May 14, 2019 – 10:13 am
The virus Mayaro, discovered in the 1950s on the Caribbean island of Trinidad, the largest island of the Republic of Trinidad and Tobago, is attracting the attention of tropical medicine specialists due to the confluence of factors that it can spread in regions of America. America where he hasn't arrived yet.
Until recently it was believed that the virus, related to the virus that causes the feverchikungunya, was transmitted only by mosquitoes of the genus Haemagogus, which has its habitat, especially in the jungle areas of Central and South America.
"But it is now known that it is also transmitted by Aedes aegypti, a large-spread insect in Argentina and other countries, which entails a certain risk that this pathogen will continue to expand its endemic zone and even hit areas where it has not yet been spread," said Dr. Antonio Montero, scientific director of the Center for Tropical Medicine and Emerging Infectious Diseases of the Faculty of Medical Sciences of the National University of Rosario (UNR).
Montero described this problem in an article that was published in the magazine in April Austin Journal of Tropical Medicine & Hygiene. Since the first description in Trinidad and northern Brazil, the Mayaro virus has spread to most of the Amazon rainforest, with sporadic cases or minor epidemics in Bolivia, Colombia, French Guiana, Peru, Venezuela, Haiti and Suriname. On the other hand, blood tests from patients reveal exposure to this pathogen in residents of Costa Rica, Guatemala and Panama, Mexico and Northern Argentina.
Mayaro produces an image very similar to chikungunya fever, the symptoms of which are often confused with those of dengue fever. "In addition to fever and rash (skin rash), this virus causes symptoms," said Montero.
The Mayaro virus is relatively harmless because of the low mortality. But Monterono wants to lower his surveillance. "It is still unknown whether this pathogen is capable, as in the case of the Zika virus, of causing fetal malformations or increasing fetal mortality. It is also not known whether it affects the central nervous system and whether it is in this case can leave sequels. It is necessary to conduct studies to determine it, "he said.
There are two conditions that limit the spread of the virus: it survives a short time in the blood of patients and the viremia (blood concentration) is of low intensity. "However, any factor that changes these conditions, such as a viral mutation or a longer period of interaction between sensitive hosts (humans or animals) and mosquitoes, can start an epidemic of proportions, as has happened in some cities," the expert said. .
Another drawback is that the Mayaro virus is also able to infect birds, to the point that it has been identified in migratory birds caught as far away as Salt Lake City in the United States. "This fact gives rise to the alarming possibility that birds can introduce the virus to remote areas through the bite of Aedes sex mosquitoes," said the UNR scientist.
Mass tourism is another factor in the "transport" of the virus. Travelers who have returned from France and the Netherlands from endemic areas have contracted the virus according to their blood tests.
"Since this viral agent has the potential to cause major epidemics or even a pandemic, and we are convinced that this will happen sooner or later, we consider it particularly important that the health authorities of the region and our country activate control systems to: to take appropriate prevention and control measures, »warned Montero.
Dr. Tomás Orduna, doctor for tropical infectious diseases and head of the Regional Pathology and Tropical Medicine department of the Francisco J. Muñiz infectious hospital in Buenos Aires, confirmed that this virus is under surveillance in Argentina. "It's a pathogen that we consider and that is included in the differential diagnosis of undifferentiated or non-specific febrile syndrome," he said.
He also confirmed the need to increase surveillance measures in the region of both the Mayaro virus and other arboviruses (pathogens transmitted by arthropods, usually insects). Five years ago we had no Zika and chikungunya on our continent, which are pathogenic that came from Africa. For more reason, we need to monitor the working conditions viruses we have within our region, "he said.
In this line, the Muñiz specialist said that there are dozens of little-known arboviruses in the Amazon and other tropical and sub-tropical areas that usually circulate between mosquitoes, monkeys and other animals and that must be kept under control, such as the Oropouche virus.
According to Orduna, which also integrates the Argentine Society of Infectious Disease (SADI) and the Latin American Society of Traveler Medicine (SLAMVI), urban vectors should be checked, their contact with people should be limited, medical staff should be better trained, laboratories in the region with sophisticated techniques of molecular biology to identify viruses in blood samples, and above all "perform an early consultation if you have a fever, especially when you have been in endemic areas."