Evidence of medical records left lying around, vaccines not kept at the right temperature, and dangerously dirty rooms with maggots found at one practice, have all been uncovered during inspections of GP surgeries, an official report reveals on Thursday.

The inspections of 1,000 surgeries across England since April by the Care Quality Commission found "some examples of very poor care", with "very serious failings" found at nine surgeries. Some of the problems were so serious that patients' safety was endangered, with some potentially at risk of dying.

While many people received an excellent service, more than a third of surgeries (34%) failed to meet at least one of the required standards on good practice and protecting patients.

In some surgeries inspectors found that Adrenalin and other emergency drugs, for use if a patient suffered a potentially fatal anaphylactic shock, were out of date. "Because of that the drugs might not have worked. For me that's very serious. Someone in anaphylactic shock could have died," said Professor Steve Field, the NHS chief inspector of family doctor services.

Field and his team found management of medicines to be inadequate in 45 (23.3%) of the 193 surgeries where the procedures were inspected.

The CQC cited the example of the Norris Road surgery in Sale, Cheshire, which it said did not have adequate medicines management policies and procedures. "We found a number of medicines used to treat patients in emergency situations were past their expiry date and also found some vaccines stored in the fridge that were six months out of date," the CQC's inspection report said.

The findings have been published following an unprecedented number of inspections as part of a crackdown on standards of all NHS and social care. Overall, though, Field said, "many people receive good quality care from their GP".

From April the CQC will introduce more inquisitive and robust inspections of surgeries, which will include a CQC inspector, a GP, trainee GP and practice nurse or practice manager. Inspectors will visit all of the NHS's 211 clinical commissioning groups once every six months, inspecting a quarter of the practices in that area. In addition, from next October all GP surgeries in England will start being given an Ofsted-style rating for the first time.

Dr Maureen Baker, chair of the Royal College of GPs, said many of the 1,000 surgeries had already been identified as a concern and that major failings were isolated incidents. "Patients should expect high quality and consistent care from their GP practice, and the vast majority of practices do an excellent job of delivering quality care while maintaining the highest possible standards," she said.

At the Wolds practice in Horncastle, Lincolnshire, some patients' drug records were found to be "incomplete", [and] "there were shortfalls in the security of medicines at the practice" and, in addition, "there had been a series of dispensing errors [at the surgery's pharmacy] where some patients had received medicines incorrectly." Among other findings, Field also warned about the potential dangers of GPs or practice nurses injecting patients with out of date, and potentially ineffective, vaccines, with children at particular risk. In such a situation a woman who thought she had been correctly vaccinated against German measles as a girl could, when pregnant, give birth to a deaf and blind baby because she did not in fact have immunity against measles.

Patients not correctly immunised could later become "very, very poorly and then die", said Field. "That could affect many hundreds of patients in single surgeries. If they've not tracked it for years, that's a major problem. You're talking about problems which can damage this generation and the next generation", he added.

Hygiene and infection control were problematic in 76 (21.9%) of the 347 surgeries where the issue was examined. At the Dale Surgery in Sneinton, Nottinghamshire, inspectors found maggots, dead insects and dust and cobwebs. Inspectors had "serious concerns with the standards of cleanliness and infection control at the surgery, which included an infestation of pests".

The surgery, which was otherwise rated as good, took immediate action to improve hygiene, although no system for regular monitoring was put in place.

One in three practices did not keep patients' electronic records up to date, which could mean that a patient may not be called for a blood test at the right time.At the Norris Road surgery, run by Dr Michael Florin, "we found confidential records left unattended or not securely storied in a number of areas of the practice". One in 12 (8.2%) surgeries has too few GPs, nurses or people to act as chaperones when female patients are undergoing certain types of examination. At Dr Syed's practice in Rochdale, Lancashire, "there were not enough qualified, skilled and experienced staff to safeguard people's health, safety and welfare." In some places staff had not undergone a criminal records bureau check.

Almost one-in-eight (11.7%) surgeries offer patients no set way to complain. At another 12% of surgeries, staff did not know how to deal with safeguarding children or vulnerable adults – for example who to refer concerns to if a girl said she was being abused by a family member. At the King Street surgery in Burton-on-Trent, Staffordshire, staff's lack of training on that "meant that patients were not protected from the risk of abuse because the provider had not taken reasonable steps to identify the possibility of abuse and prevent it from happening."

Inspectors judged almost one-in-four (24.1%) GPs' premises to be either unsafe or unsuitable, for example because they had access that made entry hard for people with mobility problems, such as stairs but no ramp.

Difficulty getting appointments is a common problem, Field added. At the Kingshurst medical practice in Birmingham, for example, patients queued outside and even brought chairs to sit on in their quest to see a GP, with one patient having to wait 90 minutes to be seen.

Jeremy Hunt, the health secretary, said tougher inspections "will root out poor standards and celebrate the best".

But Jamie Reed, the shadow health minister said: "Nobody expects this poor level of care when visiting their family doctor. Patients at these surgeries are being badly let down."

Katherine Murphy, chief executive of the Patients Association, said: "GP services make up the vast majority of public interactions with the health and social care system, so it is vital that access is fair to all, and that practices are carefully monitored to ensure that they are providing a high quality service for patients living in that community. Out-of-hours care must operate effectively, efficiently, safely and compassionately in the best interests of the patients."