According to the official Xinhua News Agency, residents were asked not to move until all nucleic acid testing results are available.
Xinhua reported that authorities have conducted almost 12,000,000 tests and received 7.8 million samples. The first cases of infection were reported in the city, located only an hour away from Beijing. Beijing will host the Winter Olympics starting February 4.
The suspension of high-speed rail service between cities and other modes of transport has caused disruptions in supply chains. This includes packaged food items sold at convenience stores.
Tianjin's COVID-19 prevention & control office stated that all those who tested positive during the initial testing round were diagnosed with the omicron variant. China has only reported a few cases. It is not known what caused the outbreak and some people may have spread the variant unknowingly because they don't show symptoms.
Officials from the city said that two students at a college who had traveled by train from Tianjin earlier in the month were positive for the virus Wednesday in Dalian. It was not known which variant they had contracted.
The omicron strain spreads faster than other coronavirus strains and is already a dominant variant in many countries. It is more likely to infect those who have been vaccinated against the virus or who have been infected with other variants of it. Early studies have shown that omicron is less likely than the delta variant to cause severe illness. Vaccination and boosters still provide strong protection against serious illness, hospitalization, and death.
Millions more Chinese live in lockdown in cities, as part of China's strict "dynamic zero case policy", which has helped China contain major epidemics at a considerable cost to their local economies.
After infections among students were found, Hong Kong closed primary and kindergarten schools and banned flights to the United States. The city also held 2,500 passengers aboard a cruise ship Wednesday for coronavirus testing as part of its efforts to contain the outbreak.
After discovering that the omicron variant was spreading beyond those arriving from overseas, Hong Kong has increased its pandemic-related restrictions.
China reported 166 new COVID-19 cases in the 24 hour preceding Wednesday. These included 33 in Tianjin, 118 in Henan and eight in Xi'an. Xi'an is home to the Terracotta Warrior statues as well as major industries. A lockdown was imposed Dec. 23.
Officials also announced that Vice Premier Sun Chunlan visited Henan last week and called for increased measures to stop the spread of the omicron and delta variants. COVID-19 has reached three cities in the province: Yuzhou, Anyang, and Zhengzhou. This has prompted travel bans and various levels to lock down.
Sun stated that "It is essential to do a great job in guaranteeing living needs of people in closed and controlled communities, ensure basic medical needs for the people during an epidemic period, as well as ensure that people's needs can be addressed and resolved in a timely fashion."
Residents of Xi'an have complained about not being able to get food or other necessities.
China has fired or punished many officials who failed to perform their duties in response to the pandemic. Anyang authorities issued 61 violations notices to 11 government departments. According to a notice from the city government, punishments ranged between verbal warnings and dismissal.
The Communist Party is concerned about ensuring that the Olympics are safe from any potential outbreaks. Officials, journalists, and athletes are all operating in a closed loop bubble to avoid any contact with the public. They will not be required to go through the 21-day quarantine if they are fully vaccinated.
The International Olympic Committee also issued a document warning attendees to avoid crowds such as bars, restaurants, and to avoid any physical contact five days prior their departure.
Before they travel, attendees must submit two negative PCR tests. During their stay in China, attendees will be tested twice daily.
The IOC advised that participants should not "absolutely let your guard down" after being negative tested.
China has barred fans from outside China from attending the event and Beijing appears to be planning to only distribute a limited number of tickets to selected spectators.
China uses lockdowns in conjunction with mask mandates and detailed case tracking to stop major outbreaks.
According to Our World in Data, it has vaccinated almost 85% of its inhabitants. Although the shots have reduced the severity of diseases, they are less effective than vaccines from other countries.
China currently claims to have 3,476 COVID-19 active cases. Since the virus was first discovered in Wuhan, China in late 2019, the country has recorded 4,636 deaths from 104,189 cases.