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A microbe that causes malaria tricks mosquitos into helping it spread, a new study finds. The microbe is a parasite that leaves a chemical behind in the blood of the people or other animals that it infects. Mosquitoes are drawn to scent of blood hosting this chemical. It entices them to slurp up some of the infected meal. Then voila! The parasites get airlifted from their old host to new ones. And so malaria spreads.

Why are millions of people allergic to peanuts or pollen, but hardly anyone seems to have a reaction to rice or raisins? Because only some of these things carry molecules similar to those found in parasites that send our immune systems into hyperdrive, according to a new study. The advance could help researchers predict what other foods might cause allergies.

This case study follows two beginning undergraduate researchers on a quest for a summer research project related to food web ecology. While writing their research proposal, the students receive feedback indicating that they have neglected an entire group of organisms from their food web-parasites, which leads them to a scientific research paper discussing how these organisms have been overlooked by scientists studying food webs, the challenges involved with including parasites in food webs, and the contributions parasites ultimately make to food webs. An integrated activity in which students visualize the food web using images of organisms and answer questions about species interactions provides opportunities to examine key concepts such as omnivory, ontogenetic diet changes, trophic levels, complex life cycles, and taxonomic aggregation. This case study was originally written for an undergraduate general ecology course, but could easily be adapted to undergraduate general biology courses covering community ecology or specific courses in invertebrate zoology, parasitology, or disease ecology. The teaching notes also discuss how the included code for R statistical computing software can be used to extend the case study in a more quantitative direction if desired.

Symbiotic relationships are interactions between species that live closely with each other and are commonly separated into three types: parasitism, mutualism, and commensalism. Students are often under the impression that these types are distinct and mutually exclusive, but on closer examination some interactions appear to be at times mutualistic, at other times parasitic. Is it perhaps better to think of mutualism and parasitism as two ends of a sliding scale, with commensalism in the middle? In this case study, students consider this question by examining what is often considered to be a classic example of mutualism existing between oxpecker birds and African savanna large mammals. After students examine data from a research study on oxpecker behavior, they then apply a more nuanced understanding of species interactions to a set of additional scenarios. The learning objectives for the case align with the Four-Dimensional Ecology Education Framework. The case was written for an upper-level undergraduate ecology course, but could easily be adapted for an introductory biology course.

In this case study, students follow "Mr. Okoro" as he makes the long journey with his sick daughter "Ada" to seek medical attention at the nearest clinic in Enugu, Nigeria. It is the rainy season, and "Dr. Fabian" from the Division of Parasitic Diseases and Malaria has been called in to investigate a suspected outbreak of malaria. Students learn about the circumstances in Ada's background that may have led to her illness, and then adopt the perspective of Dr. Fabian as she investigates the outbreak. They consider the epidemiological triangle, the different stages of the Plasmodium parasite lifecycle and how it leads to malaria, and evaluate the broader societal factors and future implications of malaria in Sub-Saharan Africa. The case was designed for upper-level global health, public health, and human biology courses, but could also be adapted for general biology, health studies, infectious disease, and epidemiology courses.

An MRI scan showed a cluster of what appeared to be lesions in his brain, but specialists were baffled as to the cause. And they were more surprised to find that the lesions kept moving. Brain scans over the next four years showed that the anomaly had travelled at least 5cm through the tissue.

8:19 video The Nobel Prize in Physiology or Medicine 2015 goes to William Campbell & Satoshi Ōmura "for their discoveries concerning a novel therapy against infections caused by roundworm parasites" and Youyou Tu "for her discoveries concerning a novel therapy against Malaria".

A deadly disease known as African sleeping sickness has puzzled doctors for decades. It would disappear from villages without a trace, only to re-emerge weeks or months later with no known cause. Frustrated health officials wondered how sleeping sickness could persist when not a single villager or animal-the disease's only carriers-tested positive for the insect-borne parasite that causes it. Now, scientists may have an answer at last: They've discovered the disease was hiding in plain sight this whole time, living in and even transmitting via human skin.

In recent years, Claverie and his colleagues have discovered a host of giant viruses, which are as big as bacteria but lack characteristic cellular machinery and metabolism of those microorganisms. At least one family of these viruses likely evolved from single-celled parasites after losing essential genes, although the origins of other giant viruses remain a mystery, Claverie said.

The parasitic and apparently tasty honey fungus not only divides opinions; it is also widely seen as the largest living organism on Earth. More precisely, a specific honey fungus measuring 2.4 miles (3.8 km) across in the Blue Mountains in Oregon is thought to be the largest living organism on Earth.

If the lab technique works in the field, it could offer a new way of stopping the biting insects from spreading malaria to humans, they say. The scientists put a new "resistance" gene into the mosquito's own DNA, using a gene editing method called Crispr. And when the GM mosquitoes mated - their offspring inherited the same resistance, PNAS journal reports. In theory, if these mosquitoes bite people, they should not be able to pass on the parasite that causes malaria.

The war against malaria has a new ally: a controversial technology for spreading genes throughout a population of animals. Researchers report today that they have harnessed a so-called gene drive to efficiently endow mosquitoes with genes that should make them immune to the malaria parasite-and unable to spread it. On its own, gene drive won't get rid of malaria, but if successfully applied in the wild the method could help wipe out the disease, at least in some corners of the world. The approach "can bring us to zero [cases]," says Nora Besansky, a geneticist at the University of Notre Dame in South Bend, Indiana, who specializes in malaria-carrying mosquitoes. "The mosquitos do their own work [and] reach places we can't afford to go or get to."

Hilary Brown is a PhD student, working in the infection genomics group at the Wellcome Trust Sanger Institute. In this film he describes how to work safely in the lab with bacteria from the human gut including culturing them on agar plates and extracting the DNA for genome sequencing. The infection genomics programme uses a variety of different research approaches to study the biology and evolution of disease-causing organisms such as viruses, bacteria and parasites and understand how they cause disease in humans and other animals.

American Museum of Natural History Explore the natural world with Science Bulletins; our documentary Feature Stories, Data Visualizations, and News updates focus on recent discoveries and new technologies in astrophysics, Earth science, biodiversity, and human health and evolution.

4:17 video malaria life cycle

Brain-eating amoebas (Naegleria fowleri) are found in warm freshwater pools around the world, feeding on bacteria. If someone swims in one of these pools and gets water up their nose, the amoeba heads for the brain in search of a meal. Once there, it starts to destroy tissue by ingesting cells and releasing proteins that make other cells disintegrate.

Researchers tested pairs of identical and non-identical twins to see how attractive they were to mosquitoes. Identical twins were more likely to have similar levels of attractiveness - suggesting shared genetic factors were at play. The "intriguing" results must now be assessed in larger trials, experts say. Researchers have long tried to understand what drives mosquitoes to bite certain people more than others. Recent work shows the insects may be lured to their victims by body odour.

An Indiana woman undergoing surgery in Los Angeles to remove a tumor experienced a twist worthy of a sci-fi plot when doctors discovered an embryonic twin in her brain.

In 2015 the bees are still dying in masses. Which at first seems not very important until you realize that one third of all food humans consume would disappear with them. Millions could starve. The foes bees face are truly horrifying - some are a direct consequence of human greed. We need to help our small buzzing friends or we will face extremely unpleasant consequences.