Large-scale global demand for a smallpox vaccination that has been demonstrated to protect against monkeypox has prompted health authorities to issue a warning against replicating the unequal distribution witnessed during the Covid pandemic.

Since May, there have been outbreaks of monkeypox all over the world, despite the disease long being endemic in some regions of West and Central Africa.

It has led to a rush on doses of the only monkeypox vaccine authorized worldwide, which is made by the Danish pharmaceutical company Bavarian Nordic.

Here is the current situation about the vaccine's availability and efficacy.

About 85% of the population is protected.

The vaccine, known as MVA-BN and sold as Jynneos in the US and Imvanex in Europe, was initially created to combat smallpox.

The orthopoxvirus family includes both of these viruses.

According to Olivier Schwartz, chief of the virus and immunity division at the Pasteur Institute in France, the monkeypox and smallpox virus proteins are 90–95 percent identical.

So it is a tried and true method to stop it with a vaccine that is very similar, he added.

Bavarian Nordic's vaccination against monkeypox appears to be highly successful, despite the lack of extensive evidence on its effectiveness.

According to Schwartz, "the vaccination protection figure of 85% stems from field investigations in the DR Congo in the 1980s and 1990s and is quite inaccurate."

The vaccination can still be successful, he continued, even if a patient has already contracted monkeypox, according to research conducted in 2018 on medical professionals and experiments on macaques.

Additionally, some immunity to monkeypox exists in those who had a dose of the smallpox vaccination before to 1980, though it is unclear how long this immunity will last.

According to tests conducted in the 2000s, about 30% of those who had received the vaccine two decades previously still possessed smallpox antibodies, according to Schwartz.

A booster dose, according to him, would "reactivate cellular immunity, even after 20 to 40 years," he continued.

However, immunity "decreases over time and the persistence of neutralizing antibodies against monkeypox has never been tested," cautioned Yannick Simonin, a virologist at the University of Montpellier.

350,000 dosages to a country that is unnamed

In 2003, Bavarian Nordic teamed up with US health officials and has since shipped 30 million pills to the nation.

The business has declared it will send seven million more tablets to the United States since monkeypox began spreading outside of Africa in May.

According to the World Health Organization, there are approximately 16 million doses of the vaccine available globally, most of which are in bulk form and will require months before they are ready for use.

It has been challenging to ascertain the precise number of stocks owned by nations, which on occasion have refrained from disclosing figures, upsetting some non-governmental organizations and politicians.

Bavarian Nordic, which has the capacity to generate up to 30 million doses annually, has similarly been coy about disclosing the destination of its shipment.

The business revealed on Wednesday that it would send 350,000 pills to a "undisclosed" nation in the Asia-Pacific area.

The usefulness of two more smallpox vaccines, ACAM2000 and LC16, against monkeypox is now being researched.

ACAM2000 has more than 100 million doses now on hand in the United States, however it is thought to have more adverse effects than more recent vaccines.

ACAM2000 manufacturer Emergent BioSolutions told AFP that it can presently generate more than 18 million doses annually and could increase that to 40 million if necessary.

We seek equity.

Despite having a lengthy history of fighting monkeypox, Africa has not yet received any vaccinations.

This year, there have been more than 3,000 confirmed cases of monkeypox in Africa, and 70 reported deaths, according to medical professionals.

In order to prevent a repeat of the disparity in access to Covid vaccines between wealthy and developing countries, the WHO has urged those countries who do have vaccines to share them.

35 nations have asked for access to the monkeypox vaccine, according to Meg Doherty, head of the WHO's global HIV, hepatitis, and sexually transmitted illness programs, who made the announcement on Sunday.

She warned attendees at a Montreal conference during the International AIDS Conference that there was "quite a possible risk" that wealthy nations were asking for the doses.

She continued, "We demand equity.