The successful containment of coxsackie B4 infection in a neonatal unit

The epidemiology of aseptic meningitis in New Zealand children from 1991 to 2020

AIM

Aseptic meningitis, including culture negative and viral meningitis, contributes a significant health-care burden, including unnecessary antibiotic use and hospitalisation to treat possible bacterial meningitis. This study analysed aseptic meningitis hospitalisations in New Zealand (NZ) children over 29 years.

METHODS

In this population-based study, aseptic meningitis hospitalisations in NZ children <15 years old were analysed from 1991 to 2020. Incident rate ratios were calculated using Poisson regression models. Variations in hospitalisations by age, year, sex, ethnicity, geographical region and socio-economic deprivation were analysed.

RESULTS

There were 5142 paediatric aseptic meningitis hospitalisations from 1991 to 2020. Most were unspecified viral meningitis (64%), followed by enterovirus (29%). Hospitalisation rates varied annually with a median of 18.4/100 000 children including a peak in 2001 of 56.4/100 000 (51.7-61.6). From 2002 to 2019, rates increased by 8.4%/year (7.2-9.5%) in infants <90 days old but decreased in all other age groups. In 2020, a reduction in hospitalisations to 9.6/100 000 (7.9-11.8) occurred, and in infants <90 days old were 0.37 times expected. Hospitalisations were 1.50 times (1.49-1.68) higher in males than females; higher in children of Māori (P < 0.001) and Pacific (P < 0.001) versus European ethnicity; and higher for children living in the most (2.44 times, (2.16-2.75)) versus least deprived households; and in northern versus southern NZ.

CONCLUSIONS

Aseptic meningitis hospitalisations increased in young infants during 29 years of surveillance, apart from 2020 when admissions reduced during the COVID-19 pandemic. In contrast, hospitalisations decreased in children aged >1 year. Further investigation into reasons for higher admissions by ethnic group, geographical location and increased deprivation are required.

Presentation, diagnosis, and management of enterovirus infections in neonates

The nonpoliovirus enteroviruses commonly infect newborns, with consequences ranging from asymptomatic infection and benign illness, to severe, life-threatening disease. Frequently occurring symptoms include fever, irritability, lethargy, anorexia, and rash. Although most illnesses are mild, severe disease develops in a subset of newborns infected in the first 2 weeks of life. Severe disease may consist of sepsis, meningoencephalitis, myocarditis, pneumonia, hepatitis, and/or coagulopathy. Substantial mortality rates have been reported, and long-term sequelae may occur among survivors. Risk factors and clinical features associated with severe disease include absence of neutralizing antibody to the infecting serotype, maternal illness prior to or at delivery, prematurity, illness onset within the first few days of life, multiorgan disease, severe hepatitis, positive serum viral culture, and specific infecting serotype (e.g. group B coxsackieviruses and echovirus 11). Whereas the mainstay of diagnosis has traditionally been viral isolation in tissue culture, the polymerase chain reaction has been demonstrated to be more sensitive than culture, highly specific, and rapid. Immunoglobulin has been used as a therapeutic agent for neonates with enterovirus disease; however, clinical efficacy has not been proven. Specific antiviral therapy for enteroviruses is in development. Pleconaril is an investigational agent that inhibits viral attachment to host cell receptors and uncoating of viral nucleic acid. It has broad and potent anti-enterovirus activity, excellent oral bioavailability, and is well tolerated. Some clinical trials have demonstrated benefit in children and adults with enterovirus meningitis, and in adults with upper respiratory tract infections caused by picornaviruses (rhinoviruses or enteroviruses). Data summarizing compassionate use for severe enterovirus diseases (including neonatal sepsis) also suggest possible benefit. Limited pharmacokinetic data are available in infants and neonates. A multicenter, placebo-controlled, randomized trial of pleconaril in neonates with severe hepatitis, coagulopathy, and/or myocarditis is currently being conducted.

Coxsackievirus B3 sequences in the blood of a neonate with congenital myocarditis, plus serological evidence of maternal infection

A fatal case of myocarditis in a neonate is described. The clinical features were evident at birth, and enteroviral RNA was detected in the blood of the baby on the day of birth and again 10 days later by a generic enterovirus nested reverse transcription-polymerase chain reaction (RT-PCR) assay. The enterovirus RNA was subsequently retested by a separate, newly developed nested RT-PCR assay yielding a PCR product within the VP1 coding region suitable for sequencing. Identical 239-base pair sequences were obtained from the RNA of the two blood samples and this sequence most closely resembled coxsackievirus B3 (94% identity). The baby's mother was pyrexial immediately postpartum and an early antenatal serum and a serum sample collected 10 days postpartum tested in parallel for enterovirus IgM antibody showed negative to strong-positive seroconversion. Infection of the mother was the likely primary event with in utero transfer of the virus to the fetus in the last few days of pregnancy. Neonatal blood is a valuable specimen for enterovirus diagnosis by RT-PCR. A newly developed nested RT-PCR assay was successful in typing the enterovirus from stored RNA extracted directly from the blood samples. Serology for enterovirus IgM antibody can be useful for convalescent diagnosis of enterovirus infection in the mother, especially with earlier serum for comparison.