Over 4,000 cases of Oropouche virus were reported in Cuba in 2025. Particular concern is the possible mother-to-child transmission, which can result in stillbirths and malformations. Sexual transmission is also discussed.
So far in 2025, 4,119 cases of the Oropouche virus (OROV) have been reported in Cuba, of which 36 were laboratory-confirmed infections. The virus, which is mainly caused by mosquitoes of the species Culicoides paraensis can cause flu-like symptoms, including sudden fever, severe headache, muscle aches, chills, nausea and sensitivity to light. The illness typically lasts three to six days, but in individual cases it can last for weeks or be severe – for example in the form of aseptic meningitis. The incubation period is usually four to eight days.
The potential vertical transmission of OROV requires particular attention. Studies from Brazil report stillbirths, miscarriages and newborns with microcephaly, possibly due to infection. Although a direct causal connection cannot currently be established, the evidence of mother-to-child transmission is clear enough that the US CDC is warning pregnant women and calling on doctors to closely monitor infections during pregnancy.
In addition, the virus, which can multiply in the body, was detected in the semen of infected people. There is therefore evidence of sexual transmission, even if no confirmed cases have been reported to date. The CDC therefore recommends taking extra caution when traveling to affected areas. This includes the consistent use of insect repellent, sleeping under impregnated mosquito nets and wearing puncture-proof clothing. For travelers who are sexually active, using condoms or abstaining from sexual contact during the trip and for six weeks after return may also be considered as a precautionary measure.
The virus is currently occurring in Cuba and several countries in South and Central America, including Brazil, Panama and Peru. Illnesses can affect people of all ages and are often confused with dengue fever. For travelers who develop symptoms such as high fever, headache, muscle pain, joint stiffness, nausea or sensitivity to light during or up to two weeks after their return, immediate medical evaluation is crucial. Aspirin or other anti-inflammatory medications such as ibuprofen should be avoided as they increase the risk of bleeding; Paracetamol is considered a safer alternative.
Recent reports highlight the need for preventive measures for travelers as well as raising awareness among healthcare workers about the risks of OROV, especially in pregnant women. Despite the low number of cases in Cuba so far, the virus circulation must be taken seriously, not least because of possible serious consequences for unborn children.
