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Haemophilus ducreyi (HD) is an important cause of cutaneous ulcers in several endemic regions, including the Western Pacific Region, especially among children. An HD sequence typing on swab samples taken from 1,081 ulcers in the Namatanai district of Papua New Guinea, during the pilot study for treatment of yaws, has been performed using the Grant typing system. Of the 363 samples that tested positive for the 16S rDNA of HD, the dsrA sequences of 270 samples were determined. Altogether they revealed 8 HD strain types circulating in Namatanai, including seven strain types of Class I (I.3, I.4, I.5, I.9, I.10, I.11, I.12) and one strain of Class II (II.3); four Class I types (I.9, I.10, I.11, I.12) were novel. The southern region of Namatanai (Matalai Rural) was identified as the region with the lowest genotype diversity and with most infections caused by HD Class II. The middle and northern subdistricts were affected mainly by HD Class I. Analysis of patient characteristics revealed that Class II HD infections were more often represented by longer-lasting ulcers than Class I HD infections. An increase in the prevalence of the I.10 strain was found after azithromycin administration compared to the untreated population at baseline likely reflecting higher infectivity of HD Class I, and more specifically strain type I.10. Author summary: Haemophilus ducreyi (HD) is one of the main causative agents of cutaneous ulcers in children across substantial parts of Africa and the Pacific. A yaws eradication study conducted in the Namatanai district of Papua New Guinea revealed that nearly one-third of all patients were infected with HD. Single locus sequence typing (SLST) of the HD dsrA locus revealed presence of multiple HD strains circulating in the human population of Namatanai region. In contrast to Treponema pallidum subsp. pertenue, the pathogen responsible for yaws, the prevalence of HD strains did not significantly decrease following mass drug administration. In addition, HD strains from patients in Namatanai region revealed a higher genetic diversity compared to the yaws agent present in the same area and the HD strain composition changed following antibiotic treatment. Infections caused by at least some different HD strain types appear to differ in reported ulcer duration and also in resurgence of infection after antibiotic treatment. Therefore, important pathophysiological differences among HD strain types were predicted. [ABSTRACT FROM AUTHOR]

Since May, 2022, a large global outbreak of human mpox (formerly known as monkeypox) has predominantly affected men who have sex with men. The strain responsible, Clade IIb, has mutated substantially from precursors originating from the 2017–18 outbreak in Nigeria. Immunity to smallpox, another orthopoxvirus, via previous infection or vaccination provides lifelong immunity. However, since the 2022 mpox outbreak, recent clusters were described in individuals with presumed immunity through recent infection or vaccination. We aim to describe the epidemiological and clinical characteristics of mpox in individuals with past infection or vaccination to improve the understanding of this disease in the setting of previous immunity. In this global case series, international collaborators from nine countries provided data on individuals with PCR-confirmed mpox after documented previous infection or vaccination between May 11, 2022, and June 30, 2023. We excluded cases that could not confirm vaccination status or cases with partial immunisation or any doses received before the current multi-national mpox outbreak (cutoff date May 1, 2022). Data were collected via a case report spreadsheet that reported on dates of infection and vaccination, route of immunisation, demographic characteristics, clinical findings, HIV status, concomitant sexually transmitted infections, and markers of disease severity (mpox severity score system). We describe case epidemiology, clinical course, and mpox severity scores; all analyses were descriptive. We report mpox infections in 37 gay and bisexual men who have sex with men: seven individuals had mpox reinfections, 29 individuals had mpox infections that occurred after two appropriately spaced Modified Vaccinia Ankara-Bavarian Nordic vaccine courses, and one individual had an infection that met the criteria for both reinfection and infection after vaccination. The median age of individuals was 36 years (IQR 30–45; range 21–58). Those with natural immunity after initial infection had a shorter disease course with less mucosal disease upon reinfection than with their initial infection. Infections post-vaccination were characterised by few lesions, little mucosal disease, and minimal analgesia requirements; two people received oral tecovirimat. Overall, there were no deaths, no bacterial superinfections, and all individuals were managed in the ambulatory clinic with one hospital admission for a necrotising neck lesion. The epidemiology of people with mpox reinfection or infection post-vaccination was similar to other published cohorts during the 2022 outbreak—predominantly young, sexually active gay and bisexual men who have sex with men. Clinical features and outcomes of repeat infection and infection after vaccination appear to be less clinically severe than those described in 2022 case literature. Specifically, compared with the 2022 case series, these individuals in the present study had fewer confluent lesions, less mucosal involvement, reduced analgesia requirement, and fewer admissions. Natural immunity and vaccine-induced immunity are not fully protective against mpox infection. However, in this small series both disease duration and severity appear to be reduced. None. [ABSTRACT FROM AUTHOR]

Background: Since the emergence of the global mpox outbreak in May, 2022, more than 90 000 cases have been diagnosed across 110 countries, disproportionately affecting people with HIV. The durability of mpox-specific immunity is unclear and reinfections have been reported. We aimed to compare mpox immune responses up to 6 months after diagnosis in participants with and without HIV and assess their effect on disease severity and viral clearance dynamics., Methods: This study was embedded within a prospective, observational, multicentre cohort study of viral clearance dynamics among people with mpox in Spain (MoViE). We included women and men aged 18 years or older, who had signs of mpox, and reported having symptom onset within the previous 10 days at the moment of mpox diagnosis from three sex clinics of the Barcelona metropolitan area. Samples from skin ulcers were collected weekly to estimate the time to clear monkeypox virus (MPXV) from skin lesions. Blood samples were taken at diagnosis, 29, 91, and 182 days later for immune analysis. This included quantifying IgG and IgA against three mpox antigens by ELISA, evaluating in-vitro neutralisation, and characterising mpox-specific T-cell responses using interferon γ detecting enzyme-linked immunospot (ELISpot) assay and multiparametric flow cytometry., Findings: Of the 77 originally enrolled participants, we included 33 participants recruited between July 19, and Oct 6, 2022. Participants without HIV (19 [58%] participants) and participants with HIV (14 [42%] participants) had similar clinical severity and time to MPXV clearance in skin lesions. Participants with HIV had a CD4 + T-cell count median of 777 cells per μL (IQR 484-1533), and 11 (78%) of 14 were virally suppressed on antiretroviral therapy. Nine (27%) of 33 participants were age 49 years or older. 15 (45%) of 33 participants were originally from Spain, and all participants were men. Early humoral responses, particularly concentrations and breadth of IgG and IgA, were associated with milder disease and faster viral clearance. Orthopoxvirus-specific T cells count was also positively correlated with MPXV clearance. Antibody titres declined more rapidly in participants with HIV, but T-cell responses against MPXV were sustained up to day 182 after diagnosis, regardless of HIV status., Interpretation: Higher breadth and magnitude of B-cell and T-cell responses are important in facilitating local viral clearance, limiting mpox dissemination, and reducing disease severity in individuals with preserved immune system. Antibodies appear to contribute to early viral control and T-cell responses are sustained over time, which might contribute to milder presentations during reinfection., Funding: Fundació Lluita contra les Infeccions, IrsiCaixa, and Consorcio Centro de Investigación Biomédica en Red, Instituto de Salud Carlos III, Ministerio de Ciencia, Innovación e Universidades., Competing Interests: Declaration of interests BM reports consultancy personal fees from AELIX Therapeutics and AbbViE and speaker fees from Gilead, Janssen, and ViiV Healthcare. AG is a consultant for Pfizer, outside the submitted work. CB is cofounder, CSO, and shareholder of AELIX Therapeutics and reports consultancy personal fees from Omniscope, Virometix, and Astrivax. AS is a consultant for AstraZeneca Pharmaceuticals, Calyptus Pharmaceuticals, Darwin Health, EmerVax, EUROIMMUN, F Hoffman-La Roche, Fortress Biotech, Gilead Sciences, Gritstone Oncology, Guggenheim Securities, Moderna, Pfizer, RiverVest Venture Partners, and Turnstone Biologics. NI-U reports funding support from the Spanish Ministry of Science and Innovation, HIPRA, Pharma Mar, Amassence, Mynorix, Grifols, and SME. RP reports financial fundings from MSD, ViiV Healthcare, Gilead Sciences, and PharmaMar, and consulting fees or honoraria from Gilead Sciences, Pfizer, AstraZeneca, Roche therapeutics, MSD, GSK ViiV Healthcare, Eli Lilly and Company, PharmaMar, and Atea Pharmaceutics. JM reports consulting fees, honoraria, expert testimony payment, and financial support from ViiV Healthcare, Johnson & Jonhson, Gilead, and MSD. La Jolla Institute has filed for patent protection for various aspects of T-cell epitope and vaccine design work. The authors declare no other competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Yaws, caused by Treponema pallidum ssp. pertenue, remains a significant public health concern in tropical regions of West Africa and the South Pacific, primarily affecting children in remote areas with limited access to hygiene and sanitation. In this study, conducted in three endemic countries of West Africa where yaws remains a significant public health concern (Ghana, Cameroon, and Côte d'Ivoire), we aimed to assess the knowledge, attitudes, and practices related to yaws among community members, community health workers (CHWs), and traditional healers. The study revealed variations in the perception of causes of yaws among community members: the majority or participants in Ghana attributed yaws to germs (60.2%); in Cameroon the most reported form of transmission was contact with or drinking infected water sources (44.6%); and in Côte d'Ivoire both of these answers were also the most prevalent (60.3% germs and 93.% water sources). A substantial proportion of participants in Côte d'Ivoire also associated yaws with witchcraft and divine punishment (44.8%). Only a small proportion of individuals in Ghana and Côte d'Ivoire correctly identified contact with an infected person as a form of transmission (11.9% and 20.7%, respectively) and less than half in Cameroon (42.6%), although more than 98% of all participants reported avoidance behaviours towards yaws infected people due to fear of getting infected. Most participants expressed a preference for seeking care at hospitals (49.2%, 60.6%, 86.2%) or health care professionals including doctors and nurses (58.5%, 41,5% and 17.2%) if they were diagnosed with yaws, although a quarter of participants in Côte d'Ivoire also sought support from traditional healers. The CHWs interviewed were generally well-trained on yaws causes and treatment options, although they often reported low availability of treatment and diagnostic tests for yaws. Our findings underscore the need for community education, awareness campaigns, ongoing CHW training, and improved access to yaws treatment and diagnostic resources. The data also suggest that collaboration with traditional healers, who usually hold a highly esteemed position in the society, such as giving training on yaws causes and transmission or exchanging knowledge on treatment options, could be beneficial in certain regions, particularly in Côte d'Ivoire., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Beiras et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)