Seroprevalence and molecular characteristics of varicella-zoster virus infection in Chinese children

Abstract

Background Varicella-zoster virus (VZV) infection in children is an important public health problem in China. We performed the current study to explore the seroprevalence of VZV infection in Chinese children in order to provide more information for improvement of varicella vaccination in China. Methods Three thousand fourteen children were recruited from Chinese kindergarten students aged from four to six years. Anti-VZV IgG and IgM were assayed using enzyme-linked immunosorbent assay. Both ORF22 and ORF62 of VZV were amplified, sequenced, and analyzed by nested PCR. Results Among 3014 children, 43.9% of boys and 46.3% of girls were vaccinated with varicella vaccine, respectively. The seroprevalence of anti-VZV IgG was 54.4% in the children with varicella vaccination, which was significantly higher than those in unvaccinated children (49.2%) (χ 2 = 8.206, P = 0.004). Among of the vaccinated children, the detection rates of VZV IgG antibody increased with age, with 49.4, 50.9 and 58.9% in 4, 5 and 6-year groups, respectively (Trend χ 2 = 17.202, P = 0.002). However, there was no difference in anti-VZV IgG detection rates among those unvaccinated children in different age groups (Trend χ 2 = 8.681, P = 0.070). In addition, 13 boys and 13 girls were positive for anti-VZV IgM, respectively. Among of them, eight children (0.6%) have received varicella vaccination, which was similar to those in unvaccinated children (1.1%). However, only one ORF22 sequence was isolated from an unvaccinated 5-year boy. Compared to the reference VZV sequences, the nucleotide homology was estimated to be 99.7% with genotype J. Conclusions Our study indicated that about half of Chinese children aged four to six years have a high risk of VZV infection. It should be helpful for the evaluation on the necessity of varicella immunization in China.

Spatiotemporal Epidemiology of Varicella in Chongqing, China, 2014–2018

“…Vaccination with live attenuated varicella is a significant and effective way to control the varicella epidemic and offer protection against varicella [35][36][37]. Due to the principle of voluntary choice and self-funded payments, and the neglected risk of varicella compared to other infectious diseases such as measles and mumps, the vaccination rate in many parts of China is relatively low and does not reach the 80% level that the World Health Organization recommends [32,33,38,39]. Therefore, the immunity barrier is insufficient for susceptible persons, especially in relatively underdeveloped regions.…”

Detection of Circulating VZV-Glycoprotein E-Specific Antibodies by Chemiluminescent Immunoassay (CLIA) for Varicella–Zoster Diagnosis

“…Reliable assays in the immunological diagnosis of VZV with the best performance are essential in the era of vaccine program implementation, their effectiveness evaluation, and for VZV-associated disease monitoring [12,14,[18][19][20]23]. Most laboratories currently diagnose VZV-associated diseases from patient clinical symptoms, which is biased and may result in misdiagnoses identifying other (herpesvirus) infections with similar symptoms, such as HSV [25,37].…”

“…Moreover, similar to other commercial immunological tests, PCR-based diagnostics are not widely available [12], and it is expensive and leads to patient compliance [47]. Altogether, our CLIA-based diagnostic tests filled these gaps and would be helpful in public health laboratories for routine varicella-zoster disease diagnosis, control outbreak situations [12], and varicella-zoster seroepidemiological studies for vaccine implementation purposes [14,[18][19][20]23].…”

“…However, many reports hypothesized that the implementation of varicella vaccines would be followed by an increase in post-vaccine varicella or herpes zoster cases [2,9,10,[16][17][18], suggesting the need for using antibody detection tests in routine diagnoses for global epidemiologic surveillance, along with herpes zoster vaccination [17]. For instance, in many other countries, such as China [18][19][20] and Norway [21], where anti-VZV vaccines are not yet implemented or where VZV vaccination coverage is uneven, rapid case identifications are crucial [19,21,22]. Reporting varicella cases in these countries, especially in high-frequented public areas such as schools, institutions, healthcare centers, hospitals, etc., would prevent rapid infection spread to people at risk (pregnant women, immunocompromised).…”

Evaluation of Varicella-Zoster Virus Immunoglobulin G in Children With Malignancies on Chemotherapy

“…In 2020, Zawitkowska et al found that 29.4% of the pediatric population with ALL were seropositive (9). Luan et al revealed that among 3,014 studied children in China, more than 54% with varicella vaccination were anti-VZV IgG-positive (16). In 2016, Ojha et al found that the incidence rate of VZV infection was 2.3% among patients with pediatric cancer in developing countries (17).…”