Reproductive success in Anopheles arabiensis and the M and S molecular forms of Anopheles gambiae: Do natural sporozoite infection and body size matter?

Malaria parasites stages prior to sporozoite formation are known to affect the fecundity of several species of mosquitoes in the laboratory, but little is known about this phenomenon in natural conditions especially with sporozoite-infected anophelines. The reproductive success of wild-caught Anopheles arabiensis and the M and S molecular forms of Anopheles gambiae was investigated by comparing females infected with Plasmodium falciparum sporozoites to females free of sporozoites. Association between sporozoite-infected females' body size and their egg batch size was also measured. There was no significant reduction in egg production due to sporozoite infection among wild females An. arabiensis and the M and S form of An. gambiae. The infected groups and the controls laid similar numbers of eggs. A positive association was found between body size of females infected with P. falciparum and mean egg production. Infected females of the molecular forms of An. gambiae and their sibling species An. arabiensis invest similarly in egg batch size regardless of their body size although the expected egg batch size may differ among them because of differences in their mean body size. A reduction of egg production related to infection status was not observed among females harboring sporozoites. Therefore for the gonotrophic cycles that occur once sporozoites are present, natural infection of all three vectors we studied has no or minimal effect on their densities or their reproductive outputs.     

Difference in susceptibility to malaria between two sympatric ethnic groups in Mali

We compared malaria indicators among sympatric groups to study human heterogeneities in the response to Plasmodium falciparum malaria infection. Four cross-sectional surveys and two longitudinal surveys in two sympatric ethnic groups (Dogon and Fulani) in Mali were carried out from 1998 to 2000. Spleen and parasite rates were evaluated during the cross-sectional surveys and disease incidence was assessed during longitudinal surveys. In spite of similar sociocultural factors and entomologic inoculation rates between ethnic groups, the Fulani had a significantly higher spleen enlargement rate, lower parasite rate, and were less affected by the disease than the Dogon group, whose frequency of hemoglobin C was higher than that recorded among the Fulani group. The Fulani group had significantly higher levels of IgG and IgE against crude malaria antigen than the Dogon group, suggesting a role of anti-malaria antibodies in the immune protection seen in this group.     

Predictive Factors of Infection in the First Year after Kidney Transplantation

BackgroundInfectious disease, a complication favored by immunosuppression, is the main cause of 1st-year mortality in solid organ transplantation. In renal transplant recipients (RTRs), urinary tract infection (UTI) is the most common, and the microorganisms that are isolated depend on chronology.MethodsWe present an observational study comprising 129 RTRs from January 2010 to December 2011 who were followed during the 1st year after transplantation. We analyzed occurrence of infections, predisposing factors, timing, severity, site of infection, and microorganisms.ResultsThe patients had a total of 424 infectious episodes during the 1st year (3.29 episodes/patient/year). The predominant focus was the urinary tract, with at least 1 episode in 69.8% of patients. Bacteremia was recorded in 25.6% of patients and surgical wound infection in 20.9%. Cytomegalovirus infection or disease was diagnosed in 46.5%. Severe infections occurred in 30.2%. The predominant pathogen was E. coli. There was a significant correlation between hospital stay and the number of infections (P = .000; r = 0.407) and between body mass index and hospital stay (P = .001; r = 0.282). Severe infections were more frequent in diabetics, patients with a double-J stent, and those treated with basiliximab. Patients with cytomegalovirus replication had a higher number of infections (4.1 ± 1.2 vs 2.2 ± 2; P = .000) and significantly higher annual serum creatinine (1.65 ± 0.7 vs 1.31 ± 0.3 mg/dL; P = .003).ConclusionsThe prevalence of infections in the 1st year after kidney transplantation is very high, occurring mainly in the early period, in the urinary tract, and due to E. coli. Cytomegalovirus replication is associated with a higher number of infections and higher serum creatinine at 1 year. Body mass index is a predictor of early infection and of bacteremia in the post-transplantation period. Basiliximab induction and having a double-J stent were predictors of severe infections.     

Incidence of Post-Transplantation Lymphoproliferative Disease in Andalusia (1990–2009)

BackgroundPost-transplantation lymphoproliferative disease (PTLD) is a severe complication of renal transplantation (RT) but information about its incidence and predisposing factors is diverse, varying according to geographic area and study period.MethodsWe analyzed the incidence of PTLD after all RT performed at adult transplantation centers in Andalusia from January 1, 1990 to December 31, 2009, recorded in the Andalusian Transplant Co-ordination Information System (SICATA) regional computerized database (n = 5577). We calculated the risk of PTLD using the Kaplan-Meier curve, censoring for organ failure and incidence rate per patient-year of exposure. Log-rank comparisons were made by center (n = 5), decade (1990–1999 vs 2000–2009), age group, recipient gender, hepatitis C virus (HCV) serology, transplantation number, and duration of pre-RT replacement therapy (per quartiles).ResultsWe identified 60 cases of PTLD. The pre-RT treatment time was 48.2 ± 60 months; 11.7% were retransplantations, and 10.4% had a positive HCV serology. The median post-RT time before diagnosis of PTLD was 5.98 years. At the time of the database analysis, only 11 patients (18%) were alive with a functioning transplant; 10% had returned to dialysis and 72% had died. The actuarial incidence of PTLD at 1, 5, 10, and 20 years post-RT was 0.2%, 0.5%, 1.6%, and 2.9%, respectively; the exposure rate was 14.71 PTLD/10,000 patient-years (95% confidence interval [CI], 12.3–17.1). Although the incidence tended to be higher in 1990–1999 than 2000–2009 (16.8 vs 12.1 cases/10,000 patient-years), in the actuarial study the difference was far from significant (at 7.5 years, 1.2 vs 0.8%; P = .4). Nor were there significant differences in the curves of incidence per RT center (1%–1.2% of patients) or recipient characteristics.ConclusionsThe cumulative incidence of PTLD in Andalusia in patients with a functioning kidney transplant during 1990–2009 was 2.9% at 20 years. There was no significant variation between the RT centers or over time. No associated factors were identified among the basic recipient variables studied.