Comparative Genomic Analysis of Meningitis- and Bacteremia-Causing Pneumococci Identifies a Common Core Genome.

Streptococcus pneumoniae is a nasopharyngeal commensal that occasionally invades normally sterile sites to cause bloodstream infection and meningitis. Although the pneumococcal population structure and evolutionary genetics are well defined, it is not clear whether pneumococci that cause meningitis are genetically distinct from those that do not. Here, we used whole-genome sequencing of 140 isolates of S. pneumoniae recovered from bloodstream infection (n = 70) and meningitis (n = 70) to compare their genetic contents. By fitting a double-exponential decaying-function model, we show that these isolates share a core of 1,427 genes (95% confidence interval [CI], 1,425 to 1,435 genes) and that there is no difference in the core genome or accessory gene content from these disease manifestations. Gene presence/absence alone therefore does not explain the virulence behavior of pneumococci that reach the meninges. Our analysis, however, supports the requirement of a range of previously described virulence factors and vaccine candidates for both meningitis- and bacteremia-causing pneumococci. This high-resolution view suggests that, despite considerable competency for genetic exchange, all pneumococci are under considerable pressure to retain key components advantageous for colonization and transmission and that these components are essential for access to and survival in sterile sites.

Profiles of blood and blood component transfusion recipients in Zimbabwe.

BACKGROUND: There are limited published data on the characteristics of blood transfusion recipients in sub-Saharan Africa. This study describes the demographic characteristics of blood transfusion recipients and patterns of blood and blood component use in Zimbabwe. MATERIALS AND METHODS: Data on the characteristics of the blood transfusion recipients (age, sex, blood group), blood components received (type, quantity), discharge diagnoses and outcomes following transfusion (discharge status, duration of stay in hospital), were retrospectively collected from four major hospitals for the period from January 1, 2012 to December 31, 2012. Diagnoses were grouped into broad categories according to the disease headings of the International Classification of Diseases (ICD-10). Surgical procedures were grouped into broad categories according to organ system using ICD-9. RESULTS: Most of the 1,793 transfusion recipients studied were female (63.2%) and in the reproductive age group, i.e. 15-49 years (65.3%). The median age of the recipients was 33 years (range, 0-93). The majority of these recipients (n=1,642; 91.6%) received a red blood cell transfusion. The majority of the patients were diagnosed with conditions related to pregnancy and childbirth (22.3%), and diseases of blood and blood-forming organs (17.7%). The median time spent in hospital was 8 days (range, 0-214) and in-hospital mortality was 15.4%. DISCUSSION: Our sample of blood transfusion recipients were fairly young and most of them received red blood cell transfusions. The majority of patients in the reproductive age group received blood transfusions for pregnancy and childbirth-related diagnoses.

The impact of rapid malaria diagnostic tests upon anti-malarial sales in community pharmacies in Gwagwalada, Nigeria.

BACKGROUND: Rapid diagnostics tests for malaria (RDT) have become established as a practical solution to the challenges of parasitological confirmation of malaria before treatment in the public sector. However, little is known of their impact in private health sector facilities, such as pharmacies and drug shops. This study aimed to assess the incidence of malaria among unwell patients seeking anti-malarial treatment in two community pharmacies in Nigeria and measure the impact RDTs have on anti-malarial sales. METHODS: This was a comparison study of two pharmacies located in the suburbs of Gwagwalada, in the Federal Capital Territory of Nigeria, between May and July 2012. In the intervention arm, patients seeking to purchase anti-malarials had an RDT performed before treatment while the control pharmacy continued normal routine practice. RESULTS: A total of 1,226 participants were enrolled into the study. The incidence of malaria in the intervention arm (n = 619) was 13.6% and adolescent participants had a statistically significant higher incidence (26.0%) compared to adults (11.9%) (P = 0.001). A history of fever in the last 48 hours was associated with a statistically significant higher incidence of malaria (28.3%) (P < 0.001). Having a RDT test reduced the chance of purchasing an anti-malarial by 42% (95% CI: 38%-46%) compared to not having a test. 51.6% (276) of the study participants with a RDT negative result still purchased anti-malarials, especially if anti-malarials had been recommended by a health professional (58.9%) compared to self-referral (44.2%) (P = 0.001). Patients with RDT negative results were also more likely to purchase an anti-malarial if there was a reported malaria positive laboratory test prior to presentation (66.2%; P = 0.007), a history of fever in the last 48 hours (60.5%; P = 0.027), and primary school education or less (69.4%; P = 0.009). After adjusting for age group and gender differences, having at least a secondary school education reduced the chance of buying an anti-malarial (OR 0.504 (95% CI: 0.256-0.993)) compared to having primary education or lower. CONCLUSION: The study highlights the enormous potential for improving appropriate prescription of anti-malarials in pharmacies and preventing unnecessary use of artemisinin combination therapy (ACT).

The use of insecticide-treated nets for reducing malaria morbidity among children aged 6-59 months, in an area of high malaria transmission in central Côte d'Ivoire.

BACKGROUND: Long-lasting insecticidal nets (LLINs) are an important tool for controlling malaria. Much attention has been devoted to determine both the effect of LLINs on the reduction of Plasmodium infection rate and on clinically-confirmed malaria cases in sub-Saharan Africa. We carried out an epidemiological study to investigate whether LLINs impact on Plasmodium prevalence rate and the proportion of clinically-confirmed malaria cases, in five villages in the district of Toumodi, central Côte d'Ivoire. METHODS: From April 2007 to November 2008, a community-based malaria control programme was implemented in the study villages, which involved large-scale distribution of LLINs, and training and sensitization activities within the community. We determined the effect of this programme on Plasmodium prevalence rate, clinically-confirmed malaria cases and proportion of high parasitaemia rates in children aged 6-59 months through a series of cross-sectional surveys starting in April 2007 and repeated once every 6 months. RESULTS: We observed a significant decrease in the mean P. falciparum prevalence rate from April 2007 to April 2008 (p = 0.029). An opposite trend was observed from November 2007 to November 2008 when P. falciparum prevalence rate increased significantly (p = 0.003). Highly significant decreases in the proportions of clinical malaria cases were observed between April 2007 and April 2008 (p < 0.001), and between November 2007 and November 2008 (p = 0.001). CONCLUSIONS: Large-scale distribution of LLINs, accompanied by training and sensitization activities, significantly reduced Plasmodium prevalence rates among young children in the first year of the project, whereas overall clinical malaria rates dropped over the entire 18-month project period. A decrease in community motivation to sleep under bed nets, perhaps along with changing patterns of malaria transmission, might explain the observed increase in the Plasmodium prevalence rate between November 2007 and November 2008.