An average of 80,000 Covid-19 cases were reported each day in April to the World Health Organization, the top UN health agency has said, noting that South Asian nations like India and Bangladesh are seeing a spike in the infections while the numbers are declining in regions such as Western Europe.

WHO director-general Tedros Adhanom Ghebreyesus said on Wednesday that countries must also be able to manage any risk of the disease being imported into their territories, and communities should be fully educated to adjust to what will be a 'new norm'.

He said as the countries press forward in the common fight against Covid-19, they should also lay the groundwork for resilient health systems globally.

'More than 3.5 million cases of Covid-19 and almost 250,000 deaths have now been reported to the WHO. Since the beginning of April, an average of around 80,000 new cases have been reported to the WHO every day,' Ghebreyesus said in Geneva Wednesday.

Asserting that the virus cases were not just numbers, he said: 'every single case is a mother, a father, a son, a daughter, a brother, sister or friend'.

He said while the numbers are declining in Western Europe, more cases are being reported every day from Eastern Europe, Africa, South-East Asia, the Eastern Mediterranean and the Americas. Even within regions and within countries, there are divergent trends, the agency added.

While some countries are reporting an increase in Covid-19 cases over time, many have seen caseloads rise because they have ramped up testing, the WHO official said.

'We've also seen in Europe and Western Europe a fundamental decrease in the number of cases, but we have seen an associated increase in the number of cases reported in places like the Russian Federation. Southeast, the Western Pacific areas are relatively on the downward trend like Korea and others, but then we do see in South Asia, in places like Bangladesh, in India, some trends towards increase.

'So it's very difficult to say that any particular region is improving or (not improving). There are individual countries within each region that are having difficulties getting on top of this disease and I am particularly concerned about those countries that have (an) ongoing humanitarian crisis,' WHO's executive director Michael Ryan said.

The death toll due to Covid-19 in India rose to 1,783 while the number of cases climbed to 52,952 on Thursday, registering an increase of 89 deaths and 3,561 cases in the last 24 hours, the Union Health Ministry said.

The number of active Covid-19 cases stood at 35,902 while 15,266 people have recovered, it said.

Noting that while seeing an increase in the number of cases is not good in terms of transmission, WHO's Emerging Diseases and Zoonoses Unit head Maria Van Kerkhove said: 'but I don't want to equate that with something (being) wrong'.

'I want to equate that with countries are working very hard to increase their ability to find the virus, to find people with the virus, to have testing in place to identify who has Covid-19, and putting into place what they need to do to care for those patients,' Kerkhove said.

With more countries considering easing restrictions implemented to curb the spread of the coronavirus, the WHO has again reminded the authorities of the need to maintain vigilance.

'The risk of returning to lockdown remains very real if countries do not manage the transition extremely carefully, and in a phased approach,' Ghebreyesus said.

He urged countries to consider the UN agency's six criteria for lifting stay-at-home measures.

That advice includes ensuring surveillance is strong, cases are declining and transmission is controlled. Health systems also must be able to detect, isolate, test and treat cases, and to trace all contacts.

Additionally, the risk of outbreak in settings such as health facilities and nursing homes needs to be minimised, while schools, workplaces and other public locations should have preventive measures in place.

'The Covid-19 pandemic will eventually recede, but there can be no going back to business as usual. We cannot continue to rush to fund panic but let preparedness go by the wayside,' he said.

He said the crisis has highlighted the importance of strong national health systems as the foundation of global health security: not only against pandemics but also against the multitude of health threats that people across the world face every day.

'If we learn anything from Covid-19, it must be that investing in health now will save lives later,' Ghebreyesus said.

While the world currently spends around USD 7.5 trillion on health annually, the WHO believes the best investments are in promoting health and preventing disease.

'Prevention is not only better than cure, it's cheaper, and the smartest thing to do,' he said.

The deadly coronavirus, which originated from the Chinese city of Wuhan in December last year, has infected over 3.7 million people and killed 263,831 people globally, according to a tally by Johns Hopkins University.