I, as a writer of this essay, dream of a day where I wake up to see TB being successfully eradicated. Should I dream of it? Why not! Should I strive for it? Absolutely so!!
It is important that we know the difference among control, eliminate and eradicate before exploring why tuberculosis has not been eradicated till date. Disease control refers to the decrease in new cases, existing cases and the consequences of the disease in terms of morbidity and mortality to an extent which the public can accept. To eliminate means to bring such control levels to zero in certain areas. The word eradicate has a slightly higher weight, as it implies that we are permanently eliminating the disease. In accordance with the above definitions, it is a well known fact that controlling and eliminating the disease is fairly achievable over eradication with steady interventions and active surveillance. However, many countries shift their interests and reduce their investments after the disease incidence and prevalence has dropped down. The altered focus of the government then leads to the disease being reenergised with its target being the vulnerable people. This vicious cycle then continues in the population, and is in essence exactly what has been happening in the context of tuberculosis in most nations, particularly developing nations like those in the southeast Asia, Africa and the eastern Europe.
To eradicate a disease, we must understand the disease’s epidemiology, different strategies to intervene and determine if the disease is really amenable to eradication. As far as tuberculosis is concerned, it is an uphill task, something that might seem practically impossible to eradicate. The disease spreads easily from person to person and does not follow a specific pattern like influenza, which occurs cyclically down the year. The disease itself is also hard to be identified as WHO report shows that for every 2 cases diagnosed, the third is freely walking in the community undetected. Following an infection, unlike in the cases of measles or chickenpox, immunity is not gained by the person. Similarly, the disease relapse also parallels in the same ratio as those who are getting treated completely. There is always a possibility that the disease can re-emerge in an individual in any calendar of a person’s life. Furthermore, there is not a nation in the globe that has even declared the disease to be deliminated. Thus eradication is currently not only a distant scenario, but also very far frombeing achieved in the foreseeable future.
Vaccination is always an important strategy to eliminate or eradicate the disease that has caused much of a burden for us. The currently available bCG vaccine has been used for over hundreds of years with billions of shots being administered which protects individuals from a severe childhood disease like tuberculous meningitis, yet it does not prevent the most prevailing form of the disease- pulmonary disease in adults. New vaccines
have not been developed till date, possibly due to a muddy understanding of how the protective immune system governs in terms of tuberculosis, or it maybe due to the fact that the disease itself has a complicated biology. Presently available standard drug regimens to control tuberculosis are effective to say the least, but they come at the cost of being toxic with a prolonged duration of treatment. The organism is also slowly growing and intracellular, and there are only a few drugs that can target them. With improper adherence to treatment regimes, drug resistance has been a rampant issue . In order to combat these, the new regime encompasses even more toxic drugs, and this not only increases the duration of treatment, but also leads to an additional degree of financial burden in vulnerable and immunocompromised people.
Newer diagnostic tools are required which can, in addition to finding the disease early, also detect its latent form, determine drug sensitivity testing for drugs other than the standard first line regime, and aid in detection of the disease in paediatric populations. Many novel procedures are undergoing investigations and trials, so have not been produced in a large scale. Hence people are still being evaluated by the older sputum smear microscopy tests in order for the treatment to begin.
So what now? The End TB Strategy has aimed to reduce the mortality due to TB related issues and decrease the incidence of disease by 90% and 80% respectively by the year 2030. It intends to make the world TB free with no more deaths and suffering from this chronic disease. Despite practically being far from achievable, continuous determination, investment and intervention can draw us closer to that vision. The largest burden of TB compromises the socially and economically backward groups of population, and thus they should be the target of concern by reducing poverty as well as addressing the educational aspects and barriers to good health among these groups. Greater political commitment along with quite a large sum of financial investment always remains the key to do so. As newer issues have also been brought up due to multidrug resistant TB, newer diagnostic modalities along with drugs that do more benefit than harm, plus side by side health promotion and health personnels getting trained to counter such problems should be sought for. Treatment and protection for theimmunocompromised and vulnerable people should never be far from our mind. Moreover, mucosal surfaces of the lungs should be the target of vaccine for disease prevention, something which is not rendered by the current available vaccine. Thus I, as a writer of this essay, dream of a day where I wake up to see TB being successfully eradicated. Should I dream of it? Why not! Should I strive for it? Absolutely so!!