Infectious diseases are steadily becoming a global challenge with the emergence of Covid-19, Nipah, and deadly human bird flu (H9N2). Factors influencing the survival of microorganisms which spread the diseases include climatic change, poor sanitation, deforestation, urbanisation and change in lifestyle. Hemant Kumar Rout discusses with AIIMS Bhubaneswar executive director Prof Ashutosh Biswas, an expert in infectious diseases, on how to combat such diseases. Edited excerpts:
What are the current trends in infectious diseases in India and how have they evolved over the past decade?
Infectious diseases are the greatest enemy of human beings and it is a global challenge. The diseases can undermine the resilience of communities, drag them into poverty and have devastating consequences on the economy. There are several emerging infectious diseases trends observed over the past decades such as Covid-19, SARS, MERS, pandemic influenza, avian flu, swine flu, dengue, chikungunya, Zika, Nipah, scrub typhus, typhoid, leptospirosis, lyme diseases, hantavirus, hepatitis, HIV/AIDS, Crimean-Congo haemorrhagic fever, Kyasanur forest disease. Increasing trends of various resistant organisms such as e-coli, salmonella, MDR and XDR-TB and community-acquired pneumonia are also being observed.
Which infectious diseases pose the greatest public health threat in different regions of India, and why?
Vector-borne diseases such as dengue, chikungunya, malaria, zika, Japanese encephalitis, and scrub typhus poses a great public health challenge in almost all states in India. Drug resistance organisms have also become serious health challenges for higher morbidity and mortality.
How effective are current vaccination programmes in India against preventable infectious diseases?
Although a strong vaccination programme for children and new-borns for prevention of various infectious diseases is already in place, 100% vaccination coverage among children is doubtful. There are many vaccines which are usually taken during the adult period for prevention of infections. However, the adult vaccination programme is very much neglected among people because of lack of awareness. It is proven that some infections also cause cancer in humans and there are vaccines available to prevent these cancers if vaccinated on time.
What role does surveillance play in early detection and response to infectious disease outbreaks. How can it be intensified?
Disease surveillance on increase in known infectious diseases, atypical presentation of symptoms and early identification and correct diagnosis play a pivotal role to implement effective preventive and control strategies. The strategies help in terminating an outbreak at an early stage.
What interventions have been most successful in reducing the burden of infectious diseases in India?
There are various ways that microorganisms are transmitted from one person to another for spreading infections such as water borne, blood borne, vector borne, air borne, and droplets. Usually strategies and interventions are designed as per the mode of transmission of infections to reduce the burden of diseases. Therefore, various strategies at different levels should be strictly followed including human hygienic behaviour to reduce the transmission of diseases.
How can One-Health programme help India combat diseases?
Most important priority areas for research in infectious diseases are public health awareness regarding various top infectious diseases. This includes effective implementation of integrated information, education and communication programmes in the community for prevention and control of diseases. Newer diagnostic tools are needed for early and timely management of cases. Emerging multidrug resistance organisms due to irrational use of antibiotics is a big threat as we now need more new antibiotics to save lives. Antibiotic stewardship and infection control programmes at hospital and community should be strictly implemented and followed, while at the same time a national policy should be in place for rational use of antibiotics across the country.
Many infectious diseases have been transmitted from animals due to close interaction between humans and animals. Therefore, human health and animal health should no longer be treated as two separate subjects to prevent spillover infection. The One-Health programme is an initiative to promote health under one umbrella and to bring together medicine, veterinary and environment for better understanding and planning better effective strategies for prevention, control and management of infectious diseases.
How has climate change influenced the spread and prevalence of diseases? How does socioeconomic status impact the susceptibility and outcomes in different populations?
Climate change such as change in temperature, humidity and rainfall in a geographical area may invite more risk in spreading infectious diseases. Climatic conditions favour microorganisms to grow or multiply faster within or outside the human body. High prevalence of infectious diseases is mostly observed among the low socioeconomic groups due to various reasons. Therefore, prevention and control strategies should be more aggressively targeted in these groups of population in the community.