(s)
Humans , Infant , Incidence , Pertussis Vaccine , Whooping CoughABSTRACT
<p><b>OBJECTIVE</b>To evaluate the effects of prevention and control strategies on hepatitis A.</p><p><b>METHODS</b>Surveillance data on hepatitis A from 1990 to 2006 in Tianjin was analyzed, and the coverage rate of hepatitis A vaccine among targeted population was estimated, to compare the anti-HAV IgG level of children younger than 15 years old in 1999 and in 2005.</p><p><b>RESULTS</b>Results showed that a) the morbidity of hepatitis A decreased from 25.26/10(5) in 1990 to 0.82/10(5) in 2006; b) the ratio of hepatitis A in viral hepatitis decreased from 30.43% in 1990 to 1.05% in 2006; c) the estimated coverage rate was 72.7%; d) the positive rate of anti-HAV among children younger than 15 years old in 2005 was distinctly higher than that in 1999.</p><p><b>CONCLUSION</b>Positive results showed that it was successful to use hepatitis A vaccine as the strategy to prevent and control hepatitis A in the past five years in Tianjin.</p>