Faulty Surveillance - Influenza

What is the issue?

• India's surveillance system on the influenza cases seems to be flawed.
• Given the mortality rate, it is essential to make corrections to take the right policy decisions.

What is the anomaly?

• Ever since the first occurrence of H1N1 influenza in India during the 2009 pandemic, annual outbreaks are usual.
• This year the virus has been particularly active.
• The recent number on mortality is at 1,873.
• However, the official figures show it to be a relatively better year in terms of low death toll.

What are the flaws in surveillance?

• Number Data - The problem is that the official figures capture only the H1N1 numbers.
• But influenza was present in India even before 2009 in the form of H3N2 and Influenza B virus types.
• Notably, H3N2 is capable of causing outbreaks as big as H1N1.
• And yet India does not track H3N2 cases as extensively as it does H1N1.
• Data from other sources have established that influenza accounts for a considerable percentage of fever cases.
• These are often undiagnosed and classified as “mystery fevers”.
• Sequence data - India submits a small number of H1N1 genetic sequences to global open-access databases given its size and population.
• Sequencing is important because it can detect mutations in genetic material.
• As mutations help the virus evade human immune systems, it is essential for understanding the lethality of the virus.

What is the impact?

• These flaws consequently translate to the vaccination decisions.
• e.g India falls out in vaccinating even high-risk groups such as pregnant women and diabetics.
• The antiviral medicine, Oseltamivir, is of doubtful efficacy unless administered early enough.
• So vaccination is a crucial instrument for India to handle the influenza menace.
• A better surveillance of influenza will possibly reveal the true scale of this public health issue and aid in right policy decisions.

Source: The Hindu