A single intraduodenal administration of human adenovirus 40 vaccine effectively prevents anaphylactic shock

Human adenoviruses: A suspect behind the outbreak of acute hepatitis in children amid the COVID-19 pandemic

As of 10 May 2022, at least 450 cases of pediatric patients with acute hepatitis of unknown cause have been reported worldwide. Human adenoviruses (HAdVs) have been detected in at least 74 cases, including the F type HAdV41 in 18 cases, which indicates that adenoviruses may be associated with this mysterious childhood hepatitis, although other infectious agents or environmental factors cannot be excluded. In this review, we provide a brief introduction of the basic features of HAdVs and describe diseases caused by different HAdVs in humans, aiming to help understand the biology and potential risk of HAdVs and cope with the outbreak of acute child hepatitis.

A review of 65 years of human adenovirus seroprevalence

Introduction: Human adenovirus (HAdV)-derived vectors have been used in numerous pre-clinical and clinical trials during the last 40 years. Current research in HAdV-based vaccines focuses on improving transgene immunogenicity and safety. Because pre-existing humoral immunity against HAdV types correlate with reduced vaccine efficacy and safety, many groups are exploring the development of HAdV types vectors with lower seroprevalence. However, global seroepidemiological data are incomplete. Areas covered: The goal of this review is to centralize 65 years of research on (primarily) HAdV epidemiology. After briefly addressing adenovirus biology, we chronical HAdV seroprevalence studies and highlight major milestones. Finally, we analyze data from about 50 studies with respect to HAdVs types that are currently used in the clinic, or are in the developmental pipeline. Expert opinion: Vaccination is among the most efficient tools to prevent infectious disease. HAdV-based vaccines have undeniable potential, but optimization is needed and antivector immunity remains a challenge if the same vectors are to be administrated to different populations. Here, we identify gaps in our knowledge and the need for updated worldwide epidemiological data.

Prevalence of serum neutralizing antibodies to adenovirus type 5 (Ad5) and 41 (Ad41) in children is associated with age and sanitary conditions

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Serum neutralizing antibodies to Ad5 and Ad41 in adults and children were titrated.

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Prevalence of NAb in children was associated with age and sanitary conditions.

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NAb titer distribution pattern was very different between Ad5 an Ad41.

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Ad41 vectored vaccine candidates might have a bright future.

Neutralizing antibody (NAb) can dampen the immunogenicity of adenovirus (Ad) vector-based vaccine. Vector systems based on human adenovirus type 41 (Ad41) have been constructed and used to develop recombinant vaccines. Here, we attempted to study the seroprevalence of NAbs to Ad5 and Ad41 among children and adults in Qinghai province, China. The positive rates (titer ⩾ 40) of Ad5 and Ad41 NAb in adults from Xining city were 75.7% and 94.7%, respectively. The moderate/high-positive rates (titer ⩾ 160) of NAb were quite close between the two viruses in adults (70.4% for Ad5 and 73.5% for Ad41). Age-dependent increase of NAb seroprevalence was observed for both viruses in children. NAb-positive rate of Ad41 reached 50% at 3.3–4.6 years of age for children from Chengxi district, Xining city, approximately 1.5 years earlier than that of Ad5 did. Interestingly, NAb level was also associated with sanitary conditions among young children. For Ad5, 8–15% children (0.2–3.0 years of age) from city or town, where the sanitations were relatively better, had moderate/high-positive NAb, while the same rate was 62% for children from villages. For Ad41, 22% children from city, 47% from town and 88% from villages possessed moderate/high-positive NAb. The possible influence of NAb titer distributions on the application of Ad41-vectored vaccines was discussed in detail. Our results suggested that children from places with poor sanitations should be included for comprehensive Ad NAb seroprevalence studies, and provided insights to the applications of Ad41 vectors.