Naslov
Decreased Growth Rate of P. falciparum Blood Stage Parasitemia With Age in a Holoendemic Population

Autori
Pinkevych, Mykola ; Petravic, Janka ; Chelimo, Kiprotich ; Vulule, John ; Kazura, James W. ; Moormann, Ann M. ; Davenport, Miles P.

Izvornik
The Journal of Infectious Diseases (0022-1899) 209 (2013), 7; 1136-1143

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Malaria ; Plasmodium falciparum ; blood stage ; immunity ; mathematical modeling

Sažetak
In malaria holoendemic settings, decreased parasitemia and clinical disease is associated with age and cumula- tive exposure. The relative contribution of acquired immunity against various stages of the parasite life cycle is not well understood. In particular, it is not known whether changes in infection dynamics can be best explained by decreasing rates of infection, or by decreased growth rates of parasites in blood. Here, we analyze the dynam- ics of Plasmodium falciparum infection after treatment in a cohort of 197 healthy study participants of differ- ent ages. We use both polymerase chain reaction (PCR) and microscopy detection of parasitemia in order to understand parasite growth rates and infection rates over time. The more sensitive PCR assay detects parasites earlier than microscopy, and demonstrates a higher overall prevalence of infection than microscopy alone. The delay between PCR and microscopy detection is significantly longer in adults compared with children, consis- tent with slower parasite growth with age. We estimated the parasite multiplication rate from delay to PCR and microscopy detections of parasitemia. We find that both the delay between PCR and microscopy infection as well as the differing reinfection dynamics in different age groups are best explained by a slowing of parasite growth with age.

Izvorni jezik
Engleski

Znanstvena područja
Matematika, Biologija

POVEZANOST RADA