Survey and Phylogenetic Analysis of Rodents and Important Rodent-Borne Zoonotic Pathogens in Gedu, Bhutan

Rodents are well-known reservoirs and vectors of many emerging and re-emerging infectious diseases, but little is known about their role in zoonotic disease transmission in Bhutan. In this study, a cross-sectional investigation of zoonotic disease pathogens in rodents was performed in Chukha district, Bhutan, where a high incidence of scrub typhus and cases of acute undifferentiated febrile illness had been reported in people during the preceding 4–6 months. Twelve rodents were trapped alive using wire-mesh traps. Following euthanasia, liver and kidney tissues were removed and tested using PCR for Orientia tsutsugamushi and other bacterial and rickettsial pathogens causing bartonellosis, borreliosis, human monocytic ehrlichiosis, human granulocytic anaplasmosis, leptospirosis, and rickettsiosis. A phylogenetic analysis was performed on all rodent species captured and pathogens detected. Four out of the 12 rodents (33.3%) tested positive by PCR for zoonotic pathogens. Anaplasma phagocytophilum, Bartonella grahamii, and B. queenslandensis were identified for the first time in Bhutan. Leptospira interrogans was also detected for the first time from rodents in Bhutan. The findings demonstrate the presence of these zoonotic pathogens in rodents in Bhutan, which may pose a risk of disease transmission to humans.

Use of the laryngeal mask for closed circuit anesthesia

We examined whether the laryngeal mask could be used effectively in 70 patients breathing spontaneously during closed-circuit anesthesia. After administration of oxygen 101 min[-1], anesthesia was induced and the laryngeal mask inserted. After 6 min of denitrogenation [3.51 min[-1] nitrous oxide and 1.51.min[-1] oxygen], the fresh-gas flow was decreased to the minimum required to maintain refilling of a ventilator bellows [Carden Ventmasta]; nitrous oxide was turned off. A vaporiser outside the breathing system was set either by observing an end-tidal agent monitor or at 3-5 times greater than the required end-tidal concentration. The total fresh gas flow, hemodynamics and respiratory variables were monitored. Several types of operations were performed and lasted 9-126 min [mean 37 min]. The average total fresh gas flow during the closed circuit period was 340 ml. min[-1] [range 200-500 ml. min[-1]]. Blood pressure, heart rate and respiration were stable throughout anesthesia and there were no major side effects attributable to the technique. We believe that closed-circuit anesthesia in patients breathing spontaneously through the laryngeal mask, as described here, can be used safely, conveniently and effectively. This technique is suitable for surgical operations of short duration