MEXICO CITY  The man in the hospital bed complained of muscle aches and a fever so high he was sweating into his sheets. Two other patients, also confirmed to be infected with the swine flu virus, shared a special room with him, cut off from the general population.

“What bothers me is that they treat us as if we had done something wrong,” said the man, Néstor Vázquez, 58, peering out from behind his covers last week.

Nearly six months have passed since Mexico, with the help of laboratories in the United States and Canada, discovered the presence of a mysterious influenza virus, an unknown strain that caused a spike in the number of flu cases at a time of year when they are usually in decline. Alarmed by the highly contagious new bug, whose lethality was then uncertain, the government closed schools and other public facilities, sent soldiers into the streets to hand out masks and urged Mexicans to cover their mouths if they sneezed or coughed and to forgo handshakes and, especially, kisses on the cheek.

Mexico has had 245 deaths as of this week, helping make up the more than 4,100 deaths around the globe reported to the World Health Organization. But that is a relatively small number given the widespread contagion. For now, health experts remain most concerned with stopping the spread and watching for the possibility of the virus’s mutating into a more lethal strain.