A 25-year, US$10-billion global effort has taken the number of polio cases from hundreds of thousands per year to just hundreds, but it is now struggling to stamp the virus out of its final strongholds in Pakistan, Afghanistan and Nigeria, where transmission has never been interrupted. Of these, Nigeria was the only one to see an increase in cases from 2011 to 2012, and public-health experts worry that the virus's recalcitrance here will prevent global eradication, and eventually lead to a wider resurgence of the disease.

Kyasanur forest disease (KFD), a tick-borne viral disease with hemorrhagic manifestations, is localised in five districts of Karnataka state, India. Annual rounds of vaccination using formalin inactivated tissue-culture vaccine have been conducted in the region since 1990. Two doses of vaccine are administered to individuals aged 7–65 years at an interval of one month followed by periodic boosters after 6–9 months. In spite of high effectiveness of the vaccine reported in earlier studies, KFD cases among vaccinated individuals have been recently reported.

Seasonal outbreaks of acute encephalitis syndrome (AES) occur with striking regularity in India and lead to substantial mortality. Several viruses, endemic in many parts of India, account for AES. Although Japanese encephalitis virus (JEV) is a key aetiological agent for AES in India, and has attracted countrywide attention, many recent studies suggest that enteroviruses and rhabdoviruses might account for outbreaks of AES. We did a systematic review of published studies to understand the changing landscape of AES in India.

Viral hepatitis constitutes an enormous health burden, and is a major cause of morbidity and mortality globally. The magnitude of the problem can be highlighted by the fact that 1 in 12 people globally are living with chronic infections of either hepatitis B

An engineered influenza virus based on a haemagglutinin protein from H5N1 avian influenza, with just four mutations, can be transmitted between ferrets, emphasizing the potential for a human pandemic to emerge from birds.

Highly pathogenic avian H5N1 influenza A viruses occasionally infect humans, but currently do not transmit efficiently among humans. The viral haemagglutinin (HA) protein is a known host-range determinant as it mediates virus binding to host-specific cellular receptors1, 2, 3. Here we assess the molecular changes in HA that would allow a virus possessing subtype H5 HA to be transmissible among mammals.