Common symptoms reported were scratchy throat, watery eyes and headaches.
Despite the strong smell of smoke in most parts of the city, the Environment Department (Semades) pollution monitoring network showed the air quality to be either "good" or "regular" at its nine metro-area stations. (Click here to see Semades air quality figures.)
Although Semades has not issued a smog alert, some agencies were advising residents to keep their doors and windows closed and stay indoors if possible.
The fire began Saturday morning but the prevailing winds had kept the smoke away from the metropolitan area, pushing it to the southwest toward Tala and other municipalities. The directors of more than 100 schools suspended classes Monday and Tuesday on their own accord.
In the past three days, the Jalisco Health Department has distributed 12,000 face masks in neighborhoods close to the fire.
According to health experts, smoke from wildfires contains toxic gases such as carbon monoxide that can be harmful to one's health. Smoke particles are small and can get deep into the lungs. Some are even small enough to get into the alveoli, or air sacs, of the lungs and may be absorbed into the bloodstream.
Most at risk are children, seniors, pregnant women and people who already have chronic heart or lung conditions.
The most vulnerable neighborhoods bordering the forest are Lomas de la Primavera, Venta del Astillero, La Primavera, El Colli, La Floresta del Colli, Miramar, El Briceño, Santa Ana Tepetitlan and Arenales Tapatios.
National Forestry Commission Director Juan Manuel Torres said depending on climatic conditions it could take firefighters another three days to fully bring the fire under control.
He said some 350 firefighters are working in an area of 7,500 hectares to ensure the fire does not spread out of this zone. At least 4,000 hectares of the 35,000-hectare nature reserve have been scorched by the blaze.
Torres did not rule out the possibility that given its characteristics, the fire could have been set deliberately.
In addition to the Jalisco Civil Protection and Fire Department, personnel from several municipal, state and federal agencies are contributing to the effort to fight the fire. They include the National Forestry Commission, the Secretariat of Rural Development, the National Defense Department, the federal Environment Ministry, the Red Cross, the Bosque de la Primavera Committee, the Jalisco State Police and the municipal governments of Guadalajara, Zapopan, Tala, El Arenal and Tlajomulco.
On Tuesday, Jalisco Governor Emilio Gonzalez visited "brigades" working round the clock to extinguish the blaze. He subsequently tweeted: "My recognition to the firefighters for their professional work."
He congratulated them for "working without pause."