The BCCI is keeping a close eye on the growing number of Covid-19 cases in India, especially in Mumbai, but remains confident that it will be able to conduct the IPL as scheduled, starting in less than a week's time. At the same time, Hyderabad has emerged as a back-up venue option, should one or more of the six designated host cities not be able to hold their matches.

The month of March has brought a rapid resurgence of Covid-19 in India, which the Maharashtra chief minister has acknowledged as a "second wave" that is "more severe than the previous one". The state of Maharashtra - of which Mumbai is a part - is on the verge of a lockdown.

"Today, I am giving an indication for a complete lockdown, but not announcing it formally," the Maharashtra chief minister Uddhav Thackeray said. "If things do not improve visibly in a couple of days and if no other solution is found, we will have to announce another lockdown like it is being done globally."

However, the BCCI has the state's assurance that the development shouldn't affect the IPL bubbles. The matches are meant to be held in a bubble without any crowds. All of the four teams who will start their IPL 2021 campaigns in Mumbai - Chennai Super Kings, Delhi Capitals, Punjab Kings and Rajasthan Royals - are staying at exclusive accommodations, and don't come in contact with anyone outside the bubble.

Franchises that ESPNcricinfo contacted said they haven't yet been spoken to about a move to Hyderabad, and remained confident that the matches would go on as scheduled. Chennai, Bangalore, Delhi, Kolkata and Ahmedabad are the other five venues.

Despite the assurances, though, there is a sense of uncertainty. It is understood that a few members of the groundstaff at Mumbai's Wankhede Stadium have tested positive for Covid-19. Everyone at the stadium is being tested every two days now - fresh tests were conducted today, the results of which are expected on Monday - but such developments could potentially test the sanctity of bubbles.

The Mumbai Cricket Association (MCA), though, is confident that the matches will not be moved out because they are being played in a bio-secure environment. A senior MCA official told ESPNcricinfo that they understand the alarm among the people, but that is also partly because the state government has been aggressive with the testing. The MCA has not received any intimation from the government that the lockdown, if it is put in place, will have any impact on the matches in Mumbai.

The staff on-site, meanwhile, is being tested every two days. Two of those who tested positive have already returned negative results. The entire staff is staying in the Garware Pavilion clubhouse, which is part of the stadium. Those who tested positive have been sent into isolation, and will return into the bubble only after testing negative.

The southern Indian state of Karnataka, and its capital city of Bengaluru, have also experienced a surge in Covid-19 cases in the past few days, and responding to the changed scenario, the Karnataka State Cricket Association has decided to "suspend" the ongoing Under-16 boys' zonal tournament.

In a statement, the association said that even though the state government's latest Covid-19 directives don't call for any restrictions in playing cricket, the tournament has been stopped temporarily "as precautionary measure". The two-day matches that are currently on would be allowed to finish, "and after tomorrow all the matches of the ongoing tournament stands suspended". The remaining matches will be rescheduled "after reviewing the Covid situation".

India recorded 89,129 new cases of Covid-19 on April 2. With 658,909 active cases, India is the fifth-worst-hit country in the world at the moment. And Maharashtra, Karnataka and Tamil Nadu, three of the six host states, are three of the five worst-hit states in India.