Jin-Xin Lai

Chikungunya fever (CHIKF), an acute viral illness transmitted by mosquitoes and first discovered in Tanzania in 1952, has shown intermittent spread in China, with increasing local outbreaks. By July 2025, Guangdong Province, currently the outbreak's center, had reported 4,824 local cases, including nearly 3,000 new infections in just one week. This rapid surge creates an urgent need for advanced diagnostic technologies. Such tools are critical to support containment efforts on the front lines. We propose a solution for the rapid simultaneous detection of dengue (DENV), chikungunya (CHIKV), and Zika virus (ZIKV) infections to enhance early epidemic prevention and control capabilities. This approach involves developing customized testing protocols for border checkpoints and primary healthcare facilities. Traditional diagnostic methods for CHIKV and DENV often lack sensitivity/specificity in coinfection cases. Since CHIKV, DENV, and ZIKV share similar transmission patterns and symptoms, simultaneous monitoring is crucial. This protocol presents a triplex qPCR method using TaqMan probes to detect these arboviruses in a single tube within 90 min. Compared to viral culture and serological tests, this method improves efficiency by identifying active infections and coinfections with high specificity while simplifying workflow and eliminating specialized equipment requirements. Validation with clinical and External Quality Assessment (EQA) samples confirmed 100% concordance with gold-standard singleplex assays. This method serves as an effective tool for monitoring febrile illnesses in endemic regions, particularly in resource-limited settings where rapid outbreak containment is critical.

Chikungunya fever (CHIKF), an acute viral illness transmitted by mosquitoes and first discovered in Tanzania in 1952, has shown intermittent spread in China, with increasing local outbreaks. By July 2025, Guangdong Province, currently the outbreak's center, had reported 4,824 local cases, including nearly 3,000 new infections in just one week. This rapid surge creates an urgent need for advanced diagnostic technologies. Such tools are critical to support containment efforts on the front lines. We propose a solution for the rapid simultaneous detection of dengue (DENV), chikungunya (CHIKV), and Zika virus (ZIKV) infections to enhance early epidemic prevention and control capabilities. This approach involves developing customized testing protocols for border checkpoints and primary healthcare facilities. Traditional diagnostic methods for CHIKV and DENV often lack sensitivity/specificity in coinfection cases. Since CHIKV, DENV, and ZIKV share similar transmission patterns and symptoms, simultaneous monitoring is crucial. This protocol presents a triplex qPCR method using TaqMan probes to detect these arboviruses in a single tube within 90 min. Compared to viral culture and serological tests, this method improves efficiency by identifying active infections and coinfections with high specificity while simplifying workflow and eliminating specialized equipment requirements. Validation with clinical and External Quality Assessment (EQA) samples confirmed 100% concordance with gold-standard singleplex assays. This method serves as an effective tool for monitoring febrile illnesses in endemic regions, particularly in resource-limited settings where rapid outbreak containment is critical.

Staphylococcus aureus (S.aureus) is a common Gram-positive human pathogen that causes community-acquired and nosocomial infections, with diverse clinical manifestations ranging from local superficial lesions and food poisoning to fatal systemic infections. The discovery of antibiotics significantly reduced the mortality rate, but the problem of drug resistance has since become increasingly prominent. Since the first identification of MRSA in 1960, this strain has emerged as a global public health threat. MRSA is a major pathogen of nosocomial infections, capable of causing various severe diseases such as endocarditis, chronic osteomyelitis, pneumonia, pyogenic arthritis, and bacteremia. Therefore, rapid and accurate detection of S. aureus and its drug resistance is crucial for guiding clinical treatment. Current routine detection methods for S.aureus and MRSA have significant limitations. The traditional bacterial culture method, serving as the "gold standard" for decades, can provide definitive species identification and drug sensitivity results, but the process is time-consuming, taking 48 to 72 h. Furthermore, this method is susceptible to contamination and relies on specialized laboratory facilities and skilled technicians. Serological testing achieves non-invasive diagnosis by detecting S.aureus antibodies in patient serum, but it cannot distinguish between active infections and past infections, nor can it identify drug-resistant strains (such as MRSA). This study focuses on developing a novel multiplex real-time fluorescence PCR detection method to overcome the above-mentioned limitations. This method designs specific primers and TaqMan fluorescent probes targeting the species-specific nuc gene of S.aureus and the mecA gene mediating methicillin resistance, enabling simultaneous amplification and detection of S.aureus and MRSA in a single reaction system. This technology greatly reduces the detection time, providing a rapid, accurate, and cost-effective solution for S.aureus and MRSA detection. This innovative approach greatly improves clinical diagnostic efficiency and facilitates the early implementation of targeted antibiotic therapy, making important contributions to controlling drug-resistant bacterial infections.

Staphylococcus aureus (S.aureus) is a common Gram-positive human pathogen that causes community-acquired and nosocomial infections, with diverse clinical manifestations ranging from local superficial lesions and food poisoning to fatal systemic infections. The discovery of antibiotics significantly reduced the mortality rate, but the problem of drug resistance has since become increasingly prominent. Since the first identification of MRSA in 1960, this strain has emerged as a global public health threat. MRSA is a major pathogen of nosocomial infections, capable of causing various severe diseases such as endocarditis, chronic osteomyelitis, pneumonia, pyogenic arthritis, and bacteremia. Therefore, rapid and accurate detection of S. aureus and its drug resistance is crucial for guiding clinical treatment. Current routine detection methods for S.aureus and MRSA have significant limitations. The traditional bacterial culture method, serving as the "gold standard" for decades, can provide definitive species identification and drug sensitivity results, but the process is time-consuming, taking 48 to 72 h. Furthermore, this method is susceptible to contamination and relies on specialized laboratory facilities and skilled technicians. Serological testing achieves non-invasive diagnosis by detecting S.aureus antibodies in patient serum, but it cannot distinguish between active infections and past infections, nor can it identify drug-resistant strains (such as MRSA). This study focuses on developing a novel multiplex real-time fluorescence PCR detection method to overcome the above-mentioned limitations. This method designs specific primers and TaqMan fluorescent probes targeting the species-specific nuc gene of S.aureus and the mecA gene mediating methicillin resistance, enabling simultaneous amplification and detection of S.aureus and MRSA in a single reaction system. This technology greatly reduces the detection time, providing a rapid, accurate, and cost-effective solution for S.aureus and MRSA detection. This innovative approach greatly improves clinical diagnostic efficiency and facilitates the early implementation of targeted antibiotic therapy, making important contributions to controlling drug-resistant bacterial infections.

Helicobacter pylori can be parasitic in gastric mucosa, which can cause a series of gastrointestinal diseases after infection and is closely related to gastritis, gastric ulcer, and gastric cancer. The high prevalence of H. pylori infection in regions with poor medical infrastructure and inadequate sanitation areas remains a significant public health concern. Consequently, the development of rapid, simple, and cost-effective screening methods for H. pylori detection in resource-limited settings is of paramount importance. In this study, we conducted a community-based screening in Shitan Village, Guangdong Province, a remote and underdeveloped area characterized by a permanent population of approximately 300 residents with generally low educational attainment. We employed a double antibody sandwich assay for the detection of H. pylori fecal antigen, a method chosen for its potential applicability in low-resource settings. A total of 261 participants from the village were enrolled, and their fecal samples were analyzed using this technique. For comparative validation, the same samples were subjected to quantitative polymerase chain reaction (qPCR) analysis. Compared with qPCR results, the sensitivity and specificity of the detection of H. pylori antigen in feces were 60.24% and 80.08%. The results demonstrated a strong agreement between the fecal antigen detection method and qPCR (Kappa = 0.630). This study systematically elucidated the principles, procedures, methodologies, and clinical applications of fecal antigen detection for H. pylori infection, aiming to explore latex-based double antibody sandwich technology and establish novel strategies and practical guidelines for its auxiliary diagnosis.

Helicobacter pylori can be parasitic in gastric mucosa, which can cause a series of gastrointestinal diseases after infection and is closely related to gastritis, gastric ulcer, and gastric cancer. The high prevalence of H. pylori infection in regions with poor medical infrastructure and inadequate sanitation areas remains a significant public health concern. Consequently, the development of rapid, simple, and cost-effective screening methods for H. pylori detection in resource-limited settings is of paramount importance. In this study, we conducted a community-based screening in Shitan Village, Guangdong Province, a remote and underdeveloped area characterized by a permanent population of approximately 300 residents with generally low educational attainment. We employed a double antibody sandwich assay for the detection of H. pylori fecal antigen, a method chosen for its potential applicability in low-resource settings. A total of 261 participants from the village were enrolled, and their fecal samples were analyzed using this technique. For comparative validation, the same samples were subjected to quantitative polymerase chain reaction (qPCR) analysis. Compared with qPCR results, the sensitivity and specificity of the detection of H. pylori antigen in feces were 60.24% and 80.08%. The results demonstrated a strong agreement between the fecal antigen detection method and qPCR (Kappa = 0.630). This study systematically elucidated the principles, procedures, methodologies, and clinical applications of fecal antigen detection for H. pylori infection, aiming to explore latex-based double antibody sandwich technology and establish novel strategies and practical guidelines for its auxiliary diagnosis.

Helicobacter pylori (H. pylori) is widely prevalent worldwide, with approximately 50% of the global population having a history of H. pylori infection. In China, the infection rate ranges from 40% to 70%. H. pylori is primarily associated with gastrointestinal diseases such as chronic gastritis, gastric ulcers, and duodenal ulcers. Currently, the clinical treatment for H. pylori infection involves either triple or quadruple therapy. However, the extensive use of antibiotics has led to the development of antibiotic resistance in H. pylori. Therefore, detecting both H. pylori and its antibiotic resistance is crucial for guiding clinical treatment. Diagnostic methods for H. pylori include urea breath test (UBT), antigen test, serological antibody test, endoscopy, rapid urease test (RUT), and bacterial culture. While the first three methods are non-invasive, they do not allow for bacterial recovery and, thus, cannot be used for resistance testing. The latter three methods are invasive, expensive, require high technical expertise, and may cause harm to patients. Therefore, a non-invasive, rapid method for simultaneous detection of H. pylori infection and antibiotic resistance is of utmost clinical importance for the effective eradication of H. pylori. This paper aims to introduce a specific protocol that combines quantitative polymerase chain reaction (qPCR) with TaqMan fluorescent probe technology to rapidly detect H. pylori infection and antibiotic resistance. This method provides a convenient, rapid, and non-invasive way to diagnose H. pylori infection and resistance, unlike traditional bacterial culture and other techniques. qPCR is used to identify the infection and detect mutations in the 23S rRNA and gyrA genes, which are linked to resistance to clarithromycin and quinolones, respectively. Compared to conventional culture techniques, this approach offers a non-invasive, cost-effective, and time-efficient method for detecting Helicobacter pylori infection and determining its antibiotic resistance.

Helicobacter pylori (H. pylori) is widely prevalent worldwide, with approximately 50% of the global population having a history of H. pylori infection. In China, the infection rate ranges from 40% to 70%. H. pylori is primarily associated with gastrointestinal diseases such as chronic gastritis, gastric ulcers, and duodenal ulcers. Currently, the clinical treatment for H. pylori infection involves either triple or quadruple therapy. However, the extensive use of antibiotics has led to the development of antibiotic resistance in H. pylori. Therefore, detecting both H. pylori and its antibiotic resistance is crucial for guiding clinical treatment. Diagnostic methods for H. pylori include urea breath test (UBT), antigen test, serological antibody test, endoscopy, rapid urease test (RUT), and bacterial culture. While the first three methods are non-invasive, they do not allow for bacterial recovery and, thus, cannot be used for resistance testing. The latter three methods are invasive, expensive, require high technical expertise, and may cause harm to patients. Therefore, a non-invasive, rapid method for simultaneous detection of H. pylori infection and antibiotic resistance is of utmost clinical importance for the effective eradication of H. pylori. This paper aims to introduce a specific protocol that combines quantitative polymerase chain reaction (qPCR) with TaqMan fluorescent probe technology to rapidly detect H. pylori infection and antibiotic resistance. This method provides a convenient, rapid, and non-invasive way to diagnose H. pylori infection and resistance, unlike traditional bacterial culture and other techniques. qPCR is used to identify the infection and detect mutations in the 23S rRNA and gyrA genes, which are linked to resistance to clarithromycin and quinolones, respectively. Compared to conventional culture techniques, this approach offers a non-invasive, cost-effective, and time-efficient method for detecting Helicobacter pylori infection and determining its antibiotic resistance.