University of Siena, Banchi di Sotto, 55, 53100 Siena, Italy.
Federal University of São Paulo, Rua Borges Lagoa 770, Vila Clementino, São Paulo - SP, 04038-001 São Paulo, Brazil.
Vaccine. 2023 Sep 7;41(39):5769-5774. doi: 10.1016/j.vaccine.2023.08.008. Epub 2023 Aug 11.
Worldwide, tetanus-diphtheria-acellular pertussis (Tdap) vaccination coverage of healthcare professionals (HCPs) is below 40%, but this data is not available for Brazil. We hypothesize that a high number of HCPs are not immune to pertussis in Brazil. Main objective was to determine the seroprevalence of anti-pertussis toxin (anti-PT IgG) among HCPs. Secondary objectives were to evaluate Tdap vaccination coverage, to assess predictive factors associated with anti-PT IgG, and to estimate the decay of anti-PT IgG and time to Tdap vaccination.
Observational cross-sectional serological study in 352 HCPs who worked at São Paulo Hospital - Federal University of São Paulo (UNIFESP) in 2020, approved by UNIFESP Ethics Committee. Data collected included sociodemographics, knowledge about Tdap, and vaccination status. Anti-PT IgG were quantified by ELISA: <10 IU/mL seronegative and ≥ 10-1000 IU/mL seropositive. Titers ≥ 10-50 IU/mL were classified low positivity, indicating no recent B. pertussis infection or Tdap vaccination; >50 IU/mL high positivity, indicating recent B. pertussis infection or Tdap vaccination, and > 100 IU/mL as acute B. pertussis infection or Tdap vaccination in the previous year. Comparisons were done by Chi-square test, multivariable logistic regression, and Pearsońs correlation, at 5% p-level.
331/352 HCPs were not aware the Brazilian National Immunization Program recommends Tdap for all HCPs and pregnant women. 68/339 HCPs received Tdap (mean 3.1 ± 2.0 years). 55/352 were seronegative for pertussis, all unvaccinated. 56/271 with no history of Tdap vaccination had high positivity. The probability of anti-PT IgG > 50 IU/mL was 11.5 times higher in Tdap vaccinated HCPs than in non-vaccinated (p < 0.001). There was a weak but significant correlation between anti-PT IgG and interval of Tdap vaccination (r = 0.404; p = 0.001). Anti-PT IgG dropped 5 IU/mL/year (p = 0.001).
Better education of HCPs on needs and benefits of Tdap vaccination is critical. Goals must be to improve HCPs vaccination coverage.
在全球范围内，医疗保健专业人员（HCPs）的破伤风-白喉-无细胞百日咳（Tdap）疫苗接种覆盖率低于 40%，但巴西没有相关数据。我们假设巴西有大量的 HCPs 对百日咳没有免疫力。主要目标是确定 HCPs 抗百日咳毒素（anti-PT IgG）的血清阳性率。次要目标是评估 Tdap 疫苗接种覆盖率，评估与抗-PT IgG 相关的预测因素，并估计抗-PT IgG 的衰减和 Tdap 疫苗接种时间。
这是一项在 2020 年于圣保罗联邦大学（UNIFESP）工作的 352 名 HCPs 中进行的观察性横断面血清学研究，得到了 UNIFESP 伦理委员会的批准。收集的数据包括社会人口统计学、对 Tdap 的了解以及疫苗接种状况。抗-PT IgG 通过 ELISA 进行定量：<10 IU/mL 为血清阴性，≥10-1000 IU/mL 为血清阳性。滴度≥10-50 IU/mL 被归类为低阳性，表明没有近期 B. pertussis 感染或 Tdap 疫苗接种；>50 IU/mL 为高阳性，表明近期 B. pertussis 感染或 Tdap 疫苗接种，>100 IU/mL 为急性 B. pertussis 感染或 Tdap 疫苗接种在前一年。采用卡方检验、多变量逻辑回归和 Pearson 相关分析进行比较，p 值均为 5%。
331/352 名 HCPs 不知道巴西国家免疫计划建议所有 HCPs 和孕妇接种 Tdap。339 名 HCPs 中有 68 人（平均 3.1±2.0 年）接受了 Tdap 接种。55/352 名 HCPs 对百日咳呈血清阴性，均未接种疫苗。271 名无 Tdap 疫苗接种史的 HCPs 中有 56 人呈高阳性。与未接种疫苗的 HCPs 相比，接种过 Tdap 的 HCPs 抗-PT IgG>50 IU/mL 的概率高 11.5 倍（p<0.001）。抗-PT IgG 与 Tdap 疫苗接种间隔呈弱但显著相关（r=0.404；p=0.001）。抗-PT IgG 每年下降 5 IU/mL（p=0.001）。
对 HCPs 进行 Tdap 疫苗接种需求和益处的教育至关重要。目标必须是提高 HCPs 的疫苗接种覆盖率。
