B virus

B virus, also known as Herpes B, is a virus that infects macaque monkeys. It is part of a group of viruses called Simplexviruses and is similar to the virus that causes cold sores in humans. Unlike cold sores, B virus affects the nervous system and is not found in the blood.

When macaque monkeys carry this virus, it usually causes symptoms like mild cold sores. However, when humans accidentally get infected, it can become very serious. Researchers working with rhesus macaques have sometimes gotten infected by accident.

In humans, B virus can cause a severe brain infection called encephalitis. Without early treatment, this infection can be very harmful. That is why quick diagnosis and proper care are very important if someone gets infected with B virus.

History

B virus was first found in 1932 after a young doctor, William Brebner, was bitten by a rhesus monkey during polio research. Though his bite healed, he later became very sick and passed away. Doctors found a tiny germ in his body.

Soon after, a scientist named Albert Sabin studied these samples and named the virus B virus. He showed that this virus could make people very sick.

Since then, a few more people have gotten sick from the virus while working with monkeys.

Virology

Structure

B virus is about 200 nanometers wide and looks very similar to two other viruses called HSV1 and HSV2. It has a special shape made from many tiny parts called an icosahedral capsid. This capsid is made from 150 hexons and 12 pentons. Around the capsid is a loose layer called the envelope, which has proteins that help the virus attach to host cells. Between the capsid and the envelope is another layer called the tegument.

Genome

The full genetic code, or genome, of B virus was discovered in 2003 from a sample taken from a rhesus macaque. Like other herpes viruses, B virus has double-stranded DNA that is about 157 kilobase pairs long. The proteins on the surface of B virus are about 50% similar to those on HSV viruses, especially HSV-2. B virus lacks a specific gene found in HSV viruses, which means it uses different ways to grow inside nerve cells.

Infection

B virus can infect people, but this is very rare. It usually happens if a person is bitten or scratched by an infected macaque monkey, or touches the monkey's eyes, nose, or mouth. It is possible but uncommon for an infected person to pass the virus to another person. Visiting areas where these monkeys live, especially places like temples, can increase the risk. Even in places where the virus is found, cases in humans are still rare.

When humans get infected with B virus, they can become very sick. Without treatment, the illness can become worse. This virus is special because it is the only virus from non-human primates known to cause serious illness in people.

Prevention

When working with macaque monkeys that may carry the virus, it is important to use protective gear. This helps prevent infection from bites, scratches, or contact with fluids near the eyes or other sensitive areas. Cleaning these areas right away if they happen is also very important to stay safe.

Treatment

Getting help quickly is important if someone might have the B virus. Doctors need samples from the person and, if possible, from a monkey to test for the virus.

One medicine, called Acyclovir, has helped stop the disease from getting worse in some cases. Treating the infection right away can help prevent serious problems.