Analysis of local drinking water for fecal contamination in Solu-Khumbu / Mt. Everest region, Nepal.

BACKGROUND: To evaluate the drinking water quality in the popular trekking area of Solu-Khumbu Mt. Everest region as a possible source for the high incidence of diarrhea. MATERIAL AND METHODS: Drinking water samples (n = 80) were collected from whatever primary source the locals/tourists used at altitudes 2,608 to 5,180m; and where possible, also from inside households. Samples were analyzed for fecal contamination using the DelAgua Dual Incubator at 37 °C and 44 °C to detect the total and thermotolerant coliform bacteria. The pH, temperature, turbidity, smell, and taste were also registered. RESULTS: No thermotolerant bacteria were found but a significant number of specimens contained many colony forming units (CFU) of total coliform bacteria. Household specimens were more often contaminated compared to the water from the primary source. CONCLUSION: Data indicate a significant secondary contamination when water was handled and stored in unhygienic containers. Health education programs on water hygiene, sanitation, and the safe handling and storage of water needs improvement. It is strongly recommended that drinking water is disinfected using filter systems, UV-light dispensers or halogens (e.g. chlorine), or a combination of two methods. Although cooking is a common disinfection method here, fuel is scarce. Water was generally safer when collected directly from the primary source in a clean container than from a lodge.

Variables Influencing the Pressure and Volume of the Pulmonary Circulation as Risk Factors for Developing High Altitude Pulmonary Edema (HAPE).

BACKGROUND: At altitudes above 2500 m, the risk of developing high altitude pulmonary edema (HAPE) grows with the increases in pulmonary arterial pressure. HAPE is characterized by severe pulmonary hypertension, though the incidence and relevance of individual risk factors are not yet predictable. However, the systolic pulmonary pressure (SPAP) and peak in tricuspid regurgitation velocity (TVR) are crucial factors when diagnosing pulmonary hypertension by echocardiography. METHODS: The SPAP and TVR of 27 trekkers aged 20-65 years en route to the Solu Khumbu region of Nepal were assessed. Echocardiograph measurements were performed at Lukla (2860 m), Gorak Shep (5170 m), and the summit of Kala Patthar (5675 m). The altitude profile and the participants' characteristics were also compiled for correlation with the measured data. RESULTS: The results showed a highly significant increase in SPAP and TVR after ascending Kala Patthar. The study revealed a lower increase of SPAP and TVR in the group of older participants, although the respective initial measurements at Gorak Shep were significantly higher for this group. A similar finding occurred in those using Diamox® as prophylaxis. There was an inverse relationship between TVR and SPAP, the peripheral capillary oxygen saturation, and heart rate. CONCLUSIONS: The echocardiograph results indicated that older people are an at-risk group for developing HAPE. A conservative interpretation of the basic tactical rules for altitudes should be followed for older trekkers or trekkers with known problems of altitude acclimatization ("slow acclimatizer") as SPAP elevates with age. The prophylactic use of Acetazolamide (Diamox®) should be avoided where not necessary for acute medical reasons. Acetazolamide leads to an increase of SPAP, and this may potentially enhance the risk of developing HAPE. Arterial oxygen saturation measurements can provide an indicator for the self-assessment for the risk of developing HAPE and a rule of thumb for the altitude profile, but does not replace a HAPE diagnosis. Backpack weight, sex, workload (actual ascent speed), and pre-existing diseases were not statistically significant factors related to SPAP and TVR (p ≤ 0.05).