Carestart malaria hrp2 pf

Project was approved by Haitian IRB and not considered human subjects research by CDC Human Subjects Office (2015–155). Dried blood on filter paper was collected from March 2016- December 2017 from five health facilities in Haiti from symptomatic persons testing positive for P. falciparum malaria by rapid diagnostic test, CareStart Malaria HRP2 (Pf) (CareStart^TM, Access Bio, USA). Patients of all ages were enrolled after consenting to test for molecular markers of malaria drug resistance. Whole blood was collected by finger prick on Whatman 903 Protein Saver cards (GE Healthcare). Each filter paper was air-dried overnight, stored in a desiccant containing bag at 4°C until shipment to CDC in Atlanta, GA. A 100 samples previously described [5 (link)] were chosen based on their Ct values for this method validation study. These samples had Ct values ranging from 21–40, and were selected since this Ct range had a wide distribution of parasites/μL (~ 0.2–71,000 parasites/μL).

The CareStart™ Malaria HRP2 pf (CAT NO: G0141, ACCESSBIO) Ag RDT is a chromatographic test for in vitro diagnosis. It has a long shelf-life of more than 1 year, with storage conditions ranging from 1 to 40 °C. Each kit is composed of 25 chromatographic test strips fixed in a cassette, lysis buffer, a pack of 25 lancets and disposable alcohol swabs saturated with 70% isopropyl for disinfection. The CareStart™ Malaria Pf (HRP2) Ag RDT contains a membrane strip pre-coated with a monoclonal antibody as a single line across the test strip conjugated to a signal, typically colloidal gold. The monoclonal antibody is specific to HRP2 of P. falciparum.Each CareStart™ Malaria Pf (HRP2) Ag RDT device was labelled with an identification code like that used on the slide for each study participant. Approximately 5 μL of venous blood was added onto the test device window using the sample applicator provided with the kit. This was followed by adding 2 drops (60 μL) of reagent buffer. The device was allowed untouched for 20 min at room temperature, and the result was recorded as per the instruction of the manufacturer. Negative results were recorded when only a band appeared on the control area whereas the presence of two bands, one band in the control area and the other band in the test area were recorded as a positive result for P. falciparum.

A longitudinal cohort of households across three villages (Kinesamo, Maruti, and Sitabicha) in Bungoma county, Kenya was established in June 2017 and followed until July 2018. The three villages were selected based on their high malaria prevalence in a previous cross-sectional study^{61 (link)}. All household members in participating households over the age of 1 year were offered enrollment. Sample collection details have been reported⁶² . For each participant, demographic and behavioral questionnaires were administered and dried blood spot (DBS) samples were collected every month. The DBS were tested for P. falciparum parasites using real-time PCR post hoc (see below), and therefore parasites detected in asymptomatic people were not treated. Participants contacted the study team at any time when experiencing symptoms consistent with malaria, at which time they were tested for malaria using a rapid diagnostic test (RDT) (Carestart © Malaria HRP2 Pf from Accessbio)⁶³ and, if positive, treated with Artemether-Lumefantrine. DBS were also collected at the time of RDT testing. One morning each week, indoor resting mosquitoes were collected from participant households using vacuum aspiration with Prokopacks⁶⁴ . From these collections, female Anopheles mosquitoes were identified morphologically and transected to separate the abdomen from the head and thorax.