Human Coronavirus NL63 and 229E Seroconversion in Children

Abstract

In 2004, the novel respiratory human coronavirus NL63 (HCoV-NL63) was identified, and subsequent research revealed that the virus has spread worldwide. HCoV-229E is a close relative of HCoV-NL63, and infection with either virus can lead to the hospitalization of young children, immunocompromised persons, and the elderly. Children infected with HCoV-NL63 often develop croup, with obstruction of the airway. In this study we investigated at which age children are confronted for the first time with an HCoV-NL63 infection and, thus, at which age they seroconvert to HCoV-NL63 positivity. We designed a recombinant HCoV-229E and a recombinant HCoV-NL63 nucleocapsid protein enzyme-linked immunosorbent assay and performed a seroepidemiology survey on longitudinal and cross-sectional serum samples. The longitudinal serum samples were collected from 13 newborns, and data for those newborns were available from multiple time points spanning a period of at least 18 months. For the cross-sectional survey we tested serum samples of 139 children, including newborns to children 16 years of age. In examinations of the longitudinal serum samples we observed that all of the children had maternal anti-NL63 and anti-229E antibodies at birth that disappeared within 3 months. Seven of the 13 children became HCoV-NL63 seropositive during follow-up, whereas only 2 became HCoV-229E seropositive. The serology data of the cross-sectional serum samples revealed that 75% and 65% of the children in the age group 2.5 to 3.5 years were HCoV-NL63 and HCoV-229E seropositive, respectively. We conclude that on average, HCoV-NL63 and HCoV-229E seroconversion occurs before children reach the age of 3.5 years.

Human coronavirus NL63 infections in infants hospitalised with acute respiratory tract infections in South Africa

“…HCoV‐NL63 infections appear to be seasonal; 67% of infections occurred during autumn. No HCoV‐NL63 infection was detected during the winter months in either 2003 and 2004, a finding also noted in the ambulatory population 9 This pattern differs from that previously reported where HCoV‐NL63 infection was predominantly found during the winter season 6,15–19,21,22 . Detection during early spring and summer indicates that HCoV‐NL63 may circulate at low levels throughout the year.…”

“…HCoV‐NL63 was found to circulate in infants and young children in both 2003 and 2004 with similar low prevalence rates of 0·8%. This finding is lower than that reported in previous studies where detection of HCoV‐NL63 ranged from 1% to 7·3% 6,7,15–20 although higher prevalences of 8·8% and 9·3% have also been reported 21,22 . Most HCoV‐NL63‐positive children (75%) were under 6 months, indicating that this younger age group may be more susceptible to severe infections requiring hospitalisation; a finding supported by other studies where 38/76 (50%), 4/5 (80%) and 11/12 (92%) of HCoV‐NL63 infections occurred in this age group respectively 7,19,21 .…”

Burden of disease due to human coronavirus NL63 infections and periodicity of infection

“…E-mail address: c.m.vanderhoek@amc.uva.nl (L. van der Hoek). terdam, the Netherlands, 6 but it soon turned out that HCoV-NL63 infection occurs frequently in children, [8][9][10] is observed around the globe (reviewed in Ref. 11), and infection is associated with croup and acute otitis media.…”

Infection with human coronavirus NL63 enhances streptococcal adherence to epithelial cells

“…Human coronavirus NL63 (HCoV-NL63) is a relatively recently discovered human respiratory pathogen with a high worldwide prevalence (Fouchier et al, 2004;Golda & Pyrc, 2008;Hofmann et al, 2005;Pyrc et al, 2004Pyrc et al, , 2006Pyrc et al, , 2007aPyrc et al, , b, 2008Schildgen et al, 2006;van der Hoek et al, 2004. Arguably, HCoV-NL63 is among the most clinically important human coronaviruses and is associated with upper and lower respiratory tract infections, occurring most frequently in the winter season and presenting more severe symptoms in children, the elderly and immunocompromised patients (Bastien et al, 2005;Chiu et al, 2005;Dijkman et al, 2008;Kaiser et al, 2005;Suzuki et al, 2005;Vabret et al, 2005;Wu et al, 2008). HCoV-NL63 is currently considered to be the major pathogen involved in the development of croup in young children (van der .…”