Bolivian hemorrhagic fever

Bolivian Hemorrhagic Fever (BHF), also known as Black Typhus or Ordog Fever, is a zoonotic disease caused by the Machupo virus, a member of the Arenaviridae family. The disease was first identified in 1963 in Bolivia after an outbreak in the small village of San Joaquín in the Beni Department. BHF is characterized by fever, malaise, headache, joint and muscle pain, followed by hemorrhagic manifestations and, in severe cases, can lead to death.

Etiology

BHF is caused by the Machupo virus, which is transmitted to humans through aerosolized or direct contact with the excreta of infected Calomys callosus rodents, which are the natural reservoirs of the virus. Human-to-human transmission can occur through direct contact with bodily fluids of infected individuals.

Epidemiology

The disease is endemic to specific regions of Bolivia, primarily in the tropical areas of the Beni Department. Outbreaks are sporadic and are often associated with agricultural activities that increase human contact with the rodent reservoir.

Clinical Manifestations

The incubation period of BHF ranges from 7 to 14 days, after which the initial symptoms, including fever, fatigue, headache, and muscle pains, appear. As the disease progresses, more severe symptoms such as hemorrhagic signs (e.g., bleeding gums, nosebleeds), neurological manifestations (e.g., tremors, confusion), and shock may develop. Without treatment, BHF has a high mortality rate.

Diagnosis

Diagnosis of BHF is primarily based on clinical symptoms and epidemiological factors, such as exposure history. Laboratory confirmation can be achieved through various methods, including virus isolation, RT-PCR, and serological tests to detect specific antibodies against the Machupo virus.

Treatment

There is no specific antiviral treatment for BHF. Management of the disease is supportive and includes maintenance of hydration, management of shock, and administration of antipyretics for fever. Ribavirin, an antiviral drug, has shown some efficacy in treating BHF when administered early in the course of the disease.

Prevention

Preventive measures focus on controlling the rodent population to reduce human exposure to the virus. Public health education on avoiding contact with the rodents and their excreta is crucial. Personal protective measures, such as the use of gloves and masks when handling potentially infected materials, are also recommended. There is currently no vaccine available for BHF.

See Also

• Viral hemorrhagic fever
• Arenaviridae
• Zoonosis