The Revised National TB Control Programme (RNTCP) that came into being in 1997 has to its credit some enviable accomplishments. For instance, it achieved country-wide coverage in March 2006 and achieved 86 per cent treatment success rate in recent years. More than 15,000 suspects are examined for the disease every day and about 3,500 patients are started on treatment. And to its credit, for the very first time in 2007, RNTCP achieved the global target of 70 per cent case detection (53 cases per 100,000 population per year).
Despite these impressive achievements, India has the highest TB burden in the world — 3.5 million active TB cases. The number of new active TB cases detected every year is over two million; it was 2.2 million in 2011. And the disease kills two people every three minutes. Incidentally, the incidence and prevalence figures are not a true indicator of the ground reality — the number of patients treated by the private sector is not known.
But why is India continuing to record the most number of TB patients in the world every year? A closer inspection reveals that the programme is far from perfect and may require thorough re-examination of both design and implementation. The massive country-wide drug stock-out crisis that played out recently is, but, just one of the malaises that the programme faces.
To start with, is the programme identifying and treating all the patients? The national TB control programme (RNTCP) uses a passive system for diagnosing TB patients. The design of the system is such that it waits for patients to walk into the centres to get tested. It is well known that patients walk into these centres quite late in the day. And in the process, they end up infecting many people. That a single active TB patient who is not on treatment is capable of infecting 10 or more people in a year shows how badly our RNTCP programme is in need of a reorientation. It has to necessarily shift gears and seriously consider changing its strategy from the current passive case-detection system to an active mode of detecting cases.
How far we are from even contemplating a radical change in our case-detection approach can be assessed by looking at how the WHO-recommended, RNTCP-approved contact screening of children below five years in households where an adult has been recently diagnosed with active pulmonary TB (sputum smear positive) is carried out. Children below five years from such households are most vulnerable to getting infected and probably developing active TB.
As a preamble, one has to only examine the differences between the WHO guidelines and the RNTCP guidelines to understand the extent of disconnect. While the WHO recommends contact screening in children below six years, RNTCP has it as below five years!
Screening children would help in diagnosing those who have already developed the disease (active TB) as well as those who have been infected but yet to develop the disease. While treatment for those who have developed the disease would be through the routine multi-drug regimen, children who have been infected but have not yet developed the disease are ideal candidates for a preventive therapy.
Children who are infected but have not yet developed the disease may not have symptoms like history of cough and/or fever and/or weight loss and/or weight gain. The use of a single drug — isoniazid — daily at 10 mg/kg for six months would “greatly reduce the likelihood of developing TB during childhood,” the WHO guidelines note.
According to WHO, the risk of developing the disease is “much greater” in infants and those below six years who have been infected than those above the age of six. In infected children below six years, if the disease does develop, it usually does so “within two years of infection.” But in the case of infants, the disease can set in within a matter of 6-8 weeks of infection.
“Children below six years have more chances of developing active TB after exposure and also more chances of developing severe disease (disseminated TB, meningitis),” Dr. Soumya Swaminathan, Director of the Chennai-based National Institute for Research in Tuberculosis (formerly TRC) noted in her email to this Correspondent.
A 15-year follow-up study of household members in a rural community in south India found that unlike adults, children in the age group 0-4 years had seven times higher risk of developing infection when an adult had smear positive TB.
Hence, contact screening of young children combined with chemoprophylaxis (preventive drug therapy) would go a long way in breaking the TB transmission cycle and reducing the case load by preventing the number of people who would become TB patients.
And the best part is that contact screening does not require much additional resources and can be implemented through the existing system if compliance is ensured through adequate monitoring and supervision.
However, a few studies undertaken in India provide ample evidence that routine contact screening of children below five years is sub-optimal in operation and is not carried out as per guidelines. A 2009 study carried out in four TB units (two in Chennai city and two in rural Vellore district) by V.V. Banu Rekha et. al., of NIRT, Chennai, provides some insights into the state of contact screening of children below six years.
Only 14 per cent of children aged 6-14 years were screened for TB and only 19 per cent (16 of 84 children) of children below six years were initiated on preventive therapy. There was no difference between urban and rural areas in terms of preventive therapy initiation.
Even the awareness level among health care workers (HCW) was sub-optimal. “Poor awareness,” is how Dr. Swaminathan describes the awareness level among HCWs. “Two studies — in Tamil Nadu and Andhra Pradesh — have shown very low uptake of screening and chemoprophylaxis. Other district TB officers also report similar status,” Dr. Swaminathan noted.
Worse, health-care workers in rural areas were themselves less aware of contact screening and preventive therapy in young children. Awareness level among HCWs that immediate family members are more susceptible to infection was “significantly lower” in rural areas. Only one-third of parents in rural areas were aware of contact screening and the need for preventive therapy in children below five years. “It has not been prioritised by RNTCP. No reporting of this activity is required,” she said explaining the sorry state of affairs.
Shockingly, the DOTS TB treatment card of the adult (index patient) has no provision for documenting the details of contact screening, preventive therapy, follow-up and treatment completion.
In a follow-up study conducted in the same areas between October 2009 and August 2011 by the team led by Dr. Swaminathan, all the health workers — medical officers to DOTS workers — were provided basic training on all aspects of contact screening and preventive therapy. And a separate preventive therapy register and card were also introduced in line with the WHO recommendations.
A 2013 study reveals that the results were quite dramatic. The health workers were also able to identify 82 per cent of child contacts. Sixty-one per cent (53 children below six years) were screened for TB disease and put on preventive treatment. Of the 53 children, 74 per cent (39 children) completed the treatment. This is a huge improvement compared to just 19 per cent children who were even initiated on treatment in 2008.
“Parents need counselling and explanation; they do accept if told properly,” is how Dr. Swaminathan explains how receptive parents are in starting preventive treatment in young children.
(The Correspondent is a recipient of the 2013 REACH Lilly MDR-TB Partnership National Media Fellowship for Reporting on TB. The article is the first of a series to be written on “Contact screening of children below six years in households with newly diagnosed active TB patients.”)