A study published in the British Medical Journal (BMJ) said that symptoms of the monkeypox virus that is observed in the current outbreak have significant differences from those reported during previous outbreaks in African regions.

The study did a retrospective observational analysis of 197 people - all men - who tested positive for the disease in London. 196 of the 197 participants identified themselves as gay, bisexual or other men who have sex with men.

According to the study, rectal pain and penile swelling (edema) are commonly seen in the current outbreak as compared to the previous outbreaks in the Democratic Republic of Congo in 2007-11 and Nigeria in 2017-18.

Researchers have recommended that clinicians test patients presenting with these symptoms for the monkeypox virus. Further, patients who tested positive for monkeypox and are exhibiting symptoms of extensive penile lesions or severe rectal pain "should be considered for ongoing review or inpatient management".

The study revealed that there is a possibility that transmission of the virus could happen from individuals who are either asymptomatic or had few symptoms as only a fraction of the participants (26.5%) had known contact with someone with a confirmed monkeypox infection.