Explained: What is monkeypox?

In a world grappling with Covid, the emergence of a rare contagion has scientists worried -- monkeypox.

Although there are no infections in India yet, cases have been reported from Britain, Italy, Portugal, Spain, Sweden and the United States.

And Canada, Australia as well as France are investigating potential infections of the disease that can have a fatality rate of 10 per cent. In total, more than 100 suspected and confirmed cases have been reported.

WHAT IS MONKEYPOX?

Monkeypox is a rare viral infection similar to human smallpox. It was first discovered in 1958 in monkeys kept for research. The first human case of monkeypox was recorded in 1970. The disease occurs primarily in tropical rainforest areas of Central and West Africa and is occasionally exported to other regions.

“Monkeypox is a rare zoonotic disease that is caused by infection with monkeypox virus. Monkeypox virus belongs to the family Poxviridae, which also includes the viruses causing smallpox and cowpox disease,” said Dr Monalisa Sahu, consultant, Infectious Diseases, in Hyderabad's Yashoda Hospitals.

“Cases of monkeypox have been reported outside Africa, in US, Europe, Singapore, UK, and these cases have been linked to international travel and import of monkeys harbouring the disease,” Sahu told PTI.

SYMPTOMS

According to the World Health Organization (WHO), monkeypox typically presents itself with fever, rash and swollen lymph nodes and may lead to a range of medical complications. The disease is usually self-limiting with the symptoms lasting from two to four weeks. Severe cases can occur. In recent times, the case fatality ratio has been around 3-6 per cent but can be up to 10 per cent. There are no reported deaths in this current spread.

TRANSMISSION

Monkeypox is transmitted to humans through close contact with an infected person or animal, or with material contaminated with the virus. It's thought to be spread by rodents such as rats, mice and squirrels, WHO said.

The disease is transmitted through lesions, body fluids, respiratory droplets and contaminated materials such as bedding. The virus is less contagious than smallpox and causes less severe illness, it said.

Health officials have noted some of these infections may be transmitted through sexual contact. The WHO said it was also investigating many cases being of people identifying as gay or bisexual.

“The natural reservoir of monkeypox remains unknown, although African rodents and non-human primates (like monkeys) can harbour the virus and infect people, causing the disease,” said Sahu.

INCUBATION

The incubation period or interval from infection to onset of symptoms of monkeypox is usually from six to 13 days but can range from five to 21 days, according to WHO.

“In Africa, monkeypox has been shown to cause death in as many as one in 10 persons who contract the disease,” Sahu said.

TREATMENT

Vaccines used during the smallpox eradication programme also provided protection against monkeypox. Newer vaccines have been developed of which one has been approved for prevention of the disease. An antiviral agent developed for the treatment of smallpox has also been licensed for the treatment of monkeypox, according to the global health body.

Vetarinarian Gaurav Sharma said studies are needed to better understand the risk.

"While close physical contact is a well-known risk factor for transmission, it is unclear at this time if monkeypox can be transmitted specifically through sexual transmission routes," Sharma, from the Centre for Animal Disease Research And Diagnosis (CADRAD), in Bareilly, Uttar Pradesh, told PTI.

"Considering the increased case fatality rates, and probable aerosol route of transmission, there is certain risk for India too," he said.

Sharma noted that studies are currently underway to further understand the epidemiology, sources of infection and transmission patterns.