A view of a shelter outdoors at Alto Hospicio commune after a series of aftershocks in the northern port of Iquique. REUTERS/Ivan Alvarado

Iquique - Chile says water, fuel, electricity and other essential services are being re-established three days after a magnitude-8.2 earthquake and hundreds of aftershocks that have rattled the country's far northern regions.

But pockets of poor people living in substandard housing are still suffering the brunt of the disaster.

The government also issued a three-month health alert on Friday for the quake-hit regions. It grants officials more resources to avoid the spread of infectious diseases caused by trash and contaminated water from rotting fish in port cities.