West Nile virus is the most common mosquito-borne illness in the continental U.S., with an average of 2,464 reported cases per year.

Every August, West Nile season ramps up, primarily in parts of the Southern and Western United States.

The Conversation U.S. asked neurologist and medical epidemiologist Daniel Pastula to explain what researchers know about West Nile and how to protect yourself from contracting the disease.

What is West Nile virus?

West Nile is a virus that was first identified in the West Nile region of Uganda in 1937 and subsequently caused outbreaks throughout Africa, the Mediterranean region and parts of Europe.

It arrived in the New York City area in late 1999, probably from an infected bird or mosquito. The virus has since spread and become endemic throughout the continental United States and other parts of North America.

How is West Nile virus transmitted?

West Nile virus is primarily transmitted to humans by mosquito bites. West Nile virus exists in a transmission cycle between various birds such as crows, robins and blue jays and primarily several Culex species of mosquitoes, which are very common across the U.S.

The mosquitoes become infected by feeding on infected birds with high levels of virus. Then the infected mosquitoes pass the virus to other birds by feeding on them.

Sometimes, an infected mosquito will bite a human, horse or other mammal, transmitting the virus to them. However, these animals do not develop a high enough viral level in their blood to keep the cycle going. In other words, they are “dead-end” hosts.

Rarely, West Nile virus is transmitted in other ways, including through accidental laboratory exposures, blood transfusion or organ transplantation. Very rarely, it may be transmitted during pregnancy, delivery or through breastfeeding.

When and where does it show up, and is it seasonal?

In the continental U.S., most human cases of West Nile virus disease occur from July through September, or until the first hard freeze or snowfall. This is commonly called “West Nile season.” By this time of year, mosquitoes have had enough time to emerge, feed on infected birds and become infected themselves.

In more southern areas such as Arizona, Florida and Texas, mosquito transmission may occur earlier than July and later than September. For example, mosquitoes infected with West Nile virus were reported in Texas as early as May 2024.

While human cases of West Nile virus disease have occurred in the 48 continental states, the District of Columbia and Puerto Rico, the majority of cases over the past two decades have been in the Great Plains, Southern and Southwestern United States. This likely has to do with the types of mosquitoes, birds, bird migration patterns, temperature, rainfall and irrigation practices in these areas.

How dangerous is West Nile?

Approximately 80% of people infected with West Nile virus have no symptoms or very mild ones.

But about 20% of the time, people infected with West Nile virus can develop a sudden flu-like illness with symptoms such as high fever, headache, muscle and joint aches, stomach problems such as nausea, vomiting and diarrhea, rash and fatigue within two to 14 days after being bitten by a West Nile-carrying mosquito.

Most people recover from this “West Nile fever,” but the fatigue may last weeks to months.

In about 1% of cases, however, the virus can invade the covering of the brain, causing what is called meningitis; the brain itself, resulting in encephalitis; or the spinal cord, causing a polio-like syndrome. When the virus invades the nervous system like this, it is called “West Nile neuroinvasive disease.”

Approximately 10% of West Nile neuroinvasive disease cases are fatal, particularly in cases where the brain and spinal cord are directly infected. Many survivors are left with permanent neurological disability such as weakness, movement disorders or cognitive issues to varying degrees.

The risk of West Nile neuroinvasive disease is higher in people who are 60 or older, those who are immunocompromised and those with conditions such as cancer, diabetes or kidney failure.

Are there any treatments or vaccines?

While a variety of treatments have been investigated, there are currently no proven antiviral treatments for West Nile virus disease. Treatment remains largely focused on addressing symptoms.

Some patients may require over-the-counter medications for fever and headaches, fluids for dehydration, anti-nausea medications for nausea or vomiting, and rest. Some may require hospitalization and treatment for severe dehydration, organ dysfunction, seizures or brain swelling.

There are currently no West Nile vaccines licensed for use in humans, though some vaccine candidates and ideas are being studied.

How can you help prevent it?

Generally speaking, if you prevent mosquito bites, you prevent West Nile virus infection. There are several things you can do to prevent mosquito bites:

First of all, use an Environmental Protection Agency-registered insect repellent on exposed skin when you are outside in an area with mosquitoes. These are safe and effective when used as directed.

You can also wear long-sleeved shirts and pants when feasible. It is much harder – or even impossible, depending on the fabric – for mosquitoes to bite through clothing. You can also treat your clothing with permethrin, an insecticide, which further repels mosquitoes.

When possible, avoid being outside between dusk and dawn. This is when the West Nile-carrying mosquitoes are most active.

It’s also a good idea to get rid of any unneeded standing water in places such as birdbaths or kiddie pools around your property, as mosquitoes like to breed in standing water. When indoors, be sure that any unscreened windows are closed to keep mosquitoes outside. These simple precautions can greatly reduce the risk of getting severely ill.

In addition to these precautions for individuals, robust public health and vector control programs help to monitor and control the spread of West Nile virus by warning area residents of the presence of the virus and reducing infected mosquito populations when necessary.

Daniel Pastula, Professor of Neurology, Medicine (Infectious Diseases), and Epidemiology, University of Colorado Anschutz Medical Campus

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The racially motivated tragedy in Charleston, South Carolina, in 2015, when a white supremacist murdered nine Black worshippers, and the deadly white nationalist rally in Charlottesville, Virginia, two years later compelled Americans to confront the role played by memorials, monuments and other symbols in glorifying racist ideologies.

George Floyd’s murder at the hands of a white Minneapolis police officer in 2020 only lent urgency to that challenge.

Part of the racial reckoning in the wake of Floyd’s death is a movement to remove offensive names from public places. Some names perpetuate demeaning slurs and stereotypes against people of color. Others honor historical figures linked to racism and colonization. This movement is what we geographers call America’s “renaming moment.”

Government officials, activists and other people have called for a renaming of certain places and institutions. Examples include removing Christopher Columbus’ name from a Chicago public school and erasing the name of former KKK leader and governor Bibb Graves from a University of Alabama building. The elimination of names of Confederate generals from several U.S. military bases provides another example.

These changes have become flash points of community activism and debate, both in support of and in resistance to name revisions.

A widespread element in this renaming moment are offensive street names. We believe discussions and decisions about removing these names may benefit from comprehensive sources of information that allow the public to know how pervasive a problem the country might be confronting.

The recent release of an app developed by STNAMES LAB, an international team of scholars of place names, allows users to conduct nationwide inventories of discriminatory roadway names, revealing how often and where they are found.

We believe the app is an important educational tool. It will help communities understand how discriminatory beliefs are woven into everyday spaces and the harm caused by offensive names.

After tracking a few of America’s most contested place and institution names, we believe the app will help people see the changes necessary to recognize and repair past wrongs in street naming.

Recognizing that names can harm and heal

There is growing public recognition that place names are not neutral identifiers of locations. Rather, place names can transmit harmful messages that misrepresent the history and identity of minority communities. As a result, they work against the possibility of a more equal society.

One highly publicized effort at identifying and replacing offensive place names happened in November 2021.

U.S. Interior Secretary Deb Haaland, the first Native American to hold that post, ordered the removal of the word “squaw,” hereafter called “sq—,” from the names of 650 mountains, rivers and other sites on federal lands. Haaland’s order capped many years of demands from Native American groups to eradicate the racist and sexist label.

Then, in 2022, Haaland established the Advisory Committee on Reconciliation in Place Names, comprising members from tribal nations, Native Hawaiian organizations and scholars. Its guiding principles call on the U.S. to recognize the historical role of racism and sexism in naming places. They also highlight how those in power have used names to disrespect, misrepresent and control certain groups that have been historically discriminated against.

Drawing from public comments over two years, the committee found that derogatory place names are a source of recurring trauma for groups that have been historically discriminated against. As one Native American community leader told the committee, “Names matter, as they can build or break a relationship with the land and have the power to uplift or marginalize communities.”

Similarly, a 2022 report by the National Association of Tribal Historic Preservation Officers and the Wilderness Society found derogatory place names can create an unwelcoming environment that some people avoid. Additionally, a 2022 study by Emory University found that homes on streets named for pro-slavery Confederate figures sell for less and take longer to sell than comparable houses on nearby roads.

Renaming roads serves as an important moment of community reconciliation. That’s because the frequent use of offensive street names exacts a hefty social and psychological toll on marginalized communities, according to the cultural historian Deirdre Mask.

When hurtful names are removed from roads, some members of oppressed communities describe how the spirit or feeling of places can change and allow healing to begin.

The difference an audit makes

The Interior Department committee suggests that efforts to change offensive names should be driven by research. It encourages local residents to identify where derogatory place names exist, when and how they were named, and how those names can harm the well-being of community members.

Data scientist Catherine D’Ignazio and her team at the Data + Feminism Lab agree. They call for conducting audits that collect and visualize data on unjust names, to challenge the damaging effects and abuses of power behind these symbols.

The newly released street names app from STNAMES LAB allows people to do that. Fed with Open Street Map data, it lets users carry out queries, as well as map and download streets containing certain terms.

Once users enter a name, they can check the specific location of named roads on a map. They can also download query results as a spreadsheet to get the full list of streets.

The app offers an easy visualization of the frequency and geographic distribution of names. You can see whether the name is found across the nation or concentrated in a specific region.

Demonstrating the app

To illustrate the app’s capabilities, we searched for names that have sparked public controversy.

Federal condemnation of “sq—” as a place name does not mean that local authorities will follow suit, even if some cities and states are already doing so. We found 429 streets scattered across 47 states with a name containing the word “sq—.”

Although “sq—” originated in the Algonquian language, European settlers corrupted and misused the word in reducing Native American women to a simplistic and sexualized image. Being called “sq—” is still a painful daily reality for Indigenous women. Many of them say the term injures their self-image and sense of belonging.

The street name app exposes other racist Native American stereotypes. Variations of “redman/men” and “redskin” appear on 211 roads.

“Redskin” is a portrayal of Native Americans as warlike and dangerous. According to Native writer Angelina Newsome, colonialists often used it interchangeably with “savage.”

We found 415 roads in 46 states using the word “savage” in their name.

Though references to “redman” and “redskin” have long shown up in consumer products and sports team mascots, many Native groups challenge these stereotypes as demeaning.

Searching for offensive street names across the country is about more than simply collecting information. Data and maps can be part of the process of expanding one’s sphere of awareness and caring for people living with unjust naming practices.

Tracking and visualizing these inequalities is key to developing the “civic imagination” that scholar Catherine D'Ignazio believes is necessary to imagine and call for more inclusive alternatives to the current American landscape of names.

What is at stake is not just removing insulting names in and of themselves, but ensuring that the places marked by these names feel more welcoming and respectful of all Americans.

Derek H. Alderman, Professor of Geography, University of Tennessee; Daniel Oto-Peralías, Associate Professor of Economics, Profesor Titular de Economía, Universidad Pablo de Olavide, and Joshua F.J. Inwood, Professor of Geography and Senior Research Associate in the Rock Ethics Institute, Penn State

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Did you know that the bananas you eat today are not the same type as the ones people were eating a few generations ago? The banana you might have had with your breakfast today is a variety called the Cavendish banana, while the one that was in grocery stores up to the 1950s was a variety called Gros Michel, which was wiped out by a disease called Fusarium wilt of banana, or FWB.

FWB of Gros Michel was caused by Fusarium oxysporum race 1, a fungal pathogen that affects bananas. This fungal infection kills a plant by occupying its vascular system, blocking water and mineral transportation.

Plant biologists developed the Fusarium-resistant Cavendish variety to replace the Gros Michel. Yet, over the past few decades, a resurgence of FWB caused by a different strain of the same fungus called tropical race 4, or TR4, is once again threatening global banana production.

How did Fusarium oxysporum gain the ability to overcome resistance and infect so many different plants?

The two-part genome of F. oxysporum

I am a genomicist who has spent the past decade studying the genetic evolution of Fusarium oxysporum. As a species complex, F. oxysporum can cause wilt and root rot diseases in over 120 plant species. Certain strains can also infect people.

In 2010, my lab discovered that each F. oxysporum genome can be divided into two parts: a core genome shared among all strains that codes for essential housekeeping functions, and an accessory genome varying from strain to strain that codes for specialized functions like the ability to infect a specific plant host.

Each species of plant has a sophisticated immune response to defend against microbial invasion. So to establish an infection, each F. oxysporum strain uses its accessory genome to suppress a plant’s unique defense system. This functional compartmentalization allows F. oxysporum to greatly increase its host range.

In our newly published research, my team and colleagues in China and South Africa found that the TR4 strain that kills Cavendish bananas has a different evolutionary origin and different sequences in its accessory genome compared with the strain that killed Gros Michel bananas.

Looking at the interface of where the TR4 strain is battling with its Cavendish banana host, we found that some of its activated accessory genes release nitric oxide, a gas harmful to the Cavendish banana. This sudden burst of toxic gases facilitates infection by disarming the plant’s defense system. At the same time, the fungus protects itself by increasing production of chemicals that detoxify nitric oxide.

Increasing banana diversity

In tracing the global spread of this new version of Fusarium oxysporum, we realized that a major cause for the recent resurgence of this fungal infection is the domination of the international banana industry by a single clone of banana.

Growing different varieties of bananas can make agriculture more sustainable and reduce disease pressure on a single crop. Farmers and researchers can control Fusarium wilt of banana by identifying or developing banana varieties that are tolerant or resistant to TR4. Our findings suggest that another way to protect Cavendish bananas would be to design effective nitric oxide scavengers to reduce the toxic pressure of the gas burst.

It can be hard to imagine how a consumer who simply enjoys eating bananas could participate in the battle against the disease devastating banana crops. However, consumers determine the market, and farmers are forced to grow what the market demands.

You can help increase banana diversity in your supermarket by intentionally trying one or more of the other hundreds of other existing banana varieties when they show up there. You can also buy local varieties of other fruits and agricultural products to help preserve plant diversity and support local growers.

Collaboration among scientists, farmers, industry and consumers around the world can help avoid future shortages of bananas and other crops.

Li-Jun Ma, Professor of Biochemistry and Molecular Biology, UMass Amherst

This article is republished from The Conversation under a Creative Commons license. Read the original article.