PAHO publishes update on Oropouche fever in the Americas

Maruim (Culicoides paraenses) y del mosquito Culex quinquefasciatus, vectores del virus Oroupuche
©Bruna Lais Sena do Nascimento - Laboratório de Entomologia Médica/SEARB/IEC
Credit

Washington, DC, September 10, 2024 (PAHO) – The Pan American Health Organization (PAHO) recently issued an update on Oropouche fever (OROV) in the Americas, urging countries to strengthen surveillance, report any unusual events, and reinforce vector prevention and control measures.

In 2024, the virus has been detected in areas where transmission had not been previously reported. Deaths associated with the infection were also reported, as were cases of vertical transmission. Since the last PAHO epidemiological alert, issued on August 1, 2024, and up to September 6, 1,774 additional cases of Oropouche have been reported in six countries, increasing the total to 9,852 confirmed cases. Brazil remains the most affected country with 7,931 cases and two deaths.

Other currently affected countries include Bolivia (356 cases), Colombia (74 cases), Cuba (506 cases), Peru (930 cases), and, more recently, the Dominican Republic (33 cases). Imported cases have also been recorded in the United States (21 cases) and Canada (1 case), following travel to endemic countries. Additionally, 30 imported cases have been documented in Europe.

Regarding mother-to-child transmission, a total of one fetal death and one case of congenital anomaly have been confirmed in Brazil. Currently, additional investigations are being conducted on other fetal deaths, miscarriages, and congenital anomalies.

Oropouche fever is a viral disease characterized by high fever, severe headache, and muscle and joint pain. In some cases, it can cause more severe complications such as meningitis or encephalitis. Although most people recover completely, there is no specific treatment, and prevention is essential.

The virus is primarily transmitted through the bite of infected midges, small insects that usually bite during the day and inhabit humid areas with organic matter and in forested areas.

Given the increase in cases in 2024, PAHO reiterates the importance of implementing preventive measures, especially for pregnant women. These measures include:

  • Using fine-mesh mosquito nets on doors and windows, with holes smaller than 1 millimeter, to prevent the entry of vectors.
  • Wearing long-sleeved clothing and long pants, especially in homes with a sick person.
  • Applying insect repellents containing DEET to exposed areas of skin.
  • In outbreak situations, outdoor activities should be avoided during dawn and dusk, when vector activity is highest.
  • Seek medical attention for any suspected symptoms.

PAHO continues to monitor the situation and work closely with member countries to control the spread of the virus and minimize its impact on public health.

On September 6, the Organization held a webinar focused on entomological surveillance and vector control of the Oropouche virus. Experts from PAHO, the Oswaldo Cruz Foundation (Fiocruz) in Brazil, and the United States Centers for Disease Control and Prevention (CDC) of the discussed key aspects of surveillance and control of the Culicoides paraensis midge and other potential vector species involved in the transmission of OROV.

During the event, PAHO presented Provisional Guidelines for entomological surveillance and prevention measures for vectors of the Oropouche virus, which address the life cycle of vectors, as well as methods for surveillance, capture, and processing of collected entomological material, among other aspects.

To view the webinar recording, click here.