Richar Ivan Rodríguez-Hidalgo

Dr. Richar Ivan Rodríguez-Hidalgo

Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Pichincha, Ecuador
orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
7 March 2013 in Tropical Medicine & International Health
Verified
Journal Article
Open access
PDF file
NPNicolas Praet
Nicolas Praet
JVJaco J. Verweij
Jaco J. Verweij
KMKabemba E. Mwape
Kabemba E. Mwape
IPIsaac K. Phiri
Isaac K. Phiri
JMJohn B. Muma
John B. Muma
SGSarah Gabriël
Sarah Gabriël
Objective: To estimate and compare the performances of coprology, copro‐Ag ELISA and real‐time polymerase chain reaction assay (copro‐PCR) for detection of Taenia solium tapeworm carriers.Methods: The three diagnostic tests were applied on 817 stool samples collected in two Zambian communities where taeniasis is endemic. A Bayesian approach was used to allow estimation of the test characteristics. Two (0.2%; 95% Confidence Interval (CI): 0–0.8), 67 (8.2%; 95% CI: 6.4–10.3) and 10 (1.2%; 95% CI: 0.5–2.2) samples were positive using coprology, copro‐ Ag ELISA and copro‐PCR, respectively.Results: Specificities of 99.9%, 92.0% and 99.0% were determined for coprology, copro‐ Ag ELISA and copro‐PCR, respectively. Sensitivities of 52.5%, 84.5% and 82.7% were determined for coprology, copro‐ Ag ELISA and copro‐PCR, respectively.Conclusions: We urge for additional studies exploring possible cross‐reactions of the copro‐ Ag ELISA and for the use of more sensitive tests, such as copro‐PCR, for the detection of tapeworm carriers, which is a key factor in controlling the parasite in endemic areas.

1 January 2007 in Journal of Food Protection
Verified
Journal Article
Closed access
DGDirk Geysen
Dirk Geysen
KKKirezi Kanobana
Kirezi Kanobana
BVBjorn Victor
Bjorn Victor
Richar Ivan Rodríguez-HidalgoRichar Ivan Rodríguez-Hidalgo
Richar Ivan Rodríguez-Hidalgo
JBJean De Borchgrave
Jean De Borchgrave
PDPierre Dorny
Pierre Dorny
Bovine cysticercosis is a zoonosis caused by the larval stage (cysticercus) of the human tapeworm Taenia saginata. Infected cattle is an important food safety issue besides an economic concern. Hum...

1 January 2010 in International Journal for Parasitology
Verified
Journal Article
Closed access
NPN. Praet
N. Praet
NSNiko Speybroeck
Niko Speybroeck
Richar Ivan Rodríguez-HidalgoRichar Ivan Rodríguez-Hidalgo
Richar Ivan Rodríguez-Hidalgo
WBW. Benitez-Ortiz
W. Benitez-Ortiz
DBD. Berkvens
D. Berkvens
PDP. Dorny
P. Dorny

7 April 2017 in PLOS ONE
Verified
Journal Article
Open access
PDF file
Richar Ivan Rodríguez-HidalgoRichar Ivan Rodríguez-Hidalgo
Richar Ivan Rodríguez-Hidalgo
XPXimena Pérez-Otáñez
Ximena Pérez-Otáñez
SGSandra Garcés-Carrera
Sandra Garcés-Carrera
SVSophie Vanwambeke
Sophie Vanwambeke
MMMaxime Madder
Maxime Madder
WBWashington Benítez-Ortiz
Washington Benítez-Ortiz
Rhipicephalus microplus is widely distributed in tropical and subtropical areas of the world where livestock is a principal activity with great veterinary and economic importance. In Ecuador, this hematophagous ectoparasite has been observed between 0 and 2600 masl. One of the main tick control measures is the use of acaricides, which have been indiscriminately used worldwide and in Ecuador. In this country, no studies on acaricide resistance in Rhipicephalus microplus have been published. The current study aims to characterise the level of resistance of R. microplus against three main acaricides commonly used in Ecuador i.e. amitraz, alpha-cypermethrin and ivermectin to determine the level and pattern of dose-responses for R. microplus in 12 field populations (farms). The level of acaricide resistance was evaluated using three different bioassays: adult immersion test (AIT), larval package test (LPT) and larval immersion test (LIT), as recommended by the FAO. The predictive dose-responses were analysed by binomial logistics regression of the larval survival rate (resistance). In general, we found resistance of 67% for amitraz; 50% for alpha-cypermethrin and from 25 to 42% for ivermectin in the twelve field populations analysed. Resistance levels were studied in larval and adult bioassays, respectively, which were slightly modified for this study. For larval bioassays based on corrected mortality i.e. high (above 51%), medium (21–50%) and low (11–20%) resistance, percentages less than 10% were considered as susceptible. For the adult test, two resistance levels were used i.e. high (more than 76%) and medium (51 to 75%) resistance. Percentages lower than 50% were considered as susceptible. In this context, for larval bioassays, amitraz showed 21%, 38% and 8% for high, medium and low resistance, respectively. Alpha-cypermethrin presented 8%, 4 and 38% for high, medium and low resistance, respectively. Ivermectin presented 8%, 25% and 8% for high, medium and low resistance, respectively. For adult tests with amitraz 50% and 17% of the field populations showed average and high resistance, with evidences of average resistance to alpha-cypermethrin in 50% of the samples and average resistance against ivermectin in 25% of the farms. No statistical difference amongst the three bioassays was found and acaricide resistance was confirmed by logistic regression analysis; hence resistance (dose-responses) in each field populations differed, depending on the choice of the acaricide, frequent usage, frequency of treatment and farm management. The effective estimated dose needed to eliminate 99% of ticks is higher than dose recommended by the manufacturer. In conclusion, amitraz showed the highest resistance followed by ivermectin and alpha-cypermethrin and reveals differences on resistance in each individual field population. This information is important in order to establish the monitoring of resistance on each farm individually, contributing to the rational use of acaricides included in an integrated control program for R. microplus.

5 August 2010 in The American Journal of Tropical Medicine and Hygiene
Verified
Journal Article
Closed access
NPNicolas Praet
Nicolas Praet
Richar Ivan Rodríguez-HidalgoRichar Ivan Rodríguez-Hidalgo
Richar Ivan Rodríguez-Hidalgo
NSNiko Speybroeck
Niko Speybroeck
SASerge Ahounou
Serge Ahounou
WBWashington Benitez-Ortiz
Washington Benitez-Ortiz
PDPierre Dorny
Pierre Dorny
Taenia solium cysticercosis is an endemic zoonosis in many developing countries. Serological tests are the most appropriate diagnostic tools to understand the transmission dynamics of the parasite, but the performances of these methods in such a setting are not known. A south Ecuadorian human population living in an endemic area was tested using three common serological tests. Because none of them is a gold standard, a Bayesian Latent Class analysis was used to estimate the test characteristics. Two definitions of a case were considered to differentiate between prevalence of current infection and prior exposure to the parasite. Differences between the performances of the same test in function of the definition of a case were observed. This study shows that test results and prior information should be interpreted carefully in a Bayesian analysis framework, particularly when the latter is based on clinical studies.

1 October 2002 in Journal of Parasitology
Verified
Journal Article
Closed access
PDF file
Richar Ivan Rodríguez-HidalgoRichar Ivan Rodríguez-Hidalgo
Richar Ivan Rodríguez-Hidalgo
DGD. Geysen
D. Geysen
WBW. Benítez-Ortiz
W. Benítez-Ortiz
SGS. Geerts
S. Geerts
JBJ. Brandt
J. Brandt
Given the constraints of classical diagnostic methods, i.e., morphological and isoenzymatic studies of proglottids, a polymerase chain reaction test complemented with restriction enzyme analysis has been modified by redesigning one of the primers to reduce nonspecific amplifications experienced when using field samples. The use of these new, highly cestode-specific primers and the restriction enzyme DdeI led to the development of a diagnostic assay that clearly distinguishes between Taenia saginata and T. solium proglottids in field samples. This assay confirms the presence of T. saginata in Ecuador. DNA amplification of some of these taeniids showed different patterns, suggesting the possibility that strain differences exist. These results demonstrate the need for development of useful molecular assays as reliable tools for epidemiological studies on cestodes.