The world has been on tenterhooks ever since the extent of the Ebola crisis became known. Despite its initial slow response, the global health community has been able to coordinate an effective international response to stem the spread of the Ebola virus in West Africa. With the emergency response slowing down, just enough for the affected countries to begin with the onerous task of rebuilding their health systems, the world has now been hit by another public health challenge with the spread of the Zika virus in South and Central Americas.
While it causes only mild fever in humans that lasts two to seven days, with skin-rashes and other symptoms similar to dengue and chikungunya, the sudden increase in reported cases of microcephaly is adding to the concerns around Zika. Microcephaly is a rare condition where babies are born with smaller heads and often severe cognitive disabilities. The Brazilian government is currently investigating approximately 3,670 suspected microcephaly cases and their link to Zika. Besides microcephaly, the Brazilian government has also reported an increased number of people affected with the Guillain-Barré syndrome in which a person’s own immune system damages the nerve cells.
It must be noted that Brazil was able to identify these cases only due to its effective disease surveillance and health systems.
Alongside Brazil, the Colombian president has also announced that more than 3,100 pregnant Colombian women are infected with the mosquito-borne Zika virus.
What makes the spread of Zika even more worrisome is the ubiquity of the Aedes mosquito which acts as the carrier of the virus. Various species of the mosquito are present across the world and cause a host of tropical diseases in densely-populated regions such as South Asia, including India. Since there have been reported cases of sexual transmission of the virus, the prospect of further contagion, facilitated by infected international travellers and the upcoming Olympic Games in Brazil, is adding to the grave concerns around Zika. As per recent updates, China has confirmed its first case, with a Chinese citizen who travelled to Venezuela testing positive for the Zika virus.
The World Health Organization has declared Zika a public health emergency. This will go a long way in shoring up international efforts to stop the virus’ spread, generating consistency in the research efforts to better understand the nature of the virus, and mobilising the necessary sources to develop the right diagnostics and vaccines.
However, Zika may just be one of the many to come. Researchers have predicted that the effects of climate change and rising temperatures will lead to frequent and much more severe outbreaks of existing and newer vector-borne diseases. The international community and national policy-makers must take this view into consideration and invest towards pandemic preparedness to ensure that these outbreaks do not spiral into national or international public health emergencies.
To prepare ourselves against Zika in India, we can ramp up our sanitation programmes and integrated vector-control efforts to reduce the numbers of the Aedes mosquito. Additionally, we can operationalise an early warning system, as well as activate a sentinel surveillance system — similar to the one we have for dengue — to track cases of the viral infection. We can also leverage technologies such as the Plaque Reduction Neutralization Test for detecting and measuring antibodies that can neutralise the Zika virus.
Most importantly, considering that vaccines are a cornerstone of the preventive healthcare efforts, we can urgently develop a potent vaccine against the Zika virus.
Zika and its possible link with microcephaly have galvanised international attention and led to a race against time to develop candidate vaccines to prevent further damage. A consortium of organisations — including Canada’s Laval University, the University of Pennsylvania, Inovio Pharmaceuticals Inc. and GeneOne Life Science Inc. — is already working on a vaccine which could be ready for emergency use before the end of this year.
While, not the most opportune, this is a timely reminder of the value of vaccines in reducing human suffering caused by preventable diseases, and in generating economic value by averting morbidity and mortality. Vaccines are one of the most cost-effective health interventions available to mankind, and it is imperative that we fully leverage them for the value that they can provide. India has been able to build thriving vaccines and biological ecosystems — the country is already one of the largest suppliers of vaccines to the United Nations’ system of agencies. Building on their cost-competitiveness and talent pool, the Indian vaccine manufacturers are now moving up the innovation value-chain and developing vaccines for neglected tropical diseases such as dengue, chikungunya, etc. We must ensure that while we make for the world, we also work towards making Indian citizens and policy-makers realise the great benefits of introducing new vaccines and expanding access to immunisation services, especially to those belonging to the most vulnerable sections of our society.
There is no doubt that vaccine research and development would again become the centrepiece of the efforts to contain the spread of Zika. India must seize this opportunity to impress upon the various stakeholders the critical role of vaccination as a comprehensive preventive healthcare strategy that may be needed more and more in the years to come.
NK Ganguly is a visiting professor of eminence, Policy Centre for Biomedical Research, Translational Health Science and Technology Institute
The views expressed are personal