Traditionally there have been no anti-viral drugs. Viral infection are normally cleared by body's immune system. Also, our body produces very effective anti-viral like interferon etc. On the other hand, bacterial infections are treated with antibiotics and normally without properly ascertaining whether or not there is need for that. Thus the continued exposure of bacteria to antibiotic places tremendous selection pressure on it to develop resistance for survival in line with natural law of adaptation and evolution.

Ashok, Good thought. When our body produces very effective anti-viral like interferon, why does it not produce any anti-bacterials?

Can we really say that body does not produce any anti-bacterials? Body fluids, such as tear, saliva, mucous etc. have antibacterial activities. Further, an efficient immune system effectively deals with the invading pathogens with range of arsenals at its disposal. The outcome is that most of the infections that we come in contact with everyday, are cleared away. However, the bacterial pathogens have also evolved measures to counter the immune defence system and in a given situation like a weaker immune response from the body for some reason (e. g. an stressful, too fast and tense routine of the day or bad foof affect), the bacteria are able to set them up and cause the disease. In most cases though such infections would also be cleared away eventually with necessary modifications in food, drink and life style. So normally we do not need external agents, such as antibiotics, to treat ourselves. A rough estimate suggests that use of antibiotics in about 50% of cases is NOT necessary. It is because of such undesirable use, over-use, mis-use etc of antibiotics in hospitals, agriculture and veterinary practices that we are facing serious challenge in dealing with drug-resistant bacterial pathogens today.

Ashok, You are absolutely right. Prescribing antibiotics when they are not needed, or prescribing antibiotics without testing for culture and sensitivity or inadequate dose or inadequate duration of antibiotics may all lead to antibacterial resistance. In addition, antibiotics given to animals and consumption of the meat by humans may also be other causes of antibacterial resistance. These may cause intereference with the antibiotic treatment when it is absolutely essential. I might add non-compliance in patient population taking antibiotics may add to this problem.

Omer, thanks for your observation and comments above. An other point to bear in mind while considering lower frequency of developing resistance against anti-viral agents by viruses, is that the biology bacteria and viruses are hugely different. While bacteria is a complete organism in its own right carrying out full range of activity of a living systems, viruses are merely matter and molecules outside the host. Viral functions are expressed only when they find their way into a suitable host. So their genetic ability is limited in comparision to bacteria in that sense.

Having said that, we can not presume viruses to be any weaker or less smart entities. Their genome mutate rapidly to dodge host immune system. They have evolved complex mechanisms of overcome host defence and established them self strongly in human body producing terrible diseases. Good example of these are HCV and HIV viruses for which we haven't been able develop dependable less toxic drugs that could cure the ailments.

It's not true, especially with RNA virus. You can take for example HIV.

Viruses score over bacteriae in that they are extremely efficient in rapidly adapting to the host immune system and bypassing it. Antiviral resistance- eventhough developing now- is still not as rampant as antibacterial resistance- simply because more often than not- viral infections are allowed to run through the illness course completely, and no extrinsic drugs are provided in almost 90% of the cases. The virus therefore does not need to modify its responses to any agent.

Antibacterials on the other hand- are a completely different scenario altogether- there is no denying that antibiotics are prescribed very frequently in out-patient settings, and even for simple illnesses. A thorough knowledge of infection sources, most likely organisms and appropriate therapy and targeted antibiotic therapy can go a long way in reducing resistance development.

Indrajit,

You are right. The antiviral resistance is on the rise. For malignancy every now and then you hear of a new antiviral drug is because of the resistance with the previous one. Thanks for your input.