Monkeypox DNA found in semen, researchers say

Fragments of monkeypox virus were detected in semen in a series of patients in Italy, raising questions about whether sexual transmission of the disease is a possibility, scientists said on Monday.

The current understanding is that the disease-causing virus is spread through close contact with an infected person, who can pass the virus through characteristic skin lesions or through large droplets spread through the respiratory system. Many of the monkeypox cases in the current outbreak are among sexual partners who have had such contact.

However, cases of sexually transmitted diseases such as HIV/AIDS, chlamydia and syphilis are known to be caused by pathogens that pass from one person to another specifically through semen, vaginal secretions and other bodily fluids.

Researchers at the Spallanzani Institute, a hospital and infectious disease research center in Rome, were the first to highlight evidence of monkeypox virus in the semen of four patients in Italy in a report on June 2.

Since then, six out of seven of the patients at the institute have had genetic material from the virus found in their semen. In one, a sample tested in the laboratory of one of the patients suggests that the virus found in his semen was capable of infecting another person and replicating.

These data, which are being presented for publication, do not represent sufficient evidence to prove that the biological characteristics of the virus have changed to the point that its mode of transmission has evolved, Francesco Vaia, director general of the institute, told Reuters.

“However… Having an infectious virus in the semen is a factor that tipped the balance strongly towards the hypothesis that sexual transmission may be one of the ways in which the virus is transmitted,” he said.