The third Covid-19 wave in India has been largely powered by an exponential rise in cases in the three big metro cities of Mumbai, Delhi and Kolkata, but the rest of the country has not been immune to it.

Several smaller cities and towns, particularly in the states of Bihar, Uttar Pradesh and Jharkhand, are witnessing dramatic surges after months of barely reporting any cases.

Bihar has reported 6,560 new cases in the last one month starting December 6, a staggering 5,400% rise compared to the 30 days before that when it reported a mere 115 cases.

Neighbouring Uttar Pradesh is witnessing a similar massive surge. India’s most populous state reported 300 new cases in the 30 days between November 6 and December 6. But from December 6 to January 6, the corresponding number shot up to 8,797, a growth of nearly 3,300%.

Jharkhand has seen an even bigger jump in cases: 488 cases between November 6 and December 6, and 15,870 in the next 30 days.

On December 3, India confirmed its first case of the highly infectious Omicron variant of the coronavirus, which was detected in South Africa in November. Since then, over 3,000 Omicron infections have been found in the country, with the variant accounting for the bulk of samples sequenced in Delhi and Mumbai.

Outside of these cities, genome sequencing efforts remain patchy, making it hard to draw firm conclusions about the spread of Omicron. While some officials in Bihar and Jharkhand claimed the rise in Covid-19 cases was an outcome of increased testing in December, there are reasons to believe the new variant has played a role in the surge.

Not just urban centres

While a large number of cases in Uttar Pradesh are being reported from districts bordering Delhi, district-wise data of Bihar and Jharkhand indicate that the new variant has spread beyond urban centres.

In both states, the capital cities, Patna and Ranchi, may account for the largest share of cases but many rural and semi-urban districts are witnessing a surge too, data shows. This after many months of negligible new cases.

For instance, Gaya, in south Bihar, has seen one of the steepest increases in cases in the entire country. In the last one month, the district has reported 651 new cases, up from just one case reported in the previous month.

In Jharkhand, several districts have reported sudden steep spurts in cases. Chatra and Giridih, for instance, did not report any cases in November at all. But since December 6, both districts have reported over a hundred cases each.

Similarly striking is the case of Koderma. From a sum total of two new cases from November 6 to December 6, the number went up to nearly 800 cases in the subsequent 30 days.

Lack of surveillance

Officials in both states say there is no evidence to link the current surge to Omicron.“The report that we have just received says there is no Omicron,” said Arun Kumar Singh, Jharkhand’s additional chief secretary (health and family welfare), referring to the genome sequencing results.

State officials in Bihar did not respond to queries, but district officials in Gaya said the Omicron variant had not been found in any of the samples sequenced from there.

Yet, that may simply be a result of inadequate sequencing capacities. Genome sequencing in India is done by a network of 38 laboratories. Most of these laboratories are in southern India.

Singh, the Jharkhand official, said the state had no sequencing capabilities at all. “We send samples to Bhubaneswar and it usually takes 45 days for results to come,” he said.

Bihar, too, was dependent on laboratories in Kolkata and Bhubaneswar until earlier this week. It got a lab of its own only last Monday.

Health experts from the state believe that the sudden surge of cases was a clear sign that the highly-contagious variant was likely to be widely present, and that it had gone largely undetected was a reflection of the state’s poor surveillance regime.

Indeed, in Gaya, a health official said a lot of the early cases had travel history from Mumbai where Omicron is the dominant strain. “They gave it to their contacts and now there is community spread,” said the official.

But in Jharkhand, Koderma’s chief medical officer Dr DP Saxena said the rise in cases was simply a result of more testing. “Now the government is saying to do more testing, so there will be positive cases,” he said. “We are testing people who are coming to the Koderma railway from different places so that’s also adding to the numbers.”

Jharkhand’s current test positivity rate is now 6%, significantly up from the level of around 0.1% where it hovered around for most of November.