Childhood immunization during the COVID-19 pandemic in Texas

In 2020, the state of Texas implemented coronavirus disease 2019 (COVID-19) social distancing guidelines in order to prevent surges at Texas hospital emergency rooms and in intensive care units. As noted in other states, an unintended consequence of these activities was significant declines in childhood immunizations. After analyzing state-wide immunization register data for Texas, we observed a 47% relative decline in immunization rates between 2019 and 2020 among 5-month-olds and a 58% decline among 16-month-olds. We observed a small decline (5%) among 24-month-olds, and no decline in vaccines received at birth (Hepatitis B). Declines were larger in rural counties compared to urban. These declines are superimposed on increases in state vaccine exemptions over the last five years due to an aggressive anti-vaccine movement in Texas. There are concerns that continued declines in childhood immunization coverage due to COVID-19 could lead to co-endemics of measles and other vaccine preventable diseases.     

Immunogenicity and reactogenicity of BNT162b2 booster in BBIBP-CorV-vaccinated individuals compared with homologous BNT162b2 vaccination: Results of a pilot prospective cohort study from Lebanon

Facing new COVID-19 waves, the effectiveness of BBIBP-CorV has been noted to be low in countries whose populations were already administered two doses of the vaccine. Heterologous vaccination using ChAdOx1-S/BNT162b2 elicited higher immunogenicity compared with homologous immunization. BBIBP-CorV/BNT162b2 combination is worth testing. In this pilot prospective cohort study conducted at Makassed General Hospital, Beirut, Lebanon, from February 17, 2021, to June 30, 2021, we tested the safety and immunogenicity of a BNT162b2 booster dose in COVID-19-naïve individuals who had received two doses of the BBIBP-CorV vaccine. Heterologous booster vaccination was found to be safe and well tolerated. It was significantly associated with higher anti-spike IgG geometric mean titers compared to that after homologous BNT162b2 immunization in COVID-19-naïve individuals [(8040 BAU/mL, 95% confidence interval (CI), 4612–14 016) vs (1384 BAU/mL, 95% CI, 1063–1801), respectively, (P < 0.0001)]. In countries with limited access to mRNA vaccines and where populations have already received BBIBP-CorV, mixing BBIBP-CorV/BNT162b2 is seen to overcome the low immunogenicity induced by BBIBP-CorV alone, thus potentially providing protection against emerging variants.     

2016—2019年北京市石景山区学校及托幼机构水痘流行病学特征分析

目的 对2016—2019年北京市石景山区学校及托幼机构水痘病例流行病学特征进行分析,了解水痘的发病规律,为水痘疫情防控工作提供依据。方法 对2016—2019年北京市石景山区学校及托幼机构的水痘病例进行描述性流行病学分析。结果 2016—2019年北京市石景山区学校及托幼机构的水痘病例集中在每年的4—6月份和10—12月份,小学生是水痘病例的高发人群占35.49%。24.62%的病例有明确的接触史,59.70%的病例既往接种过水痘疫苗。有免疫史和无免疫史病例的发热情况差异有统计学意义(χ2=24.754,P＜0.001)、出疹程度的分布差异有统计学意义(χ2=74.309,P＜0.001)。结论 2016—2019年北京市石景山区学校及托幼机构水痘病例的时间分布呈现“双峰分布”;疫情防控的重点人群为小学生,同时应加强大学校园的疫情防控;水痘疫情防控工作中,应当重视带状疱疹病人和有水痘疫苗免疫史的轻症病例。     

Public health facility quality and child immunization outcomes in rural India: A decomposition analysis

Universal coverage of routine childhood vaccines remains a challenge in many low- and middle-income countries (LMICs). In India, vaccination campaigns have increased full immunization coverage among 12–23 month old children from an estimated 62% in 2015–2016 to 76% in 2019–2020. Long-term improvements in coverage will likely require systemic changes to both the supply and demand sides of immunization programs. However, the effect of health system inputs on child vaccination outcomes remains poorly quantified in India. We examined the association between the quality of public health facilities and child vaccination outcomes in rural India using data from the nationally representative Integrated Child Health and Immunization Survey (2015–2016) which covered 1,346 public primary health sub-centers and 44,571 households. We constructed two indices of sub-center quality using multiple correspondence analysis: one related to the general health infrastructure quality and the other measuring vaccine service delivery. Using probit regression, we analyzed the relationship between vaccination outcomes in children under 2 years of age and sub-center quality, controlling for household socioeconomic characteristics. Additionally, we conducted Fairlie decomposition analysis by wealth group — bottom wealth quintile relative to the top four wealth quintiles— to examine factors contributing to gaps in immunization between rich and poor households. Infrastructure quality index was positively associated with completion of seven vaccination outcomes: full immunization, DPT-1 (first dose of diphtheria, pertussis, and tetanus), DPT-2, DPT-3, Bacillus Calmette–Guérin (BCG), hepatitis B (birth dose), and on-time vaccination (OTV). Vaccine service delivery index was positively associated with completion of measles vaccination. The distribution of infrastructure quality contributed to increased gaps in full immunization and OTV between rich and poor households, while greater proximity to vaccination site for poorer households reduced these gaps. Improved quality of health facilities, particularly facilities used by low-income households, may improve vaccination outcomes.     

Induction of HIV-specific antibody response and protection against vaginal SHIV transmission by intranasal immunization with inactivated SHIV-capturing nanospheres in macaques

We have previously reported that concanavalin A-immobilized polystyrene nanospheres (Con A-NS) could efficiently capture HIV-1 particles and that intranasal immunization with inactivated HIV-1-capturing nanospheres (HIV-NS) induced vaginal anti-HIV-1 IgA antibody response in mice. In this study, to evaluate the protective effect of immunization, each three macaques was intranasally immunized with Con A-NS or inactivated simian/human immunodeficiency virus KU-2-capturing nanospheres (SHIV-NS) and then intravaginally challenged with a pathogenic virus, SHIV KU-2. After a series of six immunizations, vaginal anti-HIV-1 gp120 IgA and IgG antibodies were detected in all SHIV-NS-immunized macaques. After intravaginal challenge, one of the three macaques in each of the Con A-NS- and SHIV-NS-immunized groups was infected. Plasma viral RNA load of infected macaque in SHIV-NS-immunized macaques was substantially less than that in unimmunized control macaque and reached below the detectable level. However, it could not be determined whether intranasal immunization with SHIV-NS is effective in giving complete protection against intravaginal challenge. To explore the effect of the SHIV-NS vaccine, the remaining non-infected macaques were rechallenged intravenously with SHIV KU-2. After intravenous challenge, all macaques became infected. However, SHIV-NS-immunized macaques had lower viral RNA loads and higher CD4(+) T cell counts than unimmunized control macaques. Plasma anti-HIV-1 gp120 IgA and IgG antibodies were induced more rapidly in the SHIV-NS-immunized macaques than in the controls. The rapid antibody responses having neutralizing activity might contribute to the clearance of the challenge virus. Thus, SHIV-NS-immunized macaques exhibited partial protection to vaginal and systemic challenges with SHIV KU-2.     

肿瘤疫苗的研究现状

肿瘤在体内的排斥/控制主要依赖于肿瘤抗原特异性T淋巴细胞.T淋巴细胞通过TCR与肿瘤细胞表面表达的HLA-抗原肽复合物的相互作用来识别其靶分子.与特异性HLA-抗原肽复合物有价值的相互作用诱导了淋巴细胞克隆的扩增以及一系列的免疫反应.目前,从理论上已经提出了以整个肿瘤细胞,或纯化的肿瘤抗原作为疫苗(包括整个蛋白质分子和抗原肽及纯化的DNA分子)来提高免疫系统对肿瘤的识别和排斥.本文从免疫系统对肿瘤细胞的识别、疫苗诱导的体内抗肿瘤免疫的假设机制、疫苗接种所诱导的抗肿瘤反应以及临床结果几个方面,对当前肿瘤疫苗的研究现状作一简要综述,并对肿瘤疫苗研究中尚待解决的问题作了简单的归纳.     

产肠毒素大肠杆菌混合载体疫苗的免疫原性评价

本研究在构建表达ETEC菌毛抗原CFA/I、CS6和CS3、融合肠毒素LTB/STm的混合活载体疫苗的基础上 ,以两株福氏志贺载体疫苗 ,同等剂量相混合进行免疫。通过口服免疫 ,该混合多价活疫苗能够诱导机体产生相应的抗ETEC特异的血清和黏膜抗原抗体反应 ,达到了与各单独疫苗株一致的免疫效果 ,同时保持了载体志贺菌自身的免疫原性。     

电针肾俞、膈俞、百会穴对拟血管性痴呆学习记忆障碍小鼠水迷宫实验的影响

目的　观察电针肾俞、膈俞、百会穴对拟血管性痴呆小鼠学习记忆障碍的影响。方法　复制脑缺血再灌注拟血管性痴呆小鼠模型 ,并电针肾俞、膈俞、百会穴 ,分别于术后 7天、15天、30天 ,与药物喜德镇对照 ,采用水迷宫法 ,记录游全程时间、错误次数。结果　造模导致了小鼠学习与记忆能力下降 ,表现为游全程时间延长 ,错误次数增加 ,且随着观察时间的延长 ,这种改变逐渐加重。电针和喜德镇均可使模型小鼠的游全程时间缩短 ,错误次数减少 ,但电针组于 7天和 30天时 ,成绩显著优于药物组。结论　电针肾俞、膈俞、百会穴对模型小鼠学习与记忆能力下降有改善和提高作用     

Immunization with excretory-secretory molecules of intestinal nematodes induces antigen-specific protective memory Th2 cell responses

Parasitic nematodes infect more than 1 billion people in the global south. The development of effective antihelminthic vaccines is a crucial tool for their future elimination. Protective immune responses to nematodes depend on Gata3⁺ Th2 cells, which can also be induced by nematode-released products. Whether these nematode products induce antigen-specific long-lived memory T cells and thereby confer protection against a challenge infection is not known yet. Hence, we set out to characterize the formation of memory Th2 cells induced by immunization with Heligmosomoides polygyrus excretory-secretory (HES) products, infection-induced versus immunization-induced recall responses to a challenge infection, and whether HES-induced memory T cells show protective properties following adoptive transfer. Our results show that 8 weeks postimmunization, HES induces long-lived functional memory Th2 cells at the site of immunization in the peritoneal cavity. Following a H. polygyrus challenge infection, HES-immunized mice display MHC-II-dependent antigen-specific Th2 cytokine responses in the gut-draining lymph nodes, comparable to those induced by a prior natural infection. Moreover, adoptive transfer of sorted memory CD4⁺ T cells from HES-immunized donors reduces female worm fecundity following a challenge H. polygyrus infection in recipient mice, highlighting a protective role for immunization-induced memory T cells.