Viruses

Background: People who inject drugs (PWID) have a higher risk of contracting hepatitis C (HCV) than the general population, but these individuals are often poorly served by traditional healthcare systems. The elimination of HCV as a threat to public health relies on the treatment of this population. Novel care models designed with input from PWID may help to better align care to the needs of PWID. Methods: We designed and implemented a community-based, point-of-care testing program for HCV delivered by a syringe service program, combined with facilitated access to a healthcare provider, care navigation, and financial incentives. We collected participant demographics and drug use patterns, testing and treatment history, and communication preferences. Descriptive analyses include the number of people tested between 15 October 2021 and 1 February 2025, their seropositivity rate, and the number who completed pre-treatment laboratory tests, completed treatment and achieved cure by sustained virologic response (SVR12) by 1 August 2025. Results: The program engaged 464 unique individuals, of whom 98 (21.1%) had a known diagnosis of HCV. Of 389 unique individuals who underwent point of care (POC) HCV antibody (Ab) testing, including 31 with a known prior diagnosis of HCV, 97 (24.9%) had a positive result. Of 439 unique individuals who underwent POC HIV Ab testing, only 1 had a positive result. Of 164 individuals with either a positive POC HCV Ab test or a known HCV diagnosis, 66 completed pre-treatment laboratory tests, identifying 52 viremic participants. Of those, 35 started and completed treatment. Among those who completed treatment, 9 (25.7%) achieved SVR12, 3 (8.6) failed to achieve SVR12, and 23 (65.7%) had outstanding laboratory orders for SVR12 determination. Conclusions: An incentivized, community-based, point-of-care testing program with facilitated linkage to care successfully engaged a high-risk population in HCV and HIV testing and treatment. However, substantial attrition occurred at each step of the care cascade, particularly at SVR12 determination. Additional strategies are needed to optimize retention throughout the entire care cascade.

The convergence of artificial intelligence and synthetic biology is innovating and accelerating the design of novel viral genomes, expanding both therapeutic opportunities and dual-use risk. This review articulates a countermeasure strategy for emerging and engineered viruses leveraging the programmable CRISPR modality. Building on mounting in vitro and in vivo evidence that Cas9 degrades DNA viruses (e.g., Orthopoxviruses, HSV-1, ASFV), while Cas13 targets RNA viral genomes (e.g., Influenza A, Dengue, RSV), both leading to reduced viremia, diminished disease burden, and alleviated symptoms. Here, we outline a rapid-response pipeline to position CRISPR-based countermeasures in translational and pandemic-response frameworks, linking real-time sequencing to AI-assisted gRNA selection and multiplexed cassette design to achieve viral targeting efficacy. To minimize resistance and off-target risk, we emphasize multi-gRNA cocktails, continuous genomic surveillance, and adaptive gRNA rotation. We also propose governance mechanisms, such as pre-cleared gRNA repositories, transparent design logs, standardized off-target/safety screening, and alignment with evolving nucleic-acid-synthesis screening frameworks to enable emergency deployment while preserving security. Furthermore, compressing the time from sequence to treatment and complementary to vaccines and small-molecule antivirals, CRISPR represents a technologically agile and strategically essential capability to combat both natural outbreaks and AI-enabled biothreats. Collectively, programmable CRISPR antivirals represent an auditable, rapidly adaptable foundation for next-generation biodefense preparedness.

The diversity of clinical presentations and outcomes of COVID-19 suggests the influence of host-intrinsic factors that modulate the infectious process. Therefore, a study was conducted with professionals from a hospital in the state of Sergipe, in the Northeast region of Brazil, aiming to identify in this population the effect of rs12329760 and rs2070788, SNPs of the TMPRSS2 enzyme that facilitates the infectious process. Recruitment of the 363 participants followed a non-probabilistic method using a QR code that led to the Informed Consent Form (ICF) and a clinical–epidemiological questionnaire based on self-reported information on the number of positive tests, the presence/absence of symptoms, and severity. Buccal epithelial cells were collected, DNA was extracted using a silica column, and SNP amplification was performed by qPCR. The data were processed using PSPP software, using chi-squared tests for associations in three statistical genetic models (additive, dominant, and recessive). The results showed that, in this population, rs12329760 did not influence any of the outcomes, while rs2070788 was significant in both the additive and recessive models. The action of the G allele is evident in the most severe cases, and it is associated with increased TMPRSS2 expression and potentially increased viral entry efficiency.