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Introduction: Taking into account the difficulty of performing malaria microscopic diagnosis in rural areas, rapid diagnostic tests (RDT) are a good alternative, but it is important to verify their diagnostic performance. Objective: To evaluate the diagnostic performance of the RDTs used in five Colombian departments by comparing them with the microscopic diagnosis and using PCR as the reference standard. Materials and methods: Thick blood film and RDTs were used to diagnose symptomatic individuals; additionally, the filter paper was impregnated with blood for the molecular test. Results: We included 314 samples whose percentage of positivity for malaria was 49% by PCR, 48% by microscopy and 46% by RDT; parasitemia ranged between 180 and 23,800 p/μL of blood. The concordance of the results from the microscopy units and those of the PCR (National Laboratory of Reference) was as follows: Cohen’s kappa coefficient, 0.975 (95% CI: 0.950-0.999); sensitivity, 97% (95% CI 95-100); specificity 100% (95% CI: 100-100), and kappa index of species, 0.958 (IC95%: 0.912-1.00). The concordance between the Pf/Pv RDT (at the microscopy units) and the PCR (National Laboratory of Reference) was as follows: kappa coefficient, 0.878 (95% CI: 0.784-0.973); sensitivity, 94% (95% CI: 87-100); specificity, 95% (95% CI: 90-100), and kappa index of species, 1.0 (95% CI: 1.00-1.00). The concordance between the Pf/Pan RDT versus PCR was: Cohen’s kappa coefficient, 0.920 (95 % CI: 0.865- 0.974); sensitivity, 94% (95% CI: 90-98); specificity, 99% (95% CI 95-100), and kappa index of species, 0.750 (IC95% 0,637-0,863). Conclusion: The results of this study support the use of RDTs in Colombia; however, more training of the personnel is required to accurately differentiate Plasmodium species.

Introduction: To reach the goal of malaria elimination in Ecuador for the year 2020, it is necessary to have a laboratory network with the capacity to perform microscopic diagnosis according to the WHO/PAHO quality standards and to provide the adequate treatment of cases. Objective: To determine the level of competence for parasitological diagnosis of the microscopists from the local public network and the performance of intermediate reference laboratories. Materials and methods: We conducted a cross-sectional study based on the information collected in workshops carried out to appraise the competence for microscopic diagnosis of the local laboratory network (zonal health coordinating offices 1 to 8) using a slide panel to evaluate diagnosis agreement, as well as the diagnostic performance of the intermediate laboratories using an external quality assessment program. The results were compared against the reference standards of the supranational laboratory in Perú. Results: We evaluated the competencies of 191 microscopists in 11 workshops and 153 (80.1%) of them were approved. The medians of the indicators were the following: concordance for parasite detection, 100% (Q1- Q3: 96-100), concordance for species identification, 100% (Q1- Q3: 93-100), and concordances for stage identification, 93.0% (Q1- Q3: 86-95) and parasite counting, 77.0% (Q1- Q3: 71-82). In the external quality assessment, the three intermediate laboratories obtained 100% in parasite detection concordance and 96% for species detection concordance. Conclusions: The results for the primary network and the performance indicators for the intermediate laboratories showed the high-quality standards of the training program implemented in the country.

Introduction: Putumayo is considered an endemic region for malaria transmission, mainly due to Plasmodium vivax. The vectors in this region are Anopheles darlingi , which has been found only in the municipality of Puerto Leguízamo, and An. rangeli and An. oswaldoi s.l. , which were recently incriminated as vectors in Puerto Asís., Objective: The purpose of this study was to determine the role of An. benarrochi B in malaria transmission in Putumayo, given that it is the most abundant species biting humans., Materials and Methods: Collections of immature and adult stages of Anopheles spp. were made between 2006 and 2008 in the municipalities of Puerto Leguízamo and Puerto Asís in Putumayo, and sequences of internal transcribed spacer 2 ( ITS-2 ) of ribosomal DNA and the mitochondrial gene COI were obtained to confirm the morphological determinations. ELISA was carried out for P. vivax and P. falciparum infectivity., Results: A total of 6,238 specimens were identified, distributed in 11 species: An. albitarsis s.l. (1.83%), An. benarrochi B (72.35%), An. braziliensis (0.05%), An. costai (0.06%), An. darlingi (19.37%), An. mattogrossensis (0.08%), An. neomaculipalpus (0.13%), An. oswaldoi s.l. (0.64%), An. punctimacula (0.03%), An. rangeli (5.12%), and An. triannulatus s.l. (0.34%). A total of 5,038 adults were assessed by ELISA and 5 were found positive for P. vivax 210 and VK 247, all belonging to An. benarrochi B., Conclusion: The results suggest that An. benarrochi B plays a role in the transmission of P. vivax in Putumayo due to its high human contact and natural infection with Plasmodium sp.

Introduction: Few studies have described the factors associated with Plasmodium vivax transmission dynamics in endemic regions from Panamá., Objective: Malaria transmission dynamics produced by P. vivax were characterized at the border between Panamá and Costa Rica., Materials and Methods: In the municipality of Barú, an observational, descriptive and cross-sectional study was undertaken to measure the annual parasite index (API), slide positivity index (SPR), and the annual blood examination rate (ABER). The most frequent symptoms and signs in malaria patients were recorded. The anopheline species were identified in the area and the preferred larval habitats, the density of larval populations in the larval habitats and the bites/human/night were characterized., Results: Of a total of 10,401 thick smear blood samples, 83 were positive for P. vivax. Of these, 84% came from rural areas and 79% were from economically active individuals. The median and average ages were 36 and 30 years, respectively, and 58.5% of the malaria cases were male. API was 4.1/1,000 inhabitants; SPR was 0.8% and ABER was 51.9%. Of the diagnosed cases, 54% showed blood parasitemias ranging between 100-2,000 parasites/μl. The majority of the cases were observed in May and June. Two mosquito vector species were identified-- Anopheles albimanus and An. punctimacula., Conclusion: These observations indicate the advisibility of continued entomological studies, strengthening of epidemiological surveillance, consideration of additional risk factors and evaluation of work performance in the border region. This will require coordination with health authorities of both countries to control malaria in this region.

Danger signs are clinical indicators of severity and are useful to predict complications or death. In the malaria patient, clinical or parasitological signs can be easily be recognized during the acute phase of the illness that indicate serious complications. Danger signs include neurological change, abnormal breathing pattern, persistent vomiting and diarrhea, jaundice, bleeding, dark urine, delayed capillary refill, intense pallor, hyperpyrexia, hyperparasitemia and schizontemia. Timely recognition of these signs can lead to a decrease in cases with complications and deaths.

Objective: To evaluate, under laboratory conditions, the sensitivity and specificity of a rapid diagnostic test (OptiMAL), based on immunoreactive strips, to detect Plasmodium vivax infection in febrile patients in Southern Chiapas, Mexico., Material and Methods: The presence of parasites in blood samples of 893 patients was investigated by Giemsa-stained thick blood smear microscopic examination (gold standard). A blood drop from the same sample was smeared on immunoreactive strips to investigate the presence of the parasite pLDH. Discordant results were resolved by PCR amplification of the parasite's 18S SSU rRNA, to discard infection., Results: OptiMAL had an overall sensitivity of 93.3% and its specificity was 99.5%. Its positive and negative predictive values were 96.5% and 98.9%, respectively. Signal intensity in OptiMAL strips correlated well with the parasitemia density in the blood samples (r = 0.601, p = 0.0001)., Conclusion: This rapid test had acceptable sensitivity and specificity to detect P. vivax under laboratory conditions and could be useful for malaria diagnosis in field operations in Mexico.