‘Superbug’ typhoid a perfect storm
FEVER. Headache. Stomach pain. Muscle aches. Skin rashes.
Typhoid fever is a killer.
It is contracted by consuming contaminated foods or drinks.
It's believed to have been the source of many historical plagues - including one which wiped out one third of the citizens of Athens in 430BC. It also claimed a terrible toll among the first settlers of America, killing some 6000 between 1607 and 1642.
Typhoid proved particularly fatal to those who had no immune response against it - particularly young children.
But the evolution of medical science brought understanding of the disease.
First, in 1838, it was realised Typhoid was present in the excrement of the infected. This could then contaminate water sources.
Then, in 1880, the bacterium behind the disease was identified.
Finally, a vaccine was developed and introduced in 1896.
For a century Typhoid was beaten back. Sanitation measures limited its sources. Vaccination controlled its spread. Antibiotics treated the ill.
Typhoid is now rare among developed nations. Most cases are picked up through travel.
But a disturbing new outbreak has been detected in Pakistan.
RACE AGAINST TIME
Britain's Wellcome Sanger Institute reports a new 'superbug' strain of the Typoid bacteria, Salmonella Typhi, is proving resistant to a broad range of antibiotics used to treat the infection.
It's been headed that way for some time.
Three types of antibiotic were noted as not having any effect in Pakistan more than a decade ago.
Now that number is up to five.
The 'superbug' outbreak was first detected in 2016. Since then, 800 have been diagnosed with the deadly strain.
It's now been detected in Pakistan's largest city, Karachi.
Things are expected to get much worse.
Doctors are finding they have little left in their arsenal to combat its spread.
And it's still spreading.
The new Typhoid strain has been classified XDR - eXtensively Drug Resistant. This means only one category of antibiotic remains effective - the azithromycin class of broad-spectrum drugs.
The last hope to stop it escaping Pakistan is an emergency vaccination campaign.
The new drug was approved by the World Health Organisation in December.
Karachi is now attempting to distribute 250,000 jabs to children aged under five in the affected areas.
But Pakistan's population is suspicious.
Rumours are raging like wildfire among Pakistan's poorer communities.
They fear the new vaccine is the source of the outbreak.
They believe it is all part of an international conspiracy to poison their children.
So many of those exposed to the unsanitary conditions which breed the deadly bacteria are refusing vaccination.
A team of hepatitis vaccinators active in Pakistan and Afghanistan were discovered in 2011 to have been working with US intelligence agencies to track down al-Qaeda leader Osama bin Laden. This gave credence to Taliban claims that vaccination was a Western conspiracy to poison the followers of Islam.
But their scare campaign may backfire in a big way. If not controlled, the new typhoid strain could continue to mutate and become an epidemic in the region.
"Our fear is that the mutant gene will prevail - that the antibiotics we have left will be rendered useless," says Tahir Yousafzai, an infectious disease expert with Pakistan's Aga Khan University.
But how did things get so bad in the first place?
Researchers in the UK and Pakistan have been closely examining the new bacterium to find out how it evolved into what it is.
They've discovered Salmonella Typhi has exchanged DNA with another microbe, probably Escherichia coli.
"We have used genetic sequencing to uncover how this particular strain of typhoid became resistant to several key antibiotics. Sporadic cases of typhoid with these levels of antimicrobial resistance have been seen before, but this is the first time we've seen an ongoing outbreak - which is concerning," says Professor Gordon Dougan of the Wellcome Sanger Institute and University of Cambridge.
They've mapped the history of the outbreak of the 'superbug', and found the original cases to have been clustered around sewage lines.
Aga Khan University microbiology professor Sadia Shakoorand says he believes the mutation likely developed within those lines and spread into the water supply.
"The treatment options for typhoid are running out. It's time we focus on prevention, in addition to treatment," says Dr Charlie Weller of the Wellcome Sanger Institute.
He emphasises effective vaccination is the last line of defence we have.
"Vaccines offer another way to tackle drug resistant infections and we have a unique opportunity to address typhoid with a new Typhoid Conjugate Vaccine that has been recently prequalified by the World Health Organisation," he said.