[Influence of the COVID-19 pandemic on the occurrence of neurological infectious diseases]. / Einfluss der COVID-19-Pandemie auf das Auftreten neuroinfektiologischer Erkrankungen.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic a wide range of hygiene measures were implemented to contain the spread of infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Besides a mitigation of SARS-CoV­2, a decline in the number of other respiratory tract infections could be observed. Interestingly, the numbers for some infections of the central nervous system (CNS) decreased as well. OBJECTIVE: This review article shows the development of important CNS infections in Germany during the COVID-19 pandemic. MATERIAL AND METHOD: This article is based on relevant literature on the epidemiology of CNS infections during the COVID-19 pandemic up to autumn 2022. RESULTS: During the COVID-19 pandemic the frequency of bacterial meningitis caused by Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae significantly declined. The frequency of viral meningitis, particularly those caused by Enterovirus, decreased as well. In contrast, the number of patients suffering from tick-borne encephalitis significantly increased within the first year of the pandemic. DISCUSSION: During the pandemic there was a decrease in cases of bacterial and viral meningitis, most likely due to the general containment strategies and social contact restrictions. The increase of infections transmitted by ticks could be a consequence of changed leisure activities during the pandemic.

Increased detection of Echovirus 6-associated meningitis in patients hospitalized during the COVID-19 pandemic, Israel 2021-2022.

BACKGROUND: Outbreaks of enteroviral meningitis occur periodically and may lead to hospitalization and severe disease. OBJECTIVE: To analyze and describe the meningitis outbreak in patients hospitalized in Israel in 2021-2022, during the COVID-19 pandemic. RESULTS: In December 2021, before the emergence of the SARS-CoV-2 omicron variant, an off-season increase in enterovirus (EV) infections was observed among patients hospitalized with meningitis. In January 2022, enterovirus cases decreased by 66% in parallel with the peak of the Omicron wave, and then increased rapidly by 78% in March (compared with February) after a decline in Omicron cases. Sequencing of the enterovirus-positive samples showed a dominance of echovirus 6 (E-6) (29%) before and after the Omicron wave. Phylogenetic analysis found that all 29 samples were very similar and all clustered in the E-6 C1 subtype. The main E-6 symptoms observed were fever and headache, along with vomiting and neck stiffness. The median patient age was 25 years, with a broad range (0-60 years). CONCLUSION: An upsurge in enterovirus cases was observed after the decline of the SARS-CoV-2 omicron wave. The dominant subtype was E-6, which was present prior to the emergence of the omicron variant, but increased rapidly only after the omicron wave decline. We hypothesize that the omicron wave delayed the rise in E-6-associated meningitis.

Decline in the number of patients with meningitis in German hospitals during the COVID-19 pandemic.

BACKGROUND AND OBJECTIVES: In 2020, a wide range of hygiene measures was implemented to mitigate infections caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In consequence, pulmonary infections due to other respiratory pathogens also decreased. Here, we evaluated the number of bacterial and viral meningitis and encephalitis cases during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: In a multicentre retrospective analysis of data from January 2016 until December 2020, numbers of patients diagnosed with bacterial meningitis and other types of CNS infections (such as viral meningitis and encephalitis) at 26 German hospitals were studied. Furthermore, the number of common meningitis-preceding ear-nose-throat infections (sinusitis, mastoiditis and otitis media) was evaluated. RESULTS: Compared to the previous years, the total number of patients diagnosed with pneumococcal meningitis was reduced (n = 64 patients/year in 2020 vs. n = 87 to 120 patients/year between 2016 and 2019, all p < 0.05). Additionally, the total number of patients diagnosed with otolaryngological infections was significantly lower (n = 1181 patients/year in 2020 vs. n = 1525 to 1754 patients/year between 2016 and 2019, all p < 0.001). We also observed a decline in viral meningitis and especially enterovirus meningitis (n = 25 patients/year in 2020 vs. n = 97 to 181 patients/year between 2016 and 2019, all p < 0.001). DISCUSSION: This multicentre retrospective analysis demonstrates a decline in the number of patients treated for viral and pneumococcal meningitis as well as otolaryngological infections in 2020 compared to previous years. Since the latter often precedes pneumococcal meningitis, this may point to the significance of the direct spread of pneumococci from an otolaryngological focus such as mastoiditis to the brain as one important pathophysiological route in the development of pneumococcal meningitis.

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.