Researchers from the U.S. Centers for Disease Control and Prevention (CDC) have unveiled new clues about the many mysteries surrounding the Chapare virus, which caused at least five infections near Bolivia’s capital La Paz in 2019. , three of them fatal.
Bolivia, November 19 (Europa Press) .– The researchers have discovered that a mortal virus what has been detected in Bolivia may spread person to person in healthcare settings, resulting in potential concerns of additional outbreaks in the future, according to new findings presented Monday at the American Society for Tropical Medicine and Hygiene (ASTMH) meeting.
The investigation also provides evidence preliminary regarding the species of rodent which carries the virus and you can transmit it to people or other animals that can infect humans.
Researchers from the United States Centers for Disease Control and Prevention (CDC) have presented new clues about the many mysteries surrounding the Chapare virus, that caused at least five infections near Bolivia’s capital La Paz in 2019, three of them fatal.
Before that, the only record of the disease was a small group and a single confirmed case in 2004 in the Chapare province of Bolivia. The recent outbreak surprised health authorities, as they initially only knew that it was a hemorrhagic fever that produced symptoms similar to diseases such as Ebola.
“Our work confirmed that a young resident physician, an ambulance physician, and a gastroenterologist contracted the virus after encountering infected patients, and two of these healthcare workers later died,” says Caitlin Cossaboom, epidemiologist with the Division of Pathogens and Consequential Pathology. CDC Discharge – We now believe that many bodily fluids can potentially carry the virus. “
Cossaboom explains that confirmation of person-to-person transmission shows that healthcare providers and anyone else dealing with suspected cases must exercise extreme care to avoid contact with items that may be contaminated with blood, urine, saliva, or semen.
Chapare belongs to a group of viruses called arenaviruses. Among them are dangerous pathogens such as the Lassa virus, which causes thousands of deaths a year in West Africa, and the Machupo virus, which has caused deadly outbreaks in Bolivia.
Like those pathogens, the Chapare virus can cause hemorrhagic fevers, a condition that is also seen in Ebola patients and can lead to serious problems in various organs, causing patients to struggle to survive.
Cossaboom notes that patients of the 2019 Chapare outbreak suffered from fever, abdominal pain, vomiting, bleeding gums, a skin rash, and pain behind the eyes.
There is no specific treatment, so patients are treated primarily with intravenous fluids and other supportive care.
There is still much that is unknown about the Chapare virus, mainly where it originated, how it infects humans, and the likelihood of larger outbreaks in Bolivia and other parts of South America.
Cossaboom now presents new evidence of Chapare viral RNA detected in rodents collected from an area around the home and nearby farmland of the first patient identified in the 2019 outbreak: a farm worker who also died.
He cautions that the evidence falls short of proving that rodents were the source of their infection (viral RNA is not proof that rodents were infectious), although it offers an important clue.
“The sequence of the RNA genome that we isolated in rodent samples coincides quite well with what we have seen in human cases,” he adds.
Rodent species that tested positive for viral RNA are found in Bolivia and several neighboring countries. Rodents are a key source or reservoir of similar viruses, including the Lassa virus.
Scientists believe that the Chapare virus could have been circulating in Bolivia for several years, but infected patients may have been misdiagnosed with dengue, a disease that is common in the region and can produce similar symptoms.
Cossaboom’s colleague at the CDC, Maria Morales-Betoulle, describes intensive work carried out by Bolivian health officials in La Paz, scientists from the Bolivian Center for Tropical Diseases (CENETROP) in Santa Cruz de la Sierra, PAHO colleagues, and experts in infectious diseases at CDC headquarters in Atlanta to control the 2019 outbreak.
He adds that when it became clear that the disease was not caused by dengue, patient samples collected by Bolivian authorities were quickly sent to a high-security CDC biosafety level 4 (BSL-4) laboratory. Once there, they were subjected to analysis with advanced next-generation genome sequencing technology.
CDC experts were able to identify the virus as Chapare because it matched sequence data derived from the patient involved in the original 2004 infection.
“We isolated the virus and expected to find a more common disease, but the sequence data pointed to the Chapare virus,” Morales-Betoulle says. We were very surprised because the 2019 outbreak in La Paz occurred long after the first case was identified in 2004 ”.
It adds that the availability of new sequencing tools allowed CDC experts to rapidly develop an RT-PCR test to detect Chapare, the same type of test often used to diagnose COVID-19, which is considered the standard for gold for him
The research then moved to CENETROP in Santa Cruz de la Sierra, where there is a BSL-3 laboratory and a team capable of obtaining and analyzing patient samples.
Several collaborators of the team were already in South America investigating other viral hemorrhagic fevers when the 2019 outbreak occurred. “That allowed us to mobilize and move very quickly,” he celebrates.
Morales-Betoulle and Cossaboom note that future work will focus on the use of diagnostic tests to conduct surveillance to identify additional human infections and field work to determine whether rodents are involved in the spread of the disease.
Since the outbreak, CENETROP has identified three additional suspected cases, including one involving a child. All are believed to have survived.
“While much is still unknown about the Chapare virus, the speed with which this team was able to develop a diagnostic test, confirm human-to-human transmission and discover preliminary evidence of the virus in rodents is commendable,” admits the president ASTMH, Joel Breman–. It is a valuable lesson that international scientific teams, equipped with the latest tools and freely sharing their knowledge, are our best front-line defense against the disruptive threats of deadly infectious diseases. “