Introduction

The management of infectious samples has long been a critical component of both clinical and research laboratory settings. It ensures not only the safety of personnel but also the accuracy of diagnostic results. The rise of emerging infectious diseases such as COVID-19, Ebola, and various zoonotic pathogens has further underscored the importance of stringent biosafety and decontamination procedures in handling potentially infectious specimens. Ensuring proper handling involves multiple layers of safety measures, including personal protective equipment (PPE), appropriate sample collection techniques, and validated decontamination protocols to mitigate the risk of pathogen transmission.

Laboratories dealing with infectious samples are regulated by international and local guidelines such as the World Health Organization's Laboratory Biosafety Manual and the Centers for Disease Control and Prevention's Biosafety in Microbiological and Biomedical Laboratories. These guidelines stress the importance of categorizing pathogens based on their biosafety levels and implementing appropriate containment measures. For instance, handling Mycobacterium tuberculosis, classified as a Biosafety Level 3 (BSL-3) agent, requires specialized facilities equipped with controlled airflows and HEPA filtration systems (1).

Decontamination, a cornerstone of laboratory safety, involves various chemical and physical methods to eliminate or inactivate pathogens. Disinfectants such as sodium hypochlorite and ethanol are widely used in combination with heat sterilization to decontaminate surfaces and equipment effectively. However, the efficacy of these methods can be influenced by factors such as the nature of the pathogen, environmental conditions, and the organic load present on surfaces (2). Emerging technologies like vaporized hydrogen peroxide and ultraviolet (UV-C) light offer promising enhancements to traditional decontamination strategies, providing broader spectrum efficacy and reducing chemical residues (3). In addition to technical measures, the human factor plays a significant role in biosafety. Proper training in the use of PPE, waste disposal, and response to accidental exposures is imperative. Studies have shown that inadequate training or noncompliance with established protocols significantly increases the risk of laboratory-acquired infections (4). Therefore, regular audits and refresher training sessions are essential to maintain a culture of safety.

Despite advancements in safety measures, challenges persist. For example, low-resource settings often lack the infrastructure necessary to implement advanced biosafety measures, leading to higher exposure risks. Furthermore, the increasing globalization of research and diagnostic activities necessitates standardized approaches to ensure consistent safety practices across laboratories worldwide. Addressing these challenges requires an integrated approach involving policy updates, technological innovation, and capacity building. The continuous evolution of pathogens and the growing complexity of diagnostic technologies demand ongoing updates to safety and decontamination protocols. This review aims to discuss the safety and decontamination procedures for infectious sample handling.

Review

Effective handling of infectious samples is essential for the safety of both laboratory personnel and the broader public. One key consideration in this process is ensuring thorough decontamination of surfaces and equipment that may come into contact with infectious agents. Recent studies have highlighted the importance of understanding the specific risks associated with different pathogens and tailoring decontamination procedures accordingly. The cleaning and disinfection of environmental surfaces, such as door handles and hospital beds, are critical measures in reducing the transmission of hospital-acquired infections. These measures should include a combination of surface cleaning and high-level disinfection, particularly in high-risk areas (5).

In addition to surface disinfection, the proper handling and transportation of samples are crucial in minimizing the risk of contamination. Guidelines emphasize the need for secure packaging and correct labelling of samples to ensure that they are safely transported to the laboratory for analysis. Studies have shown that inadequate training and improper handling of infectious materials can lead to exposure incidents (6). This underscores the importance of regular safety audits, training, and the use of appropriate PPE for all personnel involved in handling infectious samples. Establishing a culture of safety within laboratories is essential to ensure compliance with these rigorous protocols and safeguard against potential outbreaks.

Innovative Decontamination Technologies and Their Efficacy

The exploration of innovative decontamination technologies has ushered in a new era of safety protocols for handling infectious materials, reflecting advancements in science and engineering. Cold atmospheric plasma is one such groundbreaking approach. It generates a partially ionized gas containing reactive species capable of disrupting microbial cell walls, leading to effective sterilization. Studies have demonstrated its utility not only in microbial decontamination but also in reducing mycotoxin contamination on food surfaces. Its non-thermal nature ensures the integrity of heat-sensitive materials, broadening its applicability across various sectors (7). Advancements in photocatalytic processes have also garnered attention. Titanium dioxide (TiO₂)-based photocatalysts, activated under ultraviolet (UV) or visible light, decompose organic contaminants, including pathogenic microorganisms. Recent innovations have incorporated black TiO₂, enabling broader light absorption and greater efficacy under ambient conditions. This enhancement has made it viable for applications in water treatment systems, addressing contamination in remote or resource-constrained areas. Its environmental sustainability and low energy requirements are significant benefits, particularly in the face of increasing global water scarcity (8).

Ultraviolet germicidal irradiation remains a cornerstone in surface and air decontamination. However, integrating narrow-spectrum UV-C light with nanomaterial coatings has amplified its bactericidal effects. The incorporation of silver nanoparticles into these systems has shown synergistic effects, improving microbial eradication rates. These combined technologies have shown promise in mitigating the transmission of airborne pathogens, especially in high-traffic healthcare settings (9). Lastly, deep eutectic solvents, a class of environmentally benign liquid compounds, have shown potential in decontamination applications. Unlike conventional chemical disinfectants, deep eutectic solvents can selectively disrupt lipid membranes of enveloped viruses while preserving non-porous surfaces. Their tunable properties allow customization for specific pathogens, offering a tailored approach to biosafety. Their use in medical device sterilization and laboratory environments could significantly reduce dependency on toxic chemicals, advancing both safety and environmental objectives (10).

Risk Assessment and Mitigation Strategies in Infectious Sample Handling

Effective risk assessment in infectious sample handling hinges on a thorough understanding of the pathogenic characteristics and environmental interactions of infectious agents. Quantitative microbial risk assessment (QMRA) models provide a structured framework for evaluating microbial transmission risks. These models consider exposure routes, dose-response relationships, and mitigation strategies, offering insights into the reduction of infection risks in laboratory settings. Recent advancements in QMRA emphasize the integration of molecular data to enhance the precision of exposure assessments, as demonstrated in foodborne pathogens like Campylobacter in broiler meat (11). The role of environmental sampling and monitoring in risk mitigation cannot be understated. High-risk zones such as laboratories and healthcare facilities rely on targeted surface and air sampling techniques to identify contamination hotspots. Advanced environmental diagnostic tools, including next-generation sequencing, have improved the detection and tracking of resistant pathogens. A study on gull populations near urban areas highlighted the potential of such techniques to monitor and mitigate the spread of antibiotic-resistant bacteria, demonstrating the broader applicability of these tools beyond clinical environments (12).

Another critical component in reducing risk is personnel training in biosafety practices. Evidence shows that comprehensive training significantly lowers exposure incidents during sample processing and handling. In a case study on zoonotic interfaces, researchers found that well-trained personnel could prevent cross-species pathogen transmission during the handling of influenza and Lassa fever samples. Ensuring consistent education and real-time feedback mechanisms plays a vital role in maintaining a high standard of safety (13). Additionally, advances in sample transportation systems have minimized the risks associated with inter-laboratory transfer of infectious materials. Temperature-controlled, vacuum-sealed containers equipped with bioindicator alarms are now standard in many facilities, significantly reducing contamination risks. A study in sub-Saharan Africa underscored the effectiveness of using these advanced containers for the safe transportation of blood samples in malaria research, highlighting their potential in resource-limited settings (14).

Regulatory Standards and Compliance in Biosafety Protocols

The increasing complexity of handling infectious agents in laboratories has prompted an urgent need for more comprehensive biosafety regulations and strict compliance protocols. Modern biosafety standards are not merely procedural checklists but dynamic frameworks designed to adapt to evolving risks. For laboratories operating at BSL-3 and BSL-4, adherence to regulatory protocols is paramount, given the potentially catastrophic consequences of non-compliance. The integration of artificial intelligence-based monitoring systems within BSL-3 facilities exemplifies how technology is reshaping compliance enforcement. These systems leverage machine learning algorithms to continuously assess workflows, identify anomalies, and provide actionable insights to preempt risks. A recent study highlighted the success of such systems in reducing procedural deviations, significantly improving safety outcomes (15).

Harmonization of biosafety guidelines across regions is another critical aspect of mitigating risk. The disparities in biosafety practices often stem from varying interpretations of global standards. Efforts such as those by the European Biosafety Association to standardize viral inactivation protocols have proven invaluable in addressing this issue. These protocols ensure that laboratories handling viral pathogens, especially those involved in virus isolation and culture, follow consistent and scientifically validated practices. Such initiatives also underscore the importance of fostering collaboration between laboratories worldwide, ensuring that best practices are shared and implemented universally (16).

The physical infrastructure of biosafety-compliant laboratories is an essential element that supports operational standards. In recent years, modular biocontainment units have emerged as innovative solutions to the logistical challenges of expanding laboratory capacity. These units are equipped with advanced features such as integrated sterilization systems, HEPA filtration, and containment barriers. Their modular nature allows for scalability, making them particularly suited for rapid deployment in outbreak scenarios or in resource-limited settings. Studies have shown that facilities equipped with such units not only meet but often exceed international biosafety standards, providing a flexible yet robust solution to global biosafety challenges (17). Education and training are pivotal to fostering a culture of safety and ensuring compliance with biosafety protocols. While infrastructure and technological advancements form the backbone of biosafety, they must be complemented by comprehensive training programs tailored to the needs of laboratory personnel. Regular audits and hands-on workshops can bridge gaps in knowledge and reinforce the importance of strict adherence to guidelines. Research into compliance behavior has shown that laboratories that prioritize ongoing education for their staff experience significantly fewer incidents of biosafety violations. Moreover, the inclusion of simulation-based training, which mimics real-world scenarios, has proven effective in preparing personnel for unexpected contingencies (18).

Another dimension of compliance involves the systematic evaluation of laboratory practices through regulatory audits. These audits, conducted by national and international agencies, play a critical role in identifying vulnerabilities within existing protocols. For instance, pharmaceutical microbiology laboratories that underwent frequent inspections were observed to have higher compliance rates compared to those with less oversight. Regulatory audits also drive innovation by pushing laboratories to adopt newer, safer technologies and methodologies. Beyond identifying shortcomings, audits serve as platforms for knowledge exchange, enabling laboratories to learn from peers and incorporate the best global practices. Compliance in biosafety is also deeply intertwined with ethical considerations (19). Laboratories handling genetically modified organisms or emerging pathogens face the dual challenge of ensuring scientific integrity and addressing public concerns about safety. Transparency in operations, coupled with robust community engagement, has been identified as a key strategy for building public trust. Initiatives aimed at enhancing the traceability of biological materials and ensuring accountability in research are critical to sustaining ethical standards in biosafety.

As the global research ecosystem becomes more interconnected, the role of international regulatory bodies in enforcing compliance cannot be overstated. Organizations such as the World Health Organization and the Centers for Disease Control and Prevention have been instrumental in developing and disseminating biosafety frameworks. Their guidelines provide a benchmark for national policies, ensuring consistency and reliability across diverse operational contexts. However, the implementation of these guidelines often requires customization to address local challenges, such as resource constraints or cultural differences.

Conclusion

Robust biosafety protocols and regulatory standards are the cornerstone of safe infectious sample handling, minimizing risks to both personnel and the environment. Advancements in technology, standardized global practices, and comprehensive training programs have significantly enhanced compliance and operational safety. However, sustained commitment to education, ethical transparency, and adaptive frameworks is crucial to addressing emerging biosafety challenges. By fostering collaboration and innovation, laboratories can ensure preparedness for future biological threats.

Disclosure

Conflict of interest

There is no conflict of interest.

Funding

No funding.

Ethical consideration

Non applicable.

Data availability

Data that support the findings of this study are embedded within the manuscript.

Author contribution

All authors contributed to conceptualizing, data drafting, collection and final writing of the manuscript.