Decrease in Enteroviral Meningitis: An Unexpected Benefit of Coronavirus Disease 2019 (COVID-19) Mitigation?

Enteroviral meningitis is seasonal, typically exhibiting a rise in prevalence in late summer/early fall. Based on clinical microbiology laboratory testing data of cerebrospinal fluid, the expected August/September/October peak in enteroviral meningitis did not occur in 2020, possibly related to coronavirus disease 2019 (COVID-19) mitigation strategies.

Viral Meningitis and Encephalitis.

PURPOSE OF REVIEW: This article discusses meningitis and encephalitis infections caused by viruses, excluding herpes family and human immunodeficiency virus (HIV). RECENT FINDINGS: The viral infections of the nervous system detailed in this article have no specific treatment other than supportive care. However, many of the viruses discussed are highly preventable by vaccination, proper skin protection against transmitting vectors, and postexposure prophylaxis. SUMMARY: While meningitis and encephalitis caused by viruses may have some clinical overlap, the management and outcomes can be highly disparate, making distinction between the two imperative. Furthermore, despite their relative rarity in terms of clinical disease, many of the viral infections discussed herein are highly preventable. Given the morbidity and mortality attached to such infections, provider and patient education are the best approach available to prevent these potentially devastating illnesses.

Vaccinations and childhood type 1 diabetes mellitus: a meta-analysis of observational studies.

AIMS/HYPOTHESIS: The aim of this study was to investigate the association between routine vaccinations and the risk of childhood type 1 diabetes mellitus by systematically reviewing the published literature and performing meta-analyses where possible. METHODS: A comprehensive literature search was performed of MEDLINE and EMBASE to identify all studies that compared vaccination rates in children who subsequently developed type 1 diabetes mellitus and in control children. ORs and 95% CIs were obtained from published reports or derived from individual patient data and then combined using a random effects meta-analysis. RESULTS: In total, 23 studies investigating 16 vaccinations met the inclusion criteria. Eleven of these contributed to meta-analyses which included data from between 359 and 11,828 childhood diabetes cases. Overall, there was no evidence to suggest an association between any of the childhood vaccinations investigated and type 1 diabetes mellitus. The pooled ORs ranged from 0.58 (95% CI 0.24, 1.40) for the measles, mumps and rubella (MMR) vaccination in five studies up to 1.04 (95% CI 0.94, 1.14) for the haemophilus influenza B (HiB) vaccination in 11 studies. Significant heterogeneity was present in most of the pooled analyses, but was markedly reduced when analyses were restricted to study reports with high methodology quality scores. Neither this restriction by quality nor the original authors' adjustments for potential confounding made a substantial difference to the pooled ORs. CONCLUSIONS/INTERPRETATION: This study provides no evidence of an association between routine vaccinations and childhood type 1 diabetes.

Childhood meningitis in the conjugate vaccine era: a prospective cohort study.

Bacterial conjugate vaccines have dramatically changed the epidemiology of childhood meningitis; viral causes are increasingly predominant, but the current UK epidemiology is unknown. This prospective study recruited children under 16 years of age admitted to 3 UK hospitals with suspected meningitis. 70/388 children had meningitis-13 bacterial, 26 viral and 29 with no pathogen identified. Group B Streptococcus was the most common bacterial pathogen. Infants under 3 months of age with bacterial meningitis were more likely to have a reduced Glasgow Coma Score and respiratory distress than those with viral meningitis or other infections. There were no discriminatory clinical features in older children. Cerebrospinal fluid (CSF) white blood cell count and plasma C-reactive protein at all ages, and CSF protein in infants <3 months of age, distinguished between bacterial meningitis and viral meningitis or other infections. Improved diagnosis of non-bacterial meningitis is urgently needed to reduce antibiotic use and hospital stay.

Epidemiology of central nervous system infection.

In cases of central nervous system infection, it is crucial for the neuroradiologist to provide an accurate differential diagnosis of the possible pathogens involved so that treating physicians can be aided in the choice of empiric therapy. This approach requires the radiologist to be aware of local epidemiology and have knowledge of infectious agents that are endemic to their area of practice. This article reviews and discusses the changing epidemiology of pathogens most often observed in meningitis, brain abscess, epidural abscess, postoperative infections, and human immunodeficiency virus infection.

Long-term valacyclovir suppressive treatment after herpes simplex virus type 2 meningitis: a double-blind, randomized controlled trial.

BACKGROUND: Herpes simplex virus type 2 (HSV-2) is a common cause of acute and recurrent aseptic meningitis. Our aim was to determine the impact of antiviral suppression on recurrence of meningitis and to delineate the full spectrum of neurological complications. METHODS: One hundred and one patients with acute primary or recurrent HSV-2 meningitis were assigned to placebo (n = 51) or 0.5 g of valacyclovir twice daily (n = 50) for 1 year after initial treatment with 1 g of valacyclovir 3 times daily for 1 week in a prospective, placebo-controlled, multicenter trial. The primary outcome was time until recurrence of meningitis. The patients were followed up for 2 years. RESULTS: The first year, no significant difference was found between the valacyclovir and placebo groups. The second year, without study drugs, the risk of recurrence of verified and probable HSV-2 meningitis was significantly higher among patients exposed to valacyclovir (hazard ratio, 3.29 [95% confidence interval, 10.06-10.21]). One-third of the patients experienced 1-4 meningitis episodes during the study period. A considerable morbidity rate, comprising symptoms from the central, peripheral, and autonomous nervous system, was found in both groups. CONCLUSIONS: Suppressive treatment with 0.5 g of valacyclovir twice daily was not shown to prohibit recurrent meningitis and cannot be recommended for this purpose after HSV meningitis in general. Protection against mucocutaneous lesions was observed, but the dosage was probably inappropriate for the prevention of HSV activation in the central nervous system. The higher frequency of meningitis, after cessation of active drug, could be interpreted as a rebound phenomenon.

Varicella zoster disease of the central nervous system: epidemiological, clinical, and laboratory features 10 years after the introduction of the varicella vaccine.

BACKGROUND: Since the introduction of live attenuated varicella zoster virus (VZV) vaccine in 1995 there has been a significant reduction in varicella incidence and its associated complications, but the impact on VZV-associated central nervous system (CNS) disease has not been assessed. METHODS: In this descriptive study we evaluated patients referred to the California Encephalitis Project from 1998 to 2009 with VZV PCR-positive cerebrospinal fluid (CSF). Epidemiological, clinical, and laboratory data were collected using a standardized case form. Specimens were genotyped using multi-single nucleotide polymorphism (SNP) analysis. RESULTS: Twenty-six specimens were genotyped from patients 12-85 years of age (median, 46 years). Clinical presentations included meningitis (50%), encephalitis (42%), and acute disseminated encephalomyelitis (ADEM) (8%). Only 11 patients (42%) had a concomitant herpes zoster rash. Genotype analysis identified 20 European Group (Clade1, Clade 3) strains; 4 Asian (Clade 2) strains, and 2 Mosaic Group (Clade 4, Clade VI) strains. One specimen was recognized as vaccine strain by identifying vaccine-associated SNPs. CONCLUSIONS: VZV continues to be associated with CNS disease, with meningitis being the most frequent clinical presentation. CNS VZV disease often presented without accompanying zoster rash. Sequencing data revealed multiple genotypes, including 1 vaccine strain detected in the CSF of a young patient with meningitis.

Recurrent meningitis attributable to herpes simplex virus-2 in a child.

A boy manifested episodes of recurrent meningitis that were attributed to herpes simplex virus-2 infection. He presented no concurrent or previous history of involvement of the genitourinary system. He exhibited headaches, dizziness, photophobia, loss of balance, and vomiting. He underwent three episodes of aseptic meningitis. The herpes simplex virus-2 etiology was confirmed by polymerase chain reaction of the cerebrospinal fluid in the last two episodes. After the third occurrence, he was treated with acyclovir. Five years have elapsed since then, without the recurrence of aseptic meningitis.

An overview of meningitis and meningococcal septicaemia.

This article provides an overview of meningitis and meningococcal septicaemia, which can have devastating effects. Nurses working in acute and primary care must be able to recognise the causes and symptoms of these conditions, and have up-to-date knowledge of treatment, prevention and potential after effects.

Epidemiology of meningitis in Oman, 2000-2005.

We reviewed the epidemiologic features and trends for 771 cases of meningitis in Oman from January 2000 to December 2005. We found 69% were bacterial in origin and 13% were viral. Leading bacterial pathogens included Haemophilus influenzae (15%), Streptococcus pneumoniae (14%) and Nesseria meningitidis (12%). For 56% of patients with suspected pyogenic meningitis, no specific bacterial pathogen could be identified. Peak occurrence was in children under 2 years old. The incidence of H. influenzae type b decreased by almost 100% after implementation of the national immunization programme in 2001, while the incidence of cases caused by S. pneumoniae and N. meningitidis remained steady.

Tick-borne encephalitis.

In middle and eastern European countries, tick-borne encephalitis (TBE) is one of the most important human infections of the central nervous system. TBE virus (TBEV) is mainly transmitted by tick bites and rarely by unpasteurized milk. In European countries, TBE presents as meningitis in about 50% of patients, as meningoencephalitis in 40%, and as meningoencephalomyelitis in 10%. The severity of TBE increases with age; in children and adolescents, meningitis is the predominant form of the disease. The long-term prognosis is unfavorable in about 40% to 50% of patients who sustain sequelae for months to years, mainly in terms of pareses, ataxia, and other gait disturbances. No specific treatment for TBE is known. It can be successfully prevented by active immunization.

[Epidemiology and laboratories: the missing link on the plans to study and prevent infectious diseases in Chile]. / Epidemiología y laboratorios: El eslabón perdido en los planes para estudiar y prevenir la enfermedad infecciosa en Chile.

Viral meningitis, hantavirus and Vibrio parahaemolyticus infections are used as examples to demonstrate that important shortcomings and limitations exist in Chile to study the epidemiology of infectious diseases with modern methods. The lack of a national network of well-connected local and national microbiology laboratories is one of these important shortcomings. The author summarizes the evolution of the systems and institutions that deal with the infectious diseases in the world and in Chile.

Recurrent benign lymphocytic meningitis.

Recurrent benign lymphocytic meningitis is a recurring, typically innocuous, painful form of aseptic meningitis. This syndrome is associated with transient neurological symptoms in one-half of afflicted patients. The causative agent is usually herpes simplex virus type 2, which can be confirmed by detection of viral DNA in the cerebrospinal fluid using polymerase chain reaction. Clinical disease resolves spontaneously; however, acyclovir, valacyclovir, and famciclovir have been administered to some patients for both episodic therapy and suppression of recurrences. This therapy is thought to be beneficial, although there is no controlled trial data to support efficacy and safety.

Meningite Viral / Viral Meningitis

A meningite viral caracteriza-se por um quadro clínico de alteração neurológica, que, em geral, evolui de forma benigna. Os casos podem ocorrer isoladamente, embora o aglomerado de casos (surtos) seja comum. Indivíduos de todas as idades são suscetíveis, porém a faixa etária de maior risco é a de menores de 5 anos. Aproximadamente 85% dos casos são devido ao grupo dos Enterovírus, dentre os quais se destacam os Poliovírus, os Echovírus e os Coxsackievírus dos grupos A e B 1,2. O manejo deve ser adequado para cada etiologia. O presente artigo apresenta as principais etiologias, manejo dos casos, possibilidade diagnóstica e tratamento desta importante entidade nosológica.

[Serous meningitis].

During the second half of the 1950s serous meningitis and other enterovirus-induced diseases played one of the leading roles in human pathology in the world. Since the introduction of oral poliomyelitis vaccine (OPV) into wide medical practice from the beginning of the 1960s and during the subsequent decades the number of epidemics and the morbidity level in enterovirus-induced diseases sharply dropped. This was probably due to the interference of enteroviruses circulating in nature and vaccine polioviruses in the intestine of vaccinated children. At the beginning of the XXI century a tendency towards a growth in the morbidity of serous meningitis of enterovirus etiology was noted. This growth was probably due to a sharp decrease in the level of revaccinations of children with OPV. At the age of 2 to 14 years, most affected by enteroviruses, children were not vaccinated with OPV and they were thus left unprotected. The materials on the epidemiology of serous meningitis and recommendations on etiological diagnosis, as well as on the patients hospitalization and the vaccination of children with OPV as a nonspecific antiepidemic measures based on the phenomenon of virus interference are presented.