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In this work the influence of oxygen injection on the inactivation of microbiological indicators during reclaimed wastewater transportation was studied. Experiments were carried out in a completely filled gravity pipe (62 km long), at two different periods of the year and with three different oxygen doses (7, 15 and 30 mg L−1). Microbiological parameters studied were faecal coliforms, Escherichia coli, enterococci and somatic coliphages. As a consequence of the oxygen injection, a significant inactivation of the microbiological parameters was observed during the aerobic stretch of the pipe. Later, once the oxygen had been consumed, inactivation stopped and even a slight regrowth of the microbial population took place. Inactivations were within the range of 0.6–1.0 log10 units, in most cases. No significant differences between inactivations for the different microbiological parameters were found, except for the somatic coliphages. A relationship between the inactivation degree and oxygen dose and organic matter content was observed. The biofilm played an important role in the inactivation process. The injection of oxygen contributes to improving the microbiological quality of reclaimed wastewater during its transport by pipelines, helping to diminish the subsequent on-site disinfection requirements. [ABSTRACT FROM PUBLISHER]

The article examines Cryptosporidium which includes important enteric pathogens in patients with diarrhea in Tenerife, Canary Islands, Spain. The genus Cryptosporidium includes important enteric pathogens that cause diarrheal illness in humans and other mammals. Although such pathogens only cause an illness that it is generally acute, mild and self-limiting in immunocompetent adults, infected immunocompromised individuals can develop chronic and potentially life-threatening diarrhoea. Information about the diagnosis of Cryptosporidium infection in clinical microbiology is discussed.