Why the drugs don’t work

Comment on this story


iol scitech jan 4 antibiotics

sxc.hu

In recent decades, drugmakers have slashed investment in antibiotics because of poor returns from a class of low-priced medicines that are only used for short periods, even as overuse of existing drugs has spurred the spread of resistance.

Johannesburg - Frightening cases of disease resistant to all available antibiotics have emerged in South Africa.

In August 2011, two patients were admitted to private hospitals in Joburg and became infected with a strand of Klebsiella pneuomoniae, a highly resistant bacteria.

Though test results showed their diseases could be treated with just one or two available antibiotics, both patients passed away within a few months.

But such cases represent worst-case scenarios. Not all patients infected with highly resistant bacteria pass away, according to Dr Olga Perovic, head of microbiology at the National Institute for Communicable Diseases (NICD). And horror movie scenarios aren’t playing out in hospitals across the nation, she added.

Current data on drug-resistant diseases were voluntarily reported by self-selecting hospitals and because there is no surveillance programme in place, the NICD does not have data from all South African hospitals, Perovic said.

In particular, smaller hospitals aren’t sending in suspected samples of drug-resistant diseases simply because they’re unaware of them, said Professor Guy Richards, intensive care unit head at Charlotte Maxeke Johannesburg Academic Hospital.

Overall, though, South Africa has a low prevalence rate of drug-resistant disease compared to the rest of the world, Perovic said.

From November 2011 to July 2013, the NICD confirmed 131 patients across South Africa had carbapenemase-resistant enterobacteriaceae (CRE), a particularly nasty kind of bacteria highly resistant to antibiotics. Though the actual number is likely higher, it’s a far cry from US statistics, where researchers estimate more than 2 million people are infected with drug-resistant organisms, according to a 2013 Medscape article.

Yet South Africa is far from being safe. Healthy people aren’t likely to catch drug-resistant diseases like CRE, but if a sick patient stays in a hospital with poor infection control, the patient is vulnerable to invasion by drug-resistant bacteria.

“Patients come in contact with disease in hospitals,” Perovic said.

Moreover, the number of drug-resistant diseases is rapidly rising and action is sorely needed, according to Minister of Health Aaron Motsoaledi.

To fight the growing phenomenon, South Africa will join the global movement against drug-resistant disease, which has been recorded at very high rates in every region of the world, according to a recently released World Health Organisation report.

Alongside the Department of Health, scientists, doctors and microbiologists are gearing up to attend a UN Special Assembly meeting this month, where a call for action to combat antibiotic resistance would be announced, said Dr Adrian Brink, a clinical microbiologist at Ampath, a laboratory service company.

“The whole issue of microbial resistance is quite worrying because it might mean we’ll reach a situation where doctors lose the capacity to treat diseases,” Motsoaledi said.

The department is organising a summit to draft policy on antimicrobial resistance, which will hopefully be held by the end of the year.

Brink pointed out there were different levels of drug-resistant disease – multi-drug resistant, a strain with several treatment options; extensively drug resistant, a strain with one treatment option left; and pan-drug-resistant disease, resistant to all available antibiotics.

Most worrisome of the different kinds of drug-resistant diseases are the CREs. There are many types of CRE – for example, Klebsiella pneuomoniae and E.coli – and they commonly live in the gut, where they aren’t harmful.

But once CRE bacteria travel out of the gut and into blood vessels, the patient’s life is endangered.

The last line of defence against extensively drug-resistant CRE is an expensive antibiotic called colistin, which became available in 1961.

No new, effective antibiotic classes will be available for the next 15 to 20 years to treat CRE, according to a 2012 South African Medical Journal study.

Perovic estimates that a patient infected with a drug-resistant bacteria has anywhere between a 20 percent and a 40 percent chance of dying.

 

The severe gap in surveillance data, not only in South Africa but in the rest of the world too, coupled with the rampant abuse of antibiotics and no immediate action, could lead to a post-antibiotic era, the recently released World Health Organisation report warned. - The Star

Hungry for more scitech news? Sign up for our daily newsletter


sign up
 
 

Comment Guidelines



  1. Please read our comment guidelines.
  2. Login and register, if you haven’ t already.
  3. Write your comment in the block below and click (Post As)
  4. Has a comment offended you? Hover your mouse over the comment and wait until a small triangle appears on the right-hand side. Click triangle () and select "Flag as inappropriate". Our moderators will take action if need be.

     

Join us on

IOL-Social networks IOL-Social networks IOL-Social networks IOL-Social networks