Infectious diseases continue to test global health systems, from seasonal viral waves to emerging threats and antimicrobial resistance. Getting new therapies and vaccines to patients depends on Contract Research Organisations (CROs) with proven infectious-disease capability, spanning protocol design, fast start-up, reliable recruitment across multiple regions, robust data and biomarker handling, and clear regulatory navigation.
This blog highlights the top 10 CROs that are well placed to support infectious-disease development in 2025.
When compiling this list, we looked for CROs that publicly document current infectious disease and/or vaccine expertise, show operational scale or specialist depth in relevant indications, and demonstrate credible regulatory, laboratory, or data capabilities. We’ve fact-checked each organisation’s current focus and capabilities and kept the list alphabetical to avoid any implied ranking.
Fortrea runs Phase I–IV infectious-disease and vaccine trials, combining medical, regulatory and operational teams with a broad investigator network. Their materials emphasise experience across geographies and access to patient support networks, including in under-served settings. Fortrea became an independent CRO after Labcorp completed the spin-off in 2023, so sponsors seeking the former Covance/Labcorp clinical development services should now look to Fortrea.
ICON’s infectious-disease group covers vaccines, antibacterials, antivirals and antifungals, and has operated hospital-based respiratory studies, including COVID-19 and severe influenza. They also run antiparasitic programmes. Breadth across pathogens and settings plus global operations make ICON a reliable partner for large multi-country ID studies.
IQVIA’s infectious-disease and vaccines offering leans on technology-enabled trial designs, real-time data delivery and decentralised capabilities, underpinned by its data infrastructure and global reach. For programmes requiring real-world evidence, rapid surveillance or complex data integration, IQVIA’s scale and tooling remain a differentiator.
Medpace supports Phase I–IV infectious-disease and vaccine trials across antivirals, antibacterials, antifungals, vaccines and immunotherapies, with strong physician leadership and integrated labs. Medpace cites contributions in the past seven years to >90% of FDA antibacterial approvals, 66% of antifungal approvals and ~33% of antiviral approvals — a notable regulatory track-record signal for sponsors.
Novotech focuses on biotech sponsors and is well known in Asia-Pacific. Its infectious-disease portfolio spans C. difficile, CMV, HSV, HIV, hepatitis B/C, HPV, influenza, malaria, Japanese encephalitis, respiratory infections and Zika. Capabilities include feasibility, protocol design and adult/paediatric enrolment strategies. Sponsors prioritising APAC feasibility and access to tropical/neglected disease populations often shortlist Novotech.
Parexel integrates epidemiology, public-health and regulatory expertise across Phase I–IV infectious-disease and vaccine programmes, including pathogen surveillance, long-term follow-up and access strategies. They highlight collaborations with government and academic funders (e.g., BARDA, NIH, EMA). Depth in vaccines and public-health-oriented operations makes Parexel a strong choice for prevention trials and multi-stakeholder consortia.
PPD combines global site networks and integrated laboratories (bioanalytical, biomarker, microbiology, molecular genetics) with digital and decentralised approaches. They publicly reference experience across HIV, hepatitis, influenza/RSV, paediatrics and bacterial/fungal/parasitic diseases, and document rapid pandemic responses. Access to Thermo Fisher’s lab ecosystem and experience with emergency-response studies position PPD well for time-critical ID programmes.
Quanticate is a biometrics-focused CRO with more than a decade of infectious-disease work, including Phase III. Teams support HIV, hepatitis, cholera and influenza, and are familiar with endpoints such as quality of life, viral load, CD4 counts and survival analysis. They also analyse genetic variants’ impact on safety and efficacy. For sponsors needing scalable statistics, programming, data management and medical writing with deep domain familiarity in ID endpoints, Quanticate offers specialist strength and flexibility.
Syneos covers bacteriology, virology and mycology across preventive and therapeutic vaccines, anti-infectives and devices. It runs Phase I–IV globally, including first-in-human and immunogenicity studies, and maintains a Vaccine Catalyst Site Network of 30+ dedicated sites to accelerate start-up. The team has experience in Ebola, Zika and COVID-19, plus complex bacterial and fungal infections. Established site partnerships and emergency-response know-how make Syneos a pragmatic option when timelines are tight.
Worldwide is a full-service, mid-size CRO operating across ~60 countries, with recognised performance in Phase II/III delivery. While therapeutic coverage is broad, senior leaders and materials reference infectious-disease experience alongside other areas. Sponsors seeking a mid-size partner with global reach and strong operational marks in later-phase studies may find Worldwide a good fit.
Pathogen Scope and Endpoints
Does the team cover your aetiology (viral, bacterial, fungal, parasitic) and understand relevant endpoints (e.g., viral load, resistance profiles, immunogenicity, survival)?
Recruitment and Site Access
Look for proven access to high-performing sites, including paediatric and special-risk populations, and geographies where your disease is prevalent.
Laboratory and Biomarker Integration
Central lab connectivity, molecular diagnostics and resistance testing speed decisions and improve data quality.
Regulatory and Public Health Experience
Familiarity with expedited pathways and collaboration with agencies/consortia reduces friction in high-stakes programmes.
Data and Trial Design Tools
Real-time data, decentralised methods and platform designs can shorten timelines in rapidly evolving outbreaks.
The infectious-disease trial landscape is continuing to evolve with broader vaccine pipelines, AI-supported study operations and increased use of decentralised and platform trials, which are trends that emerged during the pandemic and continue to shape study design. Sponsors will likely benefit from CROs that combine outbreak-ready operations with rigorous endpoint science and reliable access to diverse populations.
Across prevention and treatment, the CROs above bring distinct strengths from outbreak response and large-scale vaccine work to specialist biometrics and tropical-disease access. By matching your pathogen focus, endpoints and geographies to a partner’s real capabilities, you increase the chances of a smoother path from first patient into decision-grade data.
Quanticate combines deep biometrics expertise with a hands-on approach to streamline your infectious-disease studies. Our teams specialise in statistical programming, clinical data management, medical writing and pharmacovigilance. With 10+ years’ experience across HIV, hepatitis, cholera and influenza — including Phase III — we’re fluent in endpoints such as viral load, CD4 counts, survival and quality-of-life measures, and we analyse genetic variants where they affect safety and efficacy. Ready to accelerate your infectious-disease development? Submit an RFI today.