By Gleb Bryanski and Gleb Stolyarov

MOSCOW, Nov 13 (Reuters) - Several African and ex-Soviet countries have expressed interest in buying Russia's vaccine against smallpox and mpox viruses, as well as testing systems and antiviral treatments, Russia's consumer and health watchdog told Reuters.

The vaccine, called Orthopoxvac, was developed by the Vektor laboratory in Siberia and registered by Russia's health ministry in 2022 following clinical trials, which, according to Vektor, showed that the vaccine is safe and effective.

The trial results have not been published.

"The countries of the Eurasian Economic Union, the Commonwealth of Independent States, as well as the African countries most affected by the mpox outbreak, have expressed interest in acquiring Russian treatments," the watchdog told Reuters.

It did not say which countries expressed interest.

Mpox is a viral infection that spreads through close contact, causing flu-like symptoms and pus-filled lesions. Most cases are mild, but the disease can also be fatal.

In August, the World Health Organization (WHO) declared a global public health emergency after an mpox outbreak in Democratic Republic of Congo (DRC) that had spread to neighbouring countries and beyond.

The DRC and Rwandan governments did not respond to requests for comment about the Russian vaccine.

Spokespeople for the health ministries in Burundi and Uganda and a senior public health executive in Nigeria said they had no knowledge of efforts to buy Russian mpox vaccines.

A senior public health executive in Uzbekistan said the government did not need the vaccine because there had been no mpox cases in the country.

The governments of Kazakhstan, Tajikistan, Kyrgyzstan and Georgia did not immediately respond.

Some countries, including the United States and France, have pledged to donate doses of the two main vaccines against the virus made by Bavarian Nordic BAVA.CO and KM Biologics to combat the outbreak.

Scientific papers published by Vektor researchers show the laboratory has worked on the vaccine since at least 2015. However, it has not yet published trial results, and the shot has not been approved by regulators outside Russia.

Vektor, which reports to the consumer and health watchdog, did not respond to a request for comment.

The watchdog did not say how much of the vaccine Russia has in stock. Russia has had two cases of mpox so far, according to data from the U.S. Centers for Disease Control and Prevention.

(Reporting by Gleb Bryanski and Gleb Stolyarov; Additional reporting by Clement Manirabarusha in Bujumbura, Burundi, Elias Biryabarema in Kampala, Uganda, MacDonald Dzirutwe in Lagos and Ange Kasongo in Kinshasa, Muhammadsharif Mamatkulov in Tashkent and Maria Gordeeva in Almaty;Editing by Josephine Mason and Ros Russell)

((gleb.bryanski@thomsonreuters.com;))