MEXICO CITY — Looking through a glass door at her eldest son sleeping between tubes of fluids and heartbeat counters, Juliana Derbez could not hold back the tears.

When the normally healthy 32-year-old had fallen sick seven days earlier, the family thought it was regular flu and gave him cough remedies from the pharmacy.

But after the government called a national alert over a potential pandemic, they rushed him to the Mexican Institute for Respiratory Diseases, where doctors believe he has the swine flu, known medically as H1N1 influenza.

Despite two days of taking antiviral drugs, Derbez's son, whose name his mother asked not be published, was still in an unstable condition Monday, barely conscious and struggling to breathe.

"This is like a nightmare happening," said the 55-year-old housewife, drying her wet eyes above a blue paper facemask that covered her mouth and nose. "I just put my trust in God that he will survive."

Derbez is one of thousands of family members praying as the numbers of people infected and dying from the swine flu in Mexico keeps shooting up.

On Monday, Health Secretary Jose Cordova said there were 149 deaths believed to be from the virus and 1,995 people who had been taken to hospital with signs of the killer bug.

Of these, 1,070 had successfully responded to treatment and been released while 776 were still fighting the flu in their hospital beds.

The numbers show a steady and alarming increase, compared to a figure of 81 deaths and about 1,000 infected just 36 hours earlier.

Cordova said that patients are responding positively to antiviral drugs, known in Mexico as oseltamivir and zanamivir, and those who died were already in an advanced state of symptoms before treatment.

But with the death toll rising so sharply, this did little to console those who had come to clinics to see their loved ones.

"We want to come here to show support and help them fight this," said Reynaldo Vertiz, waiting with his family to see his brother-in-law. "He would do the same for us."

As families waited and prayed, new sufferers were being brought into the institute.

The crowd parted and held their blue surgical facemasks, as one young man, coughing and sweating severely, was helped from a car through the hospital doors.

In response to the rising toll, Cordova extended the order to close schools from Mexico City to the entire country.

Officials are taking any action that could keep people from amassing and spreading the virus further: Roman Catholic masses have been suspended for the first time since the religious wars of the 1920s, while bars and discos have been shut down and concerts have been canceled.

But with more and more people dying, authorities say they may even have to go further and stop more services, such as the subway system.

"We have been trying to keep the economic life of the country moving as much as possible but if things develop negatively we will consider other steps," Cordova said.

Cordova said the majority of people who have died from the virus were young men and women in their prime — between 20 and 50 years old — although he said he did not why this was happening.

The so-called Spanish flu that wiped out about 50 million people after World War I also hit mostly young men and women, a medical mystery that has never been fully solved.

Some doctors have argued that the virus may actually provoke strong symptoms in those with the most powerful immune systems, leading to their deaths.

The government has recommended people hold back from giving greeting kisses and shaking hands, wear face masks outside the house and stay at home as much possible.

But on Mexico's streets on Monday, the majority of people appeared to be ignoring these guidelines and carrying on as normal — one reason why the virus might still be spreading so fast.

Schoolteacher Veronica Delgado, 45, walked along unprotected as she went to do her shopping.

"Why should I wear a mask?" she asked. "If the virus gets me, then it gets me."