But Garrett is making a tough recovery from a potentially deadly strain of tuberculosis -- a disease she, along with many people, thought was a thing of the past.
Six months ago she was seriously ill and being treated in an isolation unit in a London hospital.
Up until recently, Garrett says she wasn't able to do anything.
"I couldn't work, wasn't able to socialize, I wasn't able to kind of live a normal life. It had a huge impact, so the idea of it being done and hopefully not coming back again is amazing," the student says.
Garrett says she felt "complete shock" at her diagnosis.
"I think there is a general sense in this country, at least for me -- which is incorrect -- that infectious diseases are completely eradicated, or that we found some way to get rid of them and that they are 'Victorian' illnesses," she says. "The reality is that's just not the case. It's definitely something people need to be aware of."
Deadlier than Iraq?
Some London neighborhoods have higher rates of tuberculosis than almost anywhere else in the world, as high as 113 per 100,000 people. That's significantly higher than in countries such as Rwanda, Iraq and Guatemala.
"We think TB is a disease of developing countries or of days gone by, but TB is a disease of today. It certainly was a disease of yesterday, and we need to make sure that it isn't a disease of tomorrow," says Dr. Onkar Sarhota, who is chair of London's Health Committee.
TB is one disease often synonymous with poverty, affecting the most vulnerable.
And it is not the only such disease worrying London's doctors.
Recent studies for Britain's National Health Service found that other diseases, widespread in the 19th and early 20th centuries, are making a comeback.
"There has been a huge rise in scarlet fever -- 14,000 [suspected] cases in the last year, the highest since the 1960s," says Dr. Nuria Martinez-Alier, a London immunologist. "We have seen a rise in the cases of tuberculosis, we've seen a rise in cases of whooping cough, we have seen more measles in the last 10 years than in the last 10 years before that," she warns.
Over the past five years in England, hospital admissions for scarlet fever have risen 136%, scurvy by 38% and cholera by 300%, though the number of scurvy and cholera cases is very small.
Modern factors like migration are contributing to the resurgence, as well as age-old afflictions: malnutrition, poverty and lack of access to health care.
In England, malnutrition has risen by 51% over the past five years, the National Health Service reports.
And there are other factors.
"We are seeing a reduced vaccine uptake, for example with measles; reduced population immunity, for example with whooping cough; increased poverty and more people on the poverty line," Martinez-Alier says.
London health officials credit awareness campaigns and free screening sessions in the city for a steady improvement in the rate of tuberculosis infection this year, though it remains high.
"It is a serious problem and we need to tackle it," says Dr. Sarhota.
Josie Garrett's recovery from TB will have taken two years when she is finished with her treatment.
She is urging awareness, so other people can get diagnosed faster than she was. "My perception of TB was something Jane Austen heroines had, not someone today."