Deadliest Viruses on Earth

Coronavirus-COVID-19

 

SARS-CoV-2 comes from the big family of viruses as SARS-CoV, referred to as coronaviruses, and was first identified in December 2019 in the Chinese city of Wuhan. The infection most likely comes from bats, like SARS-CoV, and passed through an intermediate animal prior to contaminating people.

Considering its appearance, the virus has actually infected tens of thousands of individuals in China and thousands of others worldwide. The ongoing break out caused an extensive quarantine of Wuhan and nearby cities, restrictions on travel to and from affected countries, and an around the world effort to develop diagnostics, treatments, and vaccines.

The illness caused by SARS-CoV-2, called COVID-19, has an estimated death rate of about 2.3% (current studies show 3-4%). People who are older or have underlying health conditions appear to be most at risk of having severe disease or complications. Typical signs include fever, dry cough, and shortness of breath, and the disease can progress to pneumonia in serious cases.

Ebola Virus

The very first known Ebola outbreaks in humans struck at the same time in the Republic of Sudan and the Democratic Republic of Congo in 1976. Ebola is spread out through contact with blood or other body fluids, or tissue from contaminated individuals or animals.

The known strains vary considerably in their deadliness, Elke Muhlberger, an Ebola infection specialist and associate teacher of microbiology at Boston University, informed Live Science. One strain, Ebola Reston, does not even make individuals sick. But for the Bundibugyo strain, the fatality rate depends on 50%, and it depends on 71% for the Sudan strain, according to WHO.

The outbreak underway in West Africa started in early 2014, and is the largest and most complex outbreak of the disease to date, according to WHO.

 

HIV

In the modern-day world, the deadliest virus of all may be HIV. “It is still the one that is the biggest killer,” said Dr. Amesh Adalja, an infectious doctor, and representative for the Infectious Disease Society of America. An approximated 32 million individuals have died from HIV since the disease was first recognized in the early 1980s.
The HELP was reported by some doctors in the early 1980s in young males having one or more complex symptoms such as extreme pneumonia, an uncommon vascular cancer, sudden weight reduction, inflamed lymph nodes, and basic loss of immune functions. All these young patients were homosexuals.

Not long after the disease was discovered in non-homosexual patients who were provided blood (blood transfusion) or blood products. In 1984 the agent causing the disease was identified by research teams from the Pasteur Institute in France and the National Institute of health in the U.S.A. In 1986 the virus was named human immunodeficiency infection (HIV). The significant cell infected by HIV is the helper T-lymphocyte, which is a significant component of the immune system.

As the HIV infection continues in the host, the reduction of helper T-lymphocytes leads to failure of the immune system and the infected individual becomes vulnerable to other diseases. Cells in the main nerve system can also be infected by HIV. Current studies on HIV reveal that the infection contaminates and multiplies in monkeys however does not cause disease in them, which suggests that HIV is host-specific.

HIV is transmitted by sexual contact, contact with blood, and breastfeeding. Healthcare employees can also get HIV during expert activities. Preventing direct contact with HIV is a very important procedure for preventing the disease. Avoidance of’ intravenous drugs with common syringes and use of sterilized needles/syringes and utensils is important. Now vaccine against HIV has been manufactured and its speculative administration in people began in early 2001 in South Africa.

Hantavirus

Hantavirus pulmonary syndrome (HPS) first gained wide attention in the U.S. in 1993, when a healthy, young Navajo guy and his fiancée living in the Four Corners area of the United States died within days of establishing shortness of breath.

A couple of months later on, health authorities separated hantavirus from a deer mouse living in the house of one of the infected people. More than 600 individuals in the U.S. have now contracted HPS, and 36% have passed away from the disease, according to the Centers for Disease Control and Prevention. The virus is not transmitted from a single person to another, rather, individuals contract the disease from exposure to the droppings of infected mice.

Previously, a different hantavirus caused a break out in the early 1950s, during the Korean War, according to a 2010 paper in the journal Clinical Microbiology Reviews. More than 3,000 troops ended up being infected, and about 12% of them died.
While the virus was new to a Western medication when it was found in the U.S., researchers realized later that Navajo medical customs explain a comparable health problem, and connected the illness to mice.

 

Hepatitis

Hepatitis is an inflammation of the liver. It is normally caused by a viral infection, toxic agents, or drugs. It is characterized by jaundice, abdominal pain, liver enlargement, fatigue, and sometimes fever. It might be moderate or can be severe and can cause liver cancer.

The different kinds of viral liver disease are Hepatitis A (formerly called infectious hepatitis is transmitted by contact with feces from infected people.) Hepatitis B (serum hepatitis). Hepatitis C (previously called non-A, non-B Hepatitis) passes through blood, from mother to child during pregnancy and later and by sexual contact. Hepatitis D (Delta Hepatitis), Hepatitis E (a virus transferred through the faeces of an infected individual), Hepatitis F, G (caused by viruses yet unidentified). Viruses of Hepatitis A, B, and C are much better known.

Hepatitis A Virus (HAV) is an RNA virus (non-enveloped), which causes moderate short-term, less virulent disease. Hepatitis C virus (HCV) is also an RNA virus (enveloped) that causes infusion hepatitis, which is less serious than Hepatitis A or hepatitis B, but Hepatitis C often results in persistent liver disease. The recent work of Halbur and coworkers (2001) reveals that pigs could be the source of the virus of hepatitis E.

Hepatitis B (HBV) is the 2nd significant kind of hepatitis. It is triggered by a DNA virus which is very common in Asia, China, Philippines, Africa, and the Middle East. Hepatitis B is transmitted by the exchange of body fluids, for example, blood serum, breast milk, and saliva, from mother to kid during birth or afterward and by sexual contact. During intense attacks of Hepatitis B tiredness, loss of appetite, and jaundice are reported. Infected persons can recuperate entirely and become unsusceptible to the infection.

People with chronic liver disease infection are at the risk of liver damage. Hepatitis can be managed by embracing hygienic procedures, with regular vaccination and screening of the blood/ organ/ tissue of the donor.
WHO estimates that, in 2015, infections with hepatitis B and C virus– the two out of 5 hepatitis viruses responsible for the greatest burden of illness– caused 1.34 million deaths worldwide.

Dengue

Dengue infection first appeared in the 1950s in the Philippines and Thailand and has since spread throughout the tropical and subtropical areas of the world. Approximately 40% of the world’s population now lives in areas where dengue is endemic, and the disease– with the mosquitoes that bring it– is most likely to spread further as the world warms. Dengue sickens 50 to 100 million individuals a year, according to WHO.

Although the death rate for dengue fever is lower than some other viruses, at 2.5%, the infection can cause an Ebola-like disease called dengue hemorrhagic fever, which condition has a mortality rate of 20% if left without treatment. “We need to think more about dengue infection because it is a genuine risk to us,” Muhlberger said.

A vaccine for Dengue was authorized in 2019 by the U.S. Food and Drug Administration for usage in kids 9-16 years old living in areas where dengue prevails and with a validated history of virus infection, according to the CDC. In some nations, an approved vaccine is readily available for those 9-45 years of age, but again, recipients need to have contracted a confirmed case of dengue in the past. Those who have not captured the virus in the past could be at risk of developing extreme dengue if provided the vaccine.

MCQs with Answers: The Deadliest Viruses on Earth

 

Frequently Asked Questions (FAQs): The Deadliest Viruses on Earth