Antibiotic Awareness Week: seven infections that are getting harder to treat

This week is the first ever global Antibiotic Awareness Week, which aims to increase understanding of how bacteria are evolving to beat our best drugs and what we can do about it. The Wellcome Trust recently commissioned research which showed that the problem of drug resistant infections has not been well communicated.

Clare Ryan, a senior media officer at Wellcome, takes a closer look at seven common bacteria which are becoming harder to treat with the antibiotics doctors have available.

Based on photomicrographic data, this illustration depicts the ultrastructural morphology exhibited by a single Gram-positive Clostridium difficile bacillus.

Credit: CDC/ James Archer

Based on photomicrographic data, this illustration depicts the ultrastructural morphology exhibited by a single Gram-positive Clostridium difficile bacillus.

Mycobacterium tuberculosis (TB)

A lot of people still associate TB with industrial revolution era Britain, but the disease has been on the rise in the UK over the past 10 years. TB ought to be treatable by prescribing a course of drugs including the once potent antibiotics isoniazid and rifampicin, but bacteria have developed resistance to these medicines. This has led to the emergence of multi-drug-resistant TB and the even less treatable extensively drug-resistant TB (XDR-TB) of which there are still thankfully few cases in the UK.

Neisseria gonorrhoeae (gonorrhoea)

People are often reluctant to talk about this sexually transmitted infection, but recent outbreaks of the infection in the north of England have raised its profile. Although gonorrhoea was once treatable with penicillin and other antibiotics, the bacterium that cause this disease have developed such high levels of resistance that there is only one drug left that can treat it. Worryingly, even this last antibiotic, called ceftriaxone, is becoming less effective.

Klebsiella pneumoniae

Perhaps less well-known than some of the others on this list, Klebsiella pneumoniae was recently highlighted in a WHO report into global antibiotic resistance as being increasingly common in hospitals. The bacteria can cause a wide range of conditions including pneumonia, urinary tract infections, septicaemia, meningitis and diarrhoea. It fits into a wider group of bacteria with the apt acronym of ESKAPE owing to their ability to avoid the effects of the drugs used against them.

Staphylococcus aureus (MRSA)

Probably the most famous hospital-acquired infection or 'superbug', MRSA is so-called because of its resistance to the antibiotic methicillin (hence Methicillin Resistant Staphylococcus Aureas). The bacteria are often carried on the skin or in the nose and throat and commonly lead to mild skin infections such as boils and impetigo. However, if the skin is broken MRSA can cause very serious blood poisoning. Thankfully, MRSA infection is decreasing in the UK because of better control methods and awareness by patients and hospital staff.

Streptococcus pyogenes

This bacterium, sometimes also known as 'Group A streptococcus', is responsible for a range of infections, but is commonly associated with sore throats (hence 'strep throat') and tonsillitis. Up to now, we have not seen this bacterium regularly developing resistance. To keep it this way, doctors don't usually prescribe antibiotics for sore throats (even those that may be caused by bacteria), unless the infection is particularly severe or you are at risk of a more serious infection, as they should generally clear up of their own accord.

Clostridium difficile

This bacterium, commonly known as 'C. diff', leads to infection of the digestive system resulting in diarrhoea, a high temperature and painful stomach cramps. Between 2004 and 2006 there was an outbreak of new strains of highly resistant forms of this bacterium, which quickly spread throughout the UK, US, Canada and Europe. The new strains are totally resistant to the antibiotic fluoroquinolone and reports suggest that resistance is also beginning to develop to alternative antibiotics.

Pseudomonas aeruginosa

Again, Pseudomonas probably won't be a bacterium that many people are familiar with, but it's one of the most common causes of pneumonia in hospitals, especially in patients with weakened immune systems and those on breathing machines. It's a particular worry for medical staff as it is very resilient and therefore has an 'inbuilt' resistance to antibiotics. In the US, it's estimated that there are 51,000 hospital Pseudomonas infections each year and more than 6,000 (13%) of those are multidrug-resistant.

So what can be done?

Antibiotic resistance is a problem we can all help to reduce. Good hand hygiene when visiting people in hospital helps. Only taking antibiotics when prescribed by a doctor, and listening to the advice of your GP about whether antibiotics are needed or not, are both very important. In addition, doctors themselves should only be prescribing these medicines when patients truly need them.

These may be small things, but if we all do them it will have an impact and maybe prevent a future where treatable diseases once again become potential killers.

It's also worth remembering that although this campaign is about better use of antibiotics, other microbes including parasites, viruses and fungi also evolve to evade our best treatments. Modern medicine is often something we take for granted, but it's important to consider that many drugs are not infallible and it's up to all of us to make them last as long as possible.

If you would like to read more about drug-resistant infections and what you can do to help, you might like to think about signing up to become an Antibiotic Guardian, following the progress of the Longitude Prize to develop better diagnostics for bacteria, or simply reading the World Health Organization's Antibiotic Awareness website.

Tackling drug resistant infections is also one of the Wellcome Trust's new priorities, which you can read about in our strategic approach. So watch out for more on this topic from us.