Typhus, also known as typhus fever, is a group of infectious diseases that include epidemic typhus, scrub typhus and murine typhus. Common symptoms include fever, headache, and a rash. Typically these begin one to two weeks after exposure.
The diseases are caused by specific types of bacterial infection. Epidemic typhus is due to Rickettsia prowazekii spread by body lice, scrub typhus is due to Orientia tsutsugamushi spread by chiggers, and murine typhus is due to Rickettsia typhi spread by fleas.
There is currently no commercially available vaccine. Prevention is by reducing exposure to the organisms that spread the disease. Treatment is with the antibiotic doxycycline. Epidemic typhus generally occurs in outbreaks when poor sanitary conditions and crowding are present. While once common, it is now rare. Scrub typhus occurs in Southeast Asia, Japan, and northern Australia. Murine typhus occurs in tropical and subtropical areas of the world.
Typhus has been described since at least 1528 AD. The name comes from the Greek tûphos (τύφος) meaning hazy, describing the state of mind of those infected. While "typhoid" means "typhus-like", typhus and typhoid fever are distinct diseases caused by different types of bacteria.
|Other names||Typhus fever|
|Rash caused by epidemic typhus|
|Symptoms||Fever, headache, rash|
|Usual onset||1–2 weeks after exposure|
|Causes||Bacterial infection spread by parasites|
The following signs and symptoms refer to epidemic typhus as it is the most important of the typhus group of diseases.
Signs and symptoms begin with sudden onset of fever, and other flu-like symptoms about one to two weeks after being infected. Five to nine days after the symptoms have started, a rash typically begins on the trunk and spreads to the extremities. This rash eventually spreads over most of the body, sparing the face, palms, and soles. Signs of meningoencephalitis begin with the rash and continue into the second or third weeks. Other signs of meningoencephalitis include sensitivity to light (photophobia), altered mental status (delirium), or coma. Untreated cases are often fatal.
Multiple diseases include the word "typhus" in their description. Types include:
|Epidemic louse-borne typhus||Rickettsia prowazekii||Body louse||When the term "typhus" is used without clarification, this is usually the condition described. Historical references to "typhus" are now generally considered to be this condition.|
|Murine typhus or "endemic typhus"||Rickettsia typhi||Fleas on rats|
|Scrub typhus||Orientia tsutsugamushi||Harvest mites on humans or rodents|
|Queensland tick typhus or "Australian tick typhus" (and a spotted fever)||Rickettsia australis||Ticks|
The American Public Health Association recommends treatment based upon clinical findings and before culturing confirms the diagnosis. Without treatment, death may occur in 10 to 60 percent of patients with epidemic typhus, with patients over age 60 having the highest risk of death. In the antibiotic era, death is uncommon if doxycycline is given. In one study of 60 hospitalized patients with epidemic typhus, no patient died when given doxycycline or chloramphenicol. Some patients also may need oxygen and intravenous (IV) fluids.
Only a few areas of epidemic typhus exist today. Since the late 20th century, cases have been reported in Burundi, Rwanda, Ethiopia, Algeria, and a few areas in South and Central America.
Except for two cases, all instances of epidemic typhus in the United States have occurred east of the Mississippi River. An examination of a cluster of cases in Pennsylvania concluded the source of the infection was flying squirrels. Sylvatic cycle (diseases transmitted from wild animals) epidemic typhus remains uncommon in the US. The Centers for Disease Control and Prevention have documented only 47 cases from 1976 to 2010. An outbreak of flea-borne typhus was identified in downtown Los Angeles, California in October 2018 that was larger than their usual number of typhus cases.
The first reliable description of the disease appears in 1489 AD during the Spanish siege of Baza against the Moors during the War of Granada (1482–1492). These accounts include descriptions of fever; red spots over arms, back, and chest; attention deficit, progressing to delirium; as well as gangrenous sores and the associated smell of rotting flesh. During the siege, the Spaniards lost 3,000 men to enemy action, but an additional 17,000 died of typhus. 
In historical times "Gaol Fever", or "Aryotitus fever" was common in English prisons, and is believed by modern authorities to have been typhus. It often occurred when prisoners were crowded together into dark, filthy rooms where lice spread easily. Thus "Imprisonment until the next term of court" was often equivalent to a death sentence. Prisoners brought before the court sometimes infected members of the court. Following the assizes held at Oxford in 1577, later deemed the Black Assize, over 300 died from gaol fever, including Sir Robert Bell, Lord Chief Baron of the Exchequer. The Black Assize of Exeter 1586 was another notable outbreak. During the Lent assizes court held at Taunton in 1730, gaol fever caused the death of the Lord Chief Baron, as well as the High Sheriff, the sergeant, and hundreds of others. During a time when persons were executed for capital offenses, more prisoners died from 'gaol fever' than were put to death by all the public executioners in the British realm. In 1759, an English authority estimated that each year a quarter of the prisoners had died from gaol fever. In London, gaol fever frequently broke out among the ill-kept prisoners of Newgate Prison and then moved into the general city population. In May 1750, the Lord Mayor of London, Sir Samuel Pennant, and a large number of court personnel were fatally infected in the courtroom of the Old Bailey, which adjoined Newgate Prison.
Epidemics occurred routinely throughout Europe from the 16th to the 19th centuries, including during the English Civil War, the Thirty Years' War, and the Napoleonic Wars. Pestilence of several kinds raged among combatants and civilians in Germany and surrounding lands from 1618 to 1648. According to Joseph Patrick Byrne, "By war's end, typhus may have killed more than 10 percent of the total German population, and disease in general accounted for 90 percent of Europe's casualties."
A major epidemic occurred in Ireland between 1816 and 1819, during the famine caused by a worldwide reduction in temperature known as the Year Without a Summer. An estimated 100,000 people perished. Typhus appeared again in the late 1830s, and yet another major typhus epidemic occurred during the Great Irish Famine between 1846 and 1849. The Irish typhus spread to England, where it was sometimes called "Irish fever" and was noted for its virulence. It killed people of all social classes, as lice were endemic and inescapable, but it hit particularly hard in the lower or "unwashed" social strata.
In the United States, a typhus epidemic broke out in Philadelphia in 1837 and killed the son of Franklin Pierce (14th President of the United States) in Concord, New Hampshire, in 1843. Several epidemics occurred in Baltimore, Memphis and Washington, D.C. between 1865 and 1873. Typhus was also a significant killer during the US Civil War, although typhoid fever was the more prevalent cause of US Civil War "camp fever". Typhoid fever, caused by the bacterium Salmonella typhii (not to be confused with Salmonella enterica, the cause of salmonella food poisoning), is a completely different disease from typhus.
In Canada alone, the typhus epidemic of 1847 killed more than 20,000 people from 1847 to 1848, mainly Irish immigrants in fever sheds and other forms of quarantine, who had contracted the disease aboard the crowded coffin ships in fleeing the Great Irish Famine. Officials neither knew how to provide sufficient sanitation under conditions of the time nor understood how the disease spread.
The clipper Ticonderoga was infamous for her "fever ship" voyage from Liverpool to Port Phillip carrying 795 passengers in 1852. The overcrowded ship was not designed well for passenger carrying, sanitary provisions were inadequate, and the ship's doctors were soon overwhelmed. During the voyage, 100 passengers died of what was later determined to have been typhus.
Delousing stations were established for troops on the Western Front during World War I, but the disease ravaged the armies of the Eastern Front, with over 150,000 dying in Yugoslavia alone. Fatalities were generally between 10 and 40 percent of those infected, and the disease was a major cause of death for those nursing the sick.
In 1922, the typhus epidemic reached its peak in Soviet territory, with some 25 to 30 million cases in Russia. Although typhus had ravaged Poland with some 4 million cases reported, efforts to stem the spread of disease in that country had largely succeeded by 1921 through the efforts of public health pioneers such as Hélène Sparrow and Rudolf Weigl. In Russia, during the civil war between the White and Red Armies, typhus killed 3 million people, mainly civilians.
During World War II, many German POWs after the loss at Stalingrad died of typhus. Typhus epidemics killed those confined to POW camps, ghettos, and Nazi concentration camps who were held in unhygienic conditions. Pictures of mass graves including people who died from typhus can be seen in footage shot at Bergen-Belsen concentration camp.
Among thousands of prisoners in concentration camps such as Theresienstadt and Bergen-Belsen who died of typhus were Anne Frank, age 15, and her sister Margot, age 19. Major epidemics in the post-war chaos of Europe were averted only by widespread use of the newly discovered DDT to kill the lice on millions of refugees and displaced persons.
The first typhus vaccine was developed by the Polish zoologist Rudolf Weigl in the interwar period. Better, less-dangerous and less-expensive vaccines were developed during World War II. Since then, some epidemics have occurred in Asia, Eastern Europe, the Middle East, and parts of Africa.
Beginning in 2018, a typhus outbreak of more than the usual number of cases has spread through Los Angeles County primarily affecting homeless people. In 2019 city attorney Elizabeth Greenwood revealed that she too was infected with typhus as a result of a flea bite at her office in Los Angeles City Hall which resulted in her going on medical leave.
Bolivian hemorrhagic fever (BHF), also known as black typhus or Ordog Fever, is a hemorrhagic fever and zoonotic infectious disease originating in Bolivia after infection by Machupo mammarenavirus.BHF was first identified in 1963 as an ambisense RNA virus of the Arenaviridae family, by a research group led by Karl Johnson. The mortality rate is estimated at 5 to 30 percent. Due to its pathogenicity, Machupo virus requires Biosafety Level Four conditions, the highest level.During the period between February and March 2007, some 20 suspected BHF cases (3 fatal) were reported to the El Servicio Departamental de Salud (SEDES) in Beni Department, Bolivia. In February 2008, at least 200 suspected new cases (12 fatal) were reported to SEDES. In November 2011, a second case was confirmed near the departmental capital of Trinidad, and a serosurvey was conducted to determine the extent of Machupo virus infections in the Department. A SEDES expert involved in the survey expressed his concerns about the expansion of the virus to other provinces outside the endemic regions of Mamoré and Iténez provinces.Boutonneuse fever
Boutonneuse fever (also called Mediterranean spotted fever, fièvre boutonneuse, Kenya tick typhus, Indian tick typhus, Marseilles fever, or African tick-bite fever, or Astrakhan Fever) is a fever as a result of a rickettsial infection caused by the bacterium Rickettsia conorii and transmitted by the dog tick Rhipicephalus sanguineus. Boutonneuse fever can be seen in many places around the world, although it is endemic in countries surrounding the Mediterranean Sea. This disease was first described in Tunisia in 1910 by Conor and Bruch and was named boutonneuse (French for "spotty") due to its papular skin rash characteristics.Brill–Zinsser disease
Brill–Zinser disease is a delayed relapse of epidemic typhus, caused by Rickettsia prowazekii. After a patient contracts epidemic typhus from the fecal matter of an infected louse (Pediculus humanus), the rickettsia can remain latent and reactivate months or years later, with symptoms similar to or even identical to the original attack of typhus, including a maculopapular rash. This reactivation event can then be transmitted to other individuals through fecal matter of the louse vector, and form the focus for a new epidemic of typhus.Epidemic typhus
Epidemic typhus is a form of typhus so named because the disease often causes epidemics following wars and natural disasters. The causative organism is Rickettsia prowazekii, transmitted by the human body louse (Pediculus humanus corporis).Flying squirrel typhus
Flying squirrel typhus is a condition characterized by a rash of early macules, and, later, maculopapules.The flying squirrel Glaucomys volans can transmit epidemic typhus.Apart from humans, flying squirrels are the only currently known reservoir for Rickettsia prowazekii.Gammaproteobacteria
Gammaproteobacteria are a class of bacteria. Several medically, ecologically, and scientifically important groups of bacteria belong to this class. Like all Proteobacteria, the Gammaproteobacteria are Gram-negative.Murine typhus
Murine typhus (also called endemic typhus) is a form of typhus transmitted by fleas (Xenopsylla cheopis), usually on rats. (This is in contrast to epidemic typhus, which is usually transmitted by lice.) Murine typhus is an under-recognized entity, as it is often confused with viral illnesses. Most people who are infected do not realize that they have been bitten by fleas.North Asian tick typhus
North Asian tick typhus (or North Asian tick fever), also known as Siberian tick typhus, is a condition characterized by a maculopapular rash.It is associated with Rickettsia sibirica.Queensland tick typhus
Queensland tick typhus (or Australian tick typhus or (Rickettsial) spotted fever) is a condition caused by a bacterium Rickettsia australis.It is transmitted by Ixodes holocyclus and Ixodes tasmani.Rickettsia
Rickettsia is a genus of nonmotile, Gram-negative, non-spore-forming, highly pleomorphic bacteria that may occur in the forms of cocci 0.1 μm in diameter, rods 1–4 μm long, or threads of up to about 10 μm long. The term "rickettsia" has nothing to do with rickets, which is a deficiency disease resulting from lack of vitamin D; the bacterial genus Rickettsia was named after Howard Taylor Ricketts, in honour of his pioneering work on tick-borne spotted fever.
Properly, Rickettsia is the name of a single genus, but the informal term "rickettsia", plural "rickettsias", usually non-capitalised, commonly applies to any members of the order Rickettsiales. Being obligate intracellular parasites, rickettsias depend on entry, growth, and replication within the cytoplasm of living eukaryotic host cells (typically endothelial cells). Accordingly Rickettsia species cannot grow in artificial nutrient culture; they must be grown either in tissue or embryo cultures; typically, chicken embryos are used, following a method developed by Ernest William Goodpasture and his colleagues at Vanderbilt University in the early 1930s.
Rickettsia species are transmitted by numerous types of arthropod, including chigger, ticks, fleas, and lice, and are associated with both human and plant disease. Most notably, Rickettsia species are the pathogens responsible for typhus, rickettsialpox, Boutonneuse fever, African tick bite fever, Rocky Mountain spotted fever, Flinders Island spotted fever and Queensland tick typhus (Australian tick typhus). The majority of Rickettsia bacteria are susceptible to antibiotics of the tetracycline group.Rickettsia conorii
Rickettsia conorii is a Gram-negative, obligate intracellular bacterium of the genus Rickettsia that causes human disease called Boutonneuse fever, Mediterranean spotted fever, Israeli tick typhus, Astrakhan spotted fever, Kenya tick typhus, Indian tick typhus, or other names that designate the locality of occurrence while having distinct clinical features. It is a member of the spotted fever group and the most geographically dispersed species in the group, recognized in most of the regions bordering on the Mediterranean Sea and Black Sea, Israel, Kenya, and other parts of North, Central, and South Africa, and India. The prevailing vector is the brown dog tick, Rhipicephalus sanguineus. The bacterium was isolated by Emile Brumpt in 1932 and named after A. Conor who, in collaboration with A. Bruch, provided the first description of boutonneuse fever in Tunisia in 1910.The genome of the bacterium has been sequenced and four subspecies have been identified.Rickettsia prowazekii
Rickettsia prowazekii is a species of gram-negative, alphaproteobacteria, obligate intracellular parasitic, aerobic Bacillus bacteria that is the etiologic agent of epidemic typhus, transmitted in the feces of lice. In North America, the main reservoir for R. prowazekii is the flying squirrel. R. prowazekii is often surrounded by a protein microcapsular layer and slime layer; the natural life cycle of the bacterium generally involves a vertebrate and an invertebrate host, usually an arthropod, typically the human body louse. A form of R. prowazekii that exists in the feces of arthropods remains stably infective for months. R. prowazekii also appears to be the closest free-living relative of mitochondria, based on genome sequencing.Rickettsia sibirica
Rickettsia sibirica is a species of Rickettsia. This bacterium is the etiologic agent of North Asian tick typhus, which is also known as Siberian tick typhus. The ticks that transmit it are primarily various species of Dermacentor and Haemaphysalis.Rickettsia typhi
Rickettsia typhi is a species of infectious bacterium of the genus Rickettsia; it is the causative agent of Murine typhus.The genome is similar to that of Rickettsia prowazekii.Rickettsiosis
A rickettsiosis is a disease caused by intracellular bacteria.Scrub typhus
Scrub typhus or bush typhus is a form of typhus caused by the intracellular parasite Orientia tsutsugamushi, a Gram-negative α-proteobacterium of family Rickettsiaceae first isolated and identified in 1930 in Japan.Although the disease is similar in presentation to other forms of typhus, its pathogen is no longer included in genus Rickettsia with the typhus bacteria proper, but in Orientia. The disease is thus frequently classified separately from the other typhi.Spotted fever
A spotted fever is a type of tick-borne disease which presents on the skin. They are all caused by bacteria of the genus Rickettsia. Typhus is a group of similar diseases also caused by Rickettsia bacteria, but spotted fevers and typhus are different clinical entities.
The phrase apparently originated in Spain in the 17th century and was ‘loosely applied in England to typhus or any fever involving petechial eruptions.’ During the 17th and 18th centuries, it was thought to be "cousin-germane" to and herald of the bubonic plague’, a disease which periodically afflicted the city of London and its environs during the 16th and 17th centuries, most notably during the Great Plague of 1665.Types of spotted fevers include:
Mediterranean spotted fever
Rocky Mountain spotted fever
Queensland tick typhus
Helvetica spotted feverTyphoid fever
Typhoid fever, also known simply as typhoid, is a bacterial infection due to specific type of Salmonella that causes symptoms. Symptoms may vary from mild to severe and usually begin six to thirty days after exposure. Often there is a gradual onset of a high fever over several days. This is commonly accompanied by weakness, abdominal pain, constipation, headaches, and mild vomiting. Some people develop a skin rash with rose colored spots. In severe cases people may experience confusion. Without treatment, symptoms may last weeks or months. Diarrhea is uncommon. Other people may carry the bacterium without being affected; however, they are still able to spread the disease to others. Typhoid fever is a type of enteric fever, along with paratyphoid fever.The cause is the bacterium Salmonella enterica subsp. enterica growing in the intestines and blood. Typhoid is spread by eating or drinking food or water contaminated with the feces of an infected person. Risk factors include poor sanitation and poor hygiene. Those who travel in the developing world are also at risk. Only humans can be infected. Symptoms are similar to those of many other infectious diseases. Diagnosis is by either culturing the bacteria or detecting the bacterium's DNA in the blood, stool, or bone marrow. Culturing the bacterium can be difficult. Bone marrow testing is the most accurate.A typhoid vaccine can prevent about 40% to 90% of cases during the first two years. The vaccine may have some effect for up to seven years. It is recommended for those at high risk or people traveling to areas where the disease is common. Other efforts to prevent the disease include providing clean drinking water, good sanitation, and handwashing. Until it has been confirmed that an individual's infection is cleared, the individual should not prepare food for others. The disease is treated with antibiotics such as azithromycin, fluoroquinolones or third generation cephalosporins. Resistance to these antibiotics has been developing, which has made treatment of the disease more difficult.In 2015, there were 12.5 million new cases worldwide. The disease is most common in India. Children are most commonly affected. Rates of disease decreased in the developed world in the 1940s as a result of improved sanitation and use of antibiotics to treat the disease. Each year in the United States, about 400 cases are reported and it is estimated that the disease occurs in about 6,000 people. In 2015, it resulted in about 149,000 deaths worldwide – down from 181,000 in 1990 (about 0.3% of the global total). The risk of death may be as high as 20% without treatment. With treatment, it is between 1 and 4%. Typhus is a different disease. However, the name typhoid means "resembling typhus" due to the similarity in symptoms.Typhus vaccine
Typhus vaccines are vaccines developed to protect against typhus. As of 2017 they are not commercially available.One typhus vaccine consists of formaldehyde-inactivated Rickettsia prowazekii. Two doses are injected subcutaneously four weeks apart. Booster doses are required every six to twelve months.