Hurricane Harvey:  Most Houston hospitals up and running, but it may take weeks for others to recover

Heavy rain has finally ended in Houston and water is beginning to recede in some areas, but healthcare facilities are still reeling from the damage caused by severe flooding from Hurricane Harvey, forcing many to close and evacuate patients.

On Thursday, the failure of the city’s water pump led Baptist Hospitals of Southeast Texas in Beaumont to cancel all services and transfer patients to other acute care facilities via ambulance and helicopter. It’s unclear when water service will be restored.

"We had no idea when we went to bed at midnight that ... we'd get the call that says the hospital would need to think about the city's water being lost," hospital spokeswoman Mary Poole told CNN. "We did not expect that and that's a game changer for us."

More than 20 hospitals, nursing homes and assisted living centers either closed or evacuated patients after the Category 4 hurricane hit the Houston area and dumped nearly 52 inches of rain. Approximately 24 hospitals are on internal disaster status, but still treating patients, Darrell Pile, CEO of the Southeast Texas Regional Advisory Council, who has been coordinating the disaster response in the region, told CNBC He predicted that 90% of the facilities would be back in service within a month.

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However, hospitals that have remained open are expecting an influx of patients once roads become passable, the Wall Street Journal reports.  The Department of Veterans Affairs hospital in downtown Houston, which has remained open all week, expects a deluge of veterans who will seek help. More than 500,000 veterans live in areas affected by the floods, according to Stars and Stripes.

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Once the immediate health needs of patients are taken care of, however, health officials expect they will have to treat patients who are exposed to waterborne and communicable respiratory and gastrointestinal diseases, notes the New York Times.  People with chronic illnesses may not be able to access their medications and many patients with kidney disease have been unable to have their dialysis because the dozens of dialysis centers were forced to shut down this week.  And then there are survivors who will suffer from post-traumatic stress syndrome and depression.