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Around the world, disease-carrying mosquitoes are advancing at speed, taking viruses such as dengue and Zika, plus a host of lesser-known ills such as chikungunya and St. Louis encephalitis, into new territories from Europe to the Pacific. "The concern is that we have these species spreading everywhere. Today the focus is on Zika but they can carry many different viruses and pathogens," said Anna-Bella Failloux, head of the department that tracks mosquito viruses at France's Institut Pasteur.

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."

 In one of the first successful attempts at genetically engineering mosquitoes, HHMI researchers have altered the way the insects respond to odors, including the smell of humans and the insect repellant DEET. The research not only demonstrates that mosquitoes can be genetically altered using the latest research techniques, but paves the way to understanding why the insect is so attracted to humans, and how to block that attraction. "The time has come now to do genetics in these important disease-vector insects.

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.

Everyone hates mosquitos. Besides the annoying buzzing and biting, mosquito-borne diseases like malaria kill over a million people each year (plus horses, dogs and cats). And over the past 100 million years, they've gotten good at their job -- sucking up to three times their weight in blood, totally undetected. So shouldn't we just get rid of them? Rose Eveleth shares why scientists aren't sure.

Malaria has long been a problem in Mali. But in 2006, the situation got worse: a malaria-carrying mosquito species named Anopheles coluzzii became increasingly resistant to common insecticides. Scientists searched for an explanation in its genes. Somehow, the species had acquired mutations that were previously only found in another species, Anopheles gambiae - despite the fact that these two species didn't usually mate with each other, and that their hybrids tended to die without producing offspring of their own, the mutations were identical.

A single genetic mutation causes resistance to DDT and pyrethroids (an insecticide class used in mosquito nets), new research concludes. With the continuing rise of resistance, the research is key as scientists say that this knowledge could help improve malaria control strategies. The researchers used a wide range of methods to narrow down how the resistance works, finding a single mutation in the GSTe2 gene, which makes insects break down DDT so it's no longer toxic. They have also shown that this gene makes insects resistant to pyrethroids raising the concern that GSTe2 gene could protect mosquitoes against the major insecticides used in public health.

Gregory Lanzaro, medical entomologist and professor at University of California Davis (UC Davis) and leader of the research team behind the discovery, says they are calling the hybrid mosquito a "super" mosquito because it can survive exposure to the insecticides used to treat bed nets. He and his team report their findings in the Proceedings of the National Academy of Sciences.

The CDC released travel health notices Tuesday that named two more places in which the disease has spread via mosquito bites: The US Virgin Islands and the Dominican Republic.  The Zika virus is primarily transmitted by Aedes aegypti, the type of mosquito responsible for spreading dengue, yellow fever, and a whole host of other tropical infectious diseases. Originally identified in 1947 in Uganda, Zika was relatively unknown until 2007, when there was an outbreak of the virus in Micronesia. The mosquitoes pick up the virus from infected people, according to the CDC. 

This directed case study in PowerPoint format focusses on the London Underground Mosquito, Culex molestus, and its potential relationship to the common mosquito, Culex pipiens, in order to explore the topics of evolution, reproductive isolation, and speciation. As the story unfolds, the case mirrors the process of science. The students receive some initial data and observations collected by Byrne and Nichols in London. Based on these observations, the students then form a hypothesis and design an experiment. Finally, they receive more data collected by Becker et al. and draw conclusions.

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.

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.

Unprecedented multiple and extreme-level resistance is generated in mosquitoes found in the rice fields of Tiassalé in southern Côte d'Ivoire. A new study highlights the combination of stringently-replicated whole genome transcription profiling, in vivo transgenic gene expression and in vitro metabolism assays to identify and validate genes from the P450 detoxification enzyme superfamily which are highly expressed in the adult females from the area.

It may seem counter-intuitive at first but letting mosquitoes grow up and breed may be part of the solution to tackling the devastating impact of malaria. Researchers have used mathematical modeling to examine why conventional insecticides used against the insects that transmit the disease responsible for millions of deaths a year, can quickly become ineffective in areas of intensive use. Their answers may lead to unprecedented advances in malaria control.

The Aedes aegypti mosquito is the major vector for transmission of numerous viral diseases, including yellow fever, dengue, and now, Zika. Interestingly, different subspecies of A. aegypti are known to exist in close proximity but with considerable genetic divergence between them. One major difference between a "forest" form and a "domestic" form is a strong preference in the latter subspecies for human over non-human blood biting. This difference was explored with genetic and neurophysiological approaches by a research group at Rockefeller University and published in a 2014 paper in Nature. This flipped case study uses parts of the Nature paper to focus on elements of the scientific method as well as evolutionary questions raised by the difference in biting preference between the two subspecies. Students prepare for class by watching a video that provides background information about the published study that forms the basis for the case. In class students then work in groups to develop a hypothesis, predictions and proposed experiments to test the idea of different biting preferences.

Why they bite preferentially in 1 minute.

Why do we smell different when we're sick? Why does cheese smell like feet? Why don't vultures get sick from eating rotting meat? Science is filled with stories: some of them are beautiful and some of them are gross. Really gross. Gross Science, a YouTube series hosted by Anna Rothschild, tells bizarre stories from the slimy, smelly, creepy world of science. In this collection, you'll find original short-form videos and DIY experiments from Gross Science, which is produced by NOVA and PBS Digital Studios. Learn about amphibians that eat their mother's skin, strange uses for bacon, how poop can be used to cure an infection, and more gross science topics.

4:17 video malaria life cycle

Scientists and healthcare professionals initially exhibited little concern over the Zika virus even after evidence of human infection was first identified in 1952; Zika appeared to be both rare and unassociated with morbidity or mortality. Around 2015 all of this changed as journalists, scientists, public health officials, and laypeople scrambled to learn about its varied modes of transmission and devastating consequences (e.g., birth defects and autoimmune disorders). Although research continues to rapidly evolve, this case study directs students to reliable scientific sources (e.g., Centers for Disease Control and World Health Organization) that will likely continue to provide the most current information in order to explore questions such as: Where did the virus come from? How does it spread? What can we do to prevent it? Students will also consider the public health challenges and possible solutions associated with emerging infectious diseases. The case was originally written for an upper-level biology or public health course in which students already have some basic background knowledge regarding viruses, vaccines, and infectious disease.