That situation will likely get worse with 42% of the country's gastroenterology specialists expected to retire in the next 10 years, the NZ Society of Gastroenterology (NZSG) warns.
''Increases in the prevalence of bowel cancer, inflammatory bowel disease and Hepatitis C, together with the demands of the rollout of the National Bowel Screening Programme, are placing huge pressure on the capacity of GE specialists to deliver high quality, timely services to patients,'' the society's workforce analysis report said.
''Substantial numbers of patients nationwide are already enduring unacceptably long waiting times for gastroenterology follow-ups.
''There are simply not enough GE specialists and not enough graduates coming through to meet current needs.''
New Zealand has 93 gastroenterology specialists, a per-capita ratio of 1.93 per 100,000.
The Southern region's ratio is 1.88 - four district health board regions have no specialists at all.
Australia has three specialists per 100,000 people.
New Zealand has started training nurses as endoscopists, but numbers were too small to have an immediate effect.
''Given the need for experience, it will be years before the potential of this initiative will be realised.''
Gastroenterology treats a range of conditions which are highly prevalent: New Zealand has one of the highest rates of bowel cancer in the world, a high and fastest-growing rate of inflammatory bowel disease, and at least 50,000 New Zealanders have Hepatitis C.
Report co-author Thomas Caspritz said the NZSG recommended DHBs be directed to establish new gastroenterology positions, and that the country as whole should try to match the Australian model of three doctors per 100,000 people.
More work needed to be done on recruitment and retention, he said.
''We rely on overseas-trained doctors to fill open positions and about 40% of the current GE workforce gained their specialist qualifications overseas,'' Dr Caspritz said.
''The training output in New Zealand is eight GE specialists a year, and around half of them leave New Zealand to take up positions overseas.''
The NZSG is holding its annual conference in Dunedin this week.
