So a little background on my project...
I came to Peru to study Helicobacter Pylori, an acid producing bacteria that was only discovered in the early 1980s. H pylori is responsible for causing stomach ulcers, which can sometimes lead to other diseases such as gastric cancer. It is believed that up to 50% of the world is infected with H. pylori and of these people 30% are symptomatic. A huge amount of the infection burden is in developing countries, and even within developing countries most of the disease burden resides within lower socioeconomic districts.
In Lima H. pylori is endemic in both adults and children. In addition, Lima has an extremely high rate of gastric cancer, but the distribution of gastric cancer differs between socioeconomic areas with the 3 districts with the highest rates of gastric cancer being in some of the lowest socioeconomic districts and the 2 districts with the lowest rates being 2 of the higher socioeconomic districts. Because H. pylori and gastric cancer are correlated it is possible that there is a community-acquired source of H. pylori in these lower socioeconomic districts that may lead to the gastric cancer (and stomach ulcers). We hypothesize that people are acquiring H. pylori through a community water source.
So on to what I will actually be doing here... While we are here we will be splitting our time between Hospital Cayetano Heredia and DIGESA (where I visited yesterday). At the hospital we will screen for patients infected with H. pylori using a questionnaire that asks about stomach ulcer symptoms. A second questionnaire will also be administered that assesses risk factors, such as where the patient gets his or her water from, living conditions, etc. Once a patient is identified an endoscopy will be performed to take a sample to test for specific strains of H. pylori. Then, we will hopefully be able to go to the patient's water source, and with the help of DIGESA, take 2 liters of water and a biofilm sample to test for H. pylori. Some of the lab work will be done at DIGESA (this is what we learned to do yesterday) and some of the sample will be shipped back to a lab at the School of Public Health at U of M for DNA strain analysis. Culturing the water samples will be the hard part of the experiment. It is believed that H. pylori exists in a different form in humans and in the environment. There are standard protocols to culture H. pylori from stomach mucosa, but it has been very hard to culture H. pylori from water samples - even water samples that have had H. pylori added directly to them. We will definitely have our work cut out for us!
Today we were given a tour of the water treatment system for Lima. With us was a man from England. Thank goodness he was there, because he could translate everything that was said and ask questions. We also went to lunch with him and a director from DIGESA. He is trying to sell a new water purifying system to Latin America (also used in pools and trying to be approved for necrotic infections with diabetes). Quite the salesman...but very nice...
The water treatment plant is a huge complex with beautiful green gardens, a new modern headquarters that was all blue (how fitting for the water theme), labs to test different chemical and microbiologic aspects of water quality, and even some soccer fields. As of now this is the only water treatment plant for all of Lima - 8 million people! 82% have access to some "purified" water (no one at the plant said they would drink it) and only 20% have water uninterrupted 24 hours a day. Even our water turned off this morning just as we finished our showers. This is supposedly uncommon since we live in one of the nicest districts in Lima. It was amazing to see the river running in one side and come out almost completely dry on the other. I was also surprised that they talk about such a water shortage, but on the grounds of the water plant I saw 5 or 6 large sprinklers watering their grounds... I wonder how often they use the sprinklers...
Pollution of the water is also a major problem here. People illegally dump everything from dead horses to chemicals from unregistered and registered factories. I asked what the penalty is for illegal dumping. If chemicals from factories are found, then they take a water sample every hour to check for water. Other people will be fined and will hire companies to remove the waste they have dumped, but often these hired companies will just double back and re-dump the waste in the river!
Seeing the whole system reminded me of one of my favorite Magic School Bus books as a kid. In the book Ms. Frizzle took the kids to a water treatment plant and they moved through the whole system as raindrops being purified. The book didn't leave out anything ... even flocculation. In the book the water ended up so much cleaner! Here at the flocculation step there was still a lot of junk floating at the top of the water because the plant is putting through 20% more water than it is built for. Luckily, there is a second water treatment plant that is scheduled to open. This plant is supposed to supply the remaining 20% of people with water collected from higher up in the mountains.
We tried to go to a conference at the ministry of health about environmental health. After waiting for 2 hours it was cancelled, because the minister of health was stuck in a meeting and there was really bad traffic. Lets be honest... I wouldn't have understood anything anyway... and at least Sarah and Christina helped me practice conjugating verbs and we played some Angry Birds on Sarah's iphone.
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