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African swine fever virus (ASFV) is a dsDNA virus responsible for a severe, highly contagious, and lethal disease affecting both domestic and wild pigs. ASFV has brought enormous economic loss to a number of countries, and effective vaccine and therapy are still lacking. Therefore, a rapid, sensitive, and field-deployable detection of ASFV is important for disease surveillance and control. Herein, we developed a Cas12a-mediated portable paper assay to rapidly and precisely detect ASFV. We identified a robust set of crRNAs that recognized the highly conserved region of essential ASFV genes. The Cas12a-mediated detection assay showed low tolerance for mismatch mutations, and no cross-reactivity against other common swine pathogens. We further developed a paper-based assay to allow instrument-free detection of ASFV. Specifically, we applied gold nanoparticle-antibody conjugate to engineer homemade strips and combined it with Cas12a-mediated ASFV detection. This portable paper, instrument-free diagnostics, faithfully detected ASFV in swine samples, showing comparable sensitivity to the traditionally instrumentdependent qPCR method. Taking together, we developed a highly sensitive, instant, and economic Cas12a-mediated paper diagnostics of ASFV, with a great application potential for monitoring ASFV in the field.

This study compared the immunogenicity of inactivated SARS-CoV-2 vaccines between people living with HIV (PLWH) and HIV-negative individuals. We recruited 120 PLWH and 53 HIV-negative individuals aged 18–59 years who had received an inactivated SARS-CoV-2 vaccine in two Chinese cities between April and June 2021. Blood samples were tested for immunogenicity of the inactivated SARS-CoV-2 vaccines. The prevalence and severity of adverse events associated with SARS-CoV-2 vaccines were similar between PLWH and HIV-negative individuals. The seropositivity of neutralizing activity against authentic SARS-CoV-2, of the total amount of antibody (total antibody) and of S-IgG were 71.3%, 81.9%, and 92.6%, respectively, among fully vaccinated PLWH. Among all participants, PLWH had lower neutralizing activity, total antibody, S-IgG, and T-cell-specific immune response levels, compared to HIV-negative individuals, after controlling for types of vaccine, time interval between first and second dose, time after receiving the second dose, and sociodemographic factors. PLWH with a longer interval since HIV diagnosis, who received their second dose 15–28 days prior to study commencement, and who had an interval of ≥21 days between first and second dose had higher neutralizing activity levels. The immunogenicity of the inactivated SARS-CoV-2 vaccines was lower among PLWH as compared to HIV-negative individuals. Vaccination guideline specific for PLWH should be developed.

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