"The groundwork of all happiness is health." - Leigh Hunt

What is Eastern Equine Encephalitis? Two mosquito researchers explain what's behind the most recent outbreak.

Health officials within the United States are issuing warnings. Closing public parks Caused by a rare but potentially fatal mosquito-borne disease.

This week, residents of the US state of New Hampshire… died After being hospitalized with eastern equine encephalitis. Cases have also been detected in other states.

But what's eastern equine encephalitis? How does it spread? What, because the name suggests, do horses should do with it? And is that this an issue for Australia?

What is Eastern Equine Encephalitis?

Eastern equine encephalitis Caused by a virus that is frequently found only in parts of the eastern United States. Central America To Canada.

Eastern equine encephalitis virus causes neurological disease, particularly encephalitis (inflammation and swelling of the brain), and is transmitted to humans by mosquito bites. Symptoms can be severe. And potentially fatal.

But most individuals bitten by a mosquito carrying the virus is not going to have symptoms. For those that develop the disease, symptoms include headache, neck stiffness, confusion, seizures and coma.

About a third Patients with severe symptoms will die, and plenty of who survive have neurological problems.

It's not only people who find themselves in danger from the virus. There are horses. Sensitive too And, as in humans, fatal encephalitis can develop after being bitten by an infected mosquito.

This virus was discovered after the outbreak of Malignant disease in horses within the New England region of the United States in 1831, hence the reference to the horse disease named after him.

Wild, farmed and captive birds can. Also affected Disease occurs with viruses and in some species. In fact, birds are key to how the virus spreads.

How is Eastern Equine Encephalitis Virus Spread?

Birds – especially The passer-bya bunch that features robins, starlings, thrushes and blue jays – are the principal hosts of the virus.

These birds produce. Quite a lot The level of virus that infects and sustains biting mosquitoes is named the “transmission cycle.”

Mosquitoes feeding on birds in forested wetlands, particularly, allow the virus to flow into amongst birds. But this mosquito rarely bites people, so it will not be that essential for spreading human disease.

It is mosquitoes that feed on each. Birds and mammals which transmits the virus to humans and horses. These include, and mosquitoes. But once infected, humans and horses don't spread the virus. This is because they don't produce high enough levels of virus to contaminate mosquitoes.

Screens are one solution to limit contact with mosquitoes.
A/Professor Cameron Webb (NSW Health Pathology)

How can we limit the spread?

There isn't any specific treatment for eastern equine encephalitis virus infection. or any licensed vaccine For use in humans. There is a vaccine. Registered for veterinary use To prevent virus infection in horses.

Personal protective measures and mosquito control are essential strategies for limiting people's exposure to the virus.

Outbreaks can have a big impact on communities, not only from the disease itself, but from measures implemented to limit transmission.

Outdoor events have been canceled on account of recent outbreaks. There have also been concerns in regards to the widespread use of aerial “fogging” to kill mosquitoes since the chemicals commonly used will not be mosquito-specific and should pose a threat to other pests.

Some towns have Closed Parklands within the evening and told residents to not enterprise out at night.

Why is the epidemic spreading now?

This virus circulates all year long in tropical regions. Like Florida. This is the virus within the northeastern United States. More sporadic activity. Here, it is frequently introduced by migrating birds and is lively throughout the warmer months when mosquito populations thrive.

The virus has been known for a long time and a number of other outbreaks have been reported in North America. One of the last coffee spills It was in 2019. In several northeastern US states, when there have been 38 human cases (including 12 deaths).

The evidence is there. The virus is spreading In the New Territories of North America. But, given the sporadic nature of outbreaks, it's difficult to predict when they'll occur.

A number of factors Factors more likely to play a task in determining future outbreaks and the spread of the virus to recent regions, including climate, environmental aspects, mosquito and wildlife activity, and, importantly, people.

With increased contact between people and mosquitoes that may transmit the virus from infected birds, public health risks increase.

Perhaps human activities around mosquito and bird habitats, including urban development encroaching on forested wetlands, increase the chance.

It is subsequently essential for health authorities to watch mosquito and virus activity. To provide early warning from the chance of human disease.

New Hampshire Pond and Wetland Systems
Mosquitoes present in forested wetlands allow the virus to spread to birds.
Jeff Holcomb/Shutterstock

Is Australia in danger?

There isn't any evidence that eastern equine encephalitis virus is present in Australia and there is no such thing as a immediate risk of its introduction here.

While the mosquito Found in Australia.their role in local virus outbreaks in humans or animals will not be well understood.

But it includes dozens of various mosquitoes. Spread of alpha virus In Australia it's the group that features Eastern equine encephalitis viruses, in addition to those endemic to Australia, viz. Ross River And Burma Forest The virus

It is affordable to assume that a few of these mosquitoes may have the opportunity to transmit the virus, but this has not been tested in laboratory experiments.

Little is understood about how native passerine birds may play a task in establishing viral transmission cycles in Australia. There can also be no information on whether native Australian vertebrates, akin to marsupials, will reply to infection.

When we consider all of the available evidence, the chance of the virus spreading and spreading in Australia is, probably, very low.

Are travelers in danger?

The risk of being bitten by a mosquito carrying the Eastern Equine Encephalitis virus may be very low. But anyone traveling to eastern North America, including the United States and Canada, where the virus could also be present should take precautions to avoid mosquito bites.

Follow up. Instructions from local health authorities. And take steps to avoid places (especially forested wetlands) and times when mosquitoes are lively (normally morning and evening). Wear loose-fitting clothing with long sleeves and apply a repellent containing diethyltoluene (commonly referred to as DEET), picardin, or oil of lemon eucalyptus.

These precautions may also protect against other mosquito-borne virus infections you might encounter there, akin to West Nile virus.