Out of a total of five confirmed cases of monkeypox in the national capital, three had a history of heterosexual contact within 21 days of onset of symptoms and two had no contact, revealed a study by the Indian Council of Medical Research (ICMR).

"Cases 2, 3 and 5 shared the history of heterosexual contact within 21 days of onset of symptoms not under influence of drug or alcohol. Cases 1 and 4 had denied any sexual contact. All the cases denied a history of same-sex contact or bisexual contact," the ICMR study said.

The ICMR report describes the five cases of human monkeypox infection detected in India without any international travel history.

The assessment of the viral kinetics in the follow-up of cases suggests the presence of the viral DNA from 5-24 POD in the lesion specimens compared to other specimens. The presence of high viral load in the lesion specimens of the cases demonstrates it as the best specimen type for the detection of MPXV DNA.

The report has further revealed that the cases did not report international travel history in the last month from the date of onset of symptoms. Case-5 had given a history of sexual contact with a male partner having similar lesions seven days before the onset of symptoms, the ICMR study said.

The confirmed monkeypox cases presented between 5-14 days post onset day (POD) of illness. Of five cases, three were male and two female with a mean age of 31.2 years and presented with mild to moderate grade intermittent fever with myalgia.

All five cases presented with mild to moderate grade intermittent fever, myalgia and lesions on the genitals, groins, lower limb, trunk and upper limb. Four cases had non-tender firm lymphadenopathy. No secondary complications or sexually transmitted infections were recorded in these cases except for HBV in one case. All the cases were mild and had a good recovery.

The clinical specimens of real-time PCR confirmed MPXV cases (n 5) from Delhi were collected sequentially every fourth-day post isolation and referred to the biosafety level-4 facility of ICMR-National Institute of Virology, Pune, for the study.

The cases were followed up (except case 5) till the lesions were healed and the scabs were fallen off. The specimens including oropharyngeal (OPS) & nasopharyngeal swab (NPS), EDTA blood, serum, urine, and lesion samples from multiple sites (lesion fluid, lesion roof, lesion base and lesion crust) were tested to assess the viral kinetics of MPXV using real-time PCR.

The study was approved by the Institutional Human Ethics Committee of ICMR-NIV, Pune, India under the project 'Providing diagnostic support for referred samples of viral hemorrhagic fever and other unknown aetiology and outbreak investigation'.