Date: Wed 17 Jul 2019
Source: El Deber [in Spanish trans. ProMED Mod.TY, edited]
<https://www.eldeber.com.bo/extra/El-virus-Chapare-reaparece-despues-de-16-anos-y-no-se-sabe-que-roedor-lo-transmite-20190716-9370.html>

The 1st 3 cases of Chapare arenavirus haemorrhagic fever were detected between December 2003 and January 2004, but the vector [reservoir] was not identified. The affected individuals had febrile and cardiac symptoms.

The New World Chapare arenavirus haemorrhagic fever, which has recently affected 5 people in La Paz [department], 3 of whom died, had its 1st outbreak in 16 years in a rural locality in the Cochabamba tropics; however, since then, until now, the vector [reservoir] has not been identified.

It is known that arenaviruses are transmitted by rodents, and because of this the latest investigations in northern La Paz, where the 1st case was reported (that now is known as the Chapare genotype), was focused on searching for _Calomys callous_ [the large vesper mouse. - ProMED Mod.SH], which transmits Machupo virus, but it may also be transmitted by other rodent families, say knowledgeable people.

The chief of epidemiology of the Departmental Health Services (SEDES), Roberto Torrez, recalled that Chapare virus was identified more than a decade ago, after 3 people presented with haemorrhagic fever symptoms in the rural community of Samusaveti (Cochabamba tropics) between December 2002 and January 2004. The ill individuals presented with febrile and haemorrhagic symptoms and, mainly, cardiac problems. The investigation results indicated that they were dealing with a virus that was "very related" to Machupo, but was genetically distinct. In 2006, it was given the name Chapare, for the locality of its origin.

Torrez explained that the focus [of infection] was controlled, but the vector [reservoir] was not identified. Until now, it is still unknown how the virus has reappeared in northern La Paz, although the possibilities are that the vector [reservoir] has migrated from the Cochabamba tropics or has been inhabiting northern La Paz and that recently infected people have presented [with the disease]. "We know that it is transmitted by rodents, but we do not know the vector [reservoir] of the original Chapare virus, neither of the Cochabamba one, nor of the La Paz one," he said.

The chief of epidemiology discarded the idea that Santa Cruz department is at risk of an outbreak, since that "cases of the disease have never been registered nor have rodents of the _Calomys callous_ family [sic; genus and species] infected with Machupo virus been encountered." Torrez said that many years ago, in San Ignacio de Velasco, in the [municipal] limits of Piso Firme, _Calomys callous_ rodents were taken with Latino virus, which is not a human pathogen.

Technicians of the Ministry of Health have captured rodents in the areas of Caranavi and Guanay, where the 1st fatal case (a farmer) lived and worked. Since calomys rodents were not encountered, the investigation was expanded to other types of rodents.

[A hospitalized medical student who died 4 Jun 2019 was first diagnosed with dengue and later with a fatal arenavirus infection. The legal dispute between the patient's family and the hospital physicians is not translated here, since it adds nothing to the understanding of treatment or of epidemiology of the infection. - ProMED Mod.TY]  [byline: Deisy Ortiz, Miguel A Melendres]
====================
[New World arenavirus haemorrhagic fever virus Chapare, that has recently infected 5 patients in La Paz [department], 3 of whom died, brought to mind the 1st outbreak 16 years ago in a rural area of Cochabamba; however, since then it has not been possible to identify the animal reservoir. At that time, 3 people presented with symptoms of haemorrhagic fever in the rural community of Samusaveti (Cochabamba tropics) between December 2003 and January 2004. - ProMED Mod.JT]

This report definitely identifies the virus involved in these cases as Chapare arenavirus. Symptoms of Chapare and Machupo virus infections include: early clinical manifestations consist of nonspecific signs and symptoms, including fever, headache, fatigue, myalgia, and arthralgia. Within 7 days, patients may develop haemorrhagic signs, including bleeding from the oral and nasal mucosa and from the bronchopulmonary, gastrointestinal, and genitourinary tracts. Case fatality rates range from 5% to 30% (see ProMED-mail post Bolivian haemorrhagic fever - Bolivia: background http://promedmail.org/post/20190705.6553672).

The original cases were investigated by a team of Bolivian health authorities, US Navy health experts based in Lima, Peru, and the US Centers for Disease Control and Prevention. The virus was characterized as Chapare arenavirus, a previously unrecognized arenavirus, discovered in serum samples from a patient in rural Bolivia who eventually died of the infection. A full report of the study was published 18 Apr 2008 in the open-access journal PLoS Pathogens cited below.

Reference
---------
Delgado S, Erickson BR, Agudo R, et al. Chapare virus, a newly discovered arenavirus isolated from a fatal hemorrhagic fever case in Bolivia. PLoS Pathog. 2008; 4(4): e1000047; <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2277458/>

It is unfortunate that the rodent reservoir of Chapare virus is still unknown. - ProMED Mod.TY]

[HealthMap/ProMED-mail map of Bolivia:
<http://healthmap.org/promed/p/10123>]
Date: Thu 18 Jul 2019
Source: Centers for Disease Control and Prevention (CDC), Haemorrhagic Fever in Bolivia [edited]
<https://wwwnc.cdc.gov/travel/notices/watch/hemorrhagic-fever-bolivia>

Watch-level 1. Practice usual precautions
-----------------------------------------
Key Points:
- An outbreak of haemorrhagic fever was recently reported in Bolivia.
- The outbreak is caused by an arenavirus that appears similar to Chapare virus, which causes Chapare haemorrhagic fever.
- Travellers to Bolivia should avoid contact with rodents, with rodent urine or faeces (droppings), and with people who are sick.

What is the current situation?
Health officials in Bolivia have reported an outbreak of haemorrhagic fever associated with an arenavirus similar to Chapare arenavirus. The 1st case was in a man from Caranavi Province. A health care provider who treated him became ill and was transferred to La Paz. Currently, several additional cases have been reported; all have been in health care providers or family members of the 1st patient.

Testing suggests that the virus is genetically similar to Chapare virus, a New World arenavirus that was 1st documented in Bolivia in 2003. During that outbreak, a small number of people became ill, and one died. Since then, no additional cases have been reported. Additional testing is ongoing to determine the exact cause of this outbreak.

What can travelers do to protect themselves?
- Although the animal source for this virus has not been confirmed, travellers should avoid contact with rodents and rodent urine or faeces.
- Avoid contact with people who are sick.
- Travellers going to Bolivia to provide health care to local populations may be at risk and should wear full personal protective equipment when treating suspect hemorrhagic fever cases.
===========================
[The above CDC precaution is in response the recent occurrence of Chapare arenavirus hemorrhagic fever in the La Paz department of Bolivia (see Chapare virus - Bolivia: (LP) http://promedmail.org/post/20190719.6573996). The initial 3 cases of Chapare arenavirus hemorrhagic fever were detected between December 2003 and January 2004, but the vector [reservoir] was not identified. The virus recently affected 5 people in La Paz [department], 3 of whom died, had its 1st outbreak in 16 years in a rural locality in the Cochabamba tropics; however, since then, until now, the vector [reservoir] has not been identified.

As noted earlier, the original cases were investigated by a team of Bolivian health authorities, US Navy health experts based in Lima, Peru, and the US Centers for Disease Control and Prevention. The virus was characterized as Chapare arenavirus, a previously unrecognized arenavirus, discovered in serum samples from a patient in rural Bolivia who eventually died of the infection. A full report of the study was published 18 Apr 2008 in the open-access journal PLoS Pathogens cited below.

Citation
--------
Delgado S, Erickson BR, Agudo R, et al. Chapare virus, a newly discovered arenavirus isolated from a fatal hemorrhagic fever case in Bolivia. PLoS Pathog. 2008; 4(4): e1000047;
<https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2277458/>

The rodent reservoir of Chapare virus is still unknown. - ProMED Mod.TY]

[HealthMap/ProMED map available at:
Bolivia: <http://healthmap.org/promed/p/5>]
Date: Fri 5 Jul 2019
Source: GIDEON (Global Infectious Disease Epidemiology Network) [edited]
<http://www.gideononline.com>

Re: ProMED-mail Undiagnosed illness - Bolivia (02): (LP) Bolivian haemorrhagic fever conf. http://promedmail.org/post/20190704.6551379

In 2019, a small outbreak of Bolivian haemorrhagic fever was reported at a hospital in La Paz [department], Bolivia. The following background data on Bolivian haemorrhagic fever are abstracted from Gideon www.GideonOnline.com and the Gideon e-book series.[1,2] Primary references are available from the author.

Bolivian haemorrhagic fever (BHF) is caused by Machupo virus (Arenaviridae, Tacaribe complex, _Mammarenavirus_). The disease was initially described in 1959 as a sporadic hemorrhagic illness in rural areas of Beni department, eastern Bolivia, and the virus itself was 1st identified in 1963. BHF is most common during April to July in the upper savanna region of Beni. Principal exposure occurs through rodents ([the large vesper mouse] _Calomys callosus_), which enter homes in endemic areas.

BHF is one of several human _Arenavirus_ diseases reported in the Americas: Argentine haemorrhagic fever (Junin virus), Brazilian haemorrhagic fever (Sabia virus), lymphocytic choriomeningitis, Venezuelan haemorrhagic fever (Guanarito virus) and Whitewater Arroyo virus infection. (At least 2 related diseases are reported in Africa: Lassa fever and Lujo virus infection.)

Infection of _C. callosus_ results in asymptomatic viral shedding in saliva, urine, and feces; 50% of experimentally infected _C. callosus_ are chronically viremic and shed virus in their bodily excretions or secretions. _C. callosus_ acquires the virus after birth, and start shedding it through their urine and saliva while suckling. When mice acquire the virus as adults, they may develop immunity and no longer shed the virus.

Although the infectious dose of Machupo virus in humans is unknown, exposed persons may become infected by inhaling virus in aerosolized secretions or excretions of infected rodents, ingestion of food contaminated with rodent excreta, or by direct contact of excreta with abraded skin or oropharyngeal mucous membranes. Nosocomial and human-to-human spread have been documented. Hospital contact with a patient has resulted in person-to-person spread of Machupo virus to nursing and pathology laboratory staff.

In 1994, fatal secondary infection of 6 family members in Magdalena, Bolivia from a single naturally acquired infection further suggested the potential for person-to-person transmission.

During December 2003 to January 2004, a small focus of haemorrhagic fever was reported in the area of Cochabamba. A 2nd _Arenavirus_, Chapare virus, was recovered from one patient with fatal infection.

Early clinical manifestations consist of nonspecific signs and symptoms, including fever, headache, fatigue, myalgia, and arthralgia. Within 7 days, patients may develop hemorrhagic signs, including bleeding from the oral and nasal mucosa and from the bronchopulmonary, gastrointestinal, and genitourinary tracts. Case fatality rates range from 5% to 30%.

Ribavirin has been used successfully in several cases of BHF. The recommended adult regimen is 2.0 g intravenously (IV), followed by 1.0 g IV every 6 hours for 4 days, and then 0.5 g every 8 hours for 6 days.

Note that the etiologic agent and clinical features of BHF are similar to those of Argentine hemorrhagic fever (AHF). Neurological signs are more common in AHF, while hemorrhagic diatheses are more common in BHF. A vaccine available for AHF could theoretically be effective against BHF as well.

References
1. Berger S. American hemorrhagic fevers: global status, 2019. Gideon e-books.
<https://www.gideononline.com/ebooks/disease/american-hemorrhagic-fevers-global-status/>
2. Berger S. Infectious diseases of Bolivia, 2019. 342 pages, 87 graphs, 495 references.
<https://www.gideononline.com/ebooks/country/infectious-diseases-of-bolivia/>
-----------------------------------------
Communicated by:
Steve Berger
Geographic Medicine
Tel Aviv Medical Center, Israel
steve@gideononline.com
=======================
[ProMED-mail thanks Dr. Berger for the overview of Bolivian haemorrhagic fever presented above. As noted in the previous comment, and above, Bolivian haemorrhagic fever, caused by Machupo virus, occurs sporadically in lowland Bolivia, especially in Beni department. There was a case there in 2013, and in 2012 ProMED-mail reported that 13 people had been infected with Machupo virus and 7 had died as a consequence of the disease. In Beni department at that time, 5 municipalities, including Magdalena, were reported to have had large populations of _Calomys callosus_ mice, the reservoir host of Machupo virus, which can persistently infect the mice. It is not surprising to find cases in lowland areas of La Paz department again, where the current cases are occurring. The drylands vesper mouse, _C. musculinus_ mentioned in the previous post, although present in southern Bolivia, is unlikely to be the reservoir rodent involved in the current cases. _C. callosus_ mice are the recognized reservoir hosts of Machupo virus. Health officials can provide information about rodent control and assist in implementing it to reduce the risk of exposure to Machupo virus, but effective long-term implementation of rodent control ultimately rests with local residents.

An image of _C. callosus_, the large vesper mouse and reservoir host of Machupo virus, can be seen at
<http://www.faunaparaguay.com/calomyscallosus.html>. - ProMED Mod.TY]

[HealthMap/ProMED-mail map:
Bolivia: <http://healthmap.org/promed/p/5>]
Date: Wed 3 Jul 2019 11:53 BOT
Source: La Razon [in Spanish trans. ProMED Mod.TY, edited]
<http://www.la-razon.com/sociedad/Virus-salud-arenavirus-medicos-La_Paz-muerte-interna_0_3177282262.html>

[The Ministry of] Health confirmed that a virus that killed a hospitalized patient and 2 physicians from La Paz is an arenavirus transmitted by rodents. The disease, after 7 days, causes haemorrhagic fever, a symptom presented by the patients hospitalized in intensive care in 2 health centers in La Paz.

One of the viruses in this family is Machupo that causes Bolivian hemorrhagic fever, a disease that, according to hypotheses, is affecting the patients that are under observation, La Razon reported this [Wed 3 Jul 2019] in its printed edition.

"In laboratory terms, from national laboratories such as INLASA [Instituto Nacional de Laboratorios de Salud; National Institute of Health Laboratories] and CENTROP, [Centro de Enfermedades Tropicales; Tropical Diseases Center] they have identified an arenavirus," said Gabriela Montano in a press conference.

The report is also backed by a report from the [US] Centers for Disease Control and Prevention in Atlanta [CDC], Georgia, USA.

"We have a preliminary result from the CDC in Atlanta that also mentions an arenavirus. All of these elements together allow us to provide this information to the public today," the official added.

This virus is transmitted by rodents, specifically called the corn rat or _Calomys musculinus_, and it may also be transmitted person-to-person.  [Byline: Ruben Arinez]
=========================
[Bolivian haemorrhagic fever, caused by Machupo virus, an arenavirus, occurs sporadically in lowland Bolivia, especially in Beni department. There was a case there in 2013 and in 2012, ProMED-mail reported that 13 people had been infected with Machupo virus and 7 had died as a consequence of the disease. In Beni department at that time, 5 municipalities, including Magdalena, were reported to have had large populations of _Calomys callosus_ mice, the reservoir host of Machupo virus, which can cause persistent infections in the mice. It would not be surprising to find cases in lowland areas of La Paz department as well, where the current cases are occurring. The drylands vesper mouse, _C. musculinus_ mentioned above, although present in southern Bolivia, is unlikely to be the reservoir rodent involved in these cases. _C. callosus_ mice are the recognized reservoir hosts of Machupo virus. Health officials can provide information about rodent control and assist in implementing it, but effective long-term implementation ultimately rests with local residents.

An image of _C. callosus_, the large vesper mouse and reservoir host of Machupo virus can be seen at
<http://www.faunaparaguay.com/calomyscallosus.html>.

An image of _C. musculinus_, the drylands vesper mouse, can be seen at
<http://www.faunaparaguay.com/calomysmusculinus.html>. - ProMED Mod.TY]

[HealthMap/ProMED-mail map of Bolivia:
<http://healthmap.org/promed/p/10123>]
Date: Mon 1 Jul 2019
Source: Eje Central Mexico [in Spanish, trans. ProMED Mod.MPP, edited]
<http://www.ejecentral.com.mx/alertan-por-enfermedad-viral-no-identificada-en-bolivia/>

An unknown disease that led to the death of an internal medicine physician and that has another 2 in serious condition has led to the activation of health protocols in Bolivia, requesting assistance from international medical teams in order to identify the aetiology of the disease, it was announced on Mon 1 Jul 2019 by the Minister of Health, Gabriela Montano.

Initial diagnostic tests indicated a "viral disease," but through the analysis of the physician who died and the 2 other professionals who are in intensive care, "they have discarded influenza and other viral diseases," such as dengue, according to Montano.

In the last hours, Montano increased the number of infected individuals to 5.  "We have 3 suspected cases in addition to the 1st 2 cases, the doctors; the other 3 are in the same hospital (in La Paz) as the original 2 cases," the Minister of Health said at a press conference.  "Two of the 3 new cases had contact with the 2 doctors who were infected. The 3rd person did not have contact with the professionals, but presented similar symptoms," said Montano.

In order to establish the origin of the disease, an infectious disease specialist from Brasil and another 2 specialists from Atlanta, United States [the Centers for Disease Control and Prevention, CDC], will help the national teams in the investigation.  The health authorities have not declared a state of epidemiologic emergency, while the representative from the Pan American Health Organization [PAHO/OPS] in Bolivia, Alfonso Tenorio, asked to follow protocols in order to "be calm."  "Bolivia has "the equipment and personnel fully trained in order to take the appropriate diagnostic steps, treatment, clinical management, and epidemiologic control," said Tenorio at a press conference.

As part of these protocols, the Ministry of Health ordered the mandatory use of masks and latex gloves in local hospitals.  At the end of last year [2018], Caranavi, the semitropical zone in the northeast of La Paz, where the deceased doctor was infected, reported a dengue outbreak that claimed the lives of 5 people.
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