title: Controlled human malaria infection of Tanzanians by intradermal injection of aseptic, purified, cryopreserved Plasmodium falciparum sporozoites.
abstract: Controlled human malaria infection (CHMI) by mosquito bite has been used to assess anti-malaria interventions in > 1,500 volunteers since development of methods for infecting mosquitoes by feeding on Plasmodium falciparum (Pf) gametocyte cultures. Such CHMIs have never been used in Africa. Aseptic, purified, cryopreserved Pf sporozoites, PfSPZ Challenge, were used to infect Dutch volunteers by intradermal injection. We conducted a double-blind, placebo-controlled trial to assess safety and infectivity of PfSPZ Challenge in adult male Tanzanians. Volunteers were injected intradermally with 10,000 (N = 12) or 25,000 (N = 12) PfSPZ or normal saline (N = 6). PfSPZ Challenge was well tolerated and safe. Eleven of 12 and 10 of 11 subjects, who received 10,000 and 25,000 PfSPZ respectively, developed parasitemia. In 10,000 versus 25,000 PfSPZ groups geometric mean days from injection to Pf positivity by thick blood film was 15.4 versus 13.5 (P = 0.023). Alpha-thalassemia heterozygosity had no apparent effect on infectivity. PfSPZ Challenge was safe, well tolerated, and infectious.
authors: Seif
authors: S
authors: Shekalaghe
authors: Mastidia
authors: M
authors: Rutaihwa
authors: Peter F
authors: PF
authors: Billingsley
authors: Mwajuma
authors: M
authors: Chemba
authors: Claudia A
authors: CA
authors: Daubenberger
authors: Eric R
authors: ER
authors: James
authors: Maximillian
authors: M
authors: Mpina
authors: Omar
authors: O
authors: Ali Juma
authors: Tobias
authors: T
authors: Schindler
authors: Eric
authors: E
authors: Huber
authors: Anusha
authors: A
authors: Gunasekera
authors: Anita
authors: A
authors: Manoj
authors: Beatus
authors: B
authors: Simon
authors: Elizabeth
authors: E
authors: Saverino
authors: L W Preston
authors: LWP
authors: Church
authors: Cornelus C
authors: CC
authors: Hermsen
authors: Robert W
authors: RW
authors: Sauerwein
authors: Christopher
authors: C
authors: Plowe
authors: Meera
authors: M
authors: Venkatesan
authors: Philip
authors: P
authors: Sasi
authors: Omar
authors: O
authors: Lweno
authors: Paul
authors: P
authors: Mutani
authors: Ali
authors: A
authors: Hamad
authors: Ali
authors: A
authors: Mohammed
authors: Alwisa
authors: A
authors: Urassa
authors: Tutu
authors: T
authors: Mzee
authors: Debbie
authors: D
authors: Padilla
authors: Adam
authors: A
authors: Ruben
authors: B Kim Lee
authors: BKL
authors: Sim
authors: Marcel
authors: M
authors: Tanner
authors: Salim
authors: S
authors: Abdulla
authors: Stephen L
authors: SL
authors: Hoffman
mesh_terms: D000328:Adult; D000818:Animals; D015925:Cryopreservation; D004311:Double-Blind Method; D005838:Genotype; D006801:Humans; D007271:Injections, Intradermal; D017780:Malaria Vaccines / Q000008:administration & dosage* / Q000009:adverse effects; D016778:Malaria, Falciparum / Q000469:parasitology / Q000517:prevention & control*; D008297:Male; D018512:Parasitemia; D010963:Plasmodium falciparum / Q000145:classification / Q000235:genetics / Q000276:immunology*; D034101:Sporozoites / Q000276:immunology*; D013636:Tanzania; D055815:Young Adult; D017085:alpha-Thalassemia / Q000235:genetics
chemical_list: D017780:Malaria Vaccines