Innovative study on the parasites showing that these parasites have a real impact on brain function in rodents, independent of long term developmental delays; that can be observing very quickly after initial infection. This means study very likely been underestimating the impact these parasites have on the brain in both children and adults, but particularly in very young children.
But the study showing that short-term human hookworm infection; even at low levels, can cause rapid, acute and measurable cognitive impairments in spatial memory among a mammalian animal model. Hookworms are a species of parasites that live in the small intestine and infect via the skin, circulation and lung. Hookworm infection is most common in the developing world where proper hygiene and sanitation are a challenge.
Real impact on brain function
Long-term infection is known to cause severe developmental and cognitive impairments. The Centers for Disease Control and Prevention estimates that infection occurs in 576 million to 740 million people worldwide. Hookworm infection is one of the leading causes of anemia, stunted growth and malnutrition. Three species of hookworms can infect humans. People most commonly infecting typically reside in poverty stricking areas with poor sanitation and are exposing to the worm through contaminating soil or food.
The worms can live in the small intestine for a few years typically, but for as long as 10 years, consuming blood and robbing their hosts of iron and protein, interfering with absorption of critical nutrients, and suppressing the immune system. Infection can lead to chronic anemia, as well as permanently stunt the physical and intellectual development of infected children.
Public health efforts
Common in the American south 100 years ago, hookworms were virtually eradicating in the United States through improvements in sanitation; and public health efforts during the early part of the 20th century. According to Aroian, prior research into this area has been hindering by an assumption; that cognitive impairments happen due to developmental delaying and malnutrition caused by long-term infection.
While it is clear that heavy infection loads over time do impact development and brain function; it is less clear if infection can cause acute cognition impairment independent of stunting. To mimic acute infection, rodents were infecting with juvenile Ancylostoma ceylanicum; a species of hookworm that can infect humans, dogs, cats and rodents. Aroian and colleagues completing a series of tests designing to assess; whether the animal could recognize a new object placing in its environment or an object; that had been moving from one place to another within its environment within 17 to 22 days of infection.