Induced Blood-Stage Malaria in Healthy Malaria-Naive Adults to Assess the Safety and Infectivity of Plasmodium Vivax Challenge Agent and Evaluate Transmission in Mosquito Feeding Assays

Eligibility Criteria

• 1. Age \>=18 and \<=54 years.
• 2. RBCs positive for Duffy antigen/chemokine receptor.
• 3. Malaria comprehension exam passed prior to study activities.
• 4. Suitable accommodation and reliable access to the NIHCC for the duration of the study in the opinion of the investigator.
• 5. Persons of childbearing potential must be willing to use reliable contraception from 28 days prior to challenge agent administration to the end of study.
• 6. Signing of the informed consent form.
• 7. Agreement to not live alone from challenge agent administration until the completion of antimalarial treatment.
• 8. Agreement to long-term storage of study samples for future research.
• 1. Planned travel to a P. vivax-endemic area during the study period (see https://www.cdc.gov/malaria/travelers/country_table/a.html).
• 2. History of travel to or residence in a P. vivax malaria-endemic region for more than 2 weeks during the past 2 years.
• 3. Prior confirmed P. vivax malaria diagnosis or clinical history consistent with likely P. vivax infection. At the investigator s discretion, participants may be enrolled if the exposure was remote, e.g., \> 5 years ago.
• 4. Poor peripheral venous access, at the discretion of the investigator.
• 5. For persons of childbearing potential:
• 6. Being a current or former study team member or clinical trial staff with direct involvement of the trial, or being an employee supervised by a study team member.
• 7. Unwillingness to defer blood donations for at least 3 years.
• 8. Use of any of the following within the specified periods:
• 9. Clinically significant medical condition, physical examination findings, other clinically significant abnormal laboratory results, or past medical history including:
• 10. History of a severe reaction to arthropod bites, or history of anaphylaxis or severe unexpected allergy to any substance.
• 11. Screening blood test or urinalysis laboratory parameters outside of local lab normal range (including infectious serologies). Participants may be included at the investigator s discretion for not clinically significant values outside of normal range.
• 12. Any other finding that, in the judgment of the investigator, would interfere with, or serve as a contraindication to, protocol adherence, assessment of safety or reactogenicity, or a participant s ability to give informed consent, or increase the risk of having an adverse outcome from participating in the study.