Sentinel Hospital-Based Surveillance for Assessment of Burden of Rotavirus Gastroenteritis in Children in Pakistan

Objectives

To determine the burden and molecular epidemiology of rotavirus gastroenteritis in children hospitalized with severe acute watery diarrhea in Pakistan prior to introduction of rotavirus vaccine.

Methods

A cross-sectional study was carried out over a period of two years from 2006 – 2008 at five sentinel hospitals in the cities of Karachi, Lahore, Rawalpindi, and Peshawar. Stool samples collected from children under five years of age hospitalized with severe acute watery diarrhea were tested for rotavirus antigen via enzyme immunoassay (EIA) (IDEA REF K6020 Oxoid Ltd (Ely), Cambridge, United Kingdom). A subset of EIA positive stool samples were further processed for genotyping.

Results

6679 children were enrolled and stool specimens of 2039 (30.5%) were positive for rotavirus. Rotavirus positivity ranged from 16.3% to 39.4% in the 5 hospitals with highest positivity in Lahore. 1241 (61%) of all rotavirus cases were in infants under one year of age. Among the strains examined for G-serotypes, the occurrence of G1, G2, G9 and G4 strains was found to be 28%, 24%, 14% and 13%, respectively. Among P-types, the most commonly occurring strains were P6 (31.5%) followed by P8 (20%) and P4 (12%). Prevalent rotavirus genotype in hospitalized children of severe diarrhea were G1P[8] 11.6% (69/593), followed by G2P[4] 10.4% (62/593), and G4P[6] 10.1% (60/593).

Conclusions

Approximately one third of children hospitalized with severe gastroenteritis in urban centers in Pakistan have rotavirus. Introduction of rotavirus vaccine in Pakistan''s national immunization program could prevent many severe episodes and diarrheal deaths.     

Limited hybridization between introduced and Critically Endangered indigenous tilapia fishes in northern Tanzania

Hydrobiologia - Hybridization between introduced and indigenous species can lead to loss of unique genetic resources and precipitate extinction. In Tanzania, the Nile tilapia (Oreochromis...     

Subclass specificity of autoantibodies against myosin in patients with idiopathic dilated cardiomyopathy: pro-inflammatory antibodies in DCM patients.

Detection of antimyosin antibodies in non-inflammatory cardiac disease undermines their disease specificity as a sensitive marker of damage in dilated cardiomyopathy (DCM) patients. Antibody subclass specificity could provide a more sensitive marker of disease and possibly discriminate the humoral autoimmune responses in different cardiac diseases. Frequency and reactivity of autoantibodies against alpha- and beta-isoforms of myosin heavy chain (mhc) were evaluated by ELISA for IgG, IgM, and subclasses IgG1, IgG2, and IgG3 in patients with DCM (NYHA III/IV, n = 82), end stage ischemic heart disease (E-IHD: NYHA III/IV, n = 62), mild ischemic heart disease (NYHA I/II, n = 27), and controls (n = 54). Autoantibodies against atrial and ventricular myosin were raised in heart failure patients compared to mild-IHD and controls but with different antigen affinities. Reactivity in E-IHD was significantly raised against (ventricular) beta-mhc compared with only mild-IHD patients, suggesting a relative increase in ventricular specific antibodies in IHD patients with a higher NYHA class. IgG subclass analysis for IgG1, IgG2, and IgG3 against alpha- and beta-mhc showed statistically raised levels of IgG3 only in DCM patients and a significantly higher reactivity of IgG2 in heart failure patients versus controls. The results demonstrate immunological heterogeneity of antimyosin antibodies developed in different clinical entities. Pro-inflammatory characteristics of IgG3 antibodies in a select group of patients with DCM may contribute to autoimmune mechanisms of injury in these patients.