Monkeypox virus explained: How contagious is it virus and how to prevent it?

Monkeypox, a viral zoonotic infection is caused by the Monkeypox virus that belongs to the genus Orthopoxvirus of the Poxviridae family. It is transmitted to humans through an infected person, animal, or anything contaminated with the virus. Monkeypox to large extent is a self-limiting disease with symptoms that last anywhere between two to four weeks.

While most people infected with the virus recover on their own as the disease is usually mild, however, some severe infections in high-risk groups cannot be ruled out. According to the WHO, the case fatality ratio of Monkeypox is around three to six per cent. 

How it is transferred

Monkeypox is contagious and can be transmitted to humans in one of the following ways:

Direct contact with an infected person, animal, or material contaminated with the virus 

Close contact with the infectious rash, lesions, body fluids, respiratory droplets/secretions  

Pregnant women already infected with the virus can pass it to their fetus 

Common symptoms

Monkeypox virus causes symptoms that are similar, but less severe, to smallpox. It can cause a range of symptoms that includes fever, headache, muscle aches, back pain, low energy, and swollen lymph nodes. The disease is often accompanied by a rash on any part of the body (face, palm, feet, eyes, mouth, throat, etc) and may last for about two to three weeks. The symptoms of Monkeypox usually go away on their own, until the patient belongs to a high-risk group, which includes young children, pregnant women and individuals who are immunocompromised.  

An individual is not completely cured until all of their lesions have crusted over, the scabs have fallen off and a new layer of skin has formed.

Complications associated with Monkeypox

As mentioned earlier, Monkeypox is usually a mild infection, unless an individual has some underlying immune deficiencies. That said, some complications associated with the Monkeypox virus include secondary skin infections, bronchopneumonia, sepsis, encephalitis, and infection of the cornea.

How it is diagnosed

To diagnose Monkeypox, polymerase chain reaction (PCR) is the preferred laboratory test, especially given its accuracy and sensitivity. During the diagnosis, the tissue samples from your skin lesions — the roof or fluid from vesicles and pustules, dry crusts, etc., are sent to labs for confirmation.

The line of management

Firstly, infected individuals should strictly follow the advice of their healthcare provider. The clinical care for Monkeypox should be fully optimized so as to ease symptoms, manage complications and prevent long-term sequelae. If needed, medication for pain and fever can be used to relieve some symptoms. Besides, patients should ensure they consume fluids and a nutritious diet. Also, secondary bacterial infections should be treated as indicated. 

Vaccination against smallpox was demonstrated to be about 85 per cent effective in preventing monkeypox. Thus, a prior shot of smallpox vaccination may result in milder illness. 

However, the original (first-generation) smallpox vaccines are no longer available or recommended for the general public. But that said, a still newer vaccine based on a modified attenuated vaccinia virus (Ankara strain) was approved for the prevention of Monkeypox in 2019. The two-dose vaccine has limited availability though.

(Dr Sandeep Ghanta is Consultant Internal Medicine, Citizens Specialty Hospital, Hyderabad)