What Is The Most Deadly Virus On Earth?

In this world, there is a silent war that has been going on for billions of years. Trillions of killings are taking place every day, and we don't even know it. The protagonist of this bloody battle is the most deadly virus on earth, the Marburg virus.

Pathogenic structure

Marburg virus is the first filovirus to be discovered. The viral genome is single-stranded negative-stranded RNA, which is transmitted from animals to humans, but the source of the virus is still unknown.

Way for spreading

Virus-infected non-human primates and patients are the main source of infection. The virus is usually transmitted to humans by infected non-human primates, and then from sick to other healthy people. As the most deadly virus on earth, it is extremely contagious. The more severe the symptoms are, the more contagious the patient is, and the less contagious is the incubation period. Humans are not part of the virus' natural cycle and are only infected by accident.

It is mainly transmitted through close contact, that is, contact with dead animals and dead bodies, as well as blood, secretions, excrement, vomit, droplets, etc. of infected animals and patients, through mucous membranes and damaged skin. In African epidemic areas, outbreaks of this disease have occurred many times due to exposure to patient corpses during funerals. Nosocomial and laboratory infections can also be caused by close contact. In addition, iatrogenic transmission can occur through the use of contaminated syringes, etc. It has been reported that within 3 months of clinical recovery, Marburg virus can still be detected in semen, so there is the possibility of sexual transmission. Infection of experimental animals by aerosols containing this virus has also been reported.

Pathogenesis

After entering the human body, Marburg virus first invades dendritic cells and macrophages, and then is carried to regional lymph nodes, spreads in the lymphatic system, and infects the liver, spleen and other tissues through the blood. The pathogenesis of the most deadly virus on earth consists of the following two aspects:

1. Virus infection of host cells leads to direct cell damage: the mechanism is: the virus binds to the lectin on the cell surface, leading to cell necrosis through the toxicity of viral proteins.

2. The interaction between viruses and the immune system leads to indirect damage to cells: the mechanism is:①The virus spreads from the invasion site to various systems, thereby inhibiting the body's innate immune response, including dendritic cells and macrophages.②Due to viral infection, the activation of dendritic cells to T cells is partially inhibited, thereby affecting the humoral immune response;③A large number of lymphocyte apoptosis is produced throughout the infection process, resulting in immunosuppression;④Infected macrophages Cells produce various mediators and lead to severe lesions through various pathways, such as tissue factor expression on the cell surface to trigger disseminated intravascular coagulation; release of cytokines and chemokines leads to vascular dysfunction, hypotension, and multiple organ failure Wait.

Clinical manifestations

After Marburg virus infection, it can cause a disease with fever and bleeding symptoms as the main clinical manifestations, which is called Marburg hemorrhagic fever. Marburg hemorrhagic fever is also known as green monkey disease and African hemorrhagic fever because Marburg virus originates from African green monkeys and is mainly prevalent in Africa. The early symptoms of Marburg hemorrhagic fever are similar to other infectious diseases such as malaria and typhoid, so diagnosis is sometimes difficult, especially when it occurs sporadically.

The incubation period of Marburg hemorrhagic fever is generally 3 to 9 days. The patient has sudden fever, chills, headache, general fatigue, profuse sweating, muscle aches, sore throat, cough, and chest pain. The initial symptoms are very flu-like, followed by nausea, vomiting, diarrhea, abdominal pain, rash all over the body, and finally nose and mouth bleeding, blood in urine, vaginal bleeding, and gastrointestinal bleeding. In severe cases, shock may occur, and about 1/4 of the patients die.

The onset is characterized by sudden onset of fever, headache, and muscle pain. Within a week, a red rash appeared on the skin, followed by vomiting, chest and abdominal pain, and diarrhea. Afterwards, the patient may develop yellow gallbladder, confusion, liver failure, and severe bleeding. The recovery process of patients is very long, and sequelae such as scrotal contraction, recurrent hepatitis, spondylitis, infection of eyes and subauricular glands, etc. often occur. Medical equipment and support in different regions have a great impact on the survival rate. In some developed countries, the mortality rate is only 25%, but in developing countries the mortality rate can be as high as 100%. So it is considered to be the the most deadly virus on earth.

Treatment measures

General supportive care

Should be in bed rest, in-situ isolation treatment. Give high-calorie, moderate vitamin liquid food or semi-liquid food. Sufficient fluids and electrolytes should be supplemented, and the rehydration should be mainly isotonic fluid and saline, commonly used are balanced saline and glucose saline. to maintain water, electrolyte and acid-base balance.

Symptomatic and complication treatment

Those with obvious bleeding should be transfused with fresh blood to provide a large number of platelets and coagulation factors with normal function; those with significantly decreased platelet counts should be transfused with platelets; those with disseminated intravascular coagulation can be treated with anticoagulant drugs such as heparin. Cardiac insufficiency should be treated with cardiotonic drugs; renal oliguria should be treated as acute renal failure: limit fluid intake, apply diuretics, maintain electrolyte and acid-base balance, and take dialysis therapy if necessary; patients with impaired liver function Hepatoprotective treatment can be given. In critically ill patients, antibiotics can be used as appropriate to prevent infection.

In short, countries should actively take measures to deal with the most deadly virus on earth before it happens.