Update of Results and Future work: Molecular Surveillance for HRP2 and HRP3 Genetic Deletions in South and Central America

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1 Update of Results and Future work: Molecular Surveillance for HRP2 and HRP3 Genetic Deletions in South and Central America Venkatachalam (Kumar) Udhayakumar Malaria Branch Centers for Disease Control and Prevention, Atlanta AMI/RAVREDA XV Annual Evaluation Meeting Bogota, Colombia 3 5 May 2016

2 Malaria Rapid Diagnostic Tests (RDTs) Malaria RDTs are parasite antigen capture based tests that detect Plasmodium falciparum histidine rich protein 2 (PfHRP2) lactate dehydrogenase (pldh), or aldolase enzyme Majority of commercial RDTs designed to detect PfHRP2 antigen Deletion of the gene encoding PfHRP2 (pfhrp2) in natural P. falciparum populations led to false negative test results. This was discovered by chance in Peru during parasite collection for WHO evaluation of RDTs (Gamboa D. et al PLoS One). Molecular surveillance was conducted in 6 countries between to monitor the deletion of pfhrp2 and pfhrp3 genes in South America Ex 2

3 Molecular Surveillance for HRP 2 and HRP 3 Genetic Deletions in South America ( ) Purpose: Determine the extent of HRP 2 and HRP 3 genetic deletions in P. falciparum populations of South America (using prospectively collected samples). Retrospectively determine the origin and population history of the HRP 2 and HRP 3 deletions in South America through archived samples.

4 Basic Protocol Febrile patient, >5 yr., Microscopic diagnosis or pldh RDT Single Pf infection, inform & consent 3 ml venous blood draw or FTA filter paper, information form, thick & thin film 3 aliquots of plasma and cells each (local and national reference material) Molecularly analyze cell samples: 1. test for species specific 18S rrna gene and MSP2 2. Pf HRP2/3 and 3. flanking genes Total 8 different PCR with many repetitions (tricky test) Quantitatively assay plasma for HRP2 4

5 Genes of Interest in HRP 2 Locus HRP2: Located on chromosome 8 Contains numerous histidine repeats (key trait exploited by RDTs for detection) Mal8P1_230 and Mal8P1_228 are the immediate upstream and downstream genes respectively bp 6490 bp 1022 bp Mal8P1.230 Hypothetical /Pseudogene 1063 bp Mal8P1.231 HRP bp Mal8P1.228 Heat Shock

6 Genes of Interest in HRP 3 Locus HRP3: Located on chromosome 13 near the telomeric region. Also contains numerous histidine repeats. Mal13P1_485 and Mal13P1_475 are the immediate upstream and downstream genes respectively bp 4622 bp 2006 bp Mal13P1.475 Plasmodium Exported protein unknown function 977 bp Mal13P1.480 HRP bp Mal13P1.485 Acyl-CoA synthetase

7 What are the survey results?

8 Distribution of pfhrp2 and pfhrp3 negative P. falciparum isolates in South America 7.5 % 45% (N=40) 33.3 % 53.8% (N=93) Colombia Peru Acre 31% 38% (N=84 ) 0% 0% (N=97) Rondonia 7% 22% (N=61) Bolivia Guyana Para 0% 50.8% (N=59) Brazil Suriname 15% 30% (N=204) 14.1% 3.8% (N=78) 4 % 68% (N=25) 8

9 Distribution of pfhrp2-negative P. falciparum isolates in South America COLOMBIA PERU?? GUYANA SURINAME BRAZIL KEY Study sites BOLIVIA Pfhrp2 negative parasites present 9

10 Human migration has contributed to the spread of B V1 strain with HRP2/HRP3 deletion in areas where Pf was eliminated COLOMBIA GUYANA SURINAME Tumbes [ ] (N=52) PERU Loreto Cusco [Nov Dec 2013] [N=4) BOLIVIA BRAZIL Pf B V1 strain with multidrug resistant and HRP2/3 deleted genotype is spreading rapidly and found in 3 countries Easily adapted to new vectors and ecological zones Stop the spread of this strain 10

11 What about pfhrp2 deletion in Ecuador? (did not participate in prospective surveillance) Esmeraldas outbreak Feb 2013 to Nov samples analyzed and one sample was lacking pfhrp2 but serological confirmation not done appears to be imported case Dr. Fabian Saenz from Quito Saenz FE et al., Malaria Journal, 2015, Dec 10:13

12 What about HRP2/HRP3 deletion in Central America and the Island of Hispaniola?

13 Honduras HRP2/HRP3 deletion survey No HRP2 deletion 44% HRP3 deletion San Pedro Sula Honduras Dr. Rosa Elena Mejia and Dr. Tamara Mancero Total number of samples: 68 Tegucigalpa Limitations: Small sample size from one region Puerto Lempira Abdallah JF et al., Malaria Journal, 2015, 14(19)

14 Ex Major findings from the pfhrp2 and pfhrp3 deletion surveillance ( ) Deletion of pfhrp2 and pfhrp3 was found in 5/6 countries and occurs in multiple genetic backgrounds Deletion was found in Peru, Brazil, Bolivia, Colombia and Suriname Guyana was the only country in which no deletion of these two genes was found Deletion was widely distributed in various parts of Peru In Brazil and Colombia deletion was found in high proportions only in some regions (Amazon region) Pfhrp2 deleted parasites were found to spread through human migrations 14

15 Training and Capacity Development (1) Katherine Jessica Torres-Fajardo, (Dioni s lab) IMTAH, Univ. Cayetano, Peru (7/20/09 to 9/18/2009) Claribel Murillo-Solano, CIDEIM, Cali, Columbia (Feb 14, 2010 to March 27, 2010) Lucia Ortiz-Batsche and Maria E. Castellanos-Reynosa, Univasidad de Valle of Guatemala, Guatemala (March 21 to April 17, 2010) Gustavo A. Fontecha-Sandoval, Universidad Nac. Autonoma de (Honduras) and Meisy E. Mendoza-Montoya, Laboratorio de Malaria, Tegucigalpa, Honduras (Jan 22-Feb 23, 2011)

16 Training and Capacity Development (2) Molecular Training Workshop for the detection of HRP2/3 genetic deletions, Instituto Evandro Chagas, Belem, Brazil (Aug 30 th Sep 10 th, 2010) Trainees from 5 sites in Brazil (IEC, Belem is national reference lab) Guyana (Javin Chandrabose) Suriname (Mergiory Y Bracho Garrido) Dr. Fabian from Ecuador was trained in July staff trained and capacity for HRP2 deletion detection established in Peru, Colombia, Brazil, Suriname, Ecuador and Honduras. Guyana, Guatemala and Nicaragua has the potential for this capacity and needs some additional investment 16

17 Reports An interim progress report was submitted in October 2012 to AMI/PAHO and country partners Final report submitted in AMI/RAVREDA meeting in 2013 in Peru Results were also presented in ASTMH symposium in November (13 17) 2013 Five manuscripts published (Guyana/Suriname, Colombia, Peru, Honduras and Ecuador), Brazil/Bolivia manuscript cleared for submission, and one more Peru manuscript in draft stage) AMI website and other local media publications (LinksMedia) 17

18 What are the implications? HRP 2 based RDTs are not ideal for South American countries especially in the amazon region. Non HRP 2 based RDTs will be appropriate for this region. With limited surveillance data so far there is no evidence for presence of HRP 2 deleted parasites in central American region but further surveillance is necessary to confirm this. If countries continue to use HRP 2 based RDTs they need to plan a periodic molecular surveillance to determine the suitability of using such tests. What is the cutoff for changing use of HRP2 based RDTs (policy issue and 10% deletion suggested provisionaly)? 18

19 Future Plan? Amazon regions can consider using non-pfhrp2 based RDTs but there are challenges In areas where pfhrp2 based tests are used periodic surveillance for detection of pfhrp2 deletion is needed (3 year interval) Invest in developing new cost effective and practical tools for robust surveillance is needed as molecular surveillance is technically challenging

20 What are the best strategies? Integration of surveillance activity (diagnostic resistance, drug resistance and other surveillance activities) can be cost effective and sustainable MOH Partnership with local partnership (academic institutions/ngo etc) and international collaboration (research and QA/QC etc) is critical Commitment from countries to invest in this activity is needed

21 Who has the local lab capacity? Lab capacity established in Peru, Colombia, Ecuador, Brazil, Suriname and Honduras CDC can assist with QA/QC (confirm results using a subset of samples) and support additional training and performance as needed Other partners can be engaged 21

22 New tools? Multiplex tools such as Luminex platform can be explored for serology based surveillance (this has the potential for integration into a multidisease surveillance efforts) Needs some investment in research to get new reagents and optimize tools Advances in genomics can be exploited to identify better targets for next generation RDTs

23 Haiti Study 2012-Serological Response Measures can be Used to Develop Potential Transmission Risk Area Maps (work in progress Rogier E. et al unpublished) Haiti study 2012 MSP-1 19 Serum eluted from >5,000 blood spots Antibody measured using ELISA and Luminex Luminex had low background and yielded better data Serology data converted to seroprevalence curves and data plotted on this map

24 UPCH/PERU Dionicia Gamboa Kathy Torres Jorge Bendezu INS/PERU Nancy Arrospide NAMRU 6/PERU G. Christian Baldeviano Andres G. Lescano BOLIVIA Arletta Anez CDIEM/COLOMBIA Claribel Murillo Erika Dorado PUCE/ECUADOR Fabian E. Saenz Enrique Castro Acknowledgements GUYANA/PAHO Nicholas Cerron BRAZIL Marinete M. Povoa Giselle M. Rachid Viana Danielle R. Lima Suiane C. Negreiros do Valle Luis Marcelo A. Camargo Ricardo Luiz D. Machado SURINAME Malti Adhin PAHO Keith Carter Maria Paz FIND David Bell Mark Perkins Sandra Incardona CDC MALARIA BRANCH Sheila Akinyi Joseph F. Abdallah Curtis S. Huber Ira F. Goldman Luciana M. Flannery Lindsay C. Morton Tonya Mixson Alexandre Macedo de Oliveira John W. Barnwell Venkatachalam Udhayakumar Funding 24

25 Gracias!