scholarly journals AUTOMATED HEMATOLOGY ANALYZERS IN DIAGNOSIS OF PLASMODIUM VIVAX MALARIA: AN ADJUNCT TO CONVENTIONAL MICROSCOPY.

2014 ◽  
Vol 6 (1) ◽  
pp. e2014034
Author(s):  
Kolakkadan Mubeen Hasaf ◽  
Wilfred Clement Devadoss ◽  
Rau Rangan Aarathi ◽  
Monnappa Gitanjali ◽  
Shetty Prasanna ◽  
...  
Keyword(s):  
Positive Predictive Value ◽  
Predictive Value ◽  
Vivax Malaria ◽  
High Sensitivity ◽  
Rapid Diagnosis ◽  
Parasitic Diseases ◽  
Presumptive Diagnosis ◽  
Plasmodium Vivax Malaria ◽  
Conventional Microscopy ◽  
Hematology Analyzers

Malaria is one of the most pervasive parasitic diseases ever known to mankind affecting nearly 300 million people every year. The need for rapid diagnosis of malaria in tropical and subtropical malaria endemic areas is on the rise. In this study we evaluated the usefulness of hematology autoanalyzers, Sysmex XE-2100 & XT-2000i in the presumptive diagnosis of malaria. Our study shows that abnormalities in WBC/BASO scattergram when combined with presence of thrombocytopenia had a high sensitivity and positive predictive value in the presumptive diagnosis of malaria.

scholarly journals Evaluating Specivity, Sensitivity, Positive and Negative Predictive Values of CA125 for Diagnosing Ovarian Cancer

2021 ◽  
Vol 24 (2) ◽  
pp. 196-203
Author(s):  
Elahe Fini ◽  
◽  
Neda Nasirian ◽  
Bahram Hosein Beigy ◽  
◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Positive Predictive Value ◽  
Tumor Marker ◽  
Negative Predictive Value ◽  
Predictive Value ◽  
Screening Test ◽  
High Sensitivity ◽  
Medical Community ◽  
Cross Sectional ◽  
Predictive Values

Background and Aim: Ovarian cancer is among the most common cancers in women worldwide. CA125 is the most frequent biomarker used in the screening for ovarian cancer. CA125 has no high sensitivity and specificity as a screening test in the medical community; however, because of being simple and noninvasive, it is almost always requested for evaluation and ruling out cancer. It plays an important role in the treatment and post-treatment process, the prediction of prognosis, and the relapse of the disease. The present study aimed to determine the relationship between a high level of CA125 tumor marker and ovarian cancer by detecting spesivity, sensivity, positive and negative predictive values. Methods & Materials: In this cross-sectional study, all cases undergoing CA125 test in Velayat Hospital in 2017-1028 were evaluated for having ovarian cancer. In addition, the CA125 level was compared between healthy individuals and patients with ovarian cancer. Finally, the obtained data were analyzed using SPSS. Ethical Considerations: The present study was approved by the Qazvin University of Medical Sciences (Ethics Code: IR.QUMS.REC.1396.316). Results: In this study, 35.3% of the study participants received a definite diagnosis of ovarian cancer. Generally, CA125 values were negative in 41.8% and positive in.58.2% of the study subjects. The sensitivity of the test was measured as 80.1%, the specivity as 53.6%, the positive predictive value equaled 48.4%, and the negative predictive value was measured as 83%. There was a significant relationship between age and the presence of ovarian cancer, and serum CA125 levels. Conclusion: The present study suggested that age and the serum level of CA125 were statistically significant. Finally, CA125 levels were significantly related to ovarian cancer. It provided moderate specivity and specivity as well as low positive predictive value and high negative predictive value as a tumor marker; it is valuable for ruling out of tumor but not appropriate as a screening test.

Abstract 3426: Approximate Volume Using "XYZ/2" Is Equivalent to Planimetric Volume Mismatch Evaluation

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Marie Luby ◽  
Jennifer Hong ◽  
José G Merino ◽  
John K Lynch ◽  
Amie W Hsia ◽  
...  
Keyword(s):  
Positive Predictive Value ◽  
Predictive Value ◽  
Gold Standard ◽  
Correlation Coefficients ◽  
High Sensitivity ◽  
Evaluation Methods ◽  
Slice Thickness ◽  
Linear Measurements ◽  
Visual Evaluation ◽  
Volume Measurements

Objectives: In the clinical setting, the extent of mismatch on MRI is frequently assessed with an approximate “XYZ/2” method but the agreement with the “gold standard” planimetric volume and the “visual evaluation” methods are not known. In a published study, we established that the visual evaluation and planimetric methods are equivalent as far as mismatch classification. The objectives of this study were to quantify the agreement of the approximate method with the “gold standard” and “visual evaluation” methods and to compare the mismatch classification results. Methods: Patients were selected from the Lesion Evolution of Stroke and Ischemia On Neuroimaging (LESION) database if they: had an acute ischemic stroke, were treated with intravenous rt-PA only, and had a pre-treatment MRI with evaluable maps including trace or isotropic b1000 DWI and MTT images. A trained rater viewed the images on the PACS, placed the two perpendicular linear measurements, “X” and “Y”, on the slices with the largest DWI and MTT lesion areas, and then used a “XYZ/2” formula where “Z” was the product of the slice thickness and the total number of slices containing the lesion. A separate expert rater measured the planimetric volumes on a slice-by-slice basis with a semiautomated segmentation tool followed by manual editing. Expert readers evaluated the MRI scans for the presence of qualitative mismatch. The expert readers were not the trained reader that performed the approximate volume measurements. Quantitative mismatch was considered present if MTT volume - DWI volume ≥50 ml. Mismatch classifications using the ≥ 50 ml definition were compared by constructing contingency tables. Results: A total of 194 patients met the study criteria and had median DWI and MTT planimetric volumes of 13.06 ml and 99.27 ml respectively. For both the DWI (n=170) and MTT (n=164), 94% of the measurements were within two standard deviations of the difference between the planimetric and approximate volume measurements. Comparing the planimetric and approximate volume measurements, the Spearman correlation coefficients were 0.855 and 0.886 for the DWI and MTT measurements respectively (p<0.01). Compared to the planimetric method, the approximate “XYZ/2” method had a high sensitivity (0.91), specificity (0.80), accuracy (0.86) and positive predictive value (0.85) to detect mismatch using the ≥ 50 ml definition. Compared to the qualitative method, the approximate “XYZ/2” method had a sensitivity (0.77), specificity (0.76), accuracy (0.77) and positive predictive value (0.87) to detect mismatch using the ≥ 50 ml definition. Conclusions: The approximate “XYZ/2” method is sufficient for classifying the presence of MRI determined mismatch in acute stroke patients and therefore is a potential tool when using MRI determined mismatch as an inclusion criteria for clinical trials.

scholarly journals XPERT MYCOBACTERIUM TUBERCULOSIS/RIFAMPICIN ASSAY: A BOON IN TUBERCULOSIS DIAGNOSTICS

2016 ◽  
Vol 9 (5) ◽  
pp. 225 ◽  
Author(s):  
Sevitha Bhat ◽  
Kavya Ramamurthy ◽  
Shalini Shenoy ◽  
Aseem Rangnekar
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Predictive Value ◽  
High Sensitivity ◽  
Mortality And Morbidity ◽  
Indicator Tube ◽  
Promising Tool ◽  
Causes Of Mortality ◽  
Conventional Microscopy ◽  
Tb Diagnostics ◽  
Sensitivity Specificity

ABSTRACTObjectives: Mycobacterium tuberculosis (MTB) remains one of the most significant causes of mortality and morbidity in developing countriesespecially India. India has the highest burden of TB, with an estimated incidence figure of 2.1 million cases out of the 9 million cases of TB globally.Diagnosis of TB relies on conventional microscopy and culture with drawbacks related to sensitivity, specificity, turn around time (TAT). The aim ofthis study was to evaluate the performance of Xpert MTB/rifampicin (RIF) assay (GX) for MTB detection in pulmonary and extrapulmonary clinicalsamples.Methods: A total of 209 clinical specimens (182: pulmonary and 27: extrapulmonary) were processed using auramine smear, culture by mycobacteriagrowth indicator tube and GenXpert.Results: The sensitivity of GenXpert was 62.63% for pulmonary and 55% for extrapulmonary samples. The sensitivity and specificity of GX were100% for the smear positive cases. The sensitivity, specificity, positive predictive value, and negative predictive value of the GX for smear negativecases were 67.8%, 97.5%, 90.4%, and 89.6%, respectively. RIF resistance was detected in 3.8% the samples.Conclusion: GenXpert, with short TAT, high sensitivity, specificity and less technical expertise required is a promising tool in TB diagnostics for thefuture.Keywords: GenXpert, Tuberculosis diagnosis, Molecular method, Rifampicin resistance.

Isolated demyelinating syndromes: comparison of CSF oligoclonal bands and different MR imaging criteria to predict conversion to CDMS

2001 ◽  
Vol 7 (6) ◽  
pp. 359-363 ◽  
Author(s):  
M Tintoré ◽  
A Rovira ◽  
L Brieva ◽  
E Grivé ◽  
R Jardí ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Positive Predictive Value ◽  
Negative Predictive Value ◽  
Predictive Value ◽  
High Sensitivity ◽  
Oligoclonal Bands ◽  
High Negative Predictive Value ◽  
Csf Oligoclonal Bands ◽  
Sensitivity Specificity

Aim of the study: To evaluate and compare the capacity of oligoclonal bands (OB) and three sets of MR imaging criteria to predict the conversion of clinically isolated syndromes (CIS) to clinically definite multiple sclerosis (CDMS). Patients and methods: One hundred and twelve patients with CIS were prospectively studied with MR imaging and determination of OB. Based on the clinical follow-up (conversion or not conversion to CDMS), we calculated the sensitivity, specificity accuracy, positive and negative predictive value of the OB, and MR imaging criteria proposed by Paty et al, Fazekas et al and Barkhof et al. Results: CDMS developed in 26 (23.2%) patients after a mean follow-up of 31 months (range 12-62). OB were positive in 70 (62.5%) patients and were associated with a higher risk of developing CDMS. OB showed a sensitivity of 81%, specificity of 43%, accuracy of 52%, positive predictive value (PPV) of 30% and negative predictive value (NPV) of 88%. Paty and Fazekas criteria showed the same results with a sensitivity of 77%, specificity of 51%, accuracy of 57%, positive predictive value of 32% and negative predictive value of 88%. Barkhof criteria showed a sensitivity of 65%, specificity of 70%, accuracy of 69%, PPV of 40% and NPV of 87%. The greatest accuracy was achieved when patients with positive OB and three or four Barkhof's criteria were selected. Conclusions: We observed a high prevalence of OB in CIS. OB and MR imaging (Paty's and Fazekas' criteria) have high sensitivity. Barkhof's criteria have a higher specificity. Both OB and MR imaging criteria have a high negative predictive value.

Sensitivity, Specificity, and Positive Predictive Value of Technetium 99-HMPAO SPECT in Discriminating Alzheimer's Disease from other Dementias

1997 ◽  
Vol 10 (1) ◽  
pp. 15-21 ◽  
Author(s):  
Donna L. Masterman ◽  
Mario F. Mendez ◽  
Lynn A. Fairbanks ◽  
Jeffrey L. Cummings
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Positive Predictive Value ◽  
Predictive Value ◽  
Single Photon ◽  
Photon Emission ◽  
High Sensitivity ◽  
Hmpao Spect ◽  
Clinical Diagnoses ◽  
Sensitivity Specificity

Investigators have reported high sensitivity and specificity values for single photon emission computerized tomography (SPECT) when distinguishing Alzheimer's disease (AD) patients from normal elderly controls or from selected patient groups. The role of SPECT in identifying AD among unselected patients with memory complaints requires investigation. We examined 139 consecutive patients with 99Tc-HMPAO SPECT. NINCDS-ADRDA diagnoses were determined blind to SPECT results, and scans were read and classified by visual inspection blind to clinical diagnoses. Bilateral temporoparietal hypoperfusion (TP) occurred in 75% of probable, 65% of possible, and 45% of unlikely AD patients, yielding a sensitivity of 75% and a specificity of 52% when comparing probable AD versus unlikely AD groups. A positive predictive value of 78% was obtained based on a 69% prevalence of AD in our total clinic population. Patients with false-positive results included a variety of dementing illnesses; all patients with bilateral hypoperfusion had dementia. A pattern of TP on SPECT scans is seen in most patients with AD, but could be found in other dementias as well and cannot be regarded as specific to AD. Reduced TP perfusion discriminated between demented and nondemented individuals. Further strategies for SPECT interpretation that improve diagnostic specificity should be sought.

A pharmacogenetic model predicting low paclitaxel clearance based on the DMET platform.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 2597-2597
Author(s):  
Annemieke J.M. Nieuweboer ◽  
Anne-Joy M. de Graan ◽  
Laure Elens ◽  
Marcel Smid ◽  
John W. M. Martens ◽  
...  
Keyword(s):  
Positive Predictive Value ◽  
Prediction Model ◽  
Predictive Value ◽  
Plasma Concentrations ◽  
Sampling Strategy ◽  
High Sensitivity ◽  
Cancer Drug ◽  
Drug Metabolizing Enzyme ◽  
Validation Set ◽  
Metabolizing Enzyme

2597 Background: Paclitaxel (PTX) is a commonly used cytotoxic agent. It is metabolized by P450 cytochrome iso-enzymes CYP3A4 and CYP2C8 and has high interindividual variability in pharmacokinetics (PK) and toxicity. Here, we present a genetic prediction model to identify patients with low PTX clearance (CL) using the new Drug-Metabolizing Enzyme and Transporter (DMET; Affymetrix) platform, capable of detecting 1,936 genetic variants (SNPs) in 225 genes. Methods: In a PK study, 270 Caucasian cancer patients were treated with PTX. PK parameters were determined using a limited sampling strategy. HPLC or LC-MS/MS were used to determine PTX plasma concentrations and non-linear mixed effects modelling (NONMEM) was used to estimate individual unbound CL from previously developed PK population models. Subsequently, the cohort of patients was randomly split into a training and validation set. In all patients, the presence of SNPs in metabolic enzymes and transporters was determined using the DMET platform. Selected SNPs were subsequently validated in the validation set. Results: Baseline characteristics were comparable in both sets. The mean CL of the total cohort was 488 ± 149 L/h and the threshold for low CL was set at 339 L/h (1 SD < total mean CL). 14 SNPs were selected to be included in the prediction model and validated in the validation set. For none of these 14 SNPs, evidence for a biological plausible link to taxane metabolism exists. The developed prediction model had a sensitivity of 95% to identify low PTX CL, a positive predictive value of 22% and remained significantly associated with low CL after multivariate analysis correcting for age, gender and Hb levels at start of therapy (P=0.024). Conclusions: This is the first considerably-sized application of the DMET platform to explain PK variability of a widely used anti-cancer drug. Although this validated prediction model for PTX CL had a high sensitivity, its positive predictive value is too low to be of direct clinical use. Likely, genetic variability in DMET genes alone does not sufficiently explain PTX CL, as for example environmental factors may also influence PTX metabolism.

scholarly journals Usefulness of qSOFA and ECOG Scores for Predicting Hospital Mortality in Postsurgical Cancer Patients without Infection

2019 ◽  
Vol 2019 ◽  
pp. 1-5
Author(s):  
Silvio A. Ñamendys-Silva ◽  
Emerson Joachin-Sánchez ◽  
Aranza Joffre-Torres ◽  
Bertha M. Córdova-Sánchez ◽  
Guadalupe Ferrer-Burgos ◽  
...  
Keyword(s):  
Positive Predictive Value ◽  
Hospital Mortality ◽  
Cancer Patients ◽  
Negative Predictive Value ◽  
Predictive Value ◽  
Cox Regression ◽  
High Sensitivity ◽  
Cox Regression Analysis ◽  
Predicting Factors ◽  
Qsofa Score

Background. The quick sequential organ failure assessment (qSOFA) and the Eastern Cooperative Oncologic Group (ECOG) scale are simple and easy parameters to measure because they do not require laboratory tests. The objective of this study was to compare the discriminatory capacity of the qSOFA and ECOG to predict hospital mortality in postsurgical cancer patients without infection. Methods. During the period 2013–2017, we prospectively collected data of all patients without infection who were admitted to the ICU during the postoperative period, except those who stayed in the ICU for <24 hours or patients under 18 years. The ECOG score during the last month before hospitalization and the qSOFA performed during the first hour after admission to the intensive care unit (ICU) were collected. The primary outcome for this study was the in-hospital mortality rate. Results. A total of 315 patients were included. The ICU and hospital mortality rates were 6% and 9.2%, respectively. No difference was observed between the qSOFA [AUC=0.75 (95% CI = 0.69-0.79)] and the ECOG scores [AUC=0.68 (95%CI =0.62-0.73)] (p=0.221) for predicting in-hospital mortality. qSOFA greater than 1 predicted in-hospital mortality with a high sensitivity (100%) but low specificity (38.8%); positive predictive value of 26.3% and negative predictive value of 93.1% compared to 74.4% of specificity, 55.1% of sensitivity%; positive predictive value of 18% and negative predictive value of 94.2% for an ECOG score greater than 1. Multivariable Cox regression analysis identified two independent predicting factors of in-hospital mortality, which included ECOG score during the last month before hospitalization (HR: 1.46; 95 % CI: 1.06-2.00); qSOFA calculated in the first hours after ICU admission (OR: 3.17; 95 % CI: 1.79–5.63). Conclusion. No difference was observed between the qSOFA and ECOG for predicting in-hospital mortality. The qSOFA score performed during the first hour after admission to the ICU and ECOG scale during the last month before hospitalization were associated with in-hospital mortality in postsurgical cancer patients without infection. The qSOFA and ECOG score have a potential to be included as early warning tools for hospitalized postsurgical cancer patients without infection.

scholarly journals Role of imprint cytology in thoracic endoscopy suite

2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Mohammed Elsaid Hantera ◽  
Salwa Atef Ganna ◽  
Ayman Mohamed Elsaka ◽  
Walaa Mowafy El-Lawaty
Keyword(s):  
Positive Predictive Value ◽  
Negative Predictive Value ◽  
Predictive Value ◽  
Fiberoptic Bronchoscopy ◽  
High Sensitivity ◽  
Added Value ◽  
Imprint Cytology ◽  
Medical Thoracoscopy ◽  
Multiple Biopsies ◽  
Sensitivity Specificity

Abstract Background Fiberoptic bronchoscopy and medical thoracoscopy are basic interventional modalities for the diagnosis of a wide variety of pleuropulmonary diseases. In some cases, we need fast and accurate results for decision-making. We aimed to evaluate the diagnostic accuracy of imprint cytology and its added value to the pulmonologist. Results Multiple biopsies were taken from 54 patients included 31 patients with lung masses subjected to fiberoptic bronchoscopy and 23 patients with undiagnosed exudative pleural effusion subjected to medical thoracoscopy. Imprint cytology was done to all biopsies which are later examined histopathologically. Regarding fiberoptic bronchoscopy biopsies, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of imprint cytology were 93.33, 100, 100, 33.33, and 93.55%, respectively. While in medical thoracoscopy biopsies, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of imprint cytology were 94.74, 100, 100, 80, and 95.65%, respectively. Conclusion Imprint cytology is an easy, rapid, and reliable method that has a high sensitivity and specificity in the diagnosis of lung and pleural malignancies compared with histopathology.

scholarly journals Diagnostic Test On Modified Score Of Cesarean Section History In Placenta Accreta Index In Predicting Placenta Accreta Diagnosis In Rsup Dr M Djamil

2021 ◽  
Vol 5 (2) ◽  
pp. 215-230
Author(s):  
Widayat Widayat ◽  
Andi Friadi ◽  
Hafni Bacthiar
Keyword(s):  
Caesarean Section ◽  
Positive Predictive Value ◽  
Negative Predictive Value ◽  
Diagnostic Test ◽  
Predictive Value ◽  
Placenta Accreta ◽  
High Sensitivity ◽  
Kappa Score ◽  
Chorionic Villi ◽  
History Of

Introduction : Placenta accreta is defined as abnormal implantation of placenta villi which invades myometrium without the presence of decidua bacalis resulting in placenta that is difficult to remove. Based on the depth of invasion, placenta accreta is divided into three grades, placenta accreta, placenta increta, and placenta percreta. Placenta accreta developes if chorionic villi attaches to endometrium beyond desidua basalis. Placenta increta develops when chorionic villi invades the whole myometrium. Placenta percreta developes when chorionic villi attaches beyond myometrium reaching serous and abdominal organ. Based on clinical manifestation, placenta accreta is the common term being used. Incident of abnormal placenta invasion varies from 1 : 93.000 up to 1 : 540 pregnancy. PA incidence had increased four times from 1994 to 2002 in line with increased of caesarean section procedure. Other study showed history of caesarean section increased risk of placenta accreta up to 8,7 times. Placenta accreta index (PAI) was developed based on scoring process or various parameters assessment to help diagnose placenta accreta. The parameters including: history of caesarean section ≥ 2 times, lacunae grade, sagittal smallest myometrial thickness, anterior placenta previa and birding vessel. High PAI indicates high risk of abnormal placenta invasion based on histology.Objective : This study aims to investigate modified history of cesarean section score in placenta accreta index in predicting placenta accreta diagnosis in RSUP DR M  Djamil Padang.Material and methods : This was analytical study with cross sectional design. Study population was 84 placenta accreta patients in RSUP Dr. M. Djamil Padang from 2016 to 2019. Study sample was recruited using simple random sampling technique after meeting inclusion and exclusion criteria. Statistic analysis was done using Cohen’s Kappa test. Diagnostic test including sensiticivy, specivicity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy.Result : Strenght of agreement diagnosis placenta accreta based on PAI showed Kappa score of -0,002 (Kappa score < 0,2) which indicated  poor strength of agreement. Strenght of agreement diagnosis placenta accreta based on modified PAI showed Kappa score of 0,353 (Kappa score range from 0,21 to 0,40) which indicated fair strength of agreement. PAI diagnostic test yield sensitivity of 97,1%, specificity of 2,8%, positive predictive value of 48,5%, negative predictive value of 50%, and accuracy of 48,6%. Modified PAI diagnostic test yield sensitivity of 97,1%, specificity of 38,9%, positive predictive value of 60%, negative predictive value of 93,3%, and accuracy of 67,1%.Conclusion : PAI has high sensitivity, low specificity, moderate positive predictive value, moderate negative predictive value, and moderate accuration. Modified PAI has high sensitivity, moderate specificity, moderate positive predictive value, high negative predictive value, and high accuracy. PAI diagnosis has poor strength of agreement compared with pathology anatomy. Modified PAI diagnosis has fair strength of agreement compared with pathology anatomy. Modified PAI has identical sensitivity with standard PAI, meanwhile for specificity, positive predictive value, negative predictive value, and accuracy, modified PAI yields higher result compared to PAI.Keywords: Modified score of history caesarean section, placenta accreta index, Modified placenta accreta index, diagnostic test of placenta accreta diagnosis

scholarly journals The Early Warning And Response System (EWARS-TDR) For Dengue Outbreaks: Can It Also Be Applied To Chikungunya And Zika Outbreak Warning?

2021 ◽  
Author(s):  
Rocio Cardenas ◽  
Laith Hussain-Alkhateeb ◽  
David Benitez-Valladares ◽  
Gustavo Sanchez-Tejeda ◽  
Axel Kroeger
Keyword(s):  
Positive Predictive Value ◽  
Early Warning ◽  
Predictive Value ◽  
Large City ◽  
High Sensitivity ◽  
Surveillance Systems ◽  
Insect Vector ◽  
Alarm Signals ◽  
Response System ◽  
Dengue Outbreaks

Abstract Background. In the Americas, endemic countries for Aedes-borne diseases such as dengue, chikungunya, and Zika face great challenges particularly since the recent outbreaks of CHIKV and ZIKV, all transmitted by the same insect vector Aedes aegypti and Ae. albopictus. The Special Program for Research and Training in Tropical Diseases (TDR- WHO) has developed together with partners an early warning and Response System (EWARS) for dengue outbreaks based on a variety of alarm signals with a high sensitivity and positive predictive value (PPV). The question is if this tool can also be used for the prediction of Zika and chikungunya outbreaks.Methodology. We conducted in nine districts of Mexico and one large city in Colombia a retrospective analysis of epidemiological data (for the outbreak definition) and of climate and entomological data (as potential alarm indicators) produced by the national surveillance systems for dengue, chikungunya and Zika outbreak prediction covering the following outbreak years: for dengue 2012-2016, for Zika 2015-2017, for chikungunya 2014-2016. This period was divided into a “run in period” (to establish the “historical” pattern of the disease) and an “analysis period” (to identify sensitivity and PPV of outbreak prediction). Results. In Mexico, the sensitivity of alarm signals for correctly predicting an outbreak was 92% for dengue, and 97% for Zika (chikungunya data could not be obtained in Mexico); the PPV was 68% for dengue and 100% for Zika. The time period between alarm and start of the outbreak (i.e. the time available for early response activities) was for dengue 6-8 weeks and for Zika 3-5 weeks. In Colombia the sensitivity of the outbreak prediction was 92% for dengue, 93% for chikungunya and 100% for Zika; the PPV was 68% for dengue, 92% for chikungunya and 54% for Zika; the prediction distance was for dengue 3-5 weeks, for chikungunya 10-13 weeks and for Zika 6-10 weeks. Conclusion. The implementation of an early warning and response system (EWARS) could predict outbreaks of three Aedes borne diseases with a high sensitivity and positive predictive value and with a lag time long enough for preparing an adequate outbreak response in order to reduce the magnitude or avert the occurrence of outbreaks with their elevated social and economic tolls.

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