Measles Sclerosing Subacute PanEncephalitis (SSPE), an intriguing and ever-present disease: Data, assumptions and new perspectives

Factors associated with measles vaccine immunogenicity in children at University Teaching Hospitals, Lusaka, Zambia

Measles poses a significant global public health challenge, particularly in low-resource settings where vaccination coverage is limited. This study examined factors associated with measles vaccine immunogenicity in children aged 2-15 years at the University Teaching Children's Hospital and the HIV Pediatric Centre of Excellence in Lusaka, Zambia. This comparative analytical cross-sectional study was conducted from April to July 2024, enrolling 200 children, including 100 HIV-positive and 100 HIV-negative participants. All children had received at least two doses of a measles-containing vaccine and had no history of measles infection in the past six months. Blood samples were analyzed for measles immunity, while data on age, HIV status, breastfeeding history, and socio-demographic factors were collected. Among HIV-negative children, 75% retained immunity, whereas only 38% of HIV-positive children retained immunity. Multivariate logistic regression showed that children aged 10-15 years were less likely to retain immunity compared to those aged 2-4 years (AOR = 0.270, 95% CI [0.114-0.618], p = 0.002). HIV-positive children had lower odds of retaining immunity compared to HIV-negative children (AOR = 0.290, 95% CI [0.137-0.594], p < 0.001). Breastfed children had higher immunity retention (AOR = 0.336, 95% CI [0.147-0.738], p = 0.007) compared to non-breastfed children. Residing in Lusaka was associated with lower immunity retention (AOR = 0.250, 95% CI [0.066-0.859], p = 0.031). These findings highlight the protective role of breastfeeding and suggest that older and HIV-infected children may benefit from booster doses to sustain measles immunity.

Exploring the role of the IL-12/IFN-γ immune axis in subacute sclerosing panencephalitis

BACKGROUND

Subacute sclerosing panencephalitis (SSPE) is a rare but fatal neurological syndrome resulting from persistent measles virus infection in the central nervous system. Despite the availability of a measles vaccine, SSPE continues to pose a significant health burden, and immunogenetic risk factors remain unclear. We aimed to study the role of the interleukin 12 (IL-12)/interferon-gamma (IFN-γ) axis, known for it's significance in antiviral defense, in the development of SSPE.

METHODS

This cross-sectional case-control study recruited consecutive age and sex-matched SSPE cases (n = 51) and controls (n = 51). Gene expressions were quantified for IL-12B, IFNG, IL-12RB1, STAT4, IFNGR1, IFNGR2, STAT1, IRF8, and ISG15 genes using quantitative realtime PCR. Additionally, plasma levels of IL-12p40, IL-12p70, and IFN-γ were measured using the multiplex suspension array platform. Furthermore, single nucleotide polymorphisms (SNPs) in IL-12B, IL-12RB1, IFNG, IFNGR1, IFNGR2, and ISG15 genes were examined using TaqMan SNP genotyping assays. Statistical analyses compared gene expressions, cytokine levels, and alleles and genotypes frequencies between SSPE patients and controls.

RESULTS

Significant alterations in the expression of key IL-12 pathway-related genes were observed in SSPE patients compared to controls, including lower STAT4 (p = 0.0445) and higher IFNGR1 (p = 0.0005) and IRF8 (p = 0.0229). Elevated plasma levels of IL-12p70 (p = 0.0015) and IFN-γ (p = 0.0381) were also observed in SSPE patients. Additionally, associations with SSPE were found for the rs3212227 SNP in IL-12B (p = 0.048), the rs1059293 SNP in IFNGR2 (p = 0.052), and the rs1921 SNP in ISG15 (p = 0.054) genes. Notably, gene-gene interactions among these genes exhibited associations with SSPE.

CONCLUSION

This study provides novel insights into the dysregulation of the IL-12/IFN-γ immune axis in SSPE and underscores the complex interplay between host genetics and viral infection in disease pathogenesis.

Subacute Sclerosing Panencephalitis: Impact on Public Health, Current Insights, and Future Perspectives

BACKGROUND

Subacute Sclerosing Panencephalitis (SSPE) is a rare complication of the measles infection. SSPE is a chronic disease of the central nervous system (CNS) that causes encephalitis, leading to the demyelination of neurons in the brain. It affects the brain in 9 months or less and hence subacute, causing encephalitis and lesions in the entire brain, so the term panencephalitis is used.

METHODS

A comprehensive literature search was conducted using the databases PubMed and Google Scholar starting in April 2024, and all relevant articles were extracted for this review.

RESULTS

A recent surge in SSPE cases in developed countries has been reported. This has been attributed to reduced vaccination, aggravated by misinformation and a decline in immunization after the COVID-19 pandemic. SSPE is a progressive and relatively rare neurological complication of measles, which almost always results in a vegetative state followed by death. It typically presents 10 years following exposure to measles. Manifestations of SSPE are divided into four stages that range from general personality changes to coma. Complications include ocular pathology and eventual blindness, as well as psychiatric illnesses. Treatment options for SSPE include symptomatic control with antiepileptic drugs, interferon combined treatment, vitamin A, ribavirin, and a ketogenic diet for disease modification.

CONCLUSION

The only prevention for SPPE is through vaccination. Several collaborative efforts have been made with WHO to improve surveillance and increase vaccination, but still many challenges prevail. Better prevention strategies and improved treatment outcomes can only be achieved by enhancing healthcare access, improving public awareness, analyzing community-based data, and studying the genetic and molecular associations of measles and SSPE.

Neuroimaging Abnormalities in Patients with Subacute Sclerosing Panencephalitis : Prospective Follow-up Study

OBJECTIVE

This study aimed to assess the neuroimaging abnormalities and their progression in patients with Subacute sclerosing panencephalitis (SSPE) and identify clinical predictors of these imaging findings.

METHODS

This prospective observational study evaluated clinical and neuroimaging features in patients with SSPE. Patients were categorized using Dyken's criteria, Jabbour's staging system, and the definition of fulminant SSPE. They underwent comprehensive clinical assessments, cerebrospinal fluid examination, Electroencephalogram (EEG), and Magnetic Resonance Imaging (MRI) scans. Treatment involved intrathecal interferon‑α and antiepileptic medications. Functional disability was assessed using the modified Barthel index. Follow-ups were performed at 6 months, including reassessment of Modified Barthel Index (MBI) and Jabbour's staging and EEG and MRI scans.

RESULTS

The mean age was 13.9 ± 6.7 years, with males comprising 81.5% (44/54) of the cohort. Fulminant SSPE was noted in 33% (18/54) of cases. Disease duration before presentation varied significantly between fulminant and non-fulminant forms (p = 0.001). Neuroimaging abnormalities were more prevalent in JS III stage patients, with diffuse cerebral atrophy being a significant finding (p = 0.011). Basal ganglia involvement correlated with movement disorders. The 6‑month follow-up showed increased cerebral atrophy (p = 0.004). Increasing disease duration was an independent predictor of cerebral atrophy. An Intercomplex interval (ICI) of more than 10 minutes correlated with normal neuroimaging, 10 patients died within the study period, 8 of whom had fulminant SSPE.

CONCLUSION

Parieto-occipital White matter hyperintensity (WMH) is the most prevalent and sensitive neuroimaging finding for the diagnosis of SSPE. Despite interferon treatment, cerebral atrophy progressed in both aggressive and fulminant SSPE. Increasing disease duration is an independent predictor of cerebral atrophy.

What's going on with measles?

Measles is a highly transmissible systemic viral infection associated with substantial mortality primarily due to secondary infections. Measles induces lifelong immunity to reinfection but loss of immunity to other pathogens. An attenuated live virus vaccine is highly effective, but lapses in delivery have resulted in increasing cases worldwide. Although the primary cause of failure to control measles is failure to vaccinate, waning vaccine-induced immunity and the possible emergence of more virulent virus strains may also contribute.

Patients With Subacute Sclerosing Panencephalitis in Japan: A 2022 Nationwide Survey

BACKGROUND

In Japan, the incidence of subacute sclerosing panencephalitis (SSPE) has reduced; however, the medical conditions and factors associated with disease progression remain unclear.

METHODS

A nationwide survey of SSPE was conducted using a questionnaire in 2022. We conducted a descriptive analysis of the patients with SSPE in 2022 and Cox proportional hazards analyses for disease progression. We compared the patients with SSPE with those in a 2007 survey.

RESULTS

A total of 37 surviving patients with SSPE were enrolled [median age: 32 years (range: 16-52 years)]. No new cases have been identified since 2017 in the survey. Jabbour stage IV was the most common stage (66.7%). The hazard ratios (95% confidence intervals) of male sex and age at the time of measles infection (years) were 2.56 (1.13-5.76) and 0.57 (0.34-0.93), respectively. Compared with those in 2007, the proportion of patients in hospitals decreased from 13.7% to 2.7%, whereas that of patients in nursing facilities increased from 17.6% to 29.7%. The proportions of patients prescribed inosine pranobex, interferon and ribavirin at the time of the survey decreased from 96.1% to 79.4%, 74.8% to 14.3% and 25.3% to 0%, respectively. The proportions of patients with gastrostomy, tracheostomy and ventilator use increased from 5.9% to 69.7%, 23.3% to 60.0% and 10.8% to 32.4%, respectively.

CONCLUSIONS

Decreased measles cases in Japan reduced new SSPE cases. However, surviving patients in 2022 had advanced disease stages and needed medical care. Male sex and early measles infection were significantly associated with disease progression.

La panencéphalite sclérosante subaiguë de la rougeole

La panencéphalite sclérosante subaiguë (PESS), une complication tardive de la rougeole, est encore présente lors d’épidémies de cette maladie dues aux insuffisances de la vaccination. Après un rappel historique, nous aborderons la physiopathologie de la PESS et l’importance des critères diagnostiques. De nombreux travaux portant sur les paramètres de l’immunité innée et sur ceux des réponses interféron tendent à montrer une baisse de l’activité de l’immunité cellulaire au cours de cette maladie. Nous formulons ici plusieurs hypothèses s’appuyant sur des publications concernant différentes formes de la maladie : congénitales, périnatales, formes à incubation courte, semblables à l’encéphalite aiguë à inclusions (EAI), formes d’évolution rapide, formes retrouvées chez les immunodéprimés ou chez l’adulte. Des formes familiales ont également été identifiées, suggérant une origine génétique. Selon la durée de la période de latence entre rougeole et la PESS, deux groupes de patients ont été individualisés, incitant à des analyses rétrospective et prospective des exomes de ces malades. La connaissance des gènes participant à la maladie devrait être utile pour la compréhension de la physiopathologie de la PESS mais aussi d’autres infections neurologiques tardives dues à des virus à ARN.

Options in the Treatment of Subacute Sclerosing Panencephalitis: Implications for Low Resource Areas

Purpose of the review

Subacute sclerosing panencephalitis (SSPE) is a rare, slowly progressive, and frequently fatal neurodegenerative disorder caused by measles virus. The risk of SSPE remains significant globally, with fluctuating incidence noted in in tandem with measles vaccine uptake. This review aims to explore the current global status of SSPE, its treatment, and preventive measures.

Recent findings

An increase in measles cases have been reported in various parts of the world for different reasons related to the regional context of the outbreak. With reduction in measles vaccine doses since the onset of the COVID-19 pandemic, the future risk of SSPE can only accelerate. In recent years, subsequent cases of SSPE have been reported in the period following documented measles outbreaks in different settings. Concomitantly, there have been efforts to evaluate the efficacy of immunomodulatory, antiviral, and anti-seizure therapies that could ameliorate the devastating effects of this disease. This review elucidates on these approaches and their limitations, reasons for poor vaccine coverage in low- and middle-income countries, as well as the possible solutions to the prevention of measles and eventual avoidance of SSPE.

Summary

Prevention of measles virus infection with the resultant sequelae would be the most effective strategy for the management of SSPE. This approach would be particularly important in low resource setting that currently bears the double burden of widespread communicable diseases and malnutrition.