Viruses and Bacteria, Friends or Enemies of People?

Sreekumar Raghavan

Each living organism on earth whether it is a single celled or multicellular, plants, trees and animals have a role to play. In the wild, many species are dependent on each other for survival but from our ecological point of view they maintain a balance. The ferocious animals such as the lion and the tiger usually pounce on herbivores or plant eating animals for food and thus help maintain a balance of our plant resources. The Project Tiger was initiated in India to raise the tiger population. A century ago, the planet had one lakh tigers in the wild but by 2014 India had only 2200 tigers which has now risen to 3000. This was possible by creating more reserves for breeding, preventing poaching by introducing tougher sentences for poachers. Destruction of forests to make way for mining or for urbanisation is leading to loss of habitat for our wild animals. 
Exposure to Viruses
Loss of forest cover not only destroys the habitat of animals and also lead to climate changes but also exposes mankind to several new types of viruses for which we don't have any immunity at all. This warning was given atleast two decades ago in a cover story in the US magazine Newsweek and the risk of mutations are also higher for some types of viruses. Then the question naturally arises as to how viruses survive in monkeys, chimpanzees, bats while it causes harm in humans? It could only be a symbiotic relationship where both are dependent on each other for survival. Just as carnivorous wild animals help prevent overgrazing of the forest land by herbivores, such wild animals should also be kept in check lest they also end up short of food. Hence, viruses that exist in the harmless animals such as bat, pangolins and monkeys may be released when there is too much hunting by the ferocious ones. 
It is said about the snakes that they are far more afraid of humans that humans are of snakes but most often we knowingly or unknowingly hurt them and in the process get a bite that can prove deadly. Likewise, we invite viruses into our lives when we go hunting for bats, pangolins, squirrels, monkeys and wild pigs and other animals. This is increasing at a faster rate than before and destruction of forests for development expose ourselves to the wild and loss of habitat for flora and fauna. 
All viruses and bacteria aren't harmful for us-there are several good ones around. There are several of them that cause common cold but is ejected by our body wit in five days to a week. There are friendly ones like the Lactobacillus bacteria that survive in our digestive, genital and urinary systems and which break up sugars into lactic acid. They also help us fight diseases in the digestive system such as diarrhoea. Then we find certain types of bacteria that digest the organic waste to convert them into manure. Foods are damaged by bacteria when it is kept at room temperature. 
Virology
Virologists are engaged in the identification of new viruses but it is not a simple exercise in terms of effort and cost. Once the strains are identified, new molecules of drugs or existing molecules are tested on them to find out its effectiveness in dealing with them. Simultaneously, pharma companies also invest heavily in developing vaccines if there is potential for marketing it over a long term.
The challenge before policy makers world-wide is our inability to ward off some viruses and bacteria which are coming back with a vengeance causing misery all around especially in less developed nations. This includes tuberculosis, scarlet fever, polio, measles and diarrhoea. It is estimated that 10 million people world-wide are affected by TB and 1.5 million died in 2018. Communicable diseases ranks among the number one killers worldwide compared to non-communicable diseases (NCDs). But treatment facilities and medicines are available for NCDs than communicable diseases. Therein lies the proportionately high investment nations make in tertiary health care compared to public health. 
Public Health Challenge
In the outbreak of communicable diseases such Nipah or Covid-19, the public health system is put under tremendous strain. In such cases, nations or states with a well-developed decentralised network of hospitals and treatment centres will be able to rise up to the occasion as in the South Indian state of Kerala. Several million children used to die in African countries due to diarrhoea when a simple solution like a pinch of salt and eight pinches of sugar in water could contain the disease. WHO has now reiterated that preventive measures are most important to contain TB.
Future Concerns
What is worrying policy makers is the shorter leg of epidemic attacks compared to a few in a century which was the trend before. There has to be stricter regulation on poaching of wild animals for meat and medicinal purposes. Secondly, more investment may have to be carried out to identify virus strains as we become more exposed to wild life and we don’t have the immunity against them. Investment in public health should match the investments in teritiary care if epidemic or pandemic outbreaks have to be dealt with on a firm footing.