Ongoing sporadic monkeypox cases: neutralising antibody detection in asymptomatic individuals

Mpox in children and adolescents and contact follow-up in school settings in greater Paris, France, May 2022 to July 2023

BackgroundDuring the 2022 mpox outbreak in Europe, primarily affecting men who have sex with men, a limited number of cases among children and adolescents were identified. Paediatric cases from outbreaks in endemic countries have been associated with a higher likelihood of severe illness. Detailed clinical case descriptions and interventions in school settings before 2022 are limited.AimTo describe clinical characteristics of mpox cases among children (< 15 years) and adolescents (15-17 years) in the greater Paris area in France, and infection control measures in schools.MethodsWe describe all notified laboratory-confirmed and non-laboratory-confirmed cases among children and adolescents identified from May 2022 to July 2023, including demographic and clinical characterisation and infection control measures in school settings, i.e. contact tracing, contact vaccination, secondary attack rate and post-exposure vaccination uptake.ResultsNineteen cases were notified (13 children, 6 adolescents). Four adolescent cases reported sexual contact before symptom onset. Ten child cases were secondary cases of adult patients; three cases were cryptic, with vesicles on hands, arms and/or legs and one case additionally presented with genitoanal lesions. Five cases attended school during their infectious period, with 160 at-risk contacts identified, and one secondary case. Five at-risk contacts were vaccinated following exposure.ConclusionCases among children and adolescents are infrequent but require a careful approach to identify the source of infection and ensure infection control measures. We advocate a 'contact warning' strategy vs 'contact tracing' in order to prevent alarm and stigma. Low post-exposure vaccination rates are expected.

T Cell Responses against Orthopoxviruses in HIV-Positive Patients

A global outbreak of predominantly sexually transmitted mpox infections, outside endemic regions, was reported in May 2022. Thereafter, risk groups were vaccinated against smallpox, a structurally related orthopoxvirus. In the current study, we analyzed T cell responses against peptides derived from orthopoxviruses in 33 HIV-positive patients after two vaccinations against smallpox and in 10 patients after mpox infection. We established an ELISpot assay, detecting either the secretion of the pro-inflammatory cytokine interferon (IFN)-γ or interleukin (IL)-2. After vaccination, 21 out of 33 patients (64%) showed specific IFN-γ secretion and 18 (55%) specific IL-2 secretion, defined as >3-fold higher specific value than negative control and at least 4 spots above the negative control. After mpox infection, all patients showed specific IFN-γ secretion and 7 out of 10 (70%) IL-2 secretion. In vaccinated patients, IFN-γ responses were significantly lower than in patients with mpox infection (median response 4.5 vs. 21.0 spots, p < 0.001). The same trend was observed for IL-2 responses. After mpox infection, IL-2 ELISpot results positively correlated with CD8+ T cells (p < 0.05). Thus, T cell responses were detectable in two thirds of HIV-positive patients after vaccination and were even more abundant and vigorous after mpox infection.

Monkeypox virus (MPXV): A Brief account of global spread, epidemiology, virology, clinical features, pathogenesis, and therapeutic interventions

The largest monkeypox virus (MPXV) outbreak of the 21st century occurred in 2022, which caused epidemics in many countries. According to WHO, physical contact with infected persons, contaminated surfaces, or affected animals might be a source of this virus transmission. A febrile sickness including few symptoms found in MPX disease. Skin rash, lesions, fever, headache, fatigue, and muscle aches symptoms were observed commonly for this disease. Animal and in vitro, studies have shown that the antiviral medications cidofovir and brincidofovir are effective against MPXV. The first-generation vaccinia virus vaccine was developed in 1960, and it helped to protect against MPXV with its side effects. A second-generation vaccination with limitations was launched in 2000. However, the CDC advised vaccinations for risk groups in endemic countries, including positive patients and hospital employees. The JYNNEOS vaccine, administered in 2 doses, also provides protection from MPX. This article presents concisely the most recent findings regarding epidemiology, genomic transmission, signs and symptoms, pathogenesis, diagnosis, and therapeutic interventions for MPXV, which may be helpful to researchers and practitioners. WHO declared that MPX was no longer a global health emergency due to its declining case rate, and a number of countries have reported new incidences. Further research-based investigations must be carried out based on the 2022 outbreak.