Quake shakes cold chain

1 September 2011

Diane Bos and fellow Christchurch immunisation coordinators recently addressed the National Immunisation Conference on lessons learnt from the Christchurch quake for the vaccine cold chain. FIONA CASSIE talks to Bos.

When your city is reeling in the wake of a devastating quake, your first priority is not usually your vaccination fridge. Most general practice emergency plans for maintaining the cold chain do not envisage widespread power outages and roads reduced to four-wheel drive only.

The inevitable result was that an estimated 2000 or more vaccines from practices around Christchurch had to be destroyed. And the biggest immunisation demand in immediate post-quake Christchurch was for tetanus, Hep B and Hep A for rescue and recovery workers.

Diane Bos says the city’s five immunisation coordinators and regional advisor are still working through how the lessons learnt from the Christchurch quake should influence future advice.

The biggest problem for maintaining Christchurch’s cold chain integrity was the loss of power. Bos says a large part of the city either lost power only for a very short time or not at all, which was fortunately the case for the Christchurch distribution store for vaccines. But a large number of practices in the south and east lost power for days and up to weeks. Moving vaccine stock out of the worst-hit areas was also not easy with the roads in turmoil.

The immediate challenge in the first few days for the coordinators was establishing communication with each other and then getting information out to practices. “We tried very hard to have consistent messages around immunisation, so everybody got the same message the whole way through.”

Power outages, unreliable cellphone coverage and the fact that Bos and fellow co-coordinator Ann Fraser’s usual inner city base at Pegasus Health was yellow stickered and inside the cordon, all caused problems in the early days.

“All the coordinators and the regional advisor worked from home – and we all worked in different parts of the city.” Regional advisor Linda Hill became the main coordinator – partly because her home in the north-west had power, fax, phone and email, while the others lived in harder-hit areas of the city, including one who lost her home and Bos who was without power. So Hill liaised with IMAC (the Immunisation Advisory Centre), the Ministry of Health, the vaccine manufacturers and the Christchurch distributor to ensure that one person was the hub for information flows.

Bos says in the early days, practices focused on looking after their patients and keeping their practices open – sometimes with only a cellphone and a laptop. Their first port of call for queries was the Pegasus Emergency Response Team and cold-chain issues were not high on the agenda. “What happened at the time was that vaccination was not a number one priority – which is what you would assume would happen in any kind of natural disaster,” says Bos. The quake hit at lunch-time on a Tuesday and by the weekend calls were coming in from practices wanting to know what to do with their vaccines.

Every practice is required to have an emergency plan as part of their cold-chain accreditation. But most plans were designed for short-term power outages and didn’t envisage a disaster on the scale of the Christchurch earthquakes. Practices in hard-hit areas resorted to generators for their power supply. But Bos says that caused its own problems, as the diesel generators were too unsafe to be left running at night with nobody on site, and too noisy. So they were turned off each night and turned back on each morning.

The immunisation coordinators sought advice from IMAC and vaccine manufacturers and were advised to destroy all vaccine that had been subject to fluctuations in temperature. Some practices improvised plans – one practice nurse loaded the vaccine fridge into the back of her car and took it back to her powered home. Some practices took vaccine home to the empty “beer fridge” in the garage where it could be kept separate from food. A nurse in one practice, without power for weeks, each day patiently transferred vaccine backwards and forwards between her home’s spare fridge and the practice’s generator-powered vaccine fridge.

Bos says they were lucky the quake was in summer rather than mid-winter.

“Because vaccines on the whole aren’t heat sensitive but they are freeze sensitive – if they go below zero you have to destroy every one – so it being summer probably helped.”

Work is continuing to develop new advice on emergency cold chain and immunisation plans in the wake of the Christchurch quake. “There’s still quite a bit of work to be done and we need to work with vaccine manufacturers so we get some very good guidelines.” Bos says questions being explored for future guidance include: How soon after an emergency do you resume the normal vaccination programme? Should helpful post-disaster vaccines like tetanus, Hep A and Hep B be held routinely in some or all fridges? Should there be strategically placed key storage areas for vaccines across the city? “These are just some of the ideas that need to be looked at further before we put together recommendations.”

One piece of advice is to ensure you know alternative contact details for the people you work most closely with – like their mobile and home phone number and home email address. “Also to quickly determine who will be your key contact person. But the key message when anything (major) happens is to be guided by your immunisation coordinators,” says Bos. “As I don’t think there’s one standard message, as the problems may be different next time.”

While individual practices can respond to localised problems, there needs to be a collective response when faced with a disaster that prompts a national state of emergency.