Impact of transmission intensity and age on Plasmodium falciparum density and associated fever

Implications for malaria vaccine trial design

C. Beadle, P. D. McElroy, C. N. Oster, John C Beier, A. J. Oloo, F. K. Onyango, D. K. Chumo, J. D. Bales, J. A. Sherwood, S. L. Hoffman

Research output: Contribution to journalArticle

47 Citations (Scopus)

Abstract

To facilitate design of vaccine trials, malaria was studied in 6-month- to 6-year-old Kenyans during high (HI) and low intensity transmission seasons. During 84 days after cure, exposure to infected mosquitoes was 9-fold greater in the HI group, yet incidence of P. falciparum infection was increased only 2-fold, with no age effect. The density of recurrent P. falciparum was 14- fold greater in the HI group, and there was a striking association between age and parasitemia ≥5000/μL. Fever was the only clinical manifestation attributable to parasitemia and only when the parasite density was ≥5000/μL. Sixty-four percent of children with ≥20,000 parasites/μL versus 10% with 1-4999/μL were febrile when parasitemic. Recurrent P. falciparum infection as a vaccine trial end point can be studied year-round among children ≥6 years in western Kenya. However, high-grade parasitemia (≥5000 or 20,000/μL) with or without elevated temperature will be optimally studied in the high transmission season among children <2 years.

Original languageEnglish
Pages (from-to)1047-1054
Number of pages8
JournalJournal of Infectious Diseases
Volume172
Issue number4
StatePublished - Jan 1 1995
Externally publishedYes

Fingerprint

Malaria Vaccines
Parasitemia
Plasmodium falciparum
Fever
Malaria
Parasites
Kenya
Culicidae
Vaccines
Temperature
Incidence

ASJC Scopus subject areas

  • Immunology
  • Public Health, Environmental and Occupational Health

Cite this

Impact of transmission intensity and age on Plasmodium falciparum density and associated fever : Implications for malaria vaccine trial design. / Beadle, C.; McElroy, P. D.; Oster, C. N.; Beier, John C; Oloo, A. J.; Onyango, F. K.; Chumo, D. K.; Bales, J. D.; Sherwood, J. A.; Hoffman, S. L.

In: Journal of Infectious Diseases, Vol. 172, No. 4, 01.01.1995, p. 1047-1054.

Research output: Contribution to journalArticle

Beadle, C, McElroy, PD, Oster, CN, Beier, JC, Oloo, AJ, Onyango, FK, Chumo, DK, Bales, JD, Sherwood, JA & Hoffman, SL 1995, 'Impact of transmission intensity and age on Plasmodium falciparum density and associated fever: Implications for malaria vaccine trial design', Journal of Infectious Diseases, vol. 172, no. 4, pp. 1047-1054.
Beadle, C. ; McElroy, P. D. ; Oster, C. N. ; Beier, John C ; Oloo, A. J. ; Onyango, F. K. ; Chumo, D. K. ; Bales, J. D. ; Sherwood, J. A. ; Hoffman, S. L. / Impact of transmission intensity and age on Plasmodium falciparum density and associated fever : Implications for malaria vaccine trial design. In: Journal of Infectious Diseases. 1995 ; Vol. 172, No. 4. pp. 1047-1054.
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