Monkeypox: is it the new pandemic?;

Both confirmed and suspected cases of monkeypox are increasing internationally. Many of these are of unknown origin, which means that the virus that causes it is probably spreading under the radar of health authorities.

Scientists are beginning to express concerns about the possibility of a new epidemic, as cases have been detected in at least seven countries and the number is growing every day. What follows, in the form of a Q&A, based mainly on New Scientist, is a summary of what we know so far:

* What is this disease?;

It is a relatively rare disease caused by a virus (Poxvirus) that belongs to the same family as the smallpox virus. The disease usually spreads among monkeys in Central and West Africa, where it is endemic, but periodically jumps to humans, having caused small outbreaks to date. It was first identified in laboratory monkeys in 1958. The first case of human infection was recorded in the Republic of Congo in 1970.

* How many cases have there been during the current outbreak?;

There have been 35 confirmed cases and 72 suspected cases worldwide, according to the database created by Morris Kremer of Oxford University and John Brownstein of Harvard Medical School. Confirmed cases have been found in the UK, Portugal, Spain, Sweden, Belgium, the US and Canada. Scientists believe that this is probably only the “tip of the iceberg” and that there are many more undiagnosed cases.

* Are all the cases connected?;

This is not clear. Cases have been found that are linked to another known case, and others with no (at least known) association. The UK Health Security Agency (UKHSA) now estimates that the virus is spreading from person to person in countries with confirmed cases. Several involve male homosexuals and bisexuals, so health authorities are urging people of this sexual orientation to watch out for any rashes or other suspicious symptoms so that they can seek medical attention in good time.

* How does the disease spread?;

According to the World Health Organization (WHO), it can be transmitted by inhaling infected particles and by contact with skin rashes of the disease or with materials contaminated by the virus. According to the US Centers for Disease Control and Prevention (CDC), human-to-human transmission is believed to occur primarily through large respiratory particles that do not travel far, so there must be prolonged close face-to-face contact to become infected.

The virus is not thought to spread easily between people and, according to the UKHSA, the risk of infection in the population ‘remains low’. The disease can also be spread through contact with an infected person's clothing, towels, sheets or other items. It is not considered a sexually transmitted disease, but it can be more easily transmitted during sexual contact through the skin.

It is also possible to be transmitted from an infected animal to a human, if one is bitten by it or touches its blood, bodily fluids, rashes etc., or if one eats poorly cooked meat from such an animal.

* What are the symptoms?;

They include fever, headache, muscle aches, back pain, swollen lymph nodes, colds and exhaustion. Rashes may also appear, first on the face and then on other parts of the body, including the genitals. The rash initially resembles that of chickenpox.

* How deadly is it?;

The disease is usually mild and most patients recover in a few weeks without treatment. In Africa it can kill up to 10% of people infected, but this is, according to the WHO, for one of the two strains, that of the Congo, which is the most dangerous, while the other strain, the West African strain, kills one in 100 patients. So far, genetic analysis has identified in Britain only the second West African strain, but there is no equivalent sequencing data from other countries.

The above death rates are the proportion of confirmed cases, but given that there are probably several more mild cases that go undetected, the actual mortality of the disease is estimated to be significantly lower. According to the WHO, children are more at risk than adults of becoming seriously ill. Also, infection of a pregnant woman can lead to pregnancy complications and even stillbirth.

* Are there any treatments or vaccines?;

Yes. The antiviral drug tecovirimat (Tpoxx) has been approved in the US and Europe against this disease and dalmatitis in animals. The drug significantly reduces the likelihood of death. There is also the vaccine Jynneos (also known as Imvanex and Imvamune), also approved in the US and Europe, which prevents infection in adults. In addition, those who are old enough to have been vaccinated as children against smallpox still have some protection.

* Have there been outbreaks outside Africa in the past?;

Several such outbreaks had occurred, but usually each time they involved only a few outbreaks and with a very limited geographical spread.

* So the current spike is the biggest ever?;

No. There have been larger ones in Africa, such as in 2001 and 2002, when 485 cases and 25 deaths were recorded in the Republic of Congo. In 2017 and 2018, 122 confirmed or probable cases and seven deaths had been reported in Nigeria.

* Could the current outbreak be caused by a new strain of the virus?;

It remains unknown. However, the fact that so many cases have been detected in different countries suggests that this is a more contagious strain than others in the past. Although it is possible that simply random events, such as the presence of super-carriers, may have helped an older strain of the virus to spread more widely. It is too early to draw a definitive conclusion. Genetic analysis of more samples from outbreaks will reveal whether it is a different strain.

* Is a new pandemic likely to emerge?;

Scientists estimate that the new outbreak can be controlled by tracing contacts and vaccinating those considered to be at risk of infection. Although they do not completely rule out a pandemic, they do not consider it likely and do not think it is on the same level as coronavirus.