Oropouche Virus in the U.S: 3 Points to Know

 

Oropouche Virus in the U.S: 3 Points to Know

Introduction

Oropouche virus disease, also known as Oropouche fever, is a viral infection transmitted through the bites of infected biting midges and some mosquitoes.

It is most prevalent in Central and South America, and the Caribbean, with recent outbreaks in Cuba.

The disease typically presents with flu-like symptoms such as sudden onset of fever, severe headache, chills, muscle aches, and joint pain.

Other symptoms may include sensitivity to light, dizziness, pain behind the eyes, nausea, vomiting, and rash. Although the virus is not currently a major public health threat in the United States, it is being closely monitored due to its recent spread in the Americas and cases identified among U.S. travelers returning from Cuba.

The CDC is actively working on rapid detection, surveillance, and response plans for potential cases in the U.S. U.S. residents, especially travelers to affected regions, should stay informed through the CDC’s Travelers’ Health notices and take preventive measures

What is Oropouche Virus?

Origin and Transmission :

The Oropouche virus originates from parts of South America, Central America, and the Caribbean.

It is an RNA virus belonging to the Simbu serogroup of the genus Orthobunyavirus in the family Peribunyaviridae.

The primary transmission method of Oropouche virus to humans is through the bite of infected biting midges (Culicoides paraensis). Some mosquitoes, including Culex quinquefasciatus, Coquillettidia venezuelensis, and Aedes serratus, can also spread the virus.

The virus is maintained in a sylvatic cycle in forested areas between mosquitoes and non-human vertebrate hosts, such as three-toed sloths, certain non-human primates, and birds.

In urban areas, the virus is primarily transmitted by biting midges from an infected person to an uninfected person. There is no evidence of direct human-to-human transmission through coughing, sneezing, or touching.

1. Symptoms

The symptoms of Oropouche Virus include sudden onset of fever, severe headache, chills, muscle aches, joint pain, sensitivity to light, dizziness, pain behind the eyes, nausea, vomiting, and rash.

Symptoms typically last less than a week (2–7 days) and can often reoccur a few days or even weeks later. Most people recover within several days to one month.

In rare cases, it can cause more serious conditions such as meningitis, encephalitis, or bleeding. Death from Oropouche is rare.

Current Status of Oropouche Virus in the U.S.

CDC Monitoring and Preparation

 The CDC is actively working on several fronts to monitor and prepare for Oropouche virus in the U.S. They are collaborating with state public health jurisdictions and international partners to enable rapid detection and surveillance of the virus.

The CDC is developing a plan for rapid detection and response to Oropouche virus cases, assisting health departments with clinical diagnostic and surveillance testing, and working to validate a molecular assay to detect acute infections.

They are also updating the Travelers’ Health notices and website with new information, providing clinical consultation and guidance to pregnant persons and their care providers, and tracking the impact of the virus on pregnant persons and their infants.

Although Oropouche virus disease is not nationally notifiable, the CDC encourages jurisdictions to report cases voluntarily to ArboNET using interim case definitions.

2. Travel-Associated Cases

As of August 16, 2024, there have been 21 travel-associated cases of Oropouche virus in the U.S. among travelers returning from Cuba. The emergence and spread of the virus in the Americas, including these cases, highlight the importance of rapid detection and response plans.

These plans are crucial for guiding public health prevention measures, enabling timely clinical diagnostic and surveillance testing, and providing necessary clinical consultation and guidance, especially for pregnant persons who are at risk of adverse pregnancy outcomes.

Rapid detection can help manage and mitigate the risk of local transmission and potential importation into unaffected areas in the United States.

3. Preventive Measures for Oropouche Virus

Personal Protection

To protect yourself against Oropouche virus, it is essential to prevent bug bites. Use EPA-registered insect repellents labeled for flies, biting flies, or Culicoides.

Wear long-sleeve clothing, use window and door screens with mesh measuring 20x20, and use fans when outdoors to blow away biting midges.

Avoid areas where mosquitoes and midges are most active, particularly at night and dawn. If traveling to areas with Oropouche virus, continue to prevent bites for 3 weeks after your trip to avoid spreading the virus.

Travel Precautions

Travelers should take several precautions to prevent insect bites and avoid Oropouche virus.

These include using an EPA-registered insect repellent, wearing long-sleeved shirts and pants, and staying in places with air conditioning or that use window and door screens.

It is also important to avoid areas where biting midges and mosquitoes are most active, typically at night and dawn, and to avoid forested areas where these insects are endemic.

Pregnant travelers should reconsider non-essential travel to areas with Oropouche virus and, if travel is necessary, strictly follow steps to prevent insect bites.

Treatment Options for Oropouche Virus

Symptom Management

Current treatment options for Oropouche virus focus on supportive care to manage symptoms, as there is no specific antiviral treatment available.

Recommended measures include rest, staying hydrated, and using over-the-counter pain relievers like acetaminophen to reduce fever and manage muscle and joint pain.

Nonsteroidal anti-inflammatory drugs (NSAIDs) should be avoided due to the risk of bleeding, especially if dengue fever is a possibility. Patients with worsening symptoms or those experiencing complications such as meningitis or encephalitis should seek medical attention promptly.

When to Seek Medical Attention

Seek medical attention for Oropouche virus symptoms if you experience an abrupt onset of fever, headache, and one or more of the following: myalgia, arthralgia, photophobia, retroorbital or eye pain, or signs and symptoms of neuroinvasive disease such as stiff neck, altered mental status, seizures, limb weakness, or cerebrospinal fluid pleocytosis.

Additionally, if symptoms reoccur after initial resolution, medical attention should be sought.

Pregnant persons should seek medical attention due to the risk of vertical transmission and potential adverse pregnancy outcomes.

Conclusion

In summary, the Oropouche virus is an emerging health concern in the Americas, including among U.S. travelers.

 Awareness and preventive measures, such as avoiding insect bites and staying informed through CDC updates, are crucial for protection.

Rapid detection and response plans are essential to manage and mitigate the virus's impact.

Sources:

1.  Oropouche Virus Disease.” Cleveland Clinic, 22 August 2024, https://my.clevelandclinic.org/health/diseases/oropouche-virus-disease.

2. “What Is the Oropouche Virus (Sloth Fever)?.” WebMD, 20 August 2024, https://www.webmd.com/a-to-z-guides/oropouche-virus-disease.

3. “Mysterious Oropouche virus is spreading: what you should know.” Nature, 26 August 2024, https://www.nature.com/articles/d41586-024-02746-2.

4. “Oropouche Virus Disease Among U.S. Travelers — United States, 2024.” Centers for Disease Control and Prevention (.gov), 27 August 2024, https://www.cdc.gov/mmwr/volumes/73/wr/mm7335e1.htm.

5. “About Oropouche.” Centers for Disease Control and Prevention (.gov), 29 August 2024, https://www.cdc.gov/oropouche/about/index.html.