Seroepidemiological investigation of HAdV-4 infection among healthy adults in China and in Sierra Leone, West Africa

Abstract

An apparent increase in the frequency of human adenovirus type 4 (HAdV-4) infections among general populations has been observed over the past 10 years. However, available epidemiological data that may reflect previous viral circulation and assist in predicting potential outbreaks are sparse, particularly in mainland China and Africa. In this study, a convenient neutralization assay for use in the surveillance of historical HAdV-4 infections was established based on a recombinant luciferase-expressing virus. Subsequently, the neutralizing antibodies (nAbs) of 1013 healthy adult serum samples from China and Sierra Leone were evaluated. Our results showed that over 50% of the participants from China and nearly 70% of donors from Sierra Leone had detectable nAbs against HAdV-4 despite the few infection cases officially reported in these regions. Furthermore, the prevalence of nAbs to HAdV-4 is lower than that to HAdV-5, and both varied by geographic location. In addition, the seropositive rates of both HAdV-4 and HAdV-5 nAbs increased with age. However, the nAbs stimulated by HAdV-4 remained stable at low (≤200) levels among the different age groups, whereas moderate (201–1000) or high (>1000) nAb levels were produced by HAdV-5 and tended to decrease with age. These results elucidate the human humoral immune response against HAdV-4 and revealed that this virus may be an underestimated causative agent of respiratory disease among adults in China and West Africa, demonstrating the importance of HAdV-4 surveillance and providing useful insights for the future development of HAdV-4-based vaccines.

Genomics‐based re‐examination of the taxonomy and phylogeny of human and simian Mastadenoviruses: an evolving whole genomes approach, revealing putative zoonosis, anthroponosis, and amphizoonosis

“…In non-captive environments, a survey of human sera that tested positive for antibodies against SAdVs may be paired with a sub-Saharan Africa dataset that reported a PCR-based survey of nonhuman primates to support the hypothesis that cross-species transmissions occur between humans and non-human primates (Xiang et al, 2006;Wevers et al, 2011). Additional reports of cross-species transmission of AdVs include sequence data and/or sero-neutralization data (Ersching et al, 2010;Pauly et al, 2015;Hoppe et al, 2015a;Wang et al, 2018). Again, the importance of these reports is two-fold.…”

Adenoviral Infections in Singapore: Should New Antiviral Therapies and Vaccines Be Adopted?

“…Upon its discovery in the 1950s [15], HAdV-E4 was largely considered restricted to and controlled by vaccine in the US military population, with rare detections among civilians, such as school children in the Netherlands in 1958 [16], users of a private swimming pool in the USA in 1977 [17], and conjunctivitis patients in Japan in 1979 [18]. More recently, surveillance for HAdV has improved, and evidence of HAdV-E4 infections among civilian populations in the USA, Italy, West Africa, China, Hong Kong, Taiwan, India, Malaysia, and Singapore have been increasingly reported [8,[19][20][21][22][23][24][25][26][27][28]. Due to the historical lack of HAdV genotyping surveillance, it is unknown whether HAdV-E4 is a new or re-emerging pathogen in SEA.…”

Epidemiology, Clinical Characteristics, and Prognostic Factors of Atopic Children Hospitalised for Adenovirus Infection: A Single Institutional Study in Shenyang, China

“…Firstly, damage to the airway mucosa after Adv infection and the release of in ammatory mediators can cause bronchial and bronchioles mucosal edema, congestion, necrosis and shedding, necrotic obstruction of the lumen, and bronchial wall edema and thickening, resulting in vasospasm and muscle contraction. Because airway epithelial cells are damaged, its defence capacity is reduced, resulting in allergens invading the airway more easily (14), FAS/FASL expression to promote apoptosis. In the airways of atopic children, damaged neurons in the airway epithelia are exposed, increasing the airway sensitivity (23), and leading to more serious epithelial injury, thus making patients more susceptible to wheezing.…”

“…We are particularly addressing the question of why do some children experience severe symptoms and why do they have a poor prognosis. In recent years, most clinical studies have focused on virus typing (13,14,15), but few studies have assessed the risk factors associated with a poor prognosis. Previous regional studies in Singapore have shown that an Adv type 7 infection, a severe infection requiring invasive or non-invasive ventilation, and a family or personal history of asthma were risk factors for respiratory complications (16).…”