The Australian Institute of Health and Welfare found thousands of patients took up valuable bed days for issues that could have been prevented by timely and adequate health care in the community.

Admissions include vaccine-preventable influenza, dental issues, diabetes, infections, chronic diseases and cardiovascular issues.

In Warrnambool the total number of preventable cases leapt 23 per cent from 1295 cases in 2012 to 1596 in 2017.

The highest was in 2016 when there were a staggering 1906 cases.

Of those, many were vaccine-preventable; in the last six years the number of patients who could have avoided hospital if they had been vaccinated rose each year, with 136 per cent more cases - or 116 - presenting in 2017.

That adds up to 36,322 hospital bed days.

With public hospital beds costing an average of $800 a night, that's more than $29 million of taxpayer dollars spent on cases that could have potentially been avoided.

In the Colac-Corangamite region there was a 15.7 per cent jump in preventable hospitalisations from 1112 in 2012 to 1287 in 2017, with peak numbers at 1536 in 2016.

Vaccine preventable hospitalisations shot up more than 322 per cent in five years from 22 to 93 and bed numbers totalled 20,546.

A spike of seven per cent of potentially preventable cases was recorded across Glenelg-Southern Grampians in the research period, from 1116 to 1197.

Those that could have been prevented by a vaccine skyrocketed 511 per cent from 17 cases to 104.

AIHW spokesman Richard Juckes said vaccine-preventable pneumonia and influenza, and congestive cardiac failure accounted for the most days of hospital care.

"Classifying a hospitalisation as 'potentially preventable' does not mean that the hospitalisation itself was unnecessary, however, it indicates that management at an earlier stage may have prevented the patient's condition worsening to the point of hospitalisation," he said.

"PPH rates often increase with increasing remoteness and socioeconomic disadvantage. The gap between people living in very remote areas and major cities widened between 2012 and 2017.

"Similarly, the gap between people living in the lowest and highest socioeconomic areas widened for a number of conditions.

"It's important to note that a higher rate of PPH doesn't always indicate a less effective health system, but PPH are useful for identifying variations between different groups, and understanding health inequalities."

Nationally, one in 15 hospitalisations could have been prevented through early health interventions.

People aged 65 years and over accounted for almost half (46 per cent) of all potentially preventable hospitalisations, and children (aged 0-14) made up 13 per cent (one in 8).

South West Healthcare failed to respond to The Standard's request for comment.

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