Acute P. falciparum malaria is associated with loss of in vitro T cell responsiveness to antigenic stimulation, and with high plasma levels of soluble interleukin 2 receptor (IL 2R). In the present study peripheral T cells from acute P. falciparum malaria patients from a malaria-endemic area of Sudan were analyzed for expression of cell surface antigens associated with T lymphocyte adhesion, activation and maturation. The results were compared to results from T cells obtained from the same donors either before the attack, or during convalescence. Most donors showed a remarkable loss of T cells with high expression of the surface marker LFA-1 (CD11a/CD18) during the clinical episode, in addition to the functional changes described above. Two donors that did not show phenotypic changes were furthermore characterized by having an unabated proliferative response and normal plasma IL 2R levels. All peripheral CD3+ T lymphocytes expressed LFA-1, which had a clearly bimodal distribution on these cells. The T cell subpopulation having high LFA-1 expression (LFA-1++) was composed of both memory and unprimed T cells, according to their expression of CD45RA and CD45R0. Analysis of expression of membrane-bound IL 2R (CD25) and ICAM-1 (CD54) did not reveal in vivo activated T cells in the peripheral blood of the patients. Taken together, these data suggest that circulating T cells recognizing parasite antigens are temporarily withdrawn from peripheral circulation during P. falciparum malaria.

Rickettsiosis and theileriosis can cause mortalities in camel populations. This study was conducted to achieve 2 objectives: (1) to detect the presence of SFG Rickettsia sp. and Theileria sp. in Hyalomma dromedarii Koch, 1844 (Acari: Ixodidae) ticks and (2) to determine their prevalence in the tick population on the sampled camel farms in Al-Ain, United Arab Emirates (UAE). Camel ticks (H. dromedarii) were collected from a total of 625 one-humped camels (Camelus dromedarius) in 22 sampling locations in Al-Ain, UAE. Tick samples were analyzed by Polymerase Chain Reaction (PCR). An SFG Rickettsia sp., which was 99% similar to Candidatus 'Rickettsia andeanae' and Rickettsia endosymbionts, was detected only in 2011 and its prevalence in the sampled ticks was 1.12%, while Theileria annulata was detected in both years with a prevalence of 2.3% and 1.60%, respectively. Additionally, T. annulata was present in all of the sampling zones (east, west, north, and south) of the study area, whereas SFG Rickettsia sp. was limited to 2 zones only (east and south). The geographic distributions of SFG Rickettsia sp. and T. annulata showed no overlap throughout the entire study area except in one location in which both of the disease agents were present. This study is the first published record on the presence of SFG Rickettsia sp. and T. annulata in camel ticks in the UAE. In addition, the current study should serve as a foundation for more studies leading to a better understanding of the reservoir potential of camels and the risk posed by these 2 disease agents to camels and other livestock.

Compared to men the CD seroprevalence among women was remarkably higher. The CD association with women and chronic anemia is of importance from a public health perspective.

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