Clinical characteristics, viral dynamics, and antibody response of monkeypox virus infections among men with and without HIV infection in Guangzhou, China.

Background: Monkeypox virus (MPXV) is spreading globally and nearly half of the infected people were human immunodeficiency virus (HIV) positive. Therefore, an in-depth understanding of the effects of HIV infection on the outcomes of MPXV infection is urgently needed. This study aimed to explore the clinical features, viral dynamics, and antibody response to MPXV infections in men who had sex with men (MSM) with and without HIV co-infection. Design or methods: MPXV-infected patients diagnosed by PCR were recruited in this study and were divided into MPXV and MPXV + HIV groups based on whether they were co-infected with HIV. Clinical data and samples were collected during of the hospital stay and follow up interviews. The symptoms and signs, laboratory examinations, viral shedding in various body fluids or swabs, antibody dynamics were tracked and compared between the two groups. Results: A total of 41 MPXV patients were recruited through June 2023 to September 2023 in Guangzhou. The MPXV group and MPXV + HIV group comprised 20 and 21 MSM, respectively. Patients in the two groups exhibited similar clinical characteristics except for pruritus and eschar, both were significantly fewer in MPXV + HIV group than in MPXV only group. Among the 355 clinical samples collected, MPXV DNA was detected in 100% of scabs, 97.4% of skin swabs, and 92.3% of exudate swabs from lesions, while the positive rate was 87.5% from oropharyngeal swabs, 59% from saliva, 51.3% from anal swabs, 50% from feces, 30.6% from urine samples, 37.5% of semen, and 28.2% from sera. Dynamics analysis revealed that viral DNA was undetectable in most patients 20 days after symptom onset. IgM and IgG antibodies to MPXV were detected in all patients with 3-5 days earlier in the MPXV group than in the MPXV + HIV group. Conclusion: This cohort analysis based on a large outbreak among MSM in Guangzhou indicated no obvious differences in clinical symptoms, viral DNA data, but antibody responses were 3-5 days later in mpox patients with HIV infection.

Applying improved ddPCR to reliable quantification of MPXV in clinical settings.

Monkeypox virus (MPXV) poses a global health threat. Droplet digital PCR (ddPCR) holds potential as an accurate diagnostic tool for clinical microbiology. However, there is limited literature on the applicability of ddPCR in clinical settings. In this study, the clinical features of patients with MPXV during the initial outbreak in China in June 2023 were reviewed, and an optimized ddPCR method with dilution and/or inhibitor removal was developed to enhance MPXV detection efficiency. Eighty-two MPXV samples were tested from nine different clinical specimen types, including feces, urine, pharyngeal swabs, anal swabs, saliva, herpes fluid, crust, and semen, and the viral load of each specimen was quantified. A comparative analysis was performed with qPCR to assess sensitivity and specificity and to investigate the characteristics of MPXV infection by analyzing viral loads in different clinical specimens. Consequently, common pharyngeal and gastrointestinal symptoms were observed in patients with MPXV. The optimized ddPCR method demonstrated relatively high sensitivity for MPXV quantification in the clinical materials, with a limit of detection of 0.1 copies/µL. This was particularly evident in low-concentration samples like whole blood, semen, and urine. The optimized ddPCR demonstrated greater detection accuracy compared with normal ddPCR and qPCR, with an area under the curve (AUC) of 0.939. Except for crust samples, viral loads in the specimens gradually decreased as the disease progressed. Virus levels in feces and anal swabs kept a high detection rate at each stage of post-symptom onset, and feces and anal swabs samples may be suitable for clinical diagnosis and continuous monitoring of MPXV. IMPORTANCE: The ddPCR technique proved to be a sensitive and valuable tool for accurately quantifying MPXV viral loads in various clinical specimen types. The findings provided valuable insights into the necessary pre-treatment protocols for MPXV diagnosis in ddPCR detection and the potentially suitable sample types for collection. Therefore, such results can aid in comprehending the potential characteristics of MPXV infection and the usage of ddPCR in clinical settings.