Madhubani, where 98,175 migrants returned to, has reported 718 Covid-19 cases so far. East Champaran saw the return of 93,292 migrants and has reported 678 cases. (File)

When migrants started returning to Bihar on Shramik special trains, private vehicles and even on foot, the state government had raised an alarm about the potential spread of infection and started quarantining them.

The state government’s daily health bulletin then showed how migrants accounted for more than half of the positive cases.

But in the ongoing surge in cases in Bihar, the numbers tell a different story. While the Covid-19 cases in Bihar climbed from 10,250 on 1 July to 30,066 on July 22, only two of top 10 migrant recipient districts are now among the 10 districts with the highest case counts.

The districts with the maximum number of cases now are Patna (4,479), Bhagalpur (1,859), Muzaffarpur (1,382), Siwan (1,154), Nalanda (1,143), Begusarai (1,114), Gaya (1,070), West Champaran (913), Rohtas (1,051) and Nawada (898). Out of them, 21,433 migrants returned to Patna and 73,769 to Gaya.

The other districts where a large number of migrants returned have reported fewer cases.

Madhubani, where 98,175 migrants returned to, has reported 718 Covid-19 cases so far. East Champaran saw the return of 93,292 migrants and has reported 678 cases. Katihar, which received 85,797 migrants, has 619 cases. Darbhanga, where 76,556 migrants returned, has 545 cases. West Champaran, which saw the return of 62,737 migrants, has 913 cases. Araria, where 60,926 migrants returned, has 300 cases, Rohtas, where 59,739 migrants returned, has 1,051 cases, 59,171 migrants returned to Purnia and it has reported 634 cases and Samastipur, where 54,505 migrants returned, has reported 827 cases.

Dr Arun Shah, leading paediatrician and former president of Indian Academy of Paediatrics, told The Indian Express: “All reasons responsible for spread of the virus are overlapping. The spread could be because of some super-spreaders, viral loads of symptomatic and asymptomatic cases, gross violation of social distancing norms, density of population and epidemiological reasons.”

A senior health department official said, “It is an interesting pattern. The Central team that visited Bihar might look at this aspect as well. It might also suggest that chances of migrants and their contacts spreading the infection are stabilising now.”

While an estimated 40 lakh people returned to Bihar, the state disaster management figures say 15,16,196 people stayed at quarantine centres.