A rising number of people, mainly children and elderly, have been visiting hospitals in Dhaka over the last few weeks with common cold, cough and fever that physicians say are caused by seasonal viruses.

They also said any virus, like the adenovirus, which swept through Kolkata in India recently may be responsible for the rise in such cases.

But they were unsure which virus was dominating the infections as there is no supply of testing kits for detecting the virus.

"During March-April each year, we see a rise in the number of patients with flu-like symptoms in our country. Recent spike is the beginning indeed," Prof Dr Iffat Ara Shamsad, head of the pediatric department at Dhaka Medical College Hospital, told The Daily Star.

She added that it cannot be said which virus is dominating the infection "because most of the hospitals do not have the necessary logistics to test the virus."

The number of patients in Bangladesh Shishu Hospital and Institute (BSHI) has also increased recently, officials said.

"As season changes, viruses become active and infect people. We had seen a downward trend in viral infection in February; it has again started increasing and particularly the children are vulnerable," Prof Dr Jahangir Alam, director of the BSHI, told The Daily Star.

He opined that the recent spike in cases may not be associated with adenovirus, which has caused fatalities in Kolkata recently.

"We can suspect adenovirus infection if any patient has extreme coughing, prolonged and high fever, diarrhoea, etc," he added.

He, however, urged people, especially children and the elderly, to visit physicians if anyone shows such symptoms.

Arifa Akram, an assistant professor of virology at the National Institute of Laboratory Medicine and Referral Centre, stressed the need for maintaining health rules.

"All common viruses cause Covid-19-like symptoms. So, wearing a mask, washing hands and maintaining other health rules is crucial to stay safe," she said.

In case of prolonged symptoms, she also suggested visiting physicians.