1.Marburg virus

Marburg virus is a hemorrhagic fever virus of the Filoviridae family of viruses and a member of the species Marburg marburgvirus, genus Marburgvirus. Marburg virus (MARV) causes Marburg virus disease in humans and nonhuman primates, a form of viral hemorrhagic fever. The virus is considered to be extremely dangerous. The WHO rates it as a Risk Group 4 Pathogen (requiring biosafety level 4-equivalent containment). In the United States, the NIH/National Institute of Allergy and Infectious Diseases ranks it as a Category A Priority Pathogen and the Centers for Disease Control and Prevention lists it as a Category A Bioterrorism Agent. It is also listed as a biological agent for export control by the Australia Group.

In 2009, expanded clinical trials of an Ebola and Marburg vaccine began in Kampala, Uganda.

2.Ebola virus

Ebola virus EBOV, formerly designated Zaire ebola virus) is one of five known viruses within the genus Ebola virus. Four of the five known ebola viruses, including EBOV, cause a severe and often fatal hemorrhagic fever in humans and other mammals, known asEbola virus disease (EVD). Ebola virus has caused the majority of human deaths from EVD, and is the cause of the 2013–2015 Ebola virus epidemic in West Africa, which has resulted in at least 28,638 suspected cases and 11,315 confirmed deaths.

Ebola virus and its genus were both originally named for Zaire (now the Democratic Republic of Congo), the country where it was first described, and was at first suspected to be a new "strain" of the closely related Marburg virus. The virus was renamed "Ebola virus" in 2010 to avoid confusion. Ebola virus is the single member of the species Zaire ebolavirus, which is the type species for the genus Ebolavirus, family Filoviridae, order Mononegavirales. The natural reservoir of Ebola virus is believed to be bats, particularly fruit bats, and it is primarily transmitted between humans and from animals to humans through body fluids.

The EBOV genome is a single-stranded RNA approximately 19,000 nucleotides long. It encodes seven structural proteins: nucleoprotein(NP), polymerase cofactor (VP35), (VP40), GP, transcription activator (VP30), VP24, and RNA-dependent RNA polymerase (L).

Because of its high mortality rate (up to 83-90%),EBOV is also listed as a select agent, World Health Organization Risk Group 4 Pathogen (requiring Biosafety Level 4-equivalent containment), a U.S. National Institutes of Health/National Institute of Allergy and Infectious Diseases Category A Priority Pathogen, U.S. CDC Centers for Disease Control and Prevention Category A Bioterrorism Agent, and listed as a Biological Agent for Export Control by the Australia Group.

3.Hantavirus

Hantaviruses are single-stranded, enveloped, negative sense RNA viruses in the Bunyaviridae family.

They normally infect rodents and do not cause disease in these hosts. Humans may become infected with hantaviruses through contact with rodent urine, saliva, or feces. Some strains of hantaviruses cause potentially fatal diseases in humans, such ashantavirus hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS)—also known as hantavirus cardiopulmonary syndrome (HCPS)— while others have not been associated with known human disease. HPS (HCPS) is a "rare respiratory illness associated with the inhalation of aerosolized rodent excreta (urine and feces) contaminated by hantavirus particles."

Human infections of hantaviruses have almost entirely been linked to human contact with rodent excrement, but recent human-to-human transmission has been reported with the Andes virus in South America.

Hantavirus is named for the Hantan River area in South Korea where an early outbreak was observed. The virus was isolated in the late 1970s by Karl M. Johnson and Ho-Wang Lee.

4.Influenza A virus subtype H5N1

Influenza A virus subtype H5N1, also known as A(H5N1) or simply H5N1, is a subtype of the influenza A virus which can cause illness in humans and many other animal species. A bird-adapted strain of H5N1, called HPAI A(H5N1) for highly pathogenic avian influenza virus of type A of subtype H5N1, is the highly pathogenic causative agent of H5N1 flu, commonly known as avian influenza ("bird flu"). It is enzootic (maintained in the population) in many bird populations, especially in Southeast Asia. One strain of HPAI A(H5N1) is spreading globally after first appearing in Asia. It isepizootic (an epidemic in nonhumans) and panzootic (affecting animals of many species, especially over a wide area), killing tens of millions of birds and spurring the culling of hundreds of millions of others to stem its spread. Many references to "bird flu" and H5N1 in the popular media refer to this strain.

According to the World Health Organization and United Nations Food and Agriculture Organization, H5N1 pathogenicity is gradually continuing to rise in endemic areas, but the avian influenza disease situation in farmed birds is being held in check by vaccination, and so far there is "no evidence of sustained human-to-human transmission" of the virus. Eleven outbreaks of H5N1 were reported worldwide in June 2008 in five countries (China, Egypt, Indonesia, Pakistan and Vietnam) compared to 65 outbreaks in June 2006 and 55 in June 2007. The global HPAI situation significantly improved in the first half of 2008, but the FAO reports that imperfect disease surveillance systems mean that occurrence of the virus remains underestimated and underreported. In July 2013 the WHO announced a total of 630 confirmed human cases which resulted in the deaths of 375 people since 2003.

Several H5N1 vaccines have been developed and approved, and stockpiled by a number of countries, including the United States (in its National Stockpile), Britain, France, Canada, and Australia, for use in an emergency.

Research has shown that a highly contagious strain of H5N1, one that might allow airborne transmission between mammals, can be reached in only a few mutations, raising concerns about a pandemic and bioterrorism.

5.Lassa virus

Lassa virus (LASV) is an arenavirus that causes Lassa hemorrhagic fever, a type of viral hemorrhagic fever (VHF), in human and non-human primates. Lassa virus is an emerging virus and a select agent, requiring Biosafety Level 4-equivalent containment. It is endemic in West African countries, especially Sierra Leone, the Republic of Guinea, Nigeria, and Liberia, where the annual incidence of infection is between 300,000 and 500,000 cases, resulting in 5,000 deaths per year.

Recent discoveries within the Mano River region of west Africa have expanded the endemic zone between the two known Lassa endemic regions, indicating that LASV is more widely distributed throughout the tropical wooded savannah ecozone in west Africa. Currently, there are no approved vaccines against Lassa fever for use in humans.

6.Junin virus

The Junin virus or Junín virus is an arenavirus that causes Argentine hemorrhagic fever (AHF). The virus takes its name from the city of junín, around which the first cases of infection were reported, in 1958.

The Junin virus is associated with Argentine hemorrhagic fever. People infected with the virus suffer from tissue inflammation, sepsis and skin bleeding. The problem is that the symptoms can appear to be so common that the disease is rarely detected or identified in the first instance.

7.Crimean–Congo fever virus

The Crimea-Congo fever virus is transmitted by ticks. It is similar to the Ebola and Marburg viruses in the way it progresses. During the first days of infection, sufferers present with pin-sized bleedings in the face, mouth and the pharynx.

8.machupo virus

The Machupo virus is associated with Bolivian hemorrhagic fever, also known as black typhus. The infection causes high fever, accompanied by heavy bleedings. It progresses similar to the Junin virus. The virus can be transmitted from human to human, and rodents often the carry it.

9.Kyasanur forest virus

Scientists discovered the Kyasanur Forest Virus (KFD) virus in woodlands on the southwestern coast of India in 1955. It is transmitted by ticks, but scientists say it is difficult to determine any carriers. It is assumed that rats, birds and boars could be hosts. People infected with the virus suffer from high fever, strong headaches and muscle pain which can cause bleedings.

10.Dengue virus

The dengue virus (DENV) is the cause of dengue fever. It is a mosquito-borne single positive-stranded RNA virus of the familyFlaviviridae; genus Flavivirus. Five serotypes of the virus have been found, all of which can cause the full spectrum of disease. Nevertheless, scientists are finding their understanding of dengue virus may be simplistic, as rather than distinct antigenic groups in space and time there appears to be a continuum. This same study identified 47 strains of dengue virus. Additionally, coinfection with and lack of rapid tests for zika virus and chikungunya complicate matters in real world infections.

Its genome is about 11000 bases that codes for three structural proteins (capsid protein C, membrane protein M, envelope protein E) and seven nonstructural proteins (NS1, NS2a, NS2b, NS3, NS4a, NS4b, NS5). It also includes short non-coding regions on both the 5' and 3' ends. Further classification of each serotype into genotypes often relates to the region where particular strains are commonly found or were first found