Health authorities have issued a travel warning after 19 cases of the vector-borne disease Oropouche virus were confirmed in Europe for the first time. Those who tested positive for the virus had recently returned from holidays in Cuba and Brazil.
Parts of South America and Cuba are currently experiencing Oropouche virus outbreaks, with many times more cases than usual, and Brazil recently reported its first death from the virus, raising concerns about the current outbreak.
Oropouche virus is an arthropod-borne virus that is transmitted to humans through the bite of infected midges or mosquitoes and is the second most prevalent arthropod-borne viral disease in South America after dengue virus.
The virus was first identified in forest workers working near the Oropouche River in Trinidad and Tobago in 1955. The first major outbreak was reported in Belém, Brazil, in the 1960s, when 11,000 cases were recorded.
Since then, there have been repeated outbreaks of the Oropouche virus, and it is estimated that more than 500,000 people have been infected with the Oropouche virus since it was first detected.
Outbreaks occur mainly in tropical areas of South America, Central America, and the Caribbean (mainly the Amazon region of Brazil and Peru).
Oropouche virus is transmitted to humans through the bite of infected midges or mosquitoes that live mainly in forested areas and around bodies of water. Transmission usually occurs during the day, especially at sunrise and sunset.
Symptoms of Oropouche virus disease are very similar to influenza, causing sudden fever, headache, dizziness, chills, muscle aches, pain, and sensitivity to light. These symptoms usually last for 2-5 days after being bitten by an infected insect.
Most people recover with no long-term effects, but symptoms may return if they return to strenuous activity too soon after becoming ill.
Unfortunately, there is no specific antiviral treatment for Oropauche virus disease, but patients can be treated with painkillers and hydration to manage symptoms.
Although the Oropouche virus is not generally fatal, it can cause severe complications, such as encephalitis and meningitis. Recently, two young Brazilian women died after contracting the Oropouche virus and experiencing a sudden onset of symptoms that led to bleeding.
The virus may also be linked to a spate of miscarriages, stillbirths and birth defects in Brazil.
Increasing number of infected people
Between January and mid-July of this year, Oropouche virus infections surged in the Americas, with more than 8,000 confirmed cases.
More than 7,000 of these cases are in Brazil, a significant increase from the 832 cases reported in the country last year. Not only is the sudden increase in cases worrying, but it is also worrying that for the first time the virus has directly caused two deaths, and that infections are now being reported in areas where the Oropouche virus has not previously been detected.
It’s not yet fully clear why there are so many Oropouche virus cases this year, but climate change may be a factor: warmer temperatures in the region are causing insects to mature earlier, and flooding can also increase standing water, creating ideal conditions for insects to breed.
Other factors that may be contributing to the increase in Oropouche virus include deforestation (which causes mosquitoes to move and feed on humans instead of animals) and increased movement of people between forested and urban areas across the continent.
Mutations may also affect the virus’s infectivity, disease-causing ability, ability to spread and ability to evade the immune system. Preliminary evidence indicates that mutations and genetic changes in the virus’ genome may underlie the current outbreak.
Despite the significant threat that Oropauche virus poses to public health, there is currently no licensed vaccine to prevent the disease.
Therefore, the best way to protect yourself from Oropauche virus disease is to avoid insect bites in areas where the virus is present, especially in South America, Central America, and the Caribbean.
The best way to prevent insect bites is to use insect repellent. Look for products that contain picaridin and diethyltoluamide (DEET).
Aim to apply a thin, even layer of repellent to exposed skin. Reapply periodically as needed, especially after swimming or if you sweat. Apply repellent over your sunscreen.
In addition to using insect repellent, you can also wear long clothing that covers your arms and legs, and if indoors, cover doors and screens to keep mosquitoes from getting in. Electric fans can also help keep bugs away.
You should also be sure to remove any food remains, dead leaves, and pools of water around your home to reduce places for female insects to lay their eggs.
Despite the confirmed imported cases, it is thought that the likelihood of Oropouche virus spreading in the UK or Europe is very low as the virus spreads from insects to humans and no cases of human-to-human transmission have been reported to date.
People traveling to areas where infections are common (such as Brazil) should be especially careful and take precautions to avoid contracting the virus.
Manal Mohammed, Senior Lecturer in Medical Microbiology, University of Westminster
This article is republished from The Conversation under a Creative Commons license. Read the original article.
