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The aim of this study was to determine the presence of SARS-CoV-2 on food surfaces and surfaces in public spaces in 3 districts of Lima, Peru. A cross-sectional descriptive study was carried out in three districts of the Lima metropolitan area. Surfaces that were most exposed to users were selected. Samples were swabbed for 4 weeks and transported to the laboratory to determine the presence of the virus. One thousand ninety-five inert surface samples and 960 food surface samples were evaluated for the identification of SARS-CoV-2 by the real time-PCR molecular test, whereby only one sample from an automated teller machine was positive. Most of the inert and food surfaces evaluated did not show the presence of SARS-CoV-2 during the time of sample collection. Despite the negative results, the frequency of disinfection and hygiene measures on high-contact surfaces should be maintained and increased to prevent other highly contagious infectious diseases.

The aim of this study was to determine the presence of SARS-CoV-2 on food surfaces and surfaces in public spaces in 3 districts of Lima, Peru. A cross-sectional descriptive study was carried out in three districts of the Lima metropolitan area. Surfaces that were most exposed to users were selected. Samples were swabbed for 4 weeks and transported to the laboratory to determine the presence of the virus. One thousand ninety-five inert surface samples and 960 food surface samples were evaluated for the identification of SARS-CoV-2 by the real time-PCR molecular test, whereby only one sample from an automated teller machine was positive. Most of the inert and food surfaces evaluated did not show the presence of SARS-CoV-2 during the time of sample collection. Despite the negative results, the frequency of disinfection and hygiene measures on high-contact surfaces should be maintained and increased to prevent other highly contagious infectious diseases.

Objectives: To standardize and validate an in-house RT-LAMP test for the detection of SARS-CoV-2, based on laboratory and field assays using samples from COVID-19 suspected patients., Materials and Methods: An in-house SARS-CoV-2 RT-LAMP molecular test was standardized, establishing the detection limit with Vero cells of isolated Peruvian strains of SARS-CoV-2, and the robustness to various concentrations of primers. The laboratory validation was performed with 384 nasal and pharyngeal swab samples (UFH) obtained between March and July 2020. The field validation was performed with 383 UFH obtained from COVID-19 suspected symptomatic cases. All samples were tested by RT-LAMP and RT-qPCR. The RT-qPCR was considered as the reference standard test. The concordance measures and diagnostic performance were calculated., Results: The detection limit was consistent in cases with Ct <30 in both tests, showing efficiency to detect up to 1000 copies/μL of the target gene. Robustness was evidenced with half of the primer concentrations and 20 μL of final volume. Absence of amplification was identified for other HCoVs. Concordance showed a kappa index of 0.88 (95% CI: 0.83-0.93) and 0.89 (95% CI: 0.84 - 0.94) in laboratory and field settings, respectively. The sensitivity value in the laboratory was 87.4% (95% CI: 80.8 - 92.4) and 88.1% in the field (95% CI: 81.6 - 92.9). The specificity value in both settings was 98.8% (95% CI: 96.4-99.7)., Conclusions: The in-house SARS-CoV-2 RT-LAMP test was successfully validated based on its adequate robustness, no cross-reactions, good concordance, and diagnostic performance compared to RT-qPCR.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is one of the biggest public health issues in the last years. The WHO has reported more than 50,000 confirmed cases and more than 1,000,000 confirmed deaths around the world. Early diagnosis is essential for an appropriate patient care and infection control, so laboratory where molecular tests are held plays a main role. However, laboratory facilities for testing are limited in rural areas. Therefore, it is important to have an effective and practical point-of-care diagnostic system in order to be implemented in developing countries with limited energy access. The objective of this research is to develop an energetically autonomous point-of-care diagnostic system for molecular detection of SARS-CoV-2. This design consists of a retractable system with an area of 15.79 m 2 and 3 well-distributed interior areas to guaranty appropriate sample processing. Our point-of-care diagnostic system can be installed at a fixed place (stationary), and it can also be transported to various strategic places (itinerant). The off-grid photovoltaic system feasibility was evaluated using the PVsyst software, presenting an installed capacity of 2.79 KWp, consisting of 4 monocrystalline photovoltaic modules, a 45 A charge regulator and 4 batteries (6 V, 453 Ah). The results showed a performance ratio of 0.522, with higher losses by the full battery (31.77%). This research determines that the proposed point-of-care diagnostic system meets all requirements to set and operate molecular techniques to diagnose infectious diseases, such as COVID-19, with good laboratory conditions, secure and eco-efficient energy, supporting the health scheme to prevent and control the spread of the virus., Competing Interests: Conflict of interestNot applicable., (© The Author(s), under exclusive licence to Springer Nature B.V. part of Springer Nature 2021.)

Objective: Describe the clinical and epidemiological characteristics and resistance profile of cases of extensively drug-resistant tuberculosis (XDR-TB) diagnosed in Peru from 2013 to 2015., Methods: This descriptive study included patients who met the definition of XDR-TB and were reported to the national epidemiological surveillance system of Peru's Ministry of Health. It used a descriptive analysis and, to identify spatial distribution, a heat map based on kernel density estimation., Results: It was estimated that XDR-TB cases diagnosed as new represented 7.3% of all multidrug-resistant tuberculosis (MDR-TB) cases reported during the study period; 74% of patients were aged 15 to 44 years old; and the male-female ratio was 1.7. Half of the country's departments reported at least one case of XDR-TB, and 42% of new cases had no history of resistance or previous treatment. In the other half of the departments, the majority had previous MDR and pre-XDR resistance. Among the cases, 57.7% presented resistance to 5 and 7 first- and second-line drugs and 41.6% presented resistance to 8 and 10 drugs., Conclusions: This study offers important details of the epidemiological profile of XDR-TB in Peru, where there has been an increase in cases of primary XDR-TB; that is, cases with no prior history of disease. Furthermore, this form of tuberculosis has spread to a greater number of departments in the country.

A Reverse Transcription Loop-mediated Isothermal Amplification (RT-LAMP) method was developed to detect Zika. The primers were designed based on the NS5 region of 64 complete genomes. Lyophilized LAMP reagent was used. Initially, seven different arboviruses were tested and only Zika samples tested positive. Additionally, serial dilutions of one of Zika's RNA were compared using RT-LAMP and qRT-PCR, demonstrating that RT-LAMP is 1,000 times more sensitive. We also evaluated 300 serum samples with RT-LAMP comparing the results with standard qRT-PCR methods, and we obtained a 99.3% sensitivity, 100% specificity, 100% positive predictive value, and 99.3% negative predictive value. In conclusion, this method provides a low-cost, high-performance, viable, and reliable alternative for the rapid diagnosis of Zika in primary health-care facilities.

Objectives.: To describe the phenotypic and genotypic patterns of the antimicrobial resistance of Salmonella Infantis in Peru., Materials and Methods.: Two hundred and ninety-seven strains of Salmonella sp. submitted to the National Institute of Health (INS, in Spanish) during 2014-2016 were analyzed. The strains were phenotypically characterized by microbiological, serological, and antimicrobial susceptibility tests. Based on antimicrobial resistance patterns, 46 strains were selected and genetically characterized by next generation sequencing., Results.: 193/297 (65%) strains of Salmonella Infantis were identified, of which 143 (74.1%) were multidrug-resistant producers of extended spectrum beta-lactamases (ESBL). The genomic sequencing evidenced a new profile for Salmonella Infantis; additionally, it identified the presence of 15 different genetic determinants of antimicrobial resistance coded in bacterial chromosome and five coded in a megaplasmid. The phenotypic and genotypic resistance patterns matched, with the exception of ceftazidime. Moreover, the 46 strains presented resistance and/or decreased sensitivity to quinolones., Conclusions.: Salmonella Infantis has become one of the sero-varieties most frequently referred to the INS, which includes ESBLproducing multidrug-resistant strains with resistance to quinolones. Finally, the relevance of next generation sequencing is reasserted in the characterization of new variants of pathogens that are important for public health, and their potential use in antimicrobial resistance surveillance systems.

Vibrio parahaemolyticus is a marine microorganism that can cause seafood-borne gastroenteritis in humans. The infection can be spread and has become a pandemic through the international trade of contaminated seafood. Strains carrying the tdh gene encoding the thermostable direct hemolysin (TDH) and/or the trh gene encoding the TDH-related hemolysin (TRH) are considered to be pathogenic with the former gene being the most frequently found in clinical strains. However, their distribution frequency in environmental isolates is below 1%. Thus, very sensitive methods are required for detection and quantitation of tdh (+) strains in seafood. We previously reported a method to detect and quantify tdh (+) V. parahaemolyticus in seafood. This method consists of three components: the most-probable-number (MPN), the immunomagnetic separation (IMS) targeting all established K antigens, and the loop-mediated isothermal amplification (LAMP) targeting the tdh gene. However, this method faces regional issues in tropical zones of the world. Technicians have difficulties in securing dependable reagents in high-temperature climates where we found MPN underestimation in samples having tdh (+) strains as well as other microorganisms present at high concentrations. In the present study, we solved the underestimation problem associated with the salt polymyxin broth enrichment for the MPN component and with the immunomagnetic bead-target association for the IMS component. We also improved the supply and maintenance of the dependable reagents by introducing a dried reagent system to the LAMP component. The modified method is specific, sensitive, quick and easy and applicable regardless of the concentrations of tdh (+) V. parahaemolyticus. Therefore, we conclude this modified method is useful in world tropical, sub-tropical, and temperate zones.