Molecular characterization and antibiotic susceptibility pattern of caprine Shiga toxin producing-Escherichia coli [STEC] isolates from India

The present study was conducted to detect the occurrence, serotype, genotype, phylogenetic relationship and antimicrobial resistance pattern of STEC from healthy goats of West Bengal, India. From the 125 faecal samples collected from healthy goats, 245 isolates were identified as Escherichia coli. The E. coli harbouring any gene for Shiga toxins [stx[1]/stx[2]] was detected in 36 [14.7%] of the 245 E. coli isolates. These STEC strains belonged to 22 different serogroups [O2, O5, O20, O21, O22, O25, O41, O44, O45, O60, O71, O76, O84, O85, O87, O91, O103, O112, O113, O120, O156, and O158] and three were untypeable. The stx[1] and stx[2] was detected in 26 [72.2%] and 21 [58.3%] of Shiga toxin producing-E. coli [STEC] isolates, respectively. Further, E. coli harbouring eaeA only [Enteropathogenic E. coli] and ehxA was detected in 22 [61.1%] and 28 [77.7%] isolates, respectively. Whereas the saa was present in 8 [22.2%] E. coli isolates. The subtyping of the 26 E. coli strains possessing stx[1] showed that 73.% [19/26] of these isolates were positive for stx[1C] subtype. Of the 21 isolates with the stx[2] gene, 42.8% [9/21] were positive for stx[2C], and 38.1% [8/21] were positive for stx[2d] gene. The phylogenetic analysis of STEC strains after RAPD reveals eight major clusters. However, no serogroup specific cluster was observed. Resistance was observed most frequently to erythromycin [80.5%], amikacin [52.7%], cephalothin [50%], kanamycin [41.6%], neomycin [36.1%] and gentamycin [36.1%] and less frequently to norfloxacin [2.7%], enrofloxacin [2.7%], and ciprofloxacin [2.7%]. Multidrug resistance was observed in eleven STEC isolates

Estimation of mortality due to AIDS--a review.

HIV/AIDS has emerged as a major public health problem since its recognition as an emerging disease a couple of decades ago. While detection of HIV/AIDS cases remains a problem, ascertainment of AIDS deaths has emerged as a bigger challenge and concern. Despite a plethora of literature focusing on the methods to estimate AIDS deaths, none seems to be fulfilling the requirements for universal acceptance. In this paper, we give a systematic review of various methods used by experts to have a reliable estimate of the number of deaths due to AIDS. Initial assessments were derived from morgue based estimates in Africa which showed that AIDS was a leading cause of death. Its impact on demography was noticed in some of the studies conducted wherein age and sex specific mortality rates, standardized mortality ratios, potential years of life lost and decrease in life expectancy were calculated. "Excess mortality factor" as observed in 1980s and 1990s also indicated the approximate number of AIDS deaths. Besides, orphan hood method and verbal autopsy technique too, emerged as reliable means to identify mortality due to AIDS. Some indirect methods like estimation of deaths due to opportunistic infections like tuberculosis could also be a good indicator. The paper reviews the merits and possible biases encountered with each of the methods.