title: The Utility of Malaria Rapid Diagnostic Tests as a Tool in Enhanced Surveillance for Malaria Elimination in Vanuatu.
abstract: BACKGROUND
  As part of efforts to eliminate malaria, Vanuatu has piloted the implementation of enhanced malaria surveillance and response strategies since 2011. This involves passive case detection (PCD) in health facilities, proactive case detection (Pro-ACD) and reactive case detection (Re-ACD) in communities using malaria rapid diagnostic tests (RDTs). While RDTs improve case management, their utility for detection of malaria infections in ACDs in this setting is unclear.
  
  
  METHODS
  The utility of malaria RDTs as diagnostic tools was evaluated in PCD, in five rounds of Pro-ACDs and five rounds of Re-ACDs conducted in Tafea and Torba Provinces between 2011 and 2014. The number of malaria infections detected by RDTs was compared to that detected by PCR from collected used-RDTs.
  
  
  RESULTS
  PCD in Tafea Province (2013) showed a RDT-positive rate of 0.21% (2/939) and a PCR-positive rate of 0.44% (2/453), indicating less than 1% of suspected malaria cases in Tafea Province were due to malaria. In Pro-ACDs conducted in Tafea and Torba Provinces, RDT-positive rates in 2013 and 2014 were 0.14% (3/2145) and 0% (0/2823), respectively, while the corresponding PCR-positive rates were 0.72% (9/1242) and 0.79% (9/1141). PCR identified villages in both provinces appearing to be transmission foci with a small number of low-density infections, mainly P. falciparum infections. In five rounds of Re-ACD, RDTs did not identify any additional infections while PCR detected only one among 173 subjects screened.
  
  
  CONCLUSIONS
  PCD and Pro-ACDs demonstrate that both Tafea and Torba Provinces in Vanuatu has achieved very low malaria prevalence. In these low-transmission areas, conducting Pro-ACD and Re-ACDs using RDTs appears not cost-effective and may have limited impact on interrupting malaria transmission due to the small number of infections identified by RDTs and considerable operational resources invested. More sensitive, field deployable and affordable diagnostic tools will improve malaria surveillance in malaria elimination settings.
authors.affiliation: Malaria & Vector Borne Diseases Control (MVBDC), Ministry of Health, Port Vila Vanuatu.
authors.forename: Wesley
authors.initials: W
authors.lastname: Donald
authors.affiliation: Drug Resistance and Diagnostics, Australian Army Malaria Institute, Brisbane, Australia.|Clinical Tropical Medicine, QIMR-Berghofer Medical Research Institute, Brisbane, Australia.
authors.forename: Cielo
authors.initials: C
authors.lastname: Pasay
authors.affiliation: World Health Organization, Vanuatu Country Office, Port Vila, Vanuatu.
authors.forename: Jean-Olivier
authors.initials: JO
authors.lastname: Guintran
authors.affiliation: Malaria & Vector Borne Diseases Control (MVBDC), Ministry of Health, Port Vila Vanuatu.
authors.forename: Harry
authors.initials: H
authors.lastname: Iata
authors.affiliation: Drug Resistance and Diagnostics, Australian Army Malaria Institute, Brisbane, Australia.|Clinical Tropical Medicine, QIMR-Berghofer Medical Research Institute, Brisbane, Australia.
authors.forename: Karen
authors.initials: K
authors.lastname: Anderson
authors.affiliation: Malaria & Vector Borne Diseases Control (MVBDC), Ministry of Health, Port Vila Vanuatu.
authors.forename: Johnny
authors.initials: J
authors.lastname: Nausien
authors.affiliation: Drug Resistance and Diagnostics, Australian Army Malaria Institute, Brisbane, Australia.|Clinical Tropical Medicine, QIMR-Berghofer Medical Research Institute, Brisbane, Australia.
authors.forename: Karryn J
authors.initials: KJ
authors.lastname: Gresty
authors.affiliation: Walter Reed Army Institute of Research, Malaria Vaccine Branch, Military Malaria Research Program, Silver Spring, Maryland, United States of America.
authors.forename: Norman C
authors.initials: NC
authors.lastname: Waters
authors.affiliation: World Health Organization, Western Pacific Reginal Office, Manila, Philippines.
authors.forename: Lasse S
authors.initials: LS
authors.lastname: Vestergaard
authors.affiliation: Malaria & Vector Borne Diseases Control (MVBDC), Ministry of Health, Port Vila Vanuatu.
authors.forename: George
authors.initials: G
authors.lastname: Taleo
authors.affiliation: Drug Resistance and Diagnostics, Australian Army Malaria Institute, Brisbane, Australia.|Clinical Tropical Medicine, QIMR-Berghofer Medical Research Institute, Brisbane, Australia.
authors.forename: Qin
authors.initials: Q
authors.lastname: Cheng
mesh_terms: D003955:Diagnostic Tests, Routine / Q000706:statistics & numerical data*; D062665:Epidemiological Monitoring; D006801:Humans; D008288:Malaria / Q000175:diagnosis* / Q000453:epidemiology*; D015995:Prevalence; D011795:Surveys and Questionnaires; D013997:Time Factors; D009514:Vanuatu / Q000453:epidemiology