"From an epidemiologic standpoint, I don't know if three weeks will be enough. It may require more time," said Venkayya, who was responsible for the development and implementation of the National Strategy for Influenza pandemic during the second term of the Bush administration.
"We will have to look at what is happening in other countries," he said.
"But if you were to ask me whether that will be enough given the size of the population, the healthcare capacity, the uniformity or lack of uniformity that is inevitable in a federated country like India where there's a lot of State autonomy on what to do and how to do it, and varying levels of compliance, I think this could easily go much longer," Venkayya said.
A three-week lockdown is a reasonable starting point to contain the coronavirus pandemic in a country like India, he said.
Since joining Takeda in 2012, he has established a high-impact vaccine pipeline that includes promising late-stage candidates for dengue and norovirus, gained through the acquisitions of LigoCyte and Inviragen Inc.
As head of Special Assistant to the President for Biodefense at the White House, he was responsible for the America's first development and implementation of the National Strategy for Pandemic Influenza in 2007. The White House published this federal guidance in 2007.
"It's now called the flattening the curve strategy. At that time, we called it a targeted layered containment and then it became called community mitigation. But the first flattening the curve graph was published in our federal guidance in 2007," he said.
"When I was in the white house, we were preparing for an influenza pandemic we realized that vaccines would not be available for many months after a pandemic started. And based on the 1918 experience, we expected there would be multiple waves of the pandemic and that for at least the first wave we would not have vaccines," he said.
As such, the White House team led by him had to find other ways to protect communities from this pandemic virus.
Based on some early modelling and additional modelling commissioned in 2006, they found the relevance of non-pharmaceutical interventions, community measures like closing schools and cancelling public gatherings, social distancing as well as isolation and quarantine for people that have been confirmed or suspected to have the virus.
"If you put all of these things together, and importantly if you did them early in a coordinated fashion, you couldn't have a very big impact on the transmission of the virus in a community," he said, adding that this guidance was published in 2007.
Emphasising the importance of doing these things early in the outbreak, he cautioned that else it would be much harder to prevent a large number of people from getting infected and accomplishing the goals of flattening the curve and delaying the peak of the curve.
"So here I think it's very important that India took (lockdown) action now, .. like many countries, there isn't widespread availability of diagnostic testing. And so it's hard to know how much virus is in any given community in India," he said.
"We also know that the threat is greater in India than it may be in other places because of the population density. Also, there are significant portions of the population that don't have access to the healthcare services that would be necessary to take care of large numbers of sick people. So, it (social mitigation measures) becomes even more important in India than it's important everywhere, Venkayya said.
Observing that none of the community interventions are perfect, he said if one puts a number of imperfect interventions together, then one can have a very significant positive impact on reducing virus transmission.
Prior to Takeda, Venkayya served as director of Vaccine Delivery in the Global Health Program at the Bill & Melinda Gates Foundation, where he was responsible for the Foundation's efforts in polio eradication and new vaccine introduction.
Globally, the novel coronavirus has killed 108,862 people and infected over 1.7 million people globally. The US has the highest number of infections at 529,887, according to Johns Hopkins University data.
In India, the number of confirmed coronavirus (Covid-19) cases is now 8,504 and the death toll has reached 289, according to the Worldometer.
The country reported 34 deaths and 909 new positive Covid-19 cases in the last 24 hours, said the Ministry of Health and Family Welfare.
West Bengal became the sixth state in India after Odisha, Punjab, Maharashtra, Karnataka and Telangana to extend the coronavirus-induced lockdown till April 30.