It IS 30 degrees outside, easily 40-plus inside my personal protective equipment (PPE), yet I feel a chill run through me as I approach Aminata's bed (patient details altered to protect identity).

She's the first patient I've seen tonight and she doesn't seem to be breathing. She is six years old.

I move as quickly as I dare to her bedside, trying not to catch my suit on anything that might tear it but anxious to check on her. Relief. She gives a little hiccup and then winces in pain. She hasn't passed away but she is very ill. Her hands are cold, her pulse rapid, her features sunken. She is badly dehydrated but no-one has been able to establish an IV line.

I sit her up and encourage her to take a drink. She regards me with wide brown eyes, equal parts afraid and curious about the apparition in a space suit who brings water. Eventually she takes a sip, then a gulp, then downs the bottle. I hold her hand until she settles but she isn't my only patient. My buddy and I work along the ward changing a soiled sheet here, hanging IV fluids there, giving out morphine or a kind word as we pass.

I hate to turn my back on the ward but my goggles are fogging and I have the beginning of a dehydration headache - time for us to go to decontamination and begin the meticulous drill of removing the PPE safely. I'll rest for an hour then return. Maybe I haven't done all I wanted but if I eased one person's suffering a little then it's been a good day.

Scenes like this are typical in the ebola treatment unit (ETU) where I'm one of many NHS volunteers. It's a far cry from my usual work environment as a nurse in a ­Glasgow intensive care unit. Normally I'm surrounded by advanced life support kit, specialist drugs and ­monitoring equipment. Here, care is basic and supportive. There is no proven specific treatment for ebola so the cornerstone is hydration and ­symptomatic relief - buying patients' immune systems time to clear the virus.

Each day is a cycle of hand-washing and temperature checks. We cut out any personal contact such as handshakes or hugs. I sleep under a mosquito net, religiously take my antimalarials and slather on insect repellent as malaria and other ­tropical illnesses often manifest with symptoms similar to ebola. Even headaches are investigated. Everyone checks their buddy's health when donning PPE, just to be sure.

So why do this? When I see disasters I always think "someone should do something". Volunteering was my chance to contribute rather than just cheer on someone else.

I've never been prouder as an NHS employee than when I saw how many of my colleagues had volunteered, and that pride hasn't waned. Collectively, we are making a difference.

And we aren't the only ­healthcare workers in the ETUs. I work alongside Cuban volunteers and a growing contingent of Sierra Leonian national nurses and community health officers.

If anyone deserves to be called heroes, it is the national staff.

The UN ranks Sierra Leone the 177th poorest country out of 186, with correspondingly poor ­healthcare and infrastructure. Since the early days of this outbreak, Sierra Leonian medics have responded bravely and at great personal risk due to the initial lack of PPE.

National staff are the backbone of any ETU. They were here in the beginning and will stay long after we've departed. Clinical work remains an important part of my role but what really makes the difference is training and mentoring the nationals. Building capacity is the best legacy we can leave.

I do hope more NHS staff follow us. There has been great progress here, made possible by £230 million in aid from the UK, but much work remains to be done.

I know that some are critical of the investment being made here during a time of austerity, perhaps unconvinced by purely humanitarian arguments. But it is in our interests to stop ebola now, at source. History has rarely rewarded complacency; the cost of tackling ebola today will be nothing compared to the cost if it is left unchecked.

Soon it will be out of my hands as I return home in a week. I will receive a health screening and be expected to follow robust guidelines which limit my travelling, require I stay in touch with public health, abstain from patient care for 21 days and avoid crowded areas from which I can't exit quickly if I become unwell.

Though I'm sure cabin fever will set in after 21 days, when I think back to last week when Aminata was declared ebola negative and walked out of the ETU and into the arms of her family, I'll know that I did a good day's work.