Meanwhile, the authorities say recent water tests have found no abnormalities.
The Health Ministry said that six Byureghavan residents, including children, sought medical care with similar symptoms on Sunday.
Nune Harutiunian, head of the infectious diseases department at Abovyan’s Medical Center, said three of the patients being treated at the clinic were in moderately serious condition. Their symptoms included nausea, vomiting, diarrhea, abdominal pain, and fever, she added.
The latest incident follows two previous cases of multiple hospitalizations with similar complaints. In April, about 30 people called emergency services in Byureghavan, with 11 subsequently hospitalized. Another six people were hospitalized in July.
Residents have repeatedly linked the illnesses to the town’s drinking water.
One resident whose school-age son was hospitalized over the weekend said he had drunk tap water before becoming ill. She said she had also learned from other parents in the school that their children were experiencing similar symptoms.
“If it’s not from the water, then what is it from?” she asked.
The Health Ministry said specialists from the National Center for Disease Control and Prevention (NCDCP) took water samples once a week in August from different addresses in Byureghavan, with laboratory tests finding no deviations.
On Monday, the NCDCP, together with the water operator, Veolia Djur, and the Health and Labor Inspection Body, also collected samples from the homes of people who had sought medical assistance and from other addresses in the town, which has about 12,000 residents and is located some 15 kilometers northeast of Yerevan.
Despite the reported absence of abnormalities in recent water tests, local residents have been advised to use tap water only after boiling it.
Some residents told RFE/RL’s Armenian Service that during the summer they had access to water for no more than four hours a day. They also complained of an unpleasant smell in the tap water and abdominal pain after drinking it, saying they had to buy bottled drinking water from stores.
Two criminal investigations have been opened by the Investigative Committee in connection with the previous cases. In one of them, the NCDCP did find some abnormalities in the water quality. The committee said on Monday that expert examinations commissioned in those cases have not yet produced conclusions.
No criminal case has been opened over the latest incident, the committee said, adding that residents had contacted police in the previous cases, after which the reports were forwarded to investigators. No such report has been filed in connection with the latest case.
Veolia Djur declined to comment on the issue, instead recommending that official updates from the Health Ministry be followed.
Byureghavan Mayor Hakob Balasian said the town receives its water from springs in Nurnus, a village about three kilometers north of the town. He said he does not know at what point along the route the water may have become contaminated, or whether it has been contaminated at all, and that he is awaiting the results of the examinations.
“Veolia Djur replaced approximately one kilometer of water pipes approaching the town in 2022-23 in an effort to improve water quality, increase supply and reduce losses, but the desired improvement in water availability has not been achieved,” Balasian said.
According to the mayor, Byureghavan’s water pipelines are in satisfactory condition, with about 50 percent of the network having been replaced by the previous operator. He said Veolia Djur had also carried out work and that he had repeatedly reported to the relevant authorities about problems with the town’s drinking-water network.
Armenia’s Water Committee has not yet replied to a written inquiry by RFE/RL’s Armenian Service about whether inspections or studies of Byureghavan’s water-supply system were carried out following the outbreaks of intestinal infection this year and whether a source of suspected water contamination was identified.