Mexico's capital is not easily rattled: Its 20 million or so residents regularly shrug off crime, corruption, drought, gridlock, overcrowding, and bad air.
But the outbreak of swine flu, which has killed an estimated 176 people nationwide, is different. City residents are staying home in droves, and many are scared and confounded by the virus that has led authorities to close schools, offices, bars, gyms, and commercial establishments, virtually halting daily life for millions.
With clear information hard to come by, rumors are flying. Years of opaque government and corruption scandals have made many Mexicans instinctively skeptical of most official data, but today's levels of mistrust are noteworthy even for Mexico.
"There's a lack of activity, and Mexico is all about activity and people being around each other," said Alán Santoyo, who sells religious trinkets outside a cathedral in the colonial neighborhood of Coyoacan. A sign on the ancient wooden doors read: "No Mass Due To Sanitary Crisis."
Mr. Santoyo and many others hypothesize the virus was created and hyped by Mexico's government to distract the population from some bigger scandal being carried out. Others argue the official death toll is being purposely undercounted to prevent alarm from spreading, and fearful patients with mild symptoms are flooding hospitals and clinics.
In a survey this week of 410 Mexico City adults by the Mexican daily newspaper Reforma, 57 percent said they believed the government was underreporting the numbers, while 10 percent said they thought the statistics were being exaggerated. Only 19 percent believed the official figures. Another 14 percent were unsure of what to think.
Gerardo Bravo Escobar, an ear, nose, and throat surgeon who has examined patients with probable cases of swine flu in a Mexico City hospital, says his private practice has been flooded with patients exhibiting minor symptoms that can be a common occurrence in a dusty city with high levels of air pollution.
Others are disregarding Health Ministry recommendations that they wear surgical masks, stay away from congested areas and wash their hands frequently, he says.
"There's an important percentage of people who are downplaying the problem because they think [the government] is trying to cover up other problems," Dr. Bravo Escobar says.
"Other people think the opposite, and are going into a state of hysteria because they believe this thing is extremely serious and all or most of the sick patients are going to die," he adds.
Analysts say President Felipe Calderon's administration has compounded the problem by releasing only limited and sometimes confusing data about the epidemic.
For example, Health Minister José Àngel Córdova reported last Monday that there were close to 150 probable deaths from swine flu in Mexico, with 20 of the fatalities proved to be caused by the virus.
Since then, the Health Ministry has adopted stricter criteria, so the number of proven fatalities has dropped to eight, even as the number of probable deaths has risen to 176. The shift caused skepticism in the media that has apparently trickled down to the general population.
Further complicating the cloudy picture is the information trickling from state governments, which sometimes appears to conflict with federal statistics and may be judged with different criteria.
Meanwhile, health officials have also been reluctant to release demographic and geographic information on where the outbreaks are occurring.
"The information doesn't seem to be complete," says Dan Lund, whose polling firm, Mund Americas, is carrying out a study on Mexicans' perceptions of the health scare. "We don't really know the demographics of who's sick and who's dead."
In a session in Mexico's Senate Wednesday evening, opposition lawmakers blasted Mr. Cordova, accusing him of failing to keep the nation updated on the situation.
"These are overly conservative numbers and they seem to be hiding information," said left-leaning Sen. Ricardo Monreal, according to Reforma. "This is creating confusion because there's no clarity; it's opaque."
In addition to the perceived lack of information, strict measures closing schools, bars, restaurants (which are only allowed to offer takeout service), and pretty much anywhere people congregate have angered the business community.
"The economic blow is worse than the blow from [swine flu]," says Mario Sánchez Ruiz, president of a national confederation of service, trade, and tourism chambers.
He estimated the closures are causing losses of $36 million a day in the restaurant industry alone, while retailers and supermarkets are also experiencing pain.
"What's going to happen tomorrow? We can't live as a country like this, paralyzed," he says. "If this lasts four weeks, what's going to happen? No one will work for four weeks? The effect on the country would be fatal."