Photo: Screenshot from Sina Weibo

Two young swimmers tested positive for adenovirus on Monday night after swimming in a public swimming pool in Leshan city, Southwest China's Sichuan Province, where more than 140 swimmers suffered from symptoms of fever and cough suspiciously derived from adenovirus since early July. The pool has since suspended operation for investigation. 

A thorough inspection into the Xingyuedong swimming pool was launched by local authorities on Sunday following complaints from local swimming learners who suffered from symptoms including fever and cough after swimming in the swimming pool located in Shawan district in Leshan. 

The screening among 147 swimming learners from the swimming pool showed that two children tested positive for adenovirus and they were reportedly in stable condition, according to a report from China Central Television (CCTV). A preliminary judgment suggested the disease was caused by adenovirus. 

According to a parent surnamed Liu, her 7-year-old son suffered from a continuous high fever and a series of other symptoms including headache, dizziness, abdominal pain, low fever after he had a swimming lesson at the swimming pool on July 20, according to media reports. 

Through communication with the parents of other young swimming learners, Liu learnt that over a hundred children learning swimming at the pool had suffered from similar symptoms since early- and mid-July and quite a few had tested positive for adenovirus. 

A manager surnamed Li from the swimming pool told the media that the local authorities have launched an investigation into the incident and the swimming pool will cooperate with the follow-up work. 

The swimming pool was ordered to suspend operation after the incident happened, according to an official surnamed Li from the local culture, sports and tourism bureau of Shawan district, which supervises the business operation qualification of the swimming pool. The swimming pool is qualified for operation with necessary facilities and personnel, Li told the Global Times on Tuesday. 

The local disease prevention and control authority of Shawan district who is responsible for the water quality of the swimming pool has immediately engaged in the investigation into the incident. The center had collected samples from the swimming pool, but so far no progress has been made in the investigation. The testing results will come out in 72 hours, according to media reports. 

An official surnamed Wu from the local health authority of Shawan district told the Global Times that a green passage has been set up at the People's Hospital of Leshan Shawan to treat children who had swum in the swimming pool and developed related symptoms. 

An article published on Monday by the local disease prevention and control center of Shawan district on its official WeChat account shows that the adenovirus, rather than a new type of virus, is a common virus that causes respiratory infections in children. 

Despite of its strong transmission capacity and the ability to infect everyone, children aged 5 or below, especially those infants aged from 6 months to 2 years, are particularly vulnerable. The average latent period of the infection is between three days to eight days. 

Respiratory droplet transmission is the major channel of transmission for adenovirus, which is followed by transmission through contact and through fecal-oral route, according to the article. 

The article pointed out that the adenovirus can also spread through contaminated swimming pool water. 

According to the article, adenovirus is a self-limiting disease and there is no specific medicine for the disease at present. Patients should visit the hospital as early as possible and those with light symptoms will recover by themselves in a week or so. 

It was the second case of swimming pool exposed of suspicious adenovirus contamination in Sichuan this month. Shifang city in Sichuan announced on July 21 that several parents complained about their children suffering from fever and other symptoms after swimming in a local swimming pool. As of July 21, 25 children who tested positive for adenovirus have been treated at the local hospitals. The swimming pool has also suspended operation.