Rich people really do ignore you when they walk by: Study

Denser places, assumed by many to be more conducive to the spread of the coronavirus that causes COVID-19, are not linked to higher infection rates, say researchers.

The study, led by Johns Hopkins University, published in the Journal of the American Planning Association, also found that dense areas were associated with lower COVID-19 death rates.

"These findings suggest that urban planners should continue to practice and advocate for compact places rather than sprawling ones, due to the myriad well-established benefits of the former, including health benefits," says study lead author Shima Hamidi from Johns Hopkins Bloomberg School of Public Health in the US.

For their analysis, the researchers examined SARS-CoV-2 infection rates and COVID-19 death rates in 913 metropolitan counties in the US.

When other factors such as race and education were taken into account, the authors found that county density was not significantly associated with county infection rate.

The findings also showed that denser counties, as compared to more sprawling ones, tended to have lower death rates--possibly because they enjoyed a higher level of development including better health care systems.

On the other hand, the research found that higher coronavirus infection and COVID-19 mortality rates in counties are more related to the larger context of metropolitan size in which counties are located.

Large metropolitan areas with a higher number of counties tightly linked together through economic, social, and commuting relationships are the most vulnerable to the pandemic outbreaks.

According to the researchers, recent polls suggest that many US citizens now consider an exodus from big cities likely, possibly due to the belief that more density equals more infection risk.

Some government officials have posited that urban density is linked to the transmissibility of the virus.

"The fact that density is unrelated to confirmed virus infection rates and inversely related to confirmed COVID-19 death rates is important, unexpected, and profound," said Hamidi.

"It counters a narrative that, absent data and analysis, would challenge the foundation of modern cities and could lead to a population shift from urban centres to suburban and exurban areas," Hamidi added.

The analysis found that after controlling for factors such as metropolitan size, education, race, and age, doubling the activity density was associated with an 11.3 per cent lower death rate.

The authors said that this is possibly due to faster and more widespread adoption of social distancing practices and better quality of health care in areas of denser population.

The researchers concluded that a higher county population, a higher proportion of people age 60 and up, a lower proportion of college-educated people, and a higher proportion of African Americans were all associated with a greater infection rate and mortality rate.

Paris, Apr 17: Even as virologists zero in on the virus that causes COVID-19, a very basic question remains unanswered: do those who recover from the disease have immunity?

There is no clear answer to this question, experts say, even if many have assumed that contracting the potentially deadly disease confers immunity, at least for a while.

"Being immunised means that you have developed an immune response against a virus such that you can repulse it," explained Eric Vivier, a professor of immunology in the public hospital system in Marseilles.

"Our immune systems remember, which normally prevents you from being infected by the same virus later on."

For some viral diseases such a measles, overcoming the sickness confers immunity for life.

But for RNA-based viruses such as Sars-Cov-2 -- the scientific name for the bug that causes the COVID-19 disease -- it takes about three weeks to build up a sufficient quantity of antibodies, and even then they may provide protection for only a few months, Vivier told AFP.

At least that is the theory. In reality, the new coronavirus has thrown up one surprise after another, to the point where virologists and epidemiologists are sure of very little.

"We do not have the answers to that -- it's an unknown," Michael Ryan, executive director of the World Health Organization's Emergencies Programme said in a press conference this week when asked how long a recovered COVID-19 patient would have immunity.

"We would expect that to be a reasonable period of protection, but it is very difficult to say with a new virus -- we can only extrapolate from other coronaviruses, and even that data is quite limited."

For SARS, which killed about 800 people across the world in 2002 and 2003, recovered patients remained protected "for about three years, on average," Francois Balloux director of the Genetics Institute at University College London, said.

"One can certainly get reinfected, but after how much time? We'll only know retroactively."

A recent study from China that has not gone through peer review reported on rhesus monkeys that recovered from Sars-Cov-2 and did not get reinfected when exposed once again to the virus.

"But that doesn't really reveal anything," said Pasteur Institute researcher Frederic Tangy, noting that the experiment unfolded over only a month.

Indeed,several cases from South Korea -- one of the first countries hit by the new coronavirus -- found that patients who recovered from COVID-19 later tested positive for the virus.

But there are several ways to explain that outcome, scientists cautioned.

While it is not impossible that these individuals became infected a second time, there is little evidence this is what happened.

More likely, said Balloux, is that the virus never completely disappeared in the first place and remains -- dormant and asymptomatic -- as a "chronic infection", like herpes.

As tests for live virus and antibodies have not yet been perfected, it is also possible that these patients at some point tested "false negative" when in fact they had not rid themselves of the pathogen.

"That suggests that people remain infected for a long time -- several weeks," Balloux added. "That is not ideal."

Another pre-publication study that looked at 175 recovered patients in Shanghai showed different concentrations of protective antibodies 10 to 15 days after the onset of symptoms.

"But whether that antibody response actually means immunity is a separate question," commented Maria Van Kerhove, Technical Lead of the WHO Emergencies Programme.

"That's something we really need to better understand -- what does that antibody response look like in terms of immunity."

Indeed, a host of questions remain.

"We are at the stage of asking whether someone who has overcome COVID-19 is really that protected," said Jean-Francois Delfraissy, president of France's official science advisory board.

For Tangy, an even grimmer reality cannot be excluded.

"It is possible that the antibodies that someone develops against the virus could actually increase the risk of the disease becoming worse," he said, noting that the most serious symptoms come later, after the patient had formed antibodies.

For the moment, it is also unclear whose antibodies are more potent in beating back the disease: someone who nearly died, or someone with only light symptoms or even no symptoms at all. And does age make a difference?

Faced with all these uncertainties, some experts have doubts about the wisdom of persuing a "herd immunity" strategy such that the virus -- unable to find new victims -- peters out by itself when a majority of the population is immune.

"The only real solution for now is a vaccine," Archie Clements, a professor at Curtin University in Perth Australia, told AFP.

At the same time, laboratories are developing a slew of antibody tests to see what proportion of the population in different countries and regions have been contaminated.

Such an approach has been favoured in Britain and Finland, while in Germany some experts have floated the idea of an "immunity passport" that would allow people to go back to work.

"It's too premature at this point," said Saad Omer, a professor of infectious diseases at the Yale School of Medicine.

"We should be able to get clearer data very quickly -- in a couple of months -- when there will be reliable antibody tests with sensitivity and specificity."

One concern is "false positives" caused by the tests detecting antibodies unrelated to COVID-19.

The idea of immunity passports or certificates also raises ethical questions, researchers say.

"People who absolutely need to work -- to feed their families, for example -- could try to get infected," Balloux.

The Covid-19 pandemic has made an unprecedented impact on the Indian businesses, particularly small and medium enterprises (SMEs) and startups. According to a joint survey by FICCI and Indian Angel Network (IAN), the pandemic has hit the businesses of around 70% startups.

With uncertainty in the business environment and an unexpected shift in priorities of the government as well as corporates, many startups are struggling to survive, it says.

In a nationwide survey on the 'Impact of Covid-19 on Indian Startups' involving 250 startups, 70% participants said their businesses had been impacted by Covid-19 and around 12% had shut operations.

The survey shows only 22% startups have cash reserves to meet the fixed cost expenses over the next 3-6 months, and 68% are reducing operational and administrative expenses.

Around 30% of the companies said they would retrench employees if the lockdown was extended too long. The 43% startups have already started 20-40% salary cuts over April-June.

Over 33% startups said investors had put the investment decision on hold and 10% said the deals had been scrapped. Only 8% startups had received funds as per the deals signed before Covid-19 outbreak, the survey revealed.

The reduced funding has forced startups to put a hold on business development and manufacturing activities, which has resulted in loss of projected orders.

The survey highlights the need of an urgent relief package for startups, including possible purchase orders from the government, tax relief and swifter tax refunds, and immediate fiscal support measures, including grants, soft loans and payroll grants.

Besides 250 startups, 61 incubators and investors also participated in the survey.

While 96% of investors accepted that their investments in startups had been impacted by Covid-19, 92% said their investments in startups would continue to be low over the next six months.

Around 59% investors said they would prefer to work with the existing portfolio firms in the coming months. Only 41% said they would consider new deals.

"A comparison of priority investment sectors before and during Covid-19 shows 35% investors are now looking at investments in healthcare startups, followed by EdTech, AI/Deep Tech, FinTech and Agri," said the survey.

Around 44% incubators surveyed said their day-to-day operations had been considerably hit by Covid-19. Most incubators are now supporting their portfolio firms by providing them virtual platforms to interact with mentors, investors and industries.

Dilip Chenoy, FICCI Secretary General, said, "The startup sector is stressed for survival at the moment. The investment sentiment is also subdued and is expected to remain so in the coming months. Lack of working capital and cash flows may lead to major layoffs over the next 3-6 months."

Indian startups needed an enabling ecosystem and flow of funds to continue operations, the survey said.

Padmaja Ruparel, President, Indian Angel Network & Co-Chair of FICCI Startup Committee, said, "In these uncertain times, as investors, we must play an important role to provide the Indian startups funding, mentoring and hand-holding support to stay afloat and come out at the other end of this crisis."

To that end, IAN recently announced a debt fund to help IAN portfolio companies raise working capital and ensure business continuity by partnering with debt providers.

This must be replicated on a wider scale, so a larger number of startups are provided the capital support to make it during these tough times, Ruparel said.