In early March, 40-year-old Ravi Dosi, a chest specialist in India, saw a baffling surge in patients with respiratory problems at outpatient clinics.
"There was almost a 50% jump in patients with upper respiratory issues and sore throat. They were not responding to antibiotics. Testing was still low and we didn't really know what was going on," Dr Dosi, who works at Sri Aurobindo Institute of Medical Sciences, a 1,156-bed private medical college in the central city of Indore, told me.
Less than a fortnight later, Dr Dosi began seeing an uptick in admissions of Covid-19 patients. Around the end of March, the hospital was receiving 28 infected patients every day.
They had dry cough, fever, and difficulty breathing. Their blood oxygen levels were low. They were reporting loss of taste and smell.
In the first wave of patients, nearly a dozen came from far-flung districts, more than 150km (93 miles) from Indore, a bustling commercial city in Madhya Pradesh state. The state has now become a hotspot, with nearly 400 confirmed infections out of the more than 6,400 infections and nearly 200 deaths across the country so far.
By the second week of April, Dr Dosi and his team of 100 doctors and nearly an equal number of nursing staff working 24/7 in three shifts, were treating 144 Covid-19 patients. (Thirty-one had been treated and sent home already.)
A total of 38 patients were in intensive care. Twenty-one of them were critical. There had been seven deaths. "We are handling the largest number of Covid-19 patients in India," Vinod Bhandari, a surgeon and chairman of the hospital, told me.
Doctors now believe that the infection was spreading in the community long before the government admitted to it, and testing slowly ramped up. Until two weeks ago, Indian health authorities had been denying community transmission.
Now a new study by Indian Council of Medical Research (ICMR) using surveillance data from 41 labs in the country has hinted at community transmission: 52 districts in 20 states and union territories reported Covid-19 patients. Some 40% of the cases did not report any history of international travel or contact with a known case. (The survey was based on swabs collected from nearly 6,000 patients between 15 February and 19 March. Of them 104 tested positive for Covid-19)
Back in the hospital in Indore, the doctors are battling the surge in infections.
Three isolation wards spread over two floors floors are stacked with patients. (The hospital has earmarked 525 beds for Covid-19 patients.) Isolation wards have younger patients with mild infection, while elderly patients with more severe symptoms are in intensive care. The oldest patient is a 95-year-old man, and the youngest is a four-month-old boy.
The team of doctors handling patients includes chest specialists, anaesthetists, microbiologists, and dermatologists. There are patients with a lot of underlying medical conditions - diabetes, hypertension, even cancer - so all the specialists have been called in to help with the treatment.
Dr Dosi wakes up early, puts on protective gear - scrubs, face masks and shields, N95 masks, gowns, double gloves and shoe covers - before going on his rounds of the patients. Doctors say they are not facing a shortage of gear yet.
They are using 22 ventilators to help the critical patients breathe, and also providing oxygen supplies to others using nasal cannulas (nose prongs).
In the isolation wards, patients are given oral medication - antibiotics and hydroxychloroquine (commonly known as HCQ), an anti-malarial drug - and directed to maintain social distancing and wash their hands regularly.
"I have never seen a challenge and crisis like this in my career. I have heard stories about an outbreak of plague in Surat [in 1994]. But this seems to be much bigger. The biggest challenge is to keep hopes alive and be positive," says Dr Dosi.
Keeping hopes up for patients in isolation can be taxing. Three tests, say doctors, are being done for the infection - if the first test comes out positive, the patient remains in isolation for two weeks, and is tested twice on two days after the quarantine period. If the last two tests come back negative, the patient is discharged. If not, the patient has to stay in isolation for another two weeks. "It is a tough grind, mentally," says one doctor.
For the last three weeks, Dr Dosi has been living in the hospital, away from his wife, two sons and parents. His father is a retired pathologist. They communicate via hurried video calls, between his frantic trips to the isolation wards and intensive care.
I ask him when does he expect this to "get over", so that he can go home.
"In a couple of weeks," he says. "The lockdown should have helped to slow down the infection."
Dr Dosi is alluding to the strict 21-day lockdown India imposed on 24 March to halt the spread of the infection.
Things are getting better, he says.
"I am getting 10 patients for admission in isolation wards, and two patients severe enough for intensive care every day now. Earlier this week, it was 50:50."
It is possibly too early to hazard a guess about when admissions will slow down to single digits. As more people are tested, the number of patients can easily rise again.
It's been unrelenting, Dr Dosi says.
Early, on Friday, I sent him a text to find out what was going on.
"Please. Have an emergency in ICU," he replied.