Not one bug but two: lessons learnt from recent gastro outbreaks

It was a tough winter around the country for many hospitals this year. A bad flu season, tight budgets and bulging wards.

So with the flu season all but over and spring blossoming around the country, many nurses were looking forward to the workload pressure easing.

Then in came a report of vomiting and diarrhoea.

It is every infection prevention and control (IPC) nurse specialist’s bogeyman. Has there been a breach of infection control practice – possibly due to staff being stressed and tired after a long winter? Will the case be a one-off? Or are the infection control practices of the hospital or residential aged care facility about to be tested by an explosive norovirus outbreak?

On 14 September Whangarei Hospital had one vomiting patient. By the next morning it had 10 more and promptly closed its surgical ward. A few days later, further down the island, Whakatane Hospital closed the door on its Acute Care Unit because of a diarrhoea outbreak hitting patients and staff. Then just a few days after that, Whakatane’s big sister hospital, Tauranga, had infection control staff running between the fourth and second floor battling to contain three small outbreaks in three different wards.

No gastro outbreak was the same. Vomiting was widespread and violent in Whangarei’s Ward One outbreak, while down the island in Whakatane diarrhoea dominated and Tauranga faced a mixture of both.

A norovirus outbreak isn’t easy to deal with “whichever end it comes from”, as one nurse put it, but with violent vomiting comes the added risk of the airborne spread of a virus so virulent that ingestion of just one viral particle can cause infection.

All three hospitals quickly contained and controlled the outbreaks using their established outbreak plans (see case studies for details). Other hospitals around the country empathised and hoped they wouldn’t need to put their own plans to the test this spring.

Nursing Review spoke to the infection prevention and control nurse specialists involved in the latest outbreaks about their experiences, and asked what advice they had to share with their colleagues around the country.

“Extremely virulent”

Whangarei’s orthopaedic ward was full and the hospital busy when a single vomiting case overnight turned into a major suspected norovirus outbreak.

The rapid acceleration of cases meant airborne spread was possibly involved, as the first affected room – located in the middle of the ward – was open to the ward corridor.

Mo White, IPC clinical nurse specialist for Northland DHB, says it turned to the DHB’s microbiologist to help interpret the literature indicating norovirus particles are only airborne for ‘a short time’ following vomiting.

“Now you can’t measure ‘a short time’,” says White, “but the literature goes on to say that these viral particles, which are extremely virulent, will land on surfaces, curtains and just everywhere, so people can be infected via [the airborne virus settling on] the surfaces they touch.”

The decision was made by the Outbreak Management team to close the ward; elective surgery was put on hold; and the number of cleaners was doubled and their hours were extended to keep the infection at bay through thorough environmental cleaning and careful infection control practices.

White says the team had little option but to close the ward with isolation rooms already full, which is an increasing trend with the number of patients coming into hospitals with multi-drug-resistant organisms (MDRO).

A security staff member distributed information pamphlets, sanitising gel and personal protective equipment (PPE) outside the ward’s closed doors; extra linen and PPE were ordered to get the ward through the weekend; and the team met regularly, with updates being sent out to staff and local media.

White says the DHB’s microbiologist was proud that staff managed to contain the outbreak to one ward, but it had been very demanding on staff caring for 13 symptomatic patients who were in traction or recovering from hip or knee surgery. “To have to access the toilet in a hurry is a real challenge.”

A debrief is scheduled for October, and White says some of the outbreak challenges the IPC team want to discuss include how to manage isolation in a shared room that can’t be isolated from the rest of the ward, and how to ensure an affected outbreak ward has enough appropriately qualified staff.

Not one bug, but two

Two separate bugs were circulating at the time of the gastro outbreaks at Tauranga and Whakatane Hospitals – and sometimes both bugs were present not only in the same ward but also in the same patient.

“It always pays to think that not just one organism is necessarily causing the symptoms,” says Bay of Plenty DHB IPC nurse specialist Adrienne Stewart. “There may be at least a couple of things circulating at the same time.”

She says this means it needs to be stressed to staff that they need a new set of PPE (i.e. disposable gloves and gown) for each patient they are looking after. “So [this means] not going from one symptomatic patient to another in a four-bed room with the same set of gloves and gown on, which we sometimes see.”

Whakatane Hospital IPC nurse specialist Sarah Winship adds, in retrospect, that the DHB’s press release should have talked about a gastro outbreak closing Whakatane’s unit, rather than a suspected norovirus outbreak, as in the end only two of the five symptomatic patients actually had norovirus.

Test results from the 20 symptomatic cases in Whakatane and Tauranga found seven in Tauranga had norovirus alone and one had C. difficile; and two of five patients in Whakatane had norovirus, with one of those having both norovirus and
C. difficile. The cause of seven of the cases is unknown, as stool specimens were either not collected for testing or tests came back negative for both organisms.

“One of the unfortunate things is that sometimes staff are a bit tardy in getting specimens sent off,” says Adrienne Stewart. She says it is important for staff to be prompt in not only reporting patients with gastroenteritis symptoms but also in sending specimens for testing.

“Another thing I found difficult at times was that although we’ve placed symptomatic patients into isolation promptly, very often I would go past and find both doors to the isolation unit wide open.”

This meant that any well-placed card on the outside of the doors – setting out and stipulating isolation procedures – was unable to be seen by anybody walking in and out of the room. “I’d ask for the doors to be closed so the door card could be seen but five minutes later the doors would be open again.”

Stewart says the outbreaks are “hugely disruptive” for staff, particularly at the beginning when moving orthopaedic patients and beds into an isolation area, and then cleaning and disinfecting behind them, so one part of the ward can continue to function normally. “But in my experience here, it is far better you do that,” she says, “than have symptomatic patients spread throughout a surgical ward and have to have the whole ward closed down (and surgery cancelled).”

The disruption of a spring gastro outbreak in the wake of a tough winter and ‘flu season is what every hospital and facility plans and hopes to avoid. But with an estimated 50,000-plus norovirus cases alone occurring in New Zealand each year, it is inevitable that outbreak plans will be tested someday. The hope is that the plan will do its job – as in these occasions – and the outbreak is contained and lessons learnt for the (unfortunately) inevitable next time it is tested. Meanwhile, as Mo White says, remember: hand hygiene, hand hygiene, hand hygiene.

ADVICE TO SHARE

Hand hygiene, hand hygiene, hand hygiene!

• During gastro outbreaks, wash your hands with soap and water, not just sanitising gel, as there is mixed evidence about the effectiveness of alcohol hand disinfectant against norovirus.
• Use an N95 mask if the patient is vomiting and do NOT touch the mask. Instead, remove gloves, wash your hands and remove the mask by grasping tapes or elastic and drawing it away from your face. Wash your hands again after disposing of the mask.
• Isolate a suspected gastroenteritis patient quickly to contain the risk of infection.
• Send specimens from symptomatic patients as soon as possible for testing.
• Do NOT assume that all symptomatic patients are infected by the same organism, or that a gastro outbreak is norovirus.
• Keep your ear to the ground about gastroenteritis in the community so that staff can be forewarned to be extra vigilant for cases of vomiting and diarrhoea.
• Emphasise the need for good environmental hygiene using bleach, as gastroenteritis bugs – both norovirus and C. difficile – can survive on contaminated surfaces for a long time.
• Maintain frequent communication with the outbreak team about the number of cases; an outbreak log sheet can be useful to document and trace the outbreak pattern.

Norovirus is a highly contagious virus that can cause the sudden onset of gastroenteritis with acute nausea (81 per cent), vomiting (54 per cent), abdominal cramps (72 per cent) and diarrhoea (85 per cent). The virus is shed in faeces and can spread very easily from faeces to mouth through contaminated hands, food, water and items in the environment. There is also some documented evidence of airborne spread through aerosolised vomit. The virus is very hardy and can survive for a long time on handrails, taps and door knobs. The incubation of norovirus can be between 10 and 50 hours and there can be asymptomatic infections.

Clostridium difficile (C. difficile) is a bacterium spore shed in faeces that is the most common cause of diarrhoea in hospitalised patients. Spores can live for long periods on surfaces and faeces-contaminated surfaces such as toilets and commodes can be a ‘reservoir’ for C. difficile. Up to 20 per cent of hospitalised patients are estimated to be colonised with C. difficile, but only a minority experience symptomatic disease.
Source: Guidelines for the Management of Norovirus Outbreaks in Hospitals and Elderly Care Institutions (2009). Ministry of Health.

Measures for the Prevention and Control of Clostridium difficile Infection (2013). Ministry of Health.

CASE STUDY: Whangarei Hospital

• First suspected case was reported in a four-bed room of the 32-bed orthopaedic ward on the afternoon of Thursday 14 September, with vomiting the major symptom.
• The affected room and some other similar four-bed rooms open directly onto the ward corridor (i.e. no doors).
• The vomiting and diarrhoea were unexpected gastroenteritis symptoms so the affected patient was isolated, airborne precautions put in place and other room occupants closely monitored for symptoms.
• The clinical head of service and duty manager was informed.
• By the following morning (Friday 15 September), the ward had 11 patients meeting the case definition for norovirus – most vomiting – and two more patients became symptomatic later in the outbreak.
• The ward was full, including isolation rooms, and the hospital very busy so was unable to isolate all affected patients and contacts from the other patients in the ward.
• The Outbreak Management team met at 10am on Friday 15 September and the decision was made to close the ward and inform the media.
• Seven staff from the outbreak ward were off-duty with varying symptoms during the outbreak (not all with norovirus).
• Seven of the 13 symptomatic patients had samples tested for norovirus and two were positive for norovirus.
• The outbreak was contained and officially over within 10 days.

CASE STUDY: Tauranga Hospital

• On Thursday 21 September, alerted to four gastroenteritis cases in the 40-bed orthopaedic ward – the largest ward in the hospital located on the fourth floor. In all there were to be five orthopaedic ward cases.
• Two days later (23 September), and two floors below, the first of four more symptomatic cases appeared in one of the three medical wards that occupy the second floor.
• Then on 24 September another 22-bed medical ward on the second floor had four symptomatic patients.
• These patients were moved into isolation in a section of the ward that, where it was possible, was divided by double doors so the rest of the ward could continue to function as close to ‘business as usual’. The contact patients were also shifted into a separate area of the isolation section so they could be kept under surveillance.
• Of those involved in the initial orthopaedic ward outbreak, one patient was found to have norovirus, one had Clostridium difficile
  (C. difficile), and three others did not have specimens sent for testing.
• Test results from the 23 September medical ward outbreak found all four symptomatic patients had norovirus and one also had C. difficile.
• Of the patients in the second medical ward outbreak on 24 September, two were found to have norovirus and two had no specimens taken.
• The confirmed norovirus patient in the orthopaedic ward had been seen by health professionals working on both floors. Anecdotally, several staff were off work with gastroenteritis-like symptoms during these outbreaks as well.

CASE STUDY: Whakatane Hospital

• On Saturday 16 September, a patient at Whakatane Hospital’s Acute Care Unit came down with gastroenteritis symptoms – no vomiting but abdominal pain and diarrhoea.
• By the end of the weekend, five patients were ill and four staff (two more staff were sick by Tuesday).
• The Acute Care Unit is made up of 16 individual bays that are open (no doors) to the corridor of the horseshoe-shaped unit.
• Because of the location of the affected patients – in one end of the horseshoe (used primarily for acute admissions requiring ventilation/high dependency care) – and the number of staff off sick, the decision was made on Monday 18 September to close the unit to new patients and restrict access by visitors and staff.
• The unit was split into an affected half and non-affected half and staff were allocated to work on either side of the demarcation zone (there were empty bed spaces between the two areas as the unit was not full).
• Test results from the five patients showed that one had norovirus, one had both norovirus and C. difficile, one had just C. difficile and the other two were tested for norovirus and C. difficile but came back negative for both.