Helicobacter pylori

Hello everyone, my name is Dr. Sarah Fouch. Within this recording, we are going to think about an organism called Helicobacter pylori. We will consider the symptoms and conditions that this organism is associated with, and the virulence factors that it can produce to make it a successful pathogen.

Now, when we are considering Helicobacter pylori, we've known about this organism since around 1983. It was isolated in patients suffering from gastritis. Gastritis is an inflammation of the stomach lining that can cause long-term problems for patients. When we think about the number of individuals that have Helicobacter infections, actually it's very low in childhood, and children don't tend to suffer from Helicobacter. But in comparison, it increases when we go into adulthood. Actually, about 50% of us will have suffered from a Helicobacter pylori infection. This is also different in developing countries. We can actually see by the numbers there that in developing countries, in adulthood, actually, infections can increase to 85% to 95% of the adult population. We can see that we have a very variable prevalence. When we think about patients with gastric ulcers, 70% to 100% of these patients have had or have a Helicobacter pylori infection. In 1975, Marshall and Warren linked Helicobacter pylori with gastric ulcers, and nobody believed them. They said, "We're finding these spiral organisms in the linings of individual stomachs and these individuals are sufferers from gastric ulcers". Unfortunately, looking at the data, there was intermittent detection. Marshall and Warren really wanted to prove that Helicobacter pylori was the cause of these gastric ulcers. What happened in the end? In order to prove his theory, Marshall took the step of drinking a culture of Helicobacter pylori. Several days later, he had nausea and vomiting, and a little while later, he had an endoscopy and he revealed gastritis with Helicobacter pylori. A little while on, he went on to experience a gastric ulcer. This is an extreme way to prove a point, but obviously, Marshall really wanted to show that Helicobacter pylori was associated with gastritis and also gastric ulcers. Humans are the main reservoir of infection here, and it's not a nice thing to think about. But Helicobacter pylori is also associated with gastric cancers as well, so gastric lymphomas are important. How do we transmit Helicobacter pylori? Well, this can be through the oral-to-oral route and also the faecal-to-oral route. We tend to transmit this infection between ourselves.