All there is to know about hantavirus


In recent weeks (December 2018 to January 2019) an unusual outbreak of hantavirus is developing in Argentina, whose only antecedent is El Bolsón in 1996. Inter-human transmission is suspected as the main mode of infection. This is indicated by a report from the Argentine Society of Infectious Diseases (SADI).

On November 14, 2018, a case was identified by hantavirus in Epuyén (Chubut) with an epidemiological link of environmental exposure. On November 3, the patient attended a social event and 5 participants had hantavirus with onset of symptoms in the following weeks. As of January 10, about 25 cases were reported and a dozen deaths, all contacts from other cases. Even a person of Chilean nationality who had been connected to the event died.

In Argentina there are two Hanta virus species (Andes and Laguna Negra) and at least 10 different viral genotypes, 8 of which were associated with hantavirus cardiopulmonary syndrome (SCPH). Susana López de Caillou, head of the chair of virology at the Faculty of Biochemistry at the National University of Tucumán, Argentina, said that because of the wide distribution and dynamics of reservoirs (long-tailed rats) and human intervention in wild habitats, conditions for the disease to occur in other provinces. "

The risk areas of the SCPH in Argentina are: 1) Northwest, which coincides with the ecoregion of the Yungas and, to a lesser degree, with the Chaco Seco; 2) Northeast, which encompasses the missionary forest; 3) The Pampas region and the Paraná delta; and 4) The Valdivian forest in the Patagonian foothills.

[Img #54174]

Hantavirus disease is commonly transmitted to humans by wild rodents. (Photo: Argentina investigates)

In an interview conducted by Argentina Investiga, the virologist Susana López de Caillou explained several questions about the cases registered in Argentina, intra-human transmission and preventive measures.

Studies by the Universidad Austral de Chile in 2006 already describe that some genotypes of the Andes virus can be stored in salivary glands and other body fluids such as human semen, allowing inter-human transmission. IntraMed Magazine highlights that what led the scientific community to accept that there is contagion among the people was the case of an Argentine who in 1997 fell ill in Bariloche. After traveling to Buenos Aires, he infected another 16 people who were not exposed to mouse feces, and even the doctor who treated the patient died of Hanta.

Precisely that & # 39; Andes Virus & # 39; is the only genotype that has the inter-human transmissibility factor, according to the international bibliography. If it turns out that the genomic sequence of the virus in all infected Epuyén is the same, it will become the outbreak by inter-human transmission with the largest number of affected in the world. In other regions of the planet, Hanta has not been described with these transmission characteristics.

López de Caillou said there is evidence of person-to-person transmission and therefore secretions like saliva and other human fluids "should be considered potentially dangerous." However, the professional established the difference of the hantavirus genotypes that circulate in the north because they have not been shown to be transmissible among people, unlike the Andes genotype.

Between 2013 and 2018, 111 confirmed confirmed cases of hantavirus were reported in Argentina with a lethality rate of 18.6%, with lethality in some provinces in the southern region of the country close to 40%. This is according to the records of the National Health Surveillance System. The Pan American Health Organization reported 1,350 cases of this disease in Argentina from 1995 to December 2016.

Hantavirus is an emerging zoonosis produced by RNA viruses belonging to the Bunyaviridae family. Viruses have a worldwide distribution and produce in humans two serious clinical forms, Hemorrhagic Fever with Renal Syndrome in Asia and Europe and Hantavirus Cardiopulmonary Syndrome in America. It is transmitted to humans by wild rodents. These animals present asymptomatic chronic infection with blood virus, persistently and eliminate the virus through urine, saliva and excreta. In particular, it is transmitted by the mouse or long-tailed, belonging to the families Muridae / Cricetidae (wild and nocturnal habits).

Hantaviruses are transmitted primarily by inhalation of aerosols loaded with viral particles from the feces, urine and saliva of infected rodents. Other possible routes of transmission are: contact with excrements or secretions of mice infected with the conjunctival, nasal or buccal mucosa, or bite of the infected rodent.

Transmission to humans generally occurs when entering rodent habitat in suburban and rural environments, especially in the peridomestic and during the development of work, recreational activities or indoors, such as sheds or deposits infested by rodents.

The other form of transmission that until now has only occurred in Argentina is from person to person, a modality that is being studied by researchers from that country and Chile.

Regarding the symptoms, the hantavirus cardiopulmonary syndrome may present as a mild condition, with a nonspecific febrile syndrome or reach a more severe manifestation with severe respiratory insufficiency and cardiogenic shock.

The first symptoms are similar to a flu state: fever of 38 degrees Celsius, muscle aches, chills, headache, nausea, vomiting, abdominal pain, diarrhea without compromising the upper airways.

The incubation time usually has the virus is usually between 15 and 20 days, although it may appear after a few days or extend for up to 40 days, according to some cases reported.

In terms of how to prevent infection, these are the main preventive measures:
– Avoid coexistence with rodents and contact with their secretions.
– Cover holes in doors, walls and pipes.
– Perform the cleaning (floors, walls, doors, tables, drawers and cabinets) with one part of bleach every nine of water (leave 30 minutes and then rinse). Moisten the floor before sweeping to avoid dust.
– Put gardens and firewood more than 30 meters from the houses, cut grass and weeds up to a radius of 30 meters around the house.
– Ventilate at least 30 minutes before entering enclosed places (houses, sheds). Cover your mouth and nose with a damp cloth before entering or breathing in the mask.
– Take special care in the commissioning of fans and air conditioners whose filters or ducts may have come into contact with contaminated dust, rodents or excreta.
– When camping with weeds and dumps, do not sleep directly on the ground and consume drinking water.
– If a live rodent is found: use poison for rodents or hunters to catch it (do not try to touch it or hit it). Check with the county if a pest control service is available.
– If a dead rodent is found: spray with bleach along with everything that could be in contact and wait at least 30 minutes. Then take it with gloves and bury it more than 30 cm deep or burn it.
– People who have symptoms of the disease should go to a health center quickly for consultation and avoid close contact with other people.

(Source: Daniela Orlandi / Argentina Investigates)


Source link