Hantavirus pulmonary syndrome (HPS) is one of two potentially fatal

syndrome A syndrome is a set of medical signs and symptoms which are correlated with each other and often associated with a particular disease or disorder. The word derives from the Greek language, Greek σύνδρομον, meaning "concurrence". When a sy ...

s of zoonotic origin caused by species of hantavirus. These include Black Creek Canal virus (BCCV),

New York orthohantavirus New York orthohantavirus or New York virus is an ''Orthohantavirus''. It is considered a strain of ''Sin Nombre orthohantavirus''. It was first isolated from a white-footed mouse (''Peromyscus leucopus'') caught on an island off New York. The ...

(NYV),

Monongahela virus Monongahela virus (MGLV) is a single-stranded, negative-sense ''Orthohantavirus'' virus of zoonotic origin that causes hantavirus pulmonary syndrome. Discovery of virus Monongahela virus was first detected in '' Peromyscus maniculatus nubiterr ...

(MGLV), ''

Sin Nombre orthohantavirus ''Sin Nombre orthohantavirus'' (SNV) (from Spanish, meaning "without a name") is the prototypical etiologic agent of hantavirus cardiopulmonary syndrome (HCPS). Discovered in 1993 near the Cañon de la Muerte on the Navajo Reservation, it was o ...

'' (SNV), and certain other members of hantavirus genera that are native to the United States and Canada. Specific

rodent Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are n ...

s are the principal hosts of the hantaviruses including the

hispid cotton rat The hispid cotton rat (''Sigmodon hispidus'') is a rodent species long thought to occur in parts of South America, Central America, and southern North America. However, recent taxonomic revisions, based on mitochondrial DNA sequence data, ha ...

(''Sigmodon hispidus'') in

southern Florida South Florida is the southernmost region of the U.S. state of Florida. It is one of Florida's three most commonly referred to directional regions; the other two are Central Florida and North Florida. South Florida is the southernmost part of ...

, which is the principal host of Black Creek Canal virus. The deer mouse (''Peromyscus maniculatus'') in

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by to ...

and the

Western United States The Western United States (also called the American West, the Far West, and the West) is the region comprising the westernmost states of the United States. As American settlement in the U.S. expanded westward, the meaning of the term ''the We ...

is the principal host of Sin Nombre virus. The white-footed mouse (''Peromyscus leucopus'') in the eastern United States is the principal host of New York virus. In

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sou ...

, the long-tailed mouse (''

Oligoryzomys longicaudatus ''Oligoryzomys longicaudatus'', also known as the long-tailed colilargo or long-tailed pygmy rice rat, is a species of rodent in the genus ''Oligoryzomys'' of the family Cricetidae. It is found in the southern Andes of Chile and Argentina, with ...

'') and other species of the genus ''

Oligoryzomys ''Oligoryzomys'' is a genus of rodents in the tribe Oryzomyini of family Cricetidae. Many species are known as pygmy rice rats or colilargos.Musser and Carleton, 2005 The genus is found from Mexico to Tierra del Fuego and includes approximately 1 ...

'' have been documented as the reservoir for Andes virus.

Signs and symptoms

Initially, HPS has an incubation phase of 2–4 weeks, in which patients remain asymptomatic. Subsequently, patients can experience 3–5 days of flu-like prodromal phase symptoms, including

fever Fever, also referred to as pyrexia, is defined as having a temperature above the normal range due to an increase in the body's temperature set point. There is not a single agreed-upon upper limit for normal temperature with sources using val ...

, cough, muscle pain, headache, lethargy,

shortness of breath Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing di ...

, nausea, vomiting and diarrhea. In the following 5–7 day cardiopulmonary phase, the patient's condition rapidly deteriorates into acute

respiratory failure Respiratory failure results from inadequate gas exchange by the respiratory system, meaning that the arterial oxygen, carbon dioxide, or both cannot be kept at normal levels. A drop in the oxygen carried in the blood is known as hypoxemia; a rise ...

, characterized by the sudden onset of shortness of breath with rapidly evolving

pulmonary edema Pulmonary edema, also known as pulmonary congestion, is excessive liquid accumulation in the tissue and air spaces (usually alveoli) of the lungs. It leads to impaired gas exchange and may cause hypoxemia and respiratory failure. It is due ...

, as well as

cardiac failure Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, ...

, with hypotension, tachycardia and shock. In this phase, patients may develop

acute respiratory distress syndrome Acute respiratory distress syndrome (ARDS) is a type of respiratory failure characterized by rapid onset of widespread inflammation in the lungs. Symptoms include shortness of breath (dyspnea), rapid breathing (tachypnea), and bluish skin colo ...

. It is often fatal despite

mechanical ventilation Mechanical ventilation, assisted ventilation or intermittent mandatory ventilation (IMV), is the medical term for using a machine called a ventilator to fully or partially provide artificial ventilation. Mechanical ventilation helps move a ...

and intervention with

diuretic A diuretic () is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. A diuretic tablet is sometimes colloquially called a water tablet. There are several categories of diuretics. All diuretics i ...

s. After the cardiopulmonary phase, patients can enter a diuretic phase of 2–3 days characterized by symptom improvement and

diuresis Diuresis () is increased urination (polyuria) or, in the related word senses more often intended, the physiological process that produces such an increase or the administration of medications to encourage that process. It involves extra urine pr ...

. Subsequent

convalescence Convalescence is the gradual recovery of health and strength after illness or injury. It refers to the later stage of an infectious disease or illness when the patient recovers and returns to previous health, but may continue to be a source of ...

can last months to years. As of 2017, patient mortality in the US from HPS is 36%.

Transmission

The virus can be transmitted to humans by a direct bite or inhalation of aerosolized virus, shed from stool, urine, or saliva from a natural reservoir rodent. In general, droplet and/or

fomite A fomite () or fomes () is any inanimate object that, when contaminated with or exposed to infectious agents (such as pathogenic bacteria, viruses or fungi), can transfer disease to a new host. Transfer of pathogens by fomites A fomite is any ...

transfer has not been shown in the hantaviruses in either the pulmonary or hemorrhagic forms.

Diagnosis

The preferred method for diagnosis of Hantavirus Pulmonary Syndrome is serological testing which identifies both acute (IgM) and remote infections (IgG); however, PCR may also be used to identify early infections.

Prevention

Rodent control in and around the home or dwellings remains the primary prevention strategy, as well as eliminating contact with rodents in the workplace and at campsites. Closed storage sheds and cabins are often ideal sites for rodent infestations. Airing out of such spaces prior to use is recommended. People are advised to avoid direct contact with rodent droppings and wear a mask while cleaning such areas to avoid inhalation of aerosolized rodent secretions.

Treatment

There is no cure or vaccine for HPS. Treatment involves supportive therapy, including

with supplemental oxygen during the critical respiratory-failure stage of the illness. Although

ribavirin Ribavirin, also known as tribavirin, is an antiviral medication used to treat RSV infection, hepatitis C and some viral hemorrhagic fevers. For hepatitis C, it is used in combination with other medications such as simeprevir, sofosbuvir, pe ...

can be used to treat hantavirus infections, it is not recommended as a treatment for HPS due to unclear clinical efficacy and likelihood of medication side effects. Early recognition of HPS and admission to an intensive care setting offers the best

prognosis Prognosis ( Greek: πρόγνωσις "fore-knowing, foreseeing") is a medical term for predicting the likely or expected development of a disease, including whether the signs and symptoms will improve or worsen (and how quickly) or remain sta ...

Epidemiology

Hantavirus pulmonary syndrome was first recognized during the 1993 outbreak in the

Four Corners The Four Corners is a region of the Southwestern United States consisting of the southwestern corner of Colorado, southeastern corner of Utah, northeastern corner of Arizona, and northwestern corner of New Mexico. The Four Corners area ...

region of the

southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, N ...

. It was identified by Dr. Bruce Tempest. It was originally called Four Corners disease, but the name was changed to Sin Nombre virus after complaints by Native Americans that the name "Four Corners" stigmatized the region. It has since been identified throughout the United States.

References

External links

"Hantaviruses, with emphasis on Four Corners Hantavirus"
by Brian Hjelle, M.D., 2001, Department of Pathology, School of Medicine, University of New Mexico

US Center for Disease Control

Virus Pathogen Database and Analysis Resource (ViPR): Bunyaviridae

PAHO {{Authority control Viral respiratory tract infections Hantavirus infections Rodent-carried diseases Biological weapons Syndromes caused by microbes Zoonoses